Evaluation of different dietary electrolyte balance in weanling pigs diets

Accepted Manuscript Title: Evaluation of different dietary electrolyte balance in weanling pigs diets Author: Xin Jian Lei Jing Young Chung Jae Hong Park In Ho Kim PII: DOI: Reference:

S0377-8401(16)31077-X http://dx.doi.org/doi:10.1016/j.anifeedsci.2017.02.014 ANIFEE 13731

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Please cite this article as: Lei, X.J., Chung, J.Y., Park, J.H., Kim, I.H.,Evaluation of different dietary electrolyte balance in weanling pigs diets, Animal Feed Science and Technology (2017), http://dx.doi.org/10.1016/j.anifeedsci.2017.02.014 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

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ance (dEB) on growth performance and nutrient digestibility in weanling pigs. •

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Average daily feed intake and average daily gain were optimized when pig fed diets with

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Highlights We evaluated effects of 4 levels (0, 83, 166, 250 mEq/kg of diet) of dietary electrolyte bal

dEB ranging from 166 to 250 mEq/kg. •

Pigs fed diets with dEB of 166 and 250 mEq/kg had greater apparent total tract digestibili

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ty of dry matter and nitrogen.

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Running head: dietary electrolyte balance in weanling pigs

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Evaluation of different dietary electrolyte balance in weanling pigs diets

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Xin Jian Lei, Jing Young Chung, Jae Hong Park, and In Ho Kim*

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Department of Animal Resource and Science, Dankook University, Cheonan, 330-714,

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Chungnam, South Korea

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* Corresponding author: In Ho Kim. Department of Animal Resource and Science, Dankook University, Cheonan, Chungnam,

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South Korea

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E-mail: [email protected]

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Tel: +82-41-550-3652

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Fax: +82-41-559-7881

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Abstract

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A total of 160 weanling pigs ((Duroc × Landrace) × Yorkshire; average initial weight of 7.67 ±

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0.97 kg, 28 ± 1 d of age) were allotted into 1 of 4 treatments to determine effects of dietary

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electrolyte balance (dEB, Na + K - C1 mEq/kg of the diet) on growth performance and nutrient

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digestibility. Pigs were fed 4 diets with different dEB levels: 0, 83, 166, and 250 mEq/kg of dEB

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for 4 weeks. Various dEB values were obtained by altering the concentrations of calcium

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chloride, calcium carbonate, and sodium bicarbonate. Pigs fed diets with dEB of 166 and 250

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mEq/kg exhibited greater average daily gain (ADG) than those fed 0 mEq/kg diet throughout the

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experiment (P < 0.05). During d 14 to 28 and d 0 to 28, the average daily feed intake (ADFI) was

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greater in 166 and 250 mEq/kg dietary treatments compared with 0 mEq/kg dietary treatment (P

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< 0.05). However, no difference was observed on gain to feed ratio between dietary treatments

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throughout the experiment (P > 0.05). 166 and 250 mEq/kg dietary treatments had greater

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apparent total tract digestibility (ATTD) of dry matter and nitrogen compared with 0 mEq/kg

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dietary treatment (P < 0.05). There was no effect on ATTD of gross energy between dietary

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treatments (P > 0.05). Taken together, these results suggested that weanling pigs obtained

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optimal growth performance and nutrient digestibility when fed diets with dEB in the range of

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166 to 250 mEq/kg.

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Keywords: dietary electrolyte balance; weanling pigs; growth performance; nutrient digestibility

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Abbreviations: ADFI, average daily feed intake; ADG, average daily gain; ATTD, apparent total t

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ract BW, body weight; dEB, dietary electrolyte balance; DM, dry matter; GE, gross energy; G:F,

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gain to feed ratio; mEq, milliequivalents; N, nitrogen

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1. Introduction Dietary electrolyte balance (dEB) has been reported to influence the acid base balance,

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growth performance, and nutrient digestibility in pigs (Haydon and West, 1990; Dersjant-Li et al.,

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2001b; Guzmán-Pino et al., 2015). Sodium (Na), potassium (K), and chloride (Cl) are the major

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dietary ions that affect dEB (NRC, 2012; Saravanan et al., 2013). Dietary electrolyte balance,

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under most circumstances, is suggested to be defined as milliequivalents (mEq) of Na plus K

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minus Cl ions (Mongin, 1981).

