Effects of level of brackish water and salinity on feed intake, digestion, heat energy, ruminal fluid characteristics, and blood constituent levels in growing Boer goat wethers and mature Boer goat and Katahdin sheep wethers

Small Ruminant Research 164 (2018) 70–81

Contents lists available at ScienceDirect

Small Ruminant Research journal homepage: www.elsevier.com/locate/smallrumres

Effects of level of brackish water and salinity on feed intake, digestion, heat energy, ruminal fluid characteristics, and blood constituent levels in growing Boer goat wethers and mature Boer goat and Katahdin sheep wethers H. Yirgaa,b, R. Puchalaa, Y. Tsukaharaa, K. Tesfaia, T. Sahlua, U.L. Mengistub, A.L. Goetscha, a b

T

⁎

American Institute for Goat Research, Langston University, Langston, OK, USA Department of Animal and Range Sciences, Haramaya University, Dire Dawa, Ethiopia

A R T I C LE I N FO

A B S T R A C T

Keywords: Brackish water Saline water Digestion Feed intake Goats Sheep

A study was conducted to evaluate effects of the level of a brackish water source (5596 mg/l total dissolve salts; TDS) and higher levels of TDS through addition of NaCl on feed intake, digestion, and heat energy in growing Boer goat wethers (GRO-G) and mature Boer (MAT-G) and Katahdin sheep wethers (MAT-S). Five GRO-G (22.1 ± 2.50 kg; 0.76 ± 0.121 yr of age), five MAT-G (52.2 ± 4.99 kg), and five MAT-S (65.5 ± 4.17 kg) were assigned to three simultaneous 5 × 5 Latin squares with 3-wk periods. Treatments within squares were ad libitum intake of fresh water (0-BRW), 50% fresh water and 50% brackish water (50-BRW), 100% brackish water (100-BRW), 100-BRW plus 3450 mg/l NaCl (Low-SLW), and 100-BRW plus 6900 mg/l NaCl (Mod-SLW). Total water intake was not influenced by TDS level with GRO-G or MAT-S but increased linearly with increasing TDS (P = 0.004) for MAT-G (952, 1087, 1284, 1192, and 1372 g/day for 0-BRW, 50-BRW, 100-BRW, Low-SLW, and Mod-SLW, respectively; SEM = 147.7). Organic matter (OM) intake was not influenced by water treatment with GRO-G but changed quadratically as TDS increased (P = 0.049) with MAT-G (744, 749, 785, 732, and 703; SEM = 76.3) and linearly (P = 0.065) with MAT-S (870, 867, 835, 788, and 694 g/day for 0-BRW, 50-BRW, 100BRW, Low-SLW, and Mod-SLW, respectively; SEM = 80.0). Total tract OM digestion in MAT-G and MAT-S was not influenced by water TDS level but decreased linearly (P = 0.004) and tended to change quadratically (P = 0.054) in GRO-G (59.3, 55.5, 47.8, 47.0, and 49.5% for 0-BRW, 50-BRW, 100-BRW, Low-SLW, and ModSLW, respectively; SEM = 4.67). Intake of metabolizable energy (ME) decreased linearly with increasing TDS for MAT-G (P = 0.014; 458, 458, 441, 449, and 381; SEM = 34.2) and MAT-S (P = 0.045; 384, 361, 328, 317, and 289; SEM = 33.2) and increased linearly and changed quadratically (P ≤ 0.031) for GRO-G (519, 402, 321, 319, and 363 kJ/kg BW0.75 for 0-BRW, 50-BRW, 100-BRW, Low-SLW, and Mod-SLW, respectively; SEM = 54.5). In conclusion, increasing TDS concentration in drinking water had effects on intake and digestion that differed among animal types, with ME intake of growing goats more adversely affected by increasing brackish water level compared with mature small ruminants because of decreased digestibility. Conversely, decreases in ME intake for MAT-S with increasing TDS primarily related to decreasing feed intake, with relatively small effects for MATG associated with the Mod-SLW treatment.

1. Introduction Consumption of water moderate to high in total dissolved salts or solids (TDS) by livestock and its salinity are expected to increase in the forseeable future. Saline water refers to TDS above 1000 ppm, which includes brackish water with TDS between 1000 and 10,000 ppm, with highly saline water having TDS of 10,000–15,000 (USGS, 2013; Stanton et al., 2017; Stanton and Dennehy, 2017). A better understanding of

⁎

Corresponding author. E-mail address: [email protected] (A.L. Goetsch).

https://doi.org/10.1016/j.smallrumres.2018.05.004 Received 28 July 2017; Received in revised form 19 April 2018; Accepted 4 May 2018 0921-4488/ © 2018 Elsevier B.V. All rights reserved.

factors affecting the utilization of brackish/saline water by ruminant livestock species would help identify most appropriate management practices. There are a number of ways by which saline water can adversely affect performance of ruminants, most importantly intake and digestion (Petersen et al., 2015). Consumption of water with elevated levels of TDS by ruminant livestock has been studied for many years with additions of minerals sources such as NaCl, MgCl2, NaHCO3, and Na2SO4,

Small Ruminant Research 164 (2018) 70–81

H. Yirga et al.

Table 1 Composition of water consumed by growing Boer goat wethers and mature Boer goat and Katahdin sheep wethers. 0-BRW1

50-BRW2

100-BRW3

Low-SLW4

Mod-SLW5

Item

Mean

SEM

Mean

SEM

Mean

SEM

Mean

SEM

Mean

SEM

pH Electrical conductivity (dS/m) Total dissolved salts (mg/kg) Hardness (mg/kg) Alkalinity (mg/kg as CaCO3) Bicarbonate (mg/kg) Boron (mg/kg) Calcium (mg/kg) Chloride (mg/kg) Magnesium (mg/kg) Nitrate nitrogen (mg/kg) Potassium (mg/kg) Sodium (mg/kg) Sodium adsorption ratio Sulfate (mg/kg)

8.36 0.7 446 222 175 210 0.12 38 85 31.2 0.56 6.0 43 1.3 30

0.024 0.02 14.6 3.8 5.8 6.7 0.020 1.2 1.4 0.86 0.286 0.78 4.4 0.14 11.5

8.14 4.4 2977 625 164 199 4.64 170 682 49.2 0.42 5.6 757 13.2 1115

0.040 0.06 52.0 22.0 17.3 20.7 0.024 8.8 12.6 0.37 0.220 0.25 12.0 0.21 14.0

8.08 7.8 5596 1013 177 216 9.14 297 1294 66.2 1.12 5.0 1507 20.6 2210

0.073 0.09 53.8 15.4 13.7 16.5 0.040 6.0 25.6 0.58 0.449 0.00 16.7 0.27 20.0

8.08 14.3 9431 1020 192 234 9.40 297 3558 67.6 1.20 8.6 2977 40.5 2172

0.020 0.15 96.3 3.4 7.3 9.0 0.152 1.3 41.0 0.75 0.36 0.40 22.9 0.30 42.7

8.06 20.6 13,583 1017 177 216 9.34 296 5754 67.8 1.10 13.4 4419 60.3 2200

0.040 0.19 127.6 11.2 13.2 16.1 0.075 4.4 81.4 0.37 0.212 0.87 31.8 0.45 23.2

1 2 3 4 5

0-BRW = 100% fresh or tap water and 0% brackish water. 50-BRW = 50% fresh water and 50% brackish water. 100-BRW = 100% brackish water. Low-SLW = 100-BRW plus 3450 mg/l NaCl. Mod-SLW = 100-BRW plus 6900 mg/l NaCl.

sheep wethers (MAT-S; 65.5 ± 4.17 kg) were used. The mature wethers were born in the spring of 2013 and, thus, were nearly 3 yr old when the experiment began in November, 2015. They were treated for internal parasites before a 2-wk period of adaptation to individual housing in 1.05 × 0.55 m elevated pens and plastic-coated expanded metal floors. Wethers also were situated in 0.7 × 1.2 m metabolism crates with ‘training’ head boxes for 2 days during this period. The study occurred in the winter/spring period and the facility included heating units. Ambient temperature and relative humidity were determined with Hobo® Temperature/RH Data Loggers (model number U12-011; Onset Computer Corp., Bourne, MA). Average hourly temperature, relative humidity, and temperature-humidity index (Amundson et al., 2006) were 17.4 ± 0.083 °C, 44.9 ± 0.26, and 61.6 ± 0.10, respectively. The experiment consisted of three simultaneous 5 × 5 Latin squares, with periods 3 wk in length. The first 13 days were for adaptation to treatments and the last 8 days were for measurements. Animals of each type were divided into four sets, three with four animals and one with three. Sets consisted of animals subjected to different water treatments each period. During the 8-day measurement segments, feces and urine were collected each day and calorimetry measures occurred on 2 days that varied among sets (e.g., days 14–15, 16–17, 18–19, and 20–21 for sets 1, 2, 3, and 4, respectively). There was 1 wk between periods 1 and 2 and between periods 3 and 4 when wethers were moved to group pens with partial earthen floors and pine shavings for bedding.

often to simulate natural sources of available saline water (Peirce, 1957, 1959, 1966, 1968a, 1968b; Wilson, 1966; Weeth and Hunter, 1971; Wilson and Dudzinski, 1973). Most experiments, however, have been with NaCl added to fresh water (Kil and Dryden, 2005; Yousfi et al., 2016; Castro et al., 2017; Paiva et al., 2017). Diluted seawater has been used as well (Assad and El-Sherif, 2002; Attia-Ismail et al., 2008). Very few studies have used actual natural sources of saline drinking water. Ones identified include Harper et al. (1997) and Hunter et al. (2002) with beef cattle consuming coal mine pit water in Australia, Longeragan et al. (2001) with beef cattle consuming blends of a water from a well high in sulfate and fresh water, and Sharma et al. (2017) with growing buffalo calves consuming mixtures of a brackish water source and fresh water. For small ruminants, recently Tsukahara et al. (2016) evaluated effects of 0, 33, 67, and 100% of a brackish water source with 6900 mg/l TDS on intake, digestibility, and heat energy by young Boer and Spanish goat wethers. Intake of metabolizable energy as well as heat energy were assessed, as results of Arieli et al. (1989) suggest that high salt intake could affect efficiency of energy metabolism. Although Tsukahara et al. (2016) noted some effects such as decreased digestion when brackish water was included, the overall conclusion was that effects on performance with long-term feeding would be unlikely. This is in line with suggestions of McGregor (2004) that young goats can consume water with 7000 mg/l TDS without deleterious effects, a level higher than young sheep (i.e., 5000 mg/l), less than adult sheep (10,000 mg/l), and much less than adult goats (14,000 mg/ l). Hence, the primary objective of this experiment was to evaluate effects of level of this brackish water source and with higher levels of salinity achieved through addition of NaCl on feed intake, digestion, and heat energy in growing Boer goats and also older animals, mature Boer and Katahdin sheep wethers. Other measures such as levels of some ruminal fluid and blood constituents were evaluated to more fully characterize conditions and as secondary objectives.

