Stylosanthes cv. Campo Grande silage with or without concentrate in sheep diets: Nutritional value and ruminal fermentation

Accepted Manuscript Title: Stylosanthes cv. Campo Grande silage with or without concentrates in sheep diets: Nutritional value and ruminal fermentation Author: T.C. da O.G. Pereira M.C.N. Agarussi V.P. da Silva L.D. da Silva L.L. Cardoso K.G. S.C. Valadares PII: DOI: Reference:

S0921-4488(15)00113-3 http://dx.doi.org/doi:10.1016/j.smallrumres.2015.03.011 RUMIN 4915

To appear in:

Small Ruminant Research

Received date: Revised date: Accepted date:

19-12-2014 11-3-2015 12-3-2015

Please cite this article as: da, T.C., Agarussi, M.C.N., da Silva, V.P., da Silva, L.D., Cardoso, L.L., Valadares, S.C.,Stylosanthes cv. Campo Grande silage with or without concentrates in sheep diets: nutritional value and ruminal fermentation, Small Ruminant Research (2015), http://dx.doi.org/10.1016/j.smallrumres.2015.03.011 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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Highlights

2 Stylosanthes silage (SS) has lower intake and digestibility than corn silage

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Corn silage (CS) and SS are nutritionally similar in diets containing concentrate (C)

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The microbial protein synthesis is similar between the SS and CS diets with C

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Stylosanthes silage is recommended for use in sheep diets containing C

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Stylosanthes cv. Campo Grande silage with or without concentrates in sheep diets:

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nutritional value and ruminal fermentation

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T.C. da Silvaa, O.G. Pereiraa,, M.C.N. Agarussia, V.P. da Silvaa, L.D. da Silvaa, L.L.

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Cardosoa, K.G. Ribeiroa, S.C. Valadares Filhoa

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a

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Brazil.

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[email protected]

[email protected],

[email protected],

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[email protected],

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Animal Science Department, Federal University of Vicosa, Vicosa 36570-000, MG,

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Abstract

Intake and apparent digestibility of nutrients, ruminal ammonia concentration,

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ruminal pH, and microbial protein synthesis were evaluated in sheep fed diets

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containing Stylosanthes cv. Campo Grande silage (StS) or corn silage (CS) with and

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without concentrate [C; 40% of the dry matter (DM)]. Four sheep with an average initial

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body weight of 41 ± 2.68 kg were used and were distributed in a 4 × 4 Latin square

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design, arranged in a 2 × 2 factorial scheme. The SS diets with C showed similar intake

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of DM and total digestible nutrients (TDN) (P > 0.05) in comparison with CS diet with

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C. However, in the diets without the concentrate, SS showed lower intake of TDN than

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CS (P < 0.05). The digestibility of organic matter (OM) did not differ between the SS

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and CS in the diets with C (P > 0.05). The efficiency of microbial protein synthesis was

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also similar (P > 0.05) between the SS and CS diets with C (59.13 and 66.11 g CP/kg

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

Corresponding author. Av. P.H. Rolfs, sn, Centro, Viçosa-Minas Gerais, 36570-000 Tel.: +55 31 3899 3323; fax: +55 31 3899 2275. E-mail address: [email protected] (O.G. Pereira). 2

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TDN, respectively). The Stylosanthes cv. Campo Grande silage is a suitable roughage

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source to feed sheep, in diets containing 40% concentrate in the total DM.

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Keywords: intake, microbial protein synthesis, digestibility, tropical legumes

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1. Introduction

Forage legumes have been used to feed goats and sheep in tropical regions,

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mainly as pasture or conserved as hay (Mupangwa et al., 2000; Bamikole et al., 2009;

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Foster et al., 2009). Recently, interest in legume silage for livestock systems has

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increased in tropical countries, including Brazil (Heinritz et al., 2011; Souza et al.,

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2014). Among tropical legumes, Stylosanthes spp. has been used in diets for sheep and

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goats (Mupangwa et al., 2000; Hue et al., 2008). In Brazil, promising results have been

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obtained with the production of Stylosanthes cv. Campo Grande silage (StS),

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considering the fermentation profile, the intake and performance of beef cattle (Souza et

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al., 2014). Therefore, it is important to evaluate the potential use of StS in the sheep

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diets, given the limited amount of information available about this type of feed for

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ruminants.

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Stylosanthes silage was therefore hypothesized to have similar levels of intake,

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digestibility and ruminal fermentation to corn silage in diets with 40% concentrate. The

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intake and digestibility of nutrients, ammonia concentration and ruminal pH and

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microbial protein production were evaluated in sheep fed diets containing StS or corn

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silage (CS) with and without addition of concentrate.

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2. Materials and Methods

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2.1. Experimental location and climatic conditions

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The experiment was conducted at the Laboratory of Animals, and the chemical

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analysis were performed at the Forage Crops Laboratory from the Animal Science

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Department of Federal University of Vicosa [Universidade Federal de Viçosa (UFV)],

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located in Vicosa, Minas Gerais, Brazil. The city of Vicosa has a mean altitude of 648

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m, latitude 20°45'14" south and longitude 42°52'55" west. According to the Köppen

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classification, the climate is Cwa, a humid subtropical climate with coldest monthly

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temperatures above 18 ◦C; annual average rainfall between 1400 and 1600 mm and with

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rainy summers and dry winters.

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2.2. Experimental diets and silages

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The Stylosanthes cv. Campo Grande (Stylosanthes capitata plus Stylosanthes

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macrocephala) and the corn (Zea mays) were harvested at the pre-blooming stage and

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one -third milk-line respectively. The crops were chopped using a stationary chopper (2

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mm theoretical chop length). and packed in laboratory-scale silos with capacity of 550

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kg and packing density of 550 kg/m3. The treatments consisted of diets containing

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Stylosanthes cv. Campo Grande silage (StS) and corn silage (CS) with or without

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concentrate (C), which was included at a proportion of 40% of the dry matter (DM) of

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the diets. Diets were formulated according to the NRC (2007) (Table 1).

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2.3. Animals, handling, measurement and sample collection

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The animal handling and treatment were performed in accordance with the

guidelines and recommendations of the Animal Ethics Committee from UFV. Four crossbred sheep (predominantly Santa Ines breed) rumen-cannulated were

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used with an average initial weight of 41 ± 2.68 kg. The animals were housed in a

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covered barn in individual cages equipped with feeders and drinking water systems.

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Each experimental period lasted 15 days, with 10 days for adaptation and five

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days for collect samples and data. The animals were weighed at the beginning and at the

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end of each experimental period. The total collections of orts, feces and urine for four

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days of each period were used to estimate the digestibility of the nutrients.

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Urine collection