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Generally, a positive dEB level can optimize pigs’ growth, but a negative dEB may reduce

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feed intake (Patience et al., 1987; Dersjant-Li et al., 2001a). NRC (2012) reported that the

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optimal dEB for pigs is about 250 mEq/kg. However, discrepant results regarding the optimal

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dEB for pigs were observed in previous studies. Guzmán-Pino (2015) suggested that pigs

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obtained optimal growth rate when fed with diets containing dEB ranging from -16 to 133

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mEq/kg. Dersjant-Li et al. (2001a) observed the optimal dEB for pigs could be between 200 and

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500 mEq/kg. Additionally, Budde and Crenshaw (2003) found that growth performance were not

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affected by different dEB levels (-35, 112, and 212 mEq/kg). The objective of this experiment,

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therefore, was to investigate effects of 4 levels (0, 83, 166, 250 mEq/kg of diet) of dEB on

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growth performance and nutrient digestibility of weanling pigs.

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2. Material and methods

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The experimental protocol used in this study was approved by the Animal Care and Use

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Committee of Dankook University.

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2.1. Experimental Design, Animals, and Housing

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One hundred and sixty weanling pigs [(Yorkshire × Landrace) × Duroc] with an average

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initial body weight (BW) of 7.67 ± 0.97 kg were randomly allotted into 1 of 4 dietary treatments

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with 10 replicates of 4 pigs (2 gilts and 2 barrows) each, according to initial BW and sex. The

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dietary treatments included 4 levels of dEB (0, 83, 166, and 250 mEq/kg) with similar nutritional

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levels. The dEB was calculated using the formula as: dEB (mEq/kg) = Na mEq/kg + K mEq/kg −

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Cl mEq/kg (Mongin, 1981). All diets were formulated to meet or exceed the nutrient

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requirements established by the NRC (2012). Sodium bicarbonate (NaHCO3), calcium chloride

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(CaCl2), and calcium carbonate (CaCO3) were used to obtain the required dEB. Diet composition

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and nutrient contents of the experimental diets are presented in Table 1. Diets were fed in 2

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phases during the 28-d feeding trial, including phase I (d 0 to 14) and phase II (d 14 to 28).

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Before starting the experiment, the diets were analyzed for Na, K and Cl contents to calculate the

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exact dEB. Na and K (method 985.01) were determined according to AOAC (2007) procedures,

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and Cl was determined by the method described by Lacroix et al. (1970). Diets were offered in

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meal form throughout the experiment. Pigs were allowed ad libitum access to the experimental

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diets and water at all times. All pigs were housed in an environmentally controlled room with

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forced ventilation and completely slatted plastic flooring. Each pen was equipped with a nipple

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drinker and a metal feeder. The initial room temperature was maintained at 31°C and then

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gradually decreased by 1°C every week.

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2.2. Sampling and Measurements

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Individual pig weight and feed consumption on a pen basis were recorded on d 0, 14, and 28.

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Average daily gain (ADG), average daily feed intake (ADFI), and gain to feed ratio (G:F) were

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calculated accordingly.

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To estimate the apparent total tract digestibility (ATTD) of dry matter (DM), nitrogen (N),

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and gross energy (GE), pigs were offered diets supplemented with chromic oxide (0.2%) as an

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indigestible marker from d 8 to 14 and d 22 to 28. On d 14 and 28, fecal samples were collected

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from all pens via rectal massage. Fecal samples from the same pen were pooled and mixed

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immediately, after which samples were stored at –20°C until subsequent analysis were conducted.

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For chemical analysis, fecal samples were oven-dried at 60°C for 72 h, after which diets and

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feces were ground to pass through a 1.0-mm screen for analysis of DM (Method 930.15) and N

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(method 984.13) using the AOAC (2007) procedures. Gross energy was determined by

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measuring the heat of combustion in the samples, using a bomb calorimeter (Parr 6100; Parr

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instrument Co., Moline, IL, USA). Chromium was analyzed via UV absorption

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spectrophotometry (UV-1201, Shimadzu Corp., Kyoto, Japan), according to the method

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described by Williams et al. (1962). The ATTD was then calculated using the following formula:

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ATTD (%) = [1-{(Nf × Cd)/(Nd × Cf)}] × 100,

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where Nf = nutrient concentration in feces (% DM), Nd = nutrient concentration in diet (%

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DM), Cd = chromium concentration in diet (% DM), and Cf = chromium concentration in feces

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(% DM).