2.2. Treatments All five wethers of a type were assigned to the same Latin square, with five water treatments within squares as the subplot. Water treatments were fresh or tap water (0-BRW), 50% fresh water and 50% of brackish water from a well on the University farm (50-BRW), 100% brackish water (100-BRW), 100-BRW plus 3450 mg/l of NaCl (LowSLW), and 100-BRW plus 6900 mg/l of NaCl (Mod-SLW). The levels of added salt were based on a TDS level of 6900 mg/l in the brackish water source noted in a previous study (Tsukahara et al., 2016), so that there would be 50 and 100% increases in TDS relative to 100-BRW. Water was collected and water treatment mixtures were created, stored in plastic containers, and sampled weekly. Water treatment composition was determined at the Oklahoma State University Soil, Water, & Forage Analytical Laboratory (Stillwater, OK, USA; Table 1).

2. Materials and methods 2.1. Animals and housing The experimental protocol was approved by the Langston University Animal Care and Use Committee. Five growing Boer goat wethers (GRO-G) (22.1 ± 2.50 kg; 0.76 ± 0.121 yr of age), five mature Boer goat wethers (MAT-G; 52.2 ± 4.99 kg), and five mature Katahdin 71

Small Ruminant Research 164 (2018) 70–81

H. Yirga et al.

calculated as described by Eisemann and Nienaber (1990). Packed cell volume (PCV) was determined with heparinized tubes (Clay Adams; Parsippany, NJ, USA). Plasma was collected by centrifugation at 3000 × g for 20 min at 10 °C and used to determine osmolality with a model 2020 Osmometer (Advanced Instruments, Inc., Norwood, MA, USA). Moreover, aliquots of plasma stored frozen at −20 °C were later used to determine concentrations of sodium, potassium, calcium, magnesium, phosphorus, chloride, bicarbonate, urea N, creatinine, triglycerides, cholesterol, albumin, globulin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), creatine phosphokinase (CPK), and gamma-glutamyl transpeptidase (GGT) by the Oklahoma State University, Center for Veterinary Health Sciences, Oklahoma Animal Disease Diagnostic Laboratory (Stillwater, OK, USA). Moreover, concentrations of cortisol and vasopressin were determined with ELISA kits of Enzo Life Sciences (Farmingdale, NY, USA).

An amount of water above that being consumed was placed in a clean bucket and weighed. The bucket was placed in a holder or head box for the wether to drink for approximately 30 min at 08:00 and 16:00 h and weighed thereafter. A coarsely ground low to moderate quality grass hay, predominantly Johnsongrass (Sorghum halpense), was offered at approximately 120% of consumption on the preceding few days for ad libitum consumption. There was free access to a small piece of mineral salt block (American Stockman Big 6 Mineral Salt; ingredients: 96–99% NaCl, 2400 mg/kg Mn, 2400 mg/kg Fe, 260–380 mg/kg, 70 mg/kg I, and 40 mg/kg Co; Compass Minerals, Overland Park, KS, USA) placed in the bottom of each feeder. 2.3. Measures Body weight (BW) was measured before the morning meal at the beginning of periods and the start and end of segments for collection of feces and urine and calorimetry measures. The average of these values was used for most variables expressed relative to BW except for calorimetry system determinations that were based on measures at the beginning and end of that phase. Wethers resided in metabolism crates on day 14–21 for total collection of feces and urine. Urine was acidified with 30 ml of 30% (v/v) H2SO4 placed in collection vessels to maintain pH below 3.0. Composite samples of feces and urine were formed by collecting 15% daily aliquots. Feed and refusal samples were also collected daily on day 14–21 to form composite samples. Samples were analyzed for dry matter (DM), ash (AOAC, 2006), nitrogen (N; Leco TruMac CN, St. Joseph, MI, USA), neutral detergent fiber (NDF) with use of heat stable amylase (Van Soest et al., 1991) and containing residual ash, acid detergent fiber (ADF), and acid detergent lignin (ADL; filter bag technique of ANKOM Technology Corp., Fairport, NY, USA). Urine samples were analyzed for DM (lyophilization) and, subsequently, gross energy (GE) using a bomb calorimeter (Parr 6300; Parr Instrument Co., Inc., Moline, IL, USA). There was a separate room with four metabolism crates fitted with head boxes of an indirect, open-circuit respiration calorimetry system (Sable Systems International, North Las Vegas, NV, USA) for determination of heat energy (HE) as in other studies (Puchala et al., 2007, 2009). Oxygen concentration was analyzed using a fuel cell FC-1B O2 analyzer (Sable Systems International), and CH4 and CO2 concentrations were measured with infrared analyzers (CA-1B for CO2 and MA-1 for CH4; Sable Systems International). Prior to gas exchange measurements, analyzers were calibrated with gases of known concentrations. Ethanol combustion tests were performed to ensure complete recovery of O2 and CO2 produced with the same flow rates as used during measurements. Heat energy was calculated by the Brouwer (1965) equation without consideration of urinary N. Intake of digestible energy (DE) was estimated by assuming 19.33 kJ/g of digested organic matter (OM; Garrett et al., 1959), energy lost as CH4 was total CH4 emitted in l/day × 39.5388 kJ/l (Brouwer, 1965), and metabolizable energy (ME) was the difference between DE and the sum of energy in urine and methane. Recovered energy (RE) was the difference between ME and HE. Ruminal fluid samples were collected by stomach tube at 4 h after feeding on day 16 or 19 for different animal sets so that there was at least 2 days before or after calorimetry measures. The pH was measured with a digital meter and then 4 ml were placed into a tube with 1 ml of a 250 g/l metaphosphoric acid solution and frozen at −20 °C for later volatile fatty acid (VFA) analysis. Likewise, 3 ml were placed into a tube with 2 ml of 3 M HCl and frozen at −20 °C for ammonia analysis. Analyses of VFA and ammonia N were by procedures of Lu et al. (1990) and Broderick and Kang (1980), respectively. Blood samples also collected at these times, and immediately after sampling hemoglobin concentration and O2 saturation were determined with a OSM 3 Hemoximeter (Radiometer America, Westlake, OH, USA) and glucose and lactate concentrations were measured with a YSI 2300 Plus Glucose & Lactate Analyzer (YSI Inc., Yellow Springs, OH, USA). Oxygen was

2.4. Statistical analysis Data were first analyzed with a mixed effects model (Littell et al., 1998) consisting of animal type, water treatment, and their interaction, with period included as a repeated measure. Animal within type was the error term for testing the effect of animal type and residual error was used to test effects of water treatment and animal type × water treatment. Animal type means were separated by least significant difference with a protected F-test. Water treatment means were evaluated with linear, quadratic, cubic, and quartic contrasts for effects of level of TDS assuming an equal difference or spacing among treatments. No quartic effects were significant or tended to be significant (i.e., P > 0.10), and there was only one variable for which a cubic effect had a P value between 0.05 and 0.10. Contrasts were conducted separately for each animal type when there was an animal type × water treatment interaction (P < 0.05) and in some cases with a nonsignificant interaction in order to gain a better understanding of animal types contributing to effects of level of TDS in drinking water. In this regard, there were many variables for which the significance of overall contrasts for level effects were not in close accordance with P values for contrasts of individual animal types. Likewise, in some instances the P value was significant for the overall level effect but not for any individual animal type. Therefore, the Bartlett test for the homogeneity of variance among animal treatments was evaluated. Variance was not homogeneous among animal types for many of the most important variables. Hence, the initial analysis was employed to address differences only among animal types. For seven variables with an interaction (P < 0.05) between animal type and water treatment (ruminal fluid levels of acetate, propionate, and total VFA and plasma concentrations of lactate, bicarbonate, Ca, and Mg), animal type differences were addressed within each water treatment. Effects of level of TDS in drinking water were evaluated by mixed effects analysis conducted separately for each animal type with a model consisting of water type, period as a repeated measure, and animal as a random effect. Orthogonal contrasts were used as noted before. 3. Results 3.1. Water composition The composition of 100-BRW (Table 1) differed somewhat from brackish drinking water obtained from the same well used in the previous study of Tsukahara et al. (2016). Concentrations of Na, Ca, Mg, chloride, sulfate, and TDS and electrical conductivity, alkalinity, and hardness in 100-BRW were less than in the earlier experiment. The TDS levels in Low-SLW and Mod-SLW relative to 100-BRW were slightly greater than expected with NaCl additions of 3450 and 6900 mg/l, respectively. With a similar level of bicarbonate in 0-BRW and 100-BRW, bicarbonate constituted a much greater proportion of TDS in 0-BRW 72

Small Ruminant Research 164 (2018) 70–81

H. Yirga et al.

(P = 0.018). There was an animal type × water treatment interaction in total VFA concentration (P < 0.05). These interactions were largely because of differences among animal types with water treatments of 100-BRW and Mod-SLW, with relatively low levels for MAT-S. The P values for linear and quadratic effects of level of TDS in drinking water were less than 0.10 for concentrations of acetate and total VFA with GRO-G and MAT-G, with values generally increasing as TDS increased. There were some effects of water treatment on molar percentages of VFA, primarily with GRO-G. There was a linear increase in the percentage of acetate with increasing drinking water TDS level (P = 0.006) and a tendency for a decrease in that of propionate (P = 0.068), with the change in acetate perhaps countered by a trend for a linear decrease in butyrate (P = 0.053). In accordance, the acetate to propionate ratio for GRO-G increased linearly as TDS level increased (P = 0.020).

than other water treatments. The brackish water used would be classified as Group 3 of the USGS (Stanton et al., 2017), being a sodiumchloride-dominant water type with high TDS relative to other brackish water groups. 3.2. Hay and refusal composition Offered and refused grass hay was 10.5 ± 0.50 and 11.7 ± 0.28% ash, 1.19 ± 0.030 and 1.30 ± 0.032% N, 70.8 ± 0.43 and 68.4 NDF, 46.8 ± 0.15 and 46.6 ± 0.33% ADF, and 15.9 ± 2.98 and 14.2 ± 1.09% ADL, respectively. Based on these values, nutritive value was slightly lower than expected based on a preliminary analysis of samples taken from large round bales before the experiment, such as CP and NDF levels of 10.2 and 65.7%, respectively. In contrast to the previous experiment of Tsukahara et al. (2016), the level of CP was less in hay offered than refused.

3.4. Blood constituent concentrations

3.3. Ruminal fluid characteristics

There were many differences among animal types in blood constituent concentrations, and there were interactions (P < 0.05) between animal type and water treatment for Ca, Mg, bicarbonate, and lactate (Table 3). The level of K was greatest and of chloride was lowest among animal types for GRO-G (P < 0.05). The urea N concentration was lower for MAT-S than for GRO-G (P < 0.05) and tended to be lower for MAT-S vs. MATG (P = 0.077). The triglyceride level was

Ruminal pH was not affected by animal type (P > 0.05) but decreased linearly with increasing TDS in drinking water for MAT-G (P < 0.001) and tended to do so as well for GRO-G (P = 0.073; Table 2). Ruminal ammonia N concentration was similar among animal types and decreased linearly with increasing TDS for MAT-G

Table 2 Effects of levels of brackish water and NaCl in drinking water on ruminal fluid pH and concentrations of ammonia nitrogen and volatile fatty acids in growing Boer goat wethers and mature Boer goat and Katahdin sheep wethers. Contrast P value1

Water treatment2

Item3

AT4

Linear

Quadratic

0-BRW

50-BRW

100-BRW

Low-SLW

Mod-SLW

SEM

pH

GRO-G MAT-G MAT-S GRO-G MAT-G MAT-S

0.073 < 0.001 0.874 0.714 0.018 0.437

0.551 0.347 0.190 0.305 0.698 0.494

6.90 6.90 6.94 7.84 7.85 6.97

6.83 6.95 6.81 8.64 6.88 7.20

6.65 6.79 6.84 7.93 7.57 8.94

6.78 6.83 6.89 7.07 5.95 7.24

6.65 6.72 6.92 8.90 6.46 8.05

0.084 0.045 0.077 0.703 0.642 0.867

GRO-G MAT-G MAT-S

0.051 0.034 0.253

0.090 0.060 0.139

56.1 66.7 58.3

62.2 61.6 66.2

73.9b 67.5ab 60.8a

64.8 65.7 59.8

68.0b 73.8b 54.7a

3.85 3.57 4.82

GRO-G MAT-G MAT-S GRO-G MAT-G MAT-S GRO-G MAT-G MAT-S GRO-G MAT-G MAT-S GRO-G MAT-G MAT-S GRO-G MAT-G MAT-S GRO-G MAT-G MAT-S

0.006 0.507 0.989 0.068 0.344 0.887 0.017 0.043 0.052 0.053 0.778 0.515 0.023 0.043 0.229 0.003 0.082 0.761 0.020 0.445 0.908

0.482 0.244 0.731 0.669 0.347 0.229 0.185 0.549 0.137 0.869 0.157 0.284 0.114 0.956 0.570 0.509 0.734 0.287 0.559 0.236 0.408

74.5 76.6 74.5 15.5 14.7 15.1 0.64 0.61 0.61 8.0 6.6 8.4 0.84 0.91 0.85 0.54 0.49 0.49 4.83 5.28 4.94

74.6 76.9 75.6 15.6 14.1 15.2 0.61 0.60 0.58 7.9 7.3 7.4 0.81 0.77 0.84 0.53 0.43 0.47 4.80 5.50 5.01

75.9 75.8 74.4 15.2 14.9 15.3 0.52 0.58 0.62 7.2 7.5 8.3 0.65 0.80 0.86 0.48 0.45 0.47 5.00 5.11 4.89

76.4 76.2 74.8 14.7 14.7 15.6 0.48 0.52 0.62 7.4 7.4 7.6 0.55 0.67 0.95 0.44 0.43 0.46 5.26 5.19 4.81

76.2 78.1 74.8 15.1 13.7 14.8 0.53 0.47 0.75 7.0 6.8 8.0 0.69 0.61 1.04 0.46 0.37 0.51 5.07 5.74 5.06

0.74 1.22 0.57 0.37 0.51 0.42 0.051 0.065 0.082 0.49 0.59 0.37 0.086 0.131 0.183 0.035 0.045 0.042 0.171 0.275 0.168

Ammonia N (mg/100 ml)

VFA Total (mmol/l)

Molar% Acetate

Propionate

Isobutyrate

Butyrate

Isovalerate

Valerate

Acetate:propionate

a,b

Animal type means within water treatment without a common superscript letter differ (P < 0.05). Linear and Quadratic = effects of level of total dissolve salts in drinking water. 2 0-BRW = 100% fresh or tap water and 0% brackish water; 50-BRW = 50% fresh water and 50% brackish water; 100-BRW = 100% brackish water; LowSLW = 100-BRW plus 3450 mg/l NaCl; Mod-SLW = 100-BRW plus 6900 mg/l NaCl. 3 N = nitrogen; VFA = volatile fatty acids. 4 AT = animal type. 1

73

Small Ruminant Research 164 (2018) 70–81

H. Yirga et al.

Table 3 Effects of levels of brackish water and NaCl in drinking water on blood constituent concentrations in growing Boer goat wethers and mature Boer goat Katahdin sheep wethers. Contrast P value1

Water treatment2

Item3

AT4

Linear

Quadratic

0-BRW

50-BRW

100-BRW

Low-SLW

Mod-SLW

SEM

Sodium (mg/dl)

GRO-G MAT-G MAT-S GRO-Gb MAT-Ga MAT-Sa GRO-G MAT-G MAT-S GRO-G MAT-G MAT-S GRO-G MAT-G MAT-S GRO-Gb MAT-Gb MAT-Sa GRO-G MAT-G MAT-S GRO-G MAT-G MAT-S GRO-Gb MAT-Ga MAT-Sa GRO-Ga MAT-Gab MAT-Sb GRO-G MAT-G MAT-S GRO-G MAT-G MAT-S GRO-Gb MAT-Ga MAT-Sab GRO-G MAT-G MAT-S GRO-Gb MAT-Ga MAT-Sc GRO-G MAT-G MAT-S GRO-Ga MAT-Ga MAT-Sb GRO-G MAT-G MAT-S GRO-G MAT-G MAT-S GRO-Gb MAT-Gb MAT-Sa GRO-Ga MAT-Ga MAT-Sb GRO-G MAT-G MAT-S GRO-G MAT-G MAT-S

0.526 0.047 0.942 0.732 0.078 0.617 0.036 0.105 0.296 0.001 0.498 0.692 0.546 0.198 0.397 0.237 0.823 0.303 0.501 0.013 0.354 0.097 0.332 0.121 0.511 0.075 0.290 0.040 0.376 0.265 0.383 0.900 0.088 0.713 0.249 0.005 0.559 0.153 0.583 0.699 0.666 0.890 0.022 0.049 1.000 0.803 0.180 0.743 0.229 0.275 0.606 0.047 0.646 0.235 0.004 0.098 0.008 0.169 0.915 0.284 0.006 0.718 0.605 0.787 0.524 0.496 0.147 0.898 0.814

0.334 0.010 0.667 0.631 0.241 0.332 0.188 0.244 0.149 0.112 0.260 0.607 0.222 0.456 0.224 0.891 0.723 0.056 0.569 < 0.001 0.431 0.809 0.198 0.766 0.536 0.858 0.174 0786 0.355 0.343 0.129 0.335 0.454 0.975 0.204 0.016 0.422 0.056 0.889 0.904 0.739 0.754 0.953 0.869 0.648 0.529 0.665 0.234 0.426 0.579 0.618 0.216 0.897 0.538 0.659 0.155 0.100 0.814 0.126 0.573 0.797 0.421 0.185 0.361 0.382 0.164 0.514 0.216 0.570

336 328 340 22.8 19.3 20.2 9.12a 8.60a 10.24ab 3.12b 2.41a 2.51a 7.60 6.07 6.00 107.2 108.4 104.2 23.4 24.8 24.6 306.3 305.7 309.1 18.0 14.2 10.0 60.1 60.1 76.0 58.2 57.5 64.8 39.8a 23.5a 71.0b 20.0 11.4 18.0 1.50 1.69 1.59 27.8 20.6 34.4 45.4 47.8 44.0 63.0 69.2 103.6 15.0 12.2 11.0 83.2 71.6 113.6 100.0 104.6 43.6 37.2 34.2 66.2 35.6 34.8 17.3 763 620 556

336 335 340 21.6 20.5 19.0 9.22b 8.56a 10.16c 2.90b 2.51a 2.59ab 7.78 5.94 6.44 108.4 108.0 107.2 23.8 26.2 24.0 309.4 309.4 304.1 17.2 12.2 10.0 56.6 67.9 76.0 58.4 55.8 62.2 40.3ab 21.2a 57.8b 21.8 15.0 20.4 1.47 1.43 1.92 27.8 20.4 32.6 45.0 45.6 42.2 66.2 69.0 104.2 14.2 12.2 15.0 77.8 71.6 111.8 122.2 93.2 56.6 33.2 30.8 48.0 20.6 34.5 21.2 521 679 433

340 338 340 22.2 21.4 19.9 8.98a 8.88a 10.00b 2.61 2.48 2.54 8.63 7.64 7.30 107.8 107.9 104.4 24.4a 29.2b 23.2a 309.4 309.5 313.0 16.2 13.8 10.0 56.6 69.0 72.5 55.1 53.7 59.0 36.9 20.6 36.1 20.9 16.5 17.4 1.45 1.62 1.50 26.6 20.4 33.8 45.0 48.2 43.2 62.2 68.6 85.8 12.4 11.0 11.0 68.0 73.4 100.0 105.2 96.2 42.8 33.2 37.2 52.9 22.3 35.5 33.9 676 845 559

338 336 342 22.9 20.1 19.9 9.14a 8.74a 10.16b 2.56 2.41 2.51 7.94 7.36 6.28 109.2 108.6 105.6 22.4a 24.8ab 26.0b 308.1 306.2 313.9 16.0 11.4 9.4 53.0 74.3 69.0 56.1 54.8 55.3 39.7 24.4 41.0 25.0 15.2 17.2 1.48 1.57 1.55 25.2 22.8 34.2 47.4 48.6 42.4 62.6 63.6 115.0 14.2 14.0 9.6 69.4 69.8 93.4 120.6 89.0 51.4 30.6 35.6 58.9 27.0 39.1 29.7 977 731 362