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2.3. Statistical analyses

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All data were analyzed using the General Linear Model procedure of SAS (SAS Institute

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Inc., Cary, NC, USA). The pen was used as the experimental unit. Differences between

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treatments were detected by Tukey’s multiple range test. The data were presented as means and

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pooled standard error of the mean. Significance was defined as P < 0.05.

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3. Results

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3.1. Growth performance Performance data for weanling pigs fed diets with different dEB are summarized in Table 2.

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During d 0 to 14, a greater (P < 0.05) ADG was achieved for pigs receiving 166 and 250 mEq/kg

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diets when compared with that pigs fed 0 mEq/kg diet, whereas no significant difference was

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detected on ADFI (P > 0.05). During d 14 to 28, ADG and ADFI were greater (P < 0.01) in pigs

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fed 166 and 250 mEq/kg diets as compared with pigs fed 0 mEq/kg diet. Pigs fed 166 mEq/kg

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diet had greater ADG and ADFI compared with those fed 0 mEq/kg diet during d 0 to 28 (P <

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0.05). However, G:F was not affected by changing dEB throughout the experiment (P > 0.05).

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3.2. Nutrient digestibility

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The effects of dEB levels on nutrient digestibility are presented in Table 3. On d 14 and 28,

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the ATTD of DM and N for pigs fed diets with dEB of 166 and 250 mEq/kg were greater (P

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<0.05) than pigs fed the diet with dEB of 0 mEq/kg. On d 14, pigs fed diet with dEB of 83

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mEq/kg had greater (P <0.05) ATTD of DM and N compared with those fed diet with dEB of 0

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mEq/kg. Additionally, on d 14, compared with 250 mEq/kg diet pigs, pigs fed 166 mEq/kg diet

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showed greater (P < 0.05) ATTD of N. However, there was no difference in the ATTD of GE

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among dietary treatments (P > 0.05).

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4. Discussion

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This study was designed to determine effects of different dEB values (ranging from 0 to 250

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mEq/kg) in weanling pigs. Different dEB was achieved through addition of different amounts of

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calcium chloride, calcium carbonate, and sodium bicarbonate. Austic (1983) indicated that pigs

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showed optimal growth performance when dEB ranging from 100 to 300 mEq/kg. Patience et al.

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(1987) compared diets that varied in dEB (-85, 0, 100, 175, 277, 341 mEq/kg) to determine the

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optimal dEB for growing pigs. Finally, they observed that pigs fed diet with a dEB around 175

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mEq/kg obtained optimal growth performance. The results of the study of Dersjant-Li et al.

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(2001a) suggested that optimal dEB for young pigs (5 to 10 weeks of age) was between 200 and

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500 mEq/kg. In agreement with these previous studies, our findings showed that the growth of

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pigs was affected by different dEB. Pigs fed diets with dEB of 166 and 250 mEq/kg obtained

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greater ADG throughout the experiment and greater ADFI during d 14 to 28 and d 0 to 28

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compared with those fed diets with dEB of 0 mEq/kg, although G:F was not affected by dietary

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treatment. In the present study, calcium carbonate was replaced by calcium chloride to reduce

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dEB value and maintain the same calcium concentration in the diets. Carnes (1977) and Yen et al.

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(1981) observed that addition of calcium chloride decreased growth rate and feed intake in pigs.

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Additionally, supplementation of calcium chloride may suppress appetite thereby reducing feed

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intake. Therefore, the depression in growth performance in 0 mEg/kg diet may be due to the

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addition of calcium chloride resulted in metabolic acidosis. Nevertheless, the optimal dEB for

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pigs in the literature is inconsistent. Haydon et al. (1990) observed that increasing dEB (25, 100,

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175, 250, 325, or 400 mEq/kg) for growing pigs linearly increased ADFI and ADG, whereas

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feed efficiency was not affected. However, in finisher phase, ADFI was linearly increased with

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the increase of dEB, but ADG and feed efficiency were unaffected by dEB. Guzmán-Pino et al.

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(2015) observed that piglets fed low dEB diets between -16 to 133 mEq/kg had better growth

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performance compared with piglets fed high dEB diets (ranging from 269 to 388 mEq/kg). In a 3

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days feeding trial, Edwards et al. (2010) reported that 121 or 375 mEq/kg of diets did not

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affected growth performance of finishing pigs. Patience and Chaplin (1997) found pigs fed -20

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mEq/kg diet tended to grow faster than pigs fed 104 and 163 mEq/kg diets, but feed intake and

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feed efficiency were not affected. The discrepancy between different studies about the optimal

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dEB may be due to composition of diet, growth phase of pigs, and duration of the study. Haydon and West (1990) evaluated various dEB (-50, 100, 250, and 400 mEq/kg) on

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digestibility of DM, GE, and N in growing pigs. The results indicated that ATTD of DM, GE,

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and N were not affected by different dEB values. Guzmán-Pino et al. (2015) observed that pigs

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fed 16 and 133 mEq/kg diets had higher apparent CP digestibility than pigs fed 269 mEq/kg diet.

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In the present study, the ATTD of DM and N was higher in pig fed 166 mEq/kg diet compared

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with those fed diets with dEB of 0 or 83 mEq/kg. Meanwhile, pigs fed diet with dEB of 250

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mEq/kg showed higher ATTD of DM and N than pigs fed 0 mEq/kg diet. The improvement of

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ATTD of DM and N may help to explain the better performance in pigs fed diet with 166 and

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250 mEq/kg.

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5. Conclusion

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In conclusion, the results indicated that dEB values ranging from 166 to 250 mEq/kg

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allowed pigs to obtain optimal growth and better ATTD of DM and N.

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Reference

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Austic, R.E., Boyd, R.D., Klasing, K.C., Riley, W.W., 1983. Effect of dietary electrolyte balance

180 181 182

on growth performance in swine. J. Anim. Sci. 57(Suppl. 1), 236 (Abstr.).

AOAC. 2007. Official methods of analysis of AOAC International. 18th ed. AOAC International, Gaithersburg, MD.

183

Budde, R.A. Crenshaw, T.D., 2003. Chronic metabolic acid load induced by changes in dietary

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electrolyte balance increased chloride retention but did not compromise bone in

185

growing swine. J. Anim. Sci. 81,197–208.

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Carnes, L.W., 1977. Methods of Controlling Feed Intake of Gestating Sows. University of Arkansas, Fayetteville (M.S. Thesis). Dersjant-Li, Y., Schulze, H., Schrama J.W., Verreth, J.A., Verstegen, M.W.A., 2001a. Feed intake,

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growth, digestibility of dry matter and nitrogen in young pigs as affected by dietary

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cation-anion difference and supplementation of xylanase. J. Anim. Physiol. Anim. Nutr.

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85, 101–109.

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Dersjant-Li, Y., Schulze, H., Zandstra, T., Boer, H., Schrama J.W., Verreth, J.A.J., 2001b.

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Performance, digesta characteristics, nutrient flux, plasma composition, and organ

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weight in pigs as affected by dietary cation anion difference and nonstarch

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polysaccharide. J. Anim. Sci. 79, 1840–1848.

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Edwards, L.N., Engle, T.E., Paradis, M.A., Correa, J.A., Anderson, D.B., 2010. Persistence of

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blood changes associated with alteration of the dietary electrolyte balance in

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commercial pigs after feed withdrawal, transportation, and lairage, and the effects on

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Haydon, K.D., West, J.W., 1990. Effect of dietary electrolyte balance on nutrient digestibility

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determined at the end of the small intestine and over the total digestive tract in growing

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pigs. J. Anim. Sci. 68, 3687–3693.

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performance and carcass quality. J. Anim. Sci. 88, 4068–4077

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Guzmán-Pino, S.A., Solà-Oriol, D., Davin R., Manzanilla, E.G., Pérez, J.F., 2015. Influence of

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dietary electrolyte balance on feed preference and growth performance of postweaned

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piglets. J. Anim. Sci. 93, 2840–2848.

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Haydon, K.D., West, J.W., McCarter M.N., 1990. Effect of dietary electrolyte balance on

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performance and blood parameters of growing-finishing swine fed in high ambient

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temperatures. J. Anim. Sci. 68:2400–2406.

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tissue extracts using the chloride ion electrode. Commun. Soil Sci. Plant Anal. 1, 1-6. Mongin, P., 1981. Recent advances in dietary cation–anion balance: applications in poultry. Proc.

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LaCroix, R.L., Keeney, D.R., Walsh, L.M., 1970. Potentiometric titration of chloride in plant

Nutr. Soc. 40, 285–294.

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NRC, 2012. Nutrient Requirements of Swine, 11th rev. ed. Natl. Acad. Press, Washigton, DC.