327 334 339 22.7 21.1 19.9 8.76a 8.74a 10.12b 2.56 2.39 2.51 7.92 7.08 6.66 109.8 108.4 103.8 23.0 22.8 25.2 312.8 300.1 315.3 16.8 11.0 11.4 49.5 67.2 74.3 64.0 58.8 58.0 37.3 28.5 46.6 20.6 14.4 17.6 1.44 1.52 1.74 25.4 21.6 33.6 44.6 48.2 44.6 59.6 68.0 105.4 13.0 12.2 10.2 53.2 61.4 102.4 122.4 105.4 64.2 28.8 33.0 68.2 32.7 34.9 19.4 795 620 529

8.3 2.0 2.5 1.06 0.53 0.64 0.163 0.151 0.212 0.162 0.115 0.097 0.701 0.796 0.410 1.52 0.83 0.71 1.03 0.64 1.11 2.50 4.51 4.35 1.88 1.39 0.67 6.33 7.01 4.93 4.48 3.89 3.49 9.34 3.95 8.99 2.62 1.89 2.24 0.087 0.201 0.159 2.08 2.10 1.13 2.31 1.09 1.32 4.26 4.18 11.06 1.13 1.48 1.77 16.16 26.26 13.45 11.59 8.92 10.84 2.28 3.26 11.37 8.79 13.58 6.72 115.2 166.3 122.3

Potassium (mg/dl)

Calcium (mg/dl)

Magnesium (mg/dl)

Phosphorus (mg/dl)

Chloride (mmol/l)

Bicarbonate (mmol/l)

Osmolality (mOsm/l)

Urea N (mg/dl)

Creatinine (μmol/l)

Glucose (mg/dl)

Lactate (g/dl)

Triglycerides (mEq/l)

Cholesterol (mg/dl)

Albumin (g/l)

Globulin (g/l)

AST (IU/l)

ALT (IU/l)

ALP (IU/l)

CPK (IU/l)

GGT (IU/l)

Cortisol (nmol/l)

Vasopressin (mmol/l)

(continued on next page)

74

Small Ruminant Research 164 (2018) 70–81

H. Yirga et al.

Table 3 (continued) Contrast P value1

Water treatment2

Item3

AT4

Linear

Quadratic

0-BRW

50-BRW

100-BRW

Low-SLW

Mod-SLW

SEM

PCV (%)

GRO-Ga MAT-Ga MAT-Sb GRO-Ga MAT-Ga MAT-Sb GRO-G MAT-G MAT-S GRO-Ga MAT-Ga MAT-Sb

0.161 0.357 0.377 0.122 0.497 0.427 0.222 0.616 0.662 0.078 0.333 0.453

0.068 0.242 0.719 0.036 0.117 0.260 0.379 0.569 0.287 0.484 0.117 0.610

23.1 26.5 43.4 83 96 162 67.8 64.3 59.5 7.62 8.40 13.52

25.1 25.3 41.7 87 93 156 69.1 68.5 71.0 7.88 8.68 15.16

24.6 25.3 42.2 90 90 156 64.0 67.3 64.6 7.80 8.06 13.90

23.1 26.7 41.7 82 95 153 60.8 60.0 61.5 6.70 7.80 12.84

21.3 27.6 41.4 76 99 158 66.1 72.5 60.7 6.88 9.80 13.18

1.49 1.49 1.70 4.9 4.9 5.6 6.42 4.74 5.10 0.534 0.665 1.223

Hb (g/l)

O2 Hb saturation (%)

O2 (mmol/l)

a,b,c

Main effect animal type means and interaction means within water type without a common superscript letter differ (P < 0.05). Linear and Quadratic = effects of level of total dissolve salts in drinking water. 2 0-BRW = 100% fresh or tap water and 0% brackish water; 50-BRW = 50% fresh water and 50% brackish water; 100-BRW = 100% brackish water; LowSLW = 100-BRW plus 3450 mg/l NaCl; Mod-SLW = 100-BRW plus 6900 mg/l NaCl. 3 N = nitrogen; AST = aspartate amino-transferase; ALT = alanine amino-transferase; ALP = alkaline phosphatase; CPK = creatine phosphokinase; GGT = gamma-glutamyl transpeptidase; PCV = packed cell volume; Hb = hemoglobin. 4 AT = animal type. 1

(P = 0.099) than for GRO-G and was numerically less than for MAT-S (P = 0.121). Similar differences were noted for total water intake, which includes water from feed consumed. The only animal type for which water intake increased linearly with increasing TDS concentration in drinking water was MAT-G (P = 0.004, 0.004, 0.005, and 0.001 for drinking water in g/day and total water intake in g/day, g/kg BW0.75, and g/g DM intake, respectively). Urinary water loss was lowest among animal types for GRO-G (P < 0.05; Table 4). Urinary water for each animal type decreased linearly with increasing TDS level in drinking water (P ≤ 0.012). There was a quadratic effect (P = 0.004) of drinking water TDS level on urinary water of GRO-G due to a much higher value with Mod-SLW than other water treatments, which corresponds to numerically greatest total water intake as well (i.e., 1047 vs. a mean of 884 g/day for the other water treatments). Fecal water loss was lower for GRO-G vs. MAT-S (P < 0.05) and tended to be lower than for MAT-G as well (P = 0.051). Water in feces was not influenced by water treatment with any animal type. Based on water intake and TDS level, ash intake from drinking water in g/day increased at an increasing rate as TDS increased for GRO-G and MAT-G (P < 0.05) and increased linearly for MAT-S as the TDS level in water increased (P < 0.001). The contribution of ash in water to total ash intake increased linearly as TDS concentration in water increased as well (P < 0.001).

greater for GRO-G than for MAT-G, with an intermediate level for MATS (P > 0.10). The albumin concentration ranked (P < 0.05) MATG < GRO-G < MAT-S. Concentrations of AST and GGT were greater for MAT-S than for GRO-G and MAT-G (P < 0.05) and that for CPK was lowest for MAT-S (P < 0.05). Concentrations of PCV, hemoglobin, and O2 were greatest among animal types for MAT-S (P < 0.05). The animal type × water treatment interaction in plasma Ca concentration involved highest (P < 0.05) levels for MAT-S with all water treatments except 0-BRW and a difference (P < 0.05) between GRO-G and MAT-G only with the water treatment of 50-BRW. The interaction in the Mg concentration was because of relatively high levels for GRO-G consuming 0-BRW and 50-BRW. Likewise, the interaction in bicarbonate concentration was because of a higher level for MAT-G vs. GRO-G and MAT-S with 100-BRW (P < 0.05) and a higher level for MAT-S than for GRO-G with Low-SLW (P < 0.05). The interaction in lactate concentration was a result of relatively high concentrations for MAT-S consuming 0-BRW and 50-BRW. There were many linear effects of the TDS level in drinking water on concentrations of blood constituents and some quadratic effects also (Table 3). However, there were very few instances where such effects were observed for more than one animal type. The albumin concentration for MAT-G increased and then declined as the TDS level rose (P = 0.047 and 0.010 for linear and quadratic, respectively). Levels of Ca, Mg, and creatinine in GRO-G decreased linearly with increasing TDS (P = 0.036, 0.001, and 0.040, respectively). The bicarbonate level in MAT-G increased and then decreased markedly with increasing TDS level (P = 0.013 and < 0.001 for linear and quadratic, respectively). The lactate concentration for MAT-S decreased and then increased with increasing TDS level (P = 0.005 and 0.016 for linear and quadratic, respectively). The albumin concentration in GRO-G linearly increased (P = 0.022) and that in MAT-G decreased (P = 0.049) as the TDS concentration increased. Concentrations of the enzymes ALT, ALP, and GGT all decreased linearly in GRO-G as the TDS level increased (P = 0.047, 0.004, and 0.006, respectively), and the same change in ALP was observed for MAT-S (P = 0.008).

3.6. Feed intake and digestion Feed and total DM intakes (i.e., adjusted for minerals from drinking water) were affected by animal type and water treatment similarly (Table 4). The three expressions of DM intake, DM digestibility, and digested DM intake all were influenced by animal type (P ≤ 0.008). Intake of DM in g/day was lower for GRO-G than for mature animals (P < 0.05) but in% BW ranked (P < 0.05) GRO-G > MAT-G > MAT-S. Conversely, DM intake in g/kg BW.75 was greatest for GRO-G (P < 0.05) and similar between MAT-G and MAT-S. Total tract digestibility of DM was lowest among animal types (P < 0.05) for GRO-G and numerically greater for MAT-G vs. MAT-S (P = 0.131). As a consequence of these differences, intake of digestible DM in g/day was similar between MAT-G and MAT-S and lowest among animal types for GRO-G (P < 0.05). Intake and digestion results for OM, NDF, and ADF were similar to those for DM. Total DM intake by GRO-G was not affected by water treatment (Table 4). Dry matter intake by MAT-G tended to be greatest with the

3.5. Water intake and losses All expressions of water intake and losses, except for water intake relative to DM intake, were affected by animal type (P < 0.05; Table 4). Drinking water intake in g/day was greater for MAT-S than for GRO-G (P < 0.05), and that for MAT-G tended to be greater 75

Small Ruminant Research 164 (2018) 70–81

H. Yirga et al.

Table 4 Effects of levels of brackish water and NaCl in drinking water on intake of water and ash and intake and digestion of dry matter, organic matter, nitrogen, neutral detergent fiber, and acid detergent fiber in growing Boer goat wethers and mature Boer goat and Katahdin sheep wethers. Contrast P value1 Item3 Water intake Drinking (g/day)

Total g/day

g/kg BW0.75

g/g DM intake

Water loss (g/day) Urinary

Fecal

Water ash intake g/day

% total ash intake

Feed DM Intake (g/day)

Digestion (%)

Digestion (g/day)

Total DM Intake (g/day)

Intake (% BW)

Intake (g/kg BW0.75)

Digestion (%)

Digestion (g/day)

OM Intake (g/day)

Digestion (%)

Digestion (g/day)

Nitrogen Intake (g/day)