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O’Shea, C.J., McAlpine, P., Sweeney, T., Varley, P.F., O’Doherty, J.V., 2014. Effect of the

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interaction of seaweed extracts containing laminarin and fucoidan with zinc oxide on

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the growth performance, digestibility and faecal characteristics of growing piglets. Br. J

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Nutr. 111, 798–807.

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Patience, J.F., Chaplin, R.K., 1997. The relationship among dietary undetermined anion, acidbase balance, and nutrient metabolism in swine. J. Anim. Sci. 75, 2445–2452.

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Patience, J.F., Austic R.E., Boyd, R.D., 1987. Effect of dietary electrolyte balance on growth and acid-base status in swine. J. Anim. Sci. 64, 457–466.

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Saravanan, S., Geurden, I., Orozco, Z.G.A., Kaushik, S.J., Verreth, J.A.J., Schrama, J.W., 2013.

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Dietary electrolyte balance affects the nutrient digestibility and maintenance energy

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225 226

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expenditure of Nile tilapia. Brit. J. Nutr. 110, 1948–1957.

Williams, C.H., David, D.J., Iismaa, O., 1962. The determination of chromic oxide in faeces samples by atomic absorption spectrophotometry. J. Agric. Sci. 59, 381–385. Yen, J.T., Pond, W.G., Prior, R.L., 1981. Calcium chloride as a regulator of feed intake and weight gain in pigs. J. Anim. Sci. 52, 778–782.

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Table 1

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Ingredient and chemical composition of the experimental diets (as-fed basis) d 14 to 28 dEB, mEq/kg of diet 83 166 250

58.1

58.1

58.1

50.0

50.0

50.0

50.0 200.0 30.0 7.0

50.0 200.0 30.0 7.0 -

331.4 150.0 50.0 50.0 20.0

326.4 150.0 50.0 50.0 20.0

331.4 150.0 50.0 50.0 20.0

326.4 150.0 50.0 50.0 20.0

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286.5 100.0 50.0 100.0 20.0

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291.5 100.0 50.0 100.0 20.0

0

150.0

150.0

150.0

150.0

50.0

50.0

50.0

50.0

30.0 100.0 30.0 7.0

30.0 100.0 30.0 7.0

30.0 100.0 30.0 7.0 -

30.0 100.0 30.0 7.0 -

4.0

4.0

4.0

4.0

4.0

4.0

3.0 -

3.0 5.0

3.0 -

3.0 5.0

3.0 -

3.0 5.0

3.4

3.4

3.4

1.9

1.9

1.9

1.9

7.3 2.5 8.2

7.3 2.5 8.2

7.3 2.5 8.2

4.2 1.0 2.5

4.2 1.0 2.5

4.2 1.0 2.5

4.2 1.0 2.5

5.0

5.0

5.0

5.0

5.0

5.0

5.0

5.0 5.0

5.0 5.0

5.0 5.0

5.0 5.0

5.0 5.0

5.0 5.0

5.0 5.0

2467 188.3 7.6 5.6 51.4 18.9 15.0 6.4 8.9

2479 188.7 7.7 5.7 51.6 19.0 15.0 6.4 9.0

2467 188.3 7.7 5.6 51.4 18.9 15.0 6.4 8.9

2468 170.0 6.8 5.2 51.1 23.4 13.5 5.0 8.1

2456 169.6 6.8 5.2 50.9 23.3 13.5 5.0 8.1

2468 170.0 6.9 5.2 51.1 23.4 13.5 5.0 8.1

2456 169.6 6.9 5.2 50.9 23.3 13.5 5.0 8.1

4.0

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50.0 200.0 30.0 7.0 -

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286.5 100.0 50.0 100.0 20.0

3.0 5.0

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Item Ingredients, g/kg Corn 291.5 Wheat 100.0 Barley 50.0 Rice 100.0 Oat hull 20.0 Soybean meal, 440 g 58.1 CP/kg Fermented soybean 50.0 meal, 560 g CP/kg Fish meal, 620 g CP/kg 50.0 Whey powder 200.0 Lard 30.0 Calcium carbonate Calcium chloride 7.0 Monocalcium 4.0 phosphate Salt 3.0 Sodium bicarbonate DL-Methionine, 990 3.4 g/kg L-Lysine·HCl, 780 g/kg 7.3 Threonine, 985 g/kg 2.5 Tryptophan, 100 g/kg 8.2 Vitamin and mineral 5.0 premix2 Bioplus 2B3 5.0 VevoVital4 5.0 Calculated composition, g/kg Net energy, kcal/kg 2479 Crude protein 188.7 Calcium 7.6 Total phosphorus 5.7 Ether extract 51.6 Crude fiber 19.0 SID5 lysine 15.0 SID methionine 6.4 SID threonine 9.0