Water treatment2

AT4

Linear

Quadratic

0-BRW

50-BRW

100-BRW

Low-SLW

Mod-SLW

SEM

GRO-Ga MAT-Gab MAT-Sb

0.238 0.004 0.594

0.140 0.544 0.400

913 935 1525

823 1070 1367

881 1266 1320

871 1175 1386

1035 1356 1397

93.8 146.5 159.7

GRO-Ga MAT-Gab MAT-Sb GRO-Gb MAT-Ga MAT-Sa GRO-G MAT-G MAT-S

0.239 0.004 0.585 0.341 0.005 0.520 0.043 0.001 0.419

0.138 0.536 0.409 0.117 0.507 0.358 0.341 0.847 0.068

925 952 1545 94.4 54.0 72.7 1.47 1.21 1.73

835 1087 1390 83.1 61.3 65.1 1.49 1.31 1.44

892 1284 1340 87.8 71.9 61.1 1.55 1.50 1.46

883 1192 1406 89.0 66.9 65.1 1.55 1.51 1.63

1047 1372 1414 103.4 76.1 65.6 1.83 1.73 1.83

94.3 147.7 160.4 7.98 6.59 8.42 0.123 0.108 0.205

GRO-Ga MAT-Gb MAT-Sb GRO-Ga MAT-Gab MAT-Sb

0.001 0.002 0.012 0.487 0.203 0.297

0.004 0.174 0.126 0.410 0.360 0.980

245 423 507 312 413 503

227 380 481 298 381 487

224 476 522 281 437 477

282 513 563 296 384 446

433 605 672 293 376 438

44.5 72.1 74.6 21.0 44.0 58.5

GRO-G MAT-G MAT-S GRO-G MAT-G MAT-S

< 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001

0.034 0.049 0.119 0.078 0.405 0.155

0.4 0.4 0.7 0.6 0.6 0.9

2.5 3.2 4.1 4.1 3.7 4.3

4.9 7.1 7.4 7.6 9.4 8.4

8.2 11.1 13.1 12.7 14.5 13.6

14.1 18.4 19.0 19.4 20.0 19.1

1.05 1.47 1.34 1.20 1.52 0.93

GRO-Ga MAT-Gb MAT-Sb GRO-Ga MAT-Gb MAT-Sb GRO-Ga MAT-Gb MAT-Sb

0.210 0.149 0.066 0.003 0.355 0.419 0.018 0.072 0.052

0.260 0.048 0.483 0.054 0.833 0.138 0.035 0.084 0.958

640 820 968 57.1 66.7 62.2 361 546 586

565 834 971 53.6 67.1 58.1 298 560 552

563 873 922 45.3 61.3 58.1 241 557 522

568 804 872 44.4 67.5 56.0 258 544 483

566 781 773 47.0 62.9 60.1 271 487 459

39.8 86.3 89.7 4.81 2.41 2.83 31.7 60.2 49.2

GRO-Ga MAT-Gb MAT-Sb GRO-Gc MAT-Gb MAT-Sa GRO-Gb MAT-Ga MAT-Sa GRO-Ga MAT-Gb MAT-Sb GRO-Ga MAT-Gb MAT-Sb

0.331 0.372 0.093 0.193 0.186 0.084 0.204 0.204 0.086 0.006 0.497 0.605 0.040 0.209 0.093

0.239 0.056 0.503 0.144 0.037 0.555 0.148 0.038 0.538 0.046 0.791 0.127 0.031 0.102 0.926

640 820 969 3.04 1.74 1.60 65.1 45.6 44.7 57.2 66.8 62.2 361 546 586

567 839 975 2.62 1.80 1.62 56.4 47.0 45.1 53.8 67.2 58.2 301 563 556

568 880 930 2.61 1.86 1.51 56.4 48.7 42.3 45.7 61.7 58.5 246 564 529

576 815 885 2.71 1.73 1.47 58.1 45.1 40.9 45.2 68.0 56.7 266 555 496

580 800 792 2.67 1.68 1.31 57.6 44.1 36.5 48.3 63.7 61.0 285 505 478

40.3 87.1 90.3 0.150 0.094 0.140 3.10 2.98 3.89 4.71 2.40 2.84 31.6 61.2 49.9

GRO-Ga MAT-Gb MAT-Sc GRO-Ga MAT-Gb MAT-Sb GRO-Ga MAT-Gb MAT-Sb

0.209 0.134 0.065 0.004 0.302 0.361 0.021 0.064 0.046

0.270 0.049 0.444 0.054 0.918 0.183 0.043 0.076 0.887

571 744 870 59.3 68.9 64.1 335 511 541

505 749 867 55.5 69.0 60.2 277 516 512

504 785 835 47.8 63.9 60.5 229 519 492

509 732 788 47.0 69.7 58.3 242 511 454

506 703 694 49.5 64.8 61.7 253 451 422

35.2 76.3 80.0 4.67 2.21 2.73 28.2 54.8 44.4

GRO-G MAT-G MAT-S

0.253 0.279 0.267

0.211 0.036 0.673

8.1 8.6 10.9

6.8 9.1 10.8

6.8 9.9 10.7

6.8 8.4 9.9

6.9 8.2 9.2

0.59 1.30 1.20

(continued on next page) 76

Small Ruminant Research 164 (2018) 70–81

H. Yirga et al.

Table 4 (continued) Contrast P value1 Item3 Digestion (%)

Digestion (g/day)

NDF Intake (g/day)

Digestion (%)

Digestion (g/day)

ADF Intake (g/day)

Digestion (%)

Digestion (g/day)

Water treatment2

AT4

Linear

Quadratic

0-BRW

50-BRW

100-BRW

Low-SLW

Mod-SLW

SEM

GRO-G MAT-G MAT-S GRO-Ga MAT-Gb MAT-Sb

0.024 0.620 0.905 0.033 0.212 0.643

0.034 0.280 0.324 0.043 0.092 0.755

50.8 50.5 54.5 4.2 4.7 5.7

45.4 54.4 46.0 3.1 5.0 5.0

33.7 51.6 51.0 2.1 5.2 5.5

35.4 53.6 47.5 2.4 4.7 4.9

40.3 48.4 52.8 2.7 4.0 5.2

5.82 3.92 5.26 0.53 0.94 0.77

GRO-Ga MAT-Gb MAT-Sb GRO-Ga MAT-Gb MAT-Sb GRO-Ga MAT-Gb MAT-Sb

0.189 0.251 0.045 0.003 0.457 0.254 0.017 0.150 0.024

0.284 0.065 0.407 0.066 0.598 0.228 0.039 0.135 0.767

455 596 703 59.7 70.0 64.8 269 415 443

403 609 704 56.0 70.1 61.8 221 426 428

405 628 668 48.1 64.3 61.1 187 416 398

406 596 635 47.1 70.9 58.9 195 421 369

403 572 550 49.5 67.0 62.0 203 381 334

27.2 59.2 65.2 4.69 2.14 2.84 22.1 41.3 35.6

GRO-Ga MAT-Gb MAT-Sb GRO-Ga MAT-Gb MAT-Sb GRO-Ga MAT-Gb MAT-Sb

0.225 0.423 0.041 0.018 0.652 0.397 0.050 0.265 0.028

0.303 0.100 0.488 0.135 0.539 0.091 0.053 0.176 0.641

289 375 445 47.7 61.2 55.9 136 229 242

255 387 445 42.7 61.8 49.9 107 239 218

258 400 417 35.6 54.0 49.5 86 232 199

258 375 395 34.3 62.6 48.4 95 234 188

256 365 347 36.8 58.6 52.7 99 213 178

17.9 38.9 41.9 6.10 2.99 3.39 16.2 24.0 20.6

a,b,c

Main effect animal type means without a common superscript letter differ (P < 0.05). Linear and Quadratic = effects of level of total dissolve salts in drinking water. 2 0-BRW = 100% fresh or tap water and 0% brackish water; 50-BRW = 50% fresh water and 50% brackish water; 100-BRW = 100% brackish water; LowSLW = 100-BRW plus 3450 mg/l NaCl; Mod-SLW = 100-BRW plus 6900 mg/l NaCl. 3 BW = body weight; DM = dry matter; OM = organic matter; NDF = neutral detergent fiber; ADF = acid detergent fiber. 4 AT = animal type. 1

those for DM and OM as expected given the fairly high level of fiber in the grass hay and no supplemental concentrate. The P values were very similar for NDF and ADF and in many instances were less than for corresponding DM and OM measures.

100-BRW treatment (quadratic P = 0.056), and for MAT-S values tended to decrease linearly as the TDS level in drinking water increased (P = 0.093). The P values for expressions relative to BW and BW0.75 were slightly lower. Total tract DM digestibility was not influenced by water treatment with MAT-G or MAT-S. Conversely, DM digestibility by GRO-G was affected by TDS level in drinking water linearly (P = 0.006) and quadratically (P = 0.046), with values decreasing as TDS increased and then increasing slightly from Low-SLW to Mod-SLW. As a consequence, digestible DM intake by GRO-G decreased linearly (P = 0.040) and changed quadratically (P = 0.031) as water TDS level increased, with the lowest value at 100-BRW and increasing values with increases in the TDS level of the Low- and Mod-SLW treatments. Moreover, digestible DM intake by MAT-G was numerically lowest at Mod-SLW (quadratic effect, P = 0.102) and by MAT-S tended to decrease linearly with increasing TDS level (P = 0.093). Effects for OM intake, digestibility, and intake of digestible OM were similar to those for DM, although in many cases P values were slightly lower. Notable ones are for both linear and quadratic effects of drinking water TDS level in intake of digestible OM and DE by MAT-G mainly because of relatively lower values with the Mod-SLW water treatment. Animal type and water treatment effects on N intake in g/day were also similar to those on DM and OM but not significant (Table 4). However, there was a tendency for animal type differences, with an overall P value of 0.052 and main effect means of 7.1, 8.8, and 10.2 g/ day for GRO-G, MAT-G, and MAT-S, respectively (SEM = 0.82). There was no overall animal type effect on N digestibility. Digested N intake was lowest among animal types (P < 0.05) for GRO-G. Water treatment effects on N digestibility and intake of digestible N were similar to those for DM and OM noted above. Differences among animal types and effects of water treatments on intake and digestion of NDF and ADF (Table 4) are in accordance with

3.7. Energy measures Urinary energy was lowest for GRO-G (P < 0.05) and similar between MAT-G and MAT-S (Table 5). Results for energy loss in ruminally emitted CH4, however, were slightly different. Methane energy for GRO-G was lower than for MAT-S (P < 0.05), tended to be lower than for MAT-G (P = 0.073), and was numerically less for MAT-G than for MAT-S (P = 0.136). For GRO-G, urinary energy tended to increase linearly as drinking water TDS concentration increased (P = 0.085), whereas for MAT-S values decreased and then increased, with a tendency for linear change (P = 0.078) and a quadratic effect (P = 0.040). The only water treatment effect on energy loss in ruminally emitted CH4 was increasing and then decreasing values for MAT-S as TDS level increased (quadratic P = 0.038). Intakes of ME were lowest among animal types for GRO-G (P < 0.05; Table 5). Conversely, overall ME intake in kJ/kg BW0.75 was not influenced by animal type (P = 0.077). For both GRO-G and MAT-G, ME intake in MJ/day decreased linearly (P = 0.025 and 0.035, respectively) as drinking water TDS level increased, and there was a similar trend for MAT-S (P = 0.065). However, the pattern of change differed, with values for MAT-G similar for water treatments except for a lower value for Mod-SLW. Conversely, values for GRO-B decreased with increasing TDS to 100-BRW and Low-SLW water treatments and then increased with the final increase in TDS with the Mod-SLW treatment (quadratic, P = 0.031). Intake of ME by MAT-S decreased fairly steadily with increasing water level of TDS. Differences and P 77

Small Ruminant Research 164 (2018) 70–81

H. Yirga et al.

Table 5 Effects of levels of brackish water and NaCl in drinking water on energy intake, digestion, and losses in growing Boer goat wethers and mature Boer goat and Katahdin sheep. Contrast P value1

Water treatment2

Item

AT3

Linear

Quadratic

0-BRW

50-BRW

100-BRW

Low-SLW

Mod-SLW

SEM

Digestion (MJ/day)

GRO-Ga MAT-Gb MAT-Sb GRO-Ga MAT-Gb MAT-Sb GRO-Ga MAT-Gab MAT-Sb

0.021 0.064 0.046 0.085 0.290 0.078 0.473 0.504 0.200

0.043 0.076 0.887 0.203 0.884 0.040 0.604 0.238 0.038

6.47 9.87 10.47 0.18 0.34 0.47 1.19 1.27 1.66

5.35 9.97 9.90 0.18 0.32 0.32 1.19 1.52 1.78

4.43 10.02 9.51 0.19 0.38 0.39 1.07 1.55 1.92

4.68 9.87 8.78 0.19 0.35 0.27 1.29 1.43 1.63

4.90 8.73 8.16 0.23 0.37 0.38 0.98 1.46 1.51

0.545 1.059 0.858 0.022 0.047 0.037 0.150 0.186 0.127

GRO-Ga MAT-Gb MAT-Sb GRO-G MAT-G MAT-S

0.025 0.025 0.065 0.014 0.023 0.045

0.031 0.149 0.959 0.030 0.162 0.927

5.10 8.26 8.34 519 458 384

3.98 8.13 7.80 402 458 361

3.17 8.10 7.20 321 441 328

3.20 8.10 6.87 319 449 317

3.69 6.90 6.27 363 381 289

0.536 0.893 0.799 54.5 34.2 33.2

GRO-Ga MAT-Gb MAT-Sc GRO-G MAT-G MAT-S GRO-Gb MAT-Gb MAT-Sa

0.147 0.810 0.519 0.107 0.735 0.409 0.048 0.037 0.042

0.545 0.829 0.102 0.629 0.856 0.063 0.006 0.147 0.555

4.53 7.53 8.92 459 421 412 0.56 0.73 −0.58

4.61 7.47 9.34 459 422 430 −0.63 0.66 −1.54

4.57 7.91 9.40 457 441 432 −1.40 0.18 −2.20

4.21 7.13 8.89 422 399 411 −1.01 0.96 −2.02

4.19 7.76 8.94 418 427 411 −0.51 −0.86 −2.67

0.283 0.554 0.347 22.1 13.6 16.3 0.576 0.534 0.645

Urinary (MJ/day)

Methane (MJ/day)

Metabolizable MJ/day

kJ/kg body weight0.75

Heat MJ/day

kJ/kg body weight0.75

Recovered (MJ/day)

a,b,c

Main effect animal type means without a common superscript letter differ (P < 0.05). Lin and Quadratic = effects of level of total dissolve salts in drinking water. 2 0-BRW = 100% fresh or tap water and 0% brackish water; 50-BRW = 50% fresh water and 50% brackish water; 100-BRW = 100% brackish water; LowSLW = 100-BRW plus 3450 mg/l NaCl; Mod-SLW = 100-BRW plus 6900 mg/l NaCl. 3 AT = animal type. 1

values for ME intake in kJ/kg BW0.75 were similar to those in MJ/day, but with a significant linear decrease for MAT-S as water TDS concentration increased (P 0.045). Heat energy in MJ/day ranked (P < 0.05) GRO-G < MATG < G < MAT-S and was not affected by water treatment (Table 5). Recovered energy was lower for MAT-S vs. GRO-G and MAT-G (P < 0.05), with values of GRO-G and MAT-G numerically different (P = 0.110). As noted above for ME intake in MJ/day, there were similar linear decreases for each animal type (P < 0.05). This was also true for the quadratic effect of TDS level for GRO-G (P = 0.006), with values increasing with increasing levels of NaCl addition to 100-BRW. The primary factor responsible for the linear effect of TDS level with MAT-G was the low value for Mod-SLW.

supplementation presumably would have limited growth of GRO-G with long-term feeding. 4.2. Ruminal fluid characteristics and blood constituent levels Relatively high ruminal pH at 4 h after feeding reflects the moderate to low nutritive value of hay and lack of concentrate supplementation. Decreasing ruminal pH in GRO-G wethers as the TDS level increased may have been because of decreasing digestibility. This also could have involved increasing ruminal digesta volume if it is assumed that digesta passage rate did not markedly vary among water treatments. Perhaps increasing water intake by MAT-G with increasing TDS level contributed to decreasing pH and ruminal ammonia N concentration. The increasing molar percentage of acetate in ruminal VFA and decreasing levels of propionate and butyrate as drinking water TDS level increased only occurred with GRO-G. This could relate to the linear effect of TDS level on total tract, and presumably ruminal digestibility, with this animal type. Some differences among animal types in plasma concentrations of minerals would be expected regardless of the diet being used. Differences among animal types in DM intake relative to BW probably contributed to the corresponding ranking in plasma urea N concentration. The lack of effect of water treatment on drinking water intake by GRO-G and MAT-S may explain numerical increases in plasma osmolality. This is in contrast to MAT-G that increased water intake with increasing TDS concentration. Relatedly, there was a low but significant correlation between drinking water intake relative to BW0.75 and plasma osmolality (r = −0.26; P = 0.029). There were some differences among animal types and water treatments in plasma enzyme levels, but values were within ranges

4. Discussion 4.1. Water and feed composition The composition of 100-BRW differed from that of brackish water obtained from the same well used by Tsukahara et al. (2016). This may have been because of differences in residence time of water in the aquifer, temperature, water table depth, recharge rate, etc. However, both experiments were conducted in the same part of the year, with the previous one 3 yr earlier in 2012. The composition of water from this well has not been monitored over time other than samples in these two experiments. Based on the composition analysis and RE, but without considering potential effects of drinking water with elevated levels of TDS, the nutritive value of grass hay used should have been adequate or nearly so for maintenance of all three animal types. The hay alone without 78

Small Ruminant Research 164 (2018) 70–81

H. Yirga et al.

experiment. Tsukahara et al. (2016) postulated that the negative effect of brackish water consumption on digestibility was because of adverse effects of high ruminal fluid osmolality on microbial activity. That may have been involved in findings of the present experiment as well. However, quadratic change in digestibility with increasing TDS level does not suggest that it was a simple matter of osmolality since increases in TDS achieved by NaCl addition did not depress digestibility beyond that of 100-BRW. It is unclear why digestibilities in GRO-G were negatively affected by consumption of water with an increasing TDS level and those by MAT-G and MAT-S were not. However, the most likely involved factor is higher nutrient and energy demands and potential for use by GRO-G that resulted in greater feed intake relative to BW and BW0.75. This suggests shorter ruminal digesta retention time and greater potential for adverse impact on digestion of influences of factors such as high osmolality on microbial activity. This is in accordance with common recommendations of lower allowable or tolerable levels of TDS in drinking water for young than older classes of ruminants. But as noted before, digestibilities for Low- and Mod-SLW not different or slightly greater than for 100-BRW suggest impact of water properties other than, or in addition to, osmolality. Water characteristics that changed with increasing TDS below but not above that of 100-BRW were hardness and concentrations of boron, calcium, magnesium, and sulfate. In this regard, the level of sulfate in 100-BRW could be considered moderate to high relative to common recommendations of maximum levels for ruminant livestock. For example, NRC (2007) recommended a maximum sulfate level in water of 2500 mg/l for ruminants consuming diets with at least 40% forage. Relatedly, Weeth and Hunter (1971) noted decreased intake of feed and water by beef heifers with water 5000 mg/l in sulfate. Adverse effects of high sulfate ingestion could involve ruminal microbial conversion to hydrogen sulfide and effects on the central nervous system (Suttle, 2010) or decreased availability of thiamin (Goetsch and Owens, 1987) or copper (NRC, 2007). However, it seems relatively more likely that such effects would impact feed intake rather than digestion. Moreover, safe and maximum upper levels of Ca in drinking water for beef cattle recommended by Socha et al. (2003) of 100 and 200 mg/l, respectively, are less than in 100-BRW. The magnesium concentration in 100-BRW was between the safe and maximum upper levels for beef cattle of 50 and 100 mg/l, respectively (Socha et al., 2003). Relatedly, NRC (1980) proposed a maximum boron level in livestock drinking water of 5 ppm, much less than in 100-BRW. Conversely, boron intake from water expressed relative to DM intake was considerably lower than the maximum tolerable level listed by NRC (2007). Another effect of the adverse impact of intake of water high in TDS on ruminal microbial activity in GRO-G wethers was on total tract N digestibility. Increasing ruminal outflow of potentially fermentable fiber would be expected to increase bacterial activity and growth in the hindgut, which would elevate fecal excretion of bacterial N (Ørskov, 1982; Goetsch and Owens, 1986a, 1986b). In support, the magnitudes of decline in total tract N digestibility with increasing TDS level were greater with increases from 0- to 50- and 100-BRW relative to those in OM. The same is true for increases from 100-BRW to Low- and ModSLW. Likewise, this would have increased N recycled to the hindgut concomitant with increasing bacterial N loss in feces. Relatedly, based on CP concentration in offered hay, apparent total tract N digestibility in goats of 52.1% is predicted with the equation of Moore et al. (2004). This value is much greater than observed for GRO-G with the 50- and 100-BRW and Low- and Mod-SLW treatments. The pattern of change in RE for GRO-G as TDS in drinking water increased was similar to that in ME intake; values were lowest for 100BRW and increasing slightly as the TDS level rose further to levels with Low- and Mod-SLW. The increases for Low- and Mod-SLW were partially attributable to numerically lower HE compared with 100-BRW (i.e., average difference of 0.37 MJ/day). As observed by Tsukahara et al. (2016), there were no indications of appreciable adverse effect of