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d 0 to 14 dEB , mEq/kg of diet 0 83 166 250 1

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231 232 233 234 235 236 237 238 239 240 241 242

SID tryptophan 2.7 2.7 2.7 2.7 2.4 2.4 2.4 2.4 SID methionine and 9.0 9.0 9.0 9.0 8.1 8.0 8.1 8.0 cysteine Analyzed composition, g/kg Sodium 3.0 4.5 3.4 4.9 1.9 3.5 2.1 3.7 Chloride 13.3 13.2 8.4 8.1 10.7 10.5 5.8 5.6 Potassium 9.8 10.1 10.3 10.2 9.0 8.9 9.2 9.4 dEB, mEq/kg 7.1 82.8 162.2 246.4 12.0 84.6 163.8 244.1 1 dEB, dietary electrolyte balance. 2 Provided per kg of complete diet: vitamin A, 11,025 IU; vitamin D3, 1,103 IU; vitamin E, 44 IU; vitamin K, 4.4 mg; riboflavin, 8.3 mg; niacin, 50 mg; thiamine, 4 mg; D-pantothenic, 29 mg; choline, 166 mg; vitamin B12, 33 µg; Fe (as FeSO4 • 7H2O), 80 mg; Cu, (as CuSO4•5H2O), 12 mg; Zn (as ZnSO4), 85 mg; Mn (as MnO2), 8 mg; I (as KI), 0.28 mg; Se (as Na2SeO3•5H2O), 0.15 mg. 3 Bioplus 2B®, a mixture containing of 3.2 × 109 viable spores/g Bacillus licheniformis (DSM 5749) and Bacillus subtilis (DSM 5750) in equal with a minimum of 3.2 x 109 CFU g-1 of the product, Chr. Hansen A/S，Horsholm, Denmark. 4 Vevovital®, 100% benzoic acid, DSM Nutritional Products, Ltd., The Netherlands. 5 SID, standard ileal digestible basis.

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Table 2

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The effects of different dietary electrolyte balance (dEB) on growth performance in weanling pigs

245

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dEB, mEq/kg of diet 83 166

P-value 0.039 0.120 0.694

<0.001 0.003 0.332

d

<0.001 0.002 0.901

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246 247 248 249

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0 250 Item SEM1 d 0 to 14 ADG2, g 297b 306ab 333a 326a 9.2 2 376 379 426 403 15.6 ADFI , g 2 G:F 0.788 0.811 0.783 0.810 0.021 d 14 to 28 ADG, g 522c 541bc 578a 562ab 7.2 b ab a a 806 852 847 15.6 ADFI, g 768 G:F 0.681 0.672 0.678 0.664 0.007 d 0 to 28 ADG, g 409c 423bc 455a 444ab 6.5 c bc a ab ADFI, g 572 592 639 625 11.7 G:F 0.716 0.715 0.712 0.710 0.004 a,b,c Means in the same row with different superscripts differ (P < 0.05). 1 Pooled standard error of mean. 2 ADG, average daily gain; ADFI, average daily feed intake; G:F, gain to feed ratio.

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249

81.25ab 80.42b 81.28

76.33c 75.95b 78.58

77.08bc 76.42b 77.89

79.63a 78.52a 78.46

78.85ab 77.81a 78.13

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82.12a 82.54a 81.03

0.45 0.46 0.60

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80.00b 80.46b 80.51

P-value

0.57 0.81 0.71

<0.001 <0.001 0.855 <0.001 <0.001 0.569

The effects of different dietary electrolyte balance (dEB) on apparent total tract digestibility in weanling pigs. a,b,c Means in the same row with different superscripts differ (P < 0.05). 1 Pooled standard error of means.

an

253 254 255

78.56c 77.23c 80.92

SEM1

M

252

250

d

251

0

dEB, mEq/kg of diet 83 166

Ac ce pt e

250

Item d14 Dry matter, % Nitrogen, % Gross energy, % d 28 Dry matter, % Nitrogen, % Gross energy, % Table 3

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