considered normal for goats and sheep (Kaneko, 1989). Greater PCV and concentrations of hemoglobin and O2 for MAT-S than for goats agrees with recent trials in which Katahdin sheep wethers and Boer and Spanish goat wethers were compared (Mengistu et al., 2016, 2017). Elevated blood levels of enzymes such as ALP and AST can reflect a host of adverse conditions in many tissues (Bachman et al., 1992; Obeidat et al., 2005). Increasing TDS level in drinking water did not have any such effects in the present experiment. Factors responsible for decreasing levels of some enzymes in GRO-G as the TDS level in drinking water increased are unclear. 4.3. Water intake and losses The lack of effect of water treatment on drinking and total water intake by GRO-G agrees with findings of Tsukahara et al. (2016), although wethers in that study were slightly younger (6.6 months old at initiation) than in the present one. It is unclear why drinking and total water intake increased linearly with increasing TDS concentration for MAT-G and not for GRO-G or MAT-S. Relatedly, urinary water loss increased for each animal type with increasing TDS concentration in drinking water. But, this effect appeared due primarily to relatively high values of the Mod-SLW treatment for GRO-G and MAT-S. In the study of Tsukahara et al. (2016) with growing Boer and Spanish wethers, urinary water loss was greater with than without brackish water inclusion, and there was no effect of the level of brackish water. Drinking water intake in that study was similar among treatments. This suggests that there was less water loss by evaporation through respiration and sweating when brackish water was included in drinking water. This would not seem likely in the present experiment with GROG because water treatment did not influence the difference between total water intake and the sum of losses in urine and feces (368, 310, 387, 305, and 321 g/day; SEM = 53.4). This may also be the case for MAT-G based on a linear increase (P = 0.028) in apparent water balance with increasing TDS level (115, 326, 370, 295, and 391 g/day for 0-BRW, 50-BRW, 100-BRW, Low-SLW, and Mod-SLW, respectively; SEM = 72.1). Conversely, there was a tendency for a linear decrease (P = 0.099) with increasing TDS in water for MAT-S (534, 422, 341, 396, and 305 g/day for 0-BRW, 50-BRW, 100-BRW, Low-SLW, and Mod-SLW, respectively; SEM = 107.2), similar to the effect of brackish water inclusion in the study of Tsukahara et al. (2016). These results may involve differences among animal types in the potential for water retention in different sites, namely the gastrointestinal tract, plasma, interstitial fluid, and extracellular fluid. 4.4. Feed intake, digestion, and heat energy 4.4.1. Feed intake Relatively little effects of water treatment on feed intake by goats agrees with results of Tsukahara et al. (2016) with drinking water TDS levels up to 6900 mg/l. It appears that feed intake by sheep is more subject to adverse effects of increasing drinking water concentration of TDS. It is unclear if findings with the Low- and Mod-SLW water treatments achieved by NaCl addition to 100-BRW would have been similar if one or more natural saline water sources was consumed instead, or if another means was used to achieve higher TDS levels such as concentrating all minerals present in 100-BRW. 4.4.2. Growing Boer goat wethers Linear decreases in total tract digestibilities by GRO-G as drinking water TDS concentration increased is somewhat in accordance with findings of Tsukahara et al. (2016). In that previous study, brackish water inclusion at 33, 67, or 100% decreased digestibilities, but without impact of the level of brackish water. Factors responsible for this difference are unclear. Although, based on levels of NDF and CP in hay and total tract OM digestibility for the control or fresh water treatments, quality of hay probably was slightly higher in the previous 79

Small Ruminant Research 164 (2018) 70–81

H. Yirga et al.

Conflicts of interest

consumption of drinking water high in TDS on efficiency of energy metabolism.

There are no conflicts of interest. 4.4.3. Mature Boer goat wethers Numerically lowest intake and digestibility of OM by MAT-G among water treatments for Mod-SLW appeared largely responsible for linear effects of TDS level on ME intake and RE. But, it is important to note that this lowest RE value for MAT-G was considerably greater than many treatment means of GRO-G and MAT-S.

Acknowledgements The project was supported by the USDA National Institute of Food and Agriculture (NIFA) Evans-Allen ProjectsOKLXSAHLU2012, accession number 0228824, and OKLUSAHLU2017, accession number 1012650.

4.4.4. Mature Katahdin sheep wethers Measures necessary to conclusively discern why RE was lowest among animal types for MAT-S are not available. Some studies have suggested that sheep are less efficient than goats in recycling of N to the rumen (Alam et al., 1985; Domingue et al., 1991; Asmare et al., 2011, 2012). There is one measure in accordance with this possibility but others that are not. Lowest plasma urea N among animal types for MATS suggests that N recycling was less than for goats. This is based on regulation governed in part by the gradient of urea between plasma and the biofilm environment of urease-producing bacteria adhering to the ruminal wall (Cheng and Costerton, 1980). Conversely, ruminal ammonia N concentration at 4 h after feeding was not different among animal types, which does not indicate a greater deficiency of ruminally available nitrogenous compounds for MAT-S. Furthermore, digestibility was similar between MAT-G and MAT-S. Lastly, DM intake and digestible OM intake relative to BW (1.25, 1.06, and 0.80% BW for GRO-G, MAT-G, and MAT-S, respectively; SEM = 0.069) were lower for MAT-S than for GRO-G and MAT-G (P ≤ 0.021). These findings imply a higher ruminal ammonia N to fermentable OM ratio for MAT-S that appears to have resulted from lowest DM intake. As opposed to the treatment effects on digestibility with GRO-G, the linear decreases in ME intake and RE for MAT-S as water TDS level increased appeared largely attributable to the trend for decreasing hay intake. Factors responsible for this difference are unclear. It is notable that magnitudes of change in ME intake and RE were as great with increases in TDS due to NaCl addition as with increasing level of the brackish water source. This indicates that increasing osmolality may have contributed to effects with MAT-S in some manner, such as decreased gastrointestinal tract motility (Grovum, 1983). Moreover, safe and maximum upper drinking water levels of sodium (50 and 300 mg/l, respectively) and chlorine (100 and 300 mg/l, respectively) of Socha et al. (2003) are less than levels in 100-BRW. Thus, their increasing levels in drinking water with increasing TDS could have had influence as well.

References AOAC, 2006. Official Methods of Analysis, 18th edn. AOAC International, Gaithersburg, MD, USA. Alam, M.R., Poppi, D.P., Sykes, A.R., 1985. Comparative intake of digestible organic matter and water by sheep and goats. Proc. N. Z. Soc. Anim. Prod. 45, 107–111. Amundson, J.L., Mader, T.L., Rasby, R.J., Hu, Q.S., 2006. Environmental effects on pregnancy rate in beef cattle. J. Anim. Sci. 84, 3415–3420. Arieli, A., Naim, E., Benjamin, R.W., Pasternak, D., 1989. The effect of feeding saltbush and sodium chloride on energy metabolism in sheep. Anim. Prod. 49, 451–457. Asmare, A., Puchala, R., Tesfai, K., Detweiler, G.D., Dawson, L.J., Askar, A.R., Sahlu, T., Wang, Z., Goetsch, A.L., 2011. Effects of small ruminant type and restricted protein intake on metabolism. Small Rumin. Res. 98, 111–114. Asmare, A., Puchala, R., Tesfai, K., Detweiler, G.D., Dawson, L.J., Askar, A.R., Sahlu, T., Wang, Z., Goetsch, A.L., 2012. Effects of small ruminant type and level of intake on metabolism. Small Rumin. Res. 102, 186–190. Assad, F., El-Sherif, M.M.A., 2002. Effect of drinking saline water and feed shortage on adaptive responses of sheep and camels. Small Rumin. Res. 45, 279–290. Attia-Ismail, S.A., Abdo, A.R., Askar, A.R.T., 2008. Effect of salinity level in drinking water on feed intake, nutrient utilization, water intake and turnover and rumen function in sheep and goats. Egyptian J. Sheep Goat. Sci. 3, 77–92. Bachman, S.E., Galyean, M.L., Smith, G.S., Hallford, D.M., Graham, J.D., 1992. Early aspects of locoweed toxicosis and evaluation of a mineral supplement or clinoptilolite as dietary treatments. J. Anim. Sci. 70, 3125–3132. Broderick, G.A., Kang, J.H., 1980. Automated simultaneous determination of ammonia and total amino acids in rumen fluid and in vitro media. J. Dairy Sci. 63, 64–75. Brouwer, E., 1965. Report of sub-committee on constants and factors. In: Blaxter, K.L. (Ed.), Energy Metabolism, Proc. 3rd Symp. European Assoc. Anim. Prod. Publ. No. 11. Academic Press, London, UK, pp. 441–443. Castro, D.P.V., Yamamoto, S.M., Araújo, G.G.L., Pinheiro, R.S.B., Queiroz, M.A.A., Albuquerque, Í.R.R., Moura, J.H.A., 2017. Influence of drinking water salinity on carcass characteristics and meat quality of Santa Inês lambs. Trop. Anim. Health Prod. 49, 1095–1100. Cheng, K.-J., Costerton, J.W., 1980. Adherent rumen bacteria – their role in the digestion of plant material, urea and epithelial cells. In: Ruckebush, Y., Thivend, P. (Eds.), Digestive Physiology and Metabolism in Ruminants. AVI Publishing Co., Inc., Westport, CT, pp. 227–250. Domingue, B.M.F., Dellow, D.W., Barry, T.N., 1991. Voluntary intake and rumen digestion of a low-quality roughage by goats and sheep. J. Agric. Sci. 117, 111–120. Eisemann, J.H., Nienaber, J.A., 1990. Tissue and whole-body oxygen uptake in fed and fasted steers. Br. J. Nutr. 54, 399–411. Garrett, W.N., Mayer, J.H., Lofgreen, G.P., 1959. The comparative energy requirements of sheep and cattle for maintenance and gain. J. Anim. Sci. 18, 528–547. Goetsch, A.L., Owens, F.N., 1986a. Effects of dietary nitrogen level and ileal antibiotic administration on digestion and passage rates in beef heifers. I. High-concentrate diets. J. Anim. Sci. 62, 830–843. Goetsch, A.L., Owens, F.N., 1986b. Effects of dietary nitrogen level and ileal antibiotic administration on digestion and passage rates in beef heifers. II High-forage diets. J. Anim. Sci. 62, 844–856. Goetsch, A.L., Owens, F.N., 1987. Influence of supplemental sulfate (Dynamate®) and thiamin-HCl on passage of thiamin to the duodenum and site of digestion in steers. Arch. Anim. Nutr. 37, 1075–1083. Grovum, W.L., 1983. Integration of digestion and digesta kinetics with control of feed intake – a physiological framework for a model of rumen function. In: Gilchrist, F.M.C., Mackie, R.I. (Eds.), Herbivore Nutrition in the Subtropics and Tropics. The Science Press Ltd., Craighall, South Africa, pp. 244–268. Harper, G.S., King, T.J., Hill, B.D., Harper, C.M.L., Hunter, R.A., 1997. Effect of coal mine pit water on the productivity of cattle II. Effect of increasing concentrations of pit water on feed intake and health. Aust. J. Agric. Res. 48, 155–164. Hunter, A., Harper, G.S., McCrabb, G.J., 2002. The effect of coal mine pit water on the productivity of pregnant and lactating beef cows. Anim. Prod. Aust. 24, 105–108. Kaneko, J.J., 1989. Clinical Biochemistry of Domestic Animals, 4th edn. Academic Press, New York, NY, USA. Kil, W.Y., Dryden, G. McL., 2005. Effect of drinking saline water on food and water intake, food digestibility, and nitrogen and mineral balances of rusa deer stags (Cervus timorensis russa). Anim. Sci. 81, 99–105. Littell, R.C., Henry, P.R., Ammerman, C.B., 1998. Statistical analysis of repeated measures data using SAS procedures. J. Anim. Sci. 76, 1216–1231. Longeragan, G.H., Wagner, J.J., Gould, D.H., Garry, F.B., Thoren, M.A., 2001. Effects of water sulfate concentration on performance, water intake, and carcass characteristics of feedlot steers. J. Anim. Sci. 79, 2941–2948.

5. Conclusions Intake of ME and RE in growing Boer goat wethers were much more adversely affected by consumption of drinking water with increasing level of a brackish water source with a TDS level of 5596 mg/l compared with MAT-G and MAT-S, because of linear decreases in digestibilities. However, because additions of NaCl to the brackish water did not cause further declines in digestibility, ME intake, or RE, factors other than, or in addition to, osmolality in ruminal fluid appeared to have had influence. Mature Boer goat wethers were the only animal type to increase water consumption with increasing TDS concentration, and there were no deleterious effects other than slightly lower ME intake and RE for the brackish water source with the highest amount of added NaCl compared with other water treatments mainly because of numerical differences in intake and digestion. Mature Katahdin sheep wethers incurred linear decreases in ME intake and RE as the TDS level in water increased, inclusive of treatments with NaCl added to brackish water, mostly because of decreasing feed intake. Thus, effects of increasing TDS concentration in drinking water on digesta osmolality or other conditions such as ones associated with increasing Na and Cl intake might have had influence through effect on gut motility. 80

Small Ruminant Research 164 (2018) 70–81

H. Yirga et al.

M.J., 2015. Sources of variability in livestock water quality over 5 years in the Northern Great Plains. J. Anim. Sci. 93, 1792–1801. Puchala, R., Tovar-Luna, I., Goetsch, A.L., Sahlu, T., Carstens, G.E., Freetly, H.C., 2007. The relationship between heart rate and energy expenditure in Alpine, Angora, Boer and Spanish goat wethers consuming different quality diets at level of intake near maintenance or fasting. Small Rumin. Res. 70, 183–193. Puchala, R., Tovar-Luna, I., Sahlu, T., Freetly, H.C., Goetsch, A.L., 2009. The relationship between heart rate and energy expenditure in growing crossbred Boer and Spanish wethers. J. Anim. Sci. 87, 1714–1721. Sharma, A., Kundu, S.S., Tariq, H., Kewalramani, N., Yadav, R.K., 2017. Impact of total dissolved solids in drinking water on nutrient utilisation and growth performance of Murrah buffalo calves. Livest. Sci. 198, 17–23. Socha, M.T., Ensley, S.M., Tomlinson, D.J., Johnson, A.J., 2003. Variability of water composition and potential impact on animal performance. In: Proc. Intermt. Nutr. Conf. Salt Lake City, UT. Utah State Univ., Logan, UT, USA. Stanton, J.S., Dennehy, K.F., 2017. Brackish Groundwater and Its Potential to Augment Freshwater Suppliers: U.S. Geological Survey Fact Sheet 2017–3054. http://dx.doi. org/10.3133/fs20173054. Stanton, J.S., Anning, D.W., Brown, C.J., Moore, R.B., McGuire, V.L., Qi, S.L., Harris, A.C., Dennehy, K.F., McMahon, P.B., Degnan, J.R., Böhlke, J.K., 2017. Brackish Groundwater in the United States: U.S. Geological Survey Professional Paper 1833. http://dx.doi.org/10.3133/pp1833. Suttle, N.F., 2010. Mineral Nutrition of Livestock, 4th edn. CABI, Cambridge, MA, USA. Tsukahara, Y., Puchala, R., Sahlu, T., Goetsch, A.L., 2016. Effects of level of brackish and fresh water on forage intake, digestion, and energy utilization by Boer and Spanish goat wethers. J. Anim. Sci. 94, 3864–3874. USGS, 2013. National Brackish Groundwater Assessment. Info Sheet. U.S. Geological Survey. http://ne.water.usgs.gov/ogw/review/files/brackish_infosheet_v8.pdf. (Accessed 6 February 2016). Van Soest, P.J., Robertson, J.B., Lewis, B.A., 1991. Methods for dietary fiber, neutral detergent fiber and non-starch polysaccharides in relation to animal nutrition. J. Dairy Sci. 74, 3583–3597. Weeth, H.J., Hunter, J.E., 1971. Drinking of sulfate-water by cattle. J. Anim. Sci. 32, 277–281. Wilson, A.D., Dudzinski, M.L., 1973. Influence of the concentration and volume of saline water on the food intake of sheep: and on their excretion of sodium and water in urine and faeces. Aust. J. Agric. Res. 24, 245–256. Wilson, A.D., 1966. The tolerance of sheep to sodium chloride in food or drinking water. Aust. J. Agric. Res. 17, 503–514. Yousfi, I., Ben Salem, H., Aouadi, D., Abidi, S., 2016. Effect of sodiuim chloride, sodium sulfate or sodium nitrite in drinking water on intake, digestion, growth rate, carcass traits and meat quality of Barbarine lamb. Small Rumin. Res. 143, 43–52.

Lu, C.D., Potchoiba, M.J., Sahlu, T., Fernandez, J.M., 1990. Performance of dairy goats fed isonitrogenous diets containing soybean meal or hydrolyzed feather meal during early lactation. Small Rumin. Res. 3, 425–434. McGregor, B.A., 2004. Water Quality and Provision for Goats. A Report for the Rural Industries Research and Development Corporation. RIRDC publication, Barton, ACT, Australia. Mengistu, U.L., Puchala, R., Sahlu, T., Gipson, T.A., Dawson, L.J., Goetsch, A.L., 2016. Conditions to evaluate differences among individual sheep and goats in resilience to restricted drinking water availability. Small Rumin. Res. 144, 320–333. Mengistu, U.L., Puchala, R., Sahlu, T., Gipson, T.A., Dawson, L.J., Goetsch, A.L., 2017. Conditions to evaluate differences among individual sheep and goats in resilience to high heat load index. Small Rumin. Res. 147, 89–95. Moore, J.E., Goetsch, A.L., Luo, J., Owens, F.N., Galyean, M.L., Johnson, Z.B., Sahlu, T., Ferrell, C.L., 2004. Prediction of fecal crude protein excretion of goats. Small Rumin. Res. 53, 253–274. NRC, 1980. Mineral Tolerance of Domestic Animals. National Academy of Sciences, Washington, DC, USA. NRC, 2007. Nutrient Requirements of Small Ruminants. Sheep, Goats, Cervids, and New World Camelids. National Academy Press, Washington, DC, USA. Obeidat, B.S., Strickland, J.R., Vogt, M.L., Taylor, J.B., Krehbiel, C.R., Remmenga, M.D., Clayshulte-Ashley, A.K., Whittet, K.M., Hallford, D.M., Hernandez, J.A., 2005. Effects of locoweed on serum swainsonine and selected serum constituents in sheep during acute and subacute oral/intraruminal exposure. J. Anim. Sci. 83, 466–477. Ørskov, E.R., 1982. Protein Nutrition in Ruminants. Academic Press, New York, NY, USA. Paiva, G.N., de Araújo, G.G.L., Henriques, L.T., Medeiros, A.N., Filho, E.M.B., Costa, R.G., de Albuquerque, I.R.R., Gois, G.C., Campos, F.S., Freire, R.M.B., 2017. Water with different salinity levels for lactating goats. Semina: Ciências Agrárias, Londrina 38, 2065–2074. Peirce, A.W., 1957. Studies on salt tolerance of sheep. I. The tolerance of sheep for sodium chloride in the drinking water. Aust. J. Agric. Res. 8, 711–722. Peirce, A.W., 1959. Studies on salt tolerance of sheep. II. The tolerance of sheep for mixtures of sodium chloride and magnesium chloride in the drinking water. Aust. J. Agric. Res. 10, 725–735. Peirce, A.W., 1966. Studies on salt tolerance of sheep. VI. The tolerance of wethers in pens for drinking waters of the types obtained from underground sources in Australia. J. Agric. Res. 17, 209–218. Peirce, A.W., 1968a. Studies on salt tolerance of sheep. VII. The tolerance of ewes and their lambs in pens for drinking waters of the types obtained from underground sources in Australia. Aust. J. Agric. Res. 19, 577–587. Peirce, A.W., 1968b. Studies on salt tolerance of sheep. VII. The tolerance of grazing ewes and their lambs for drinking waters of the types obtained from underground sources in Australia. Aust. J. Agric. Res. 19, 589–595. Petersen, M.K., Muscha, J.M., Mulliniks, J.T., Waterman, R.C., Roberts, A.J., Rinella,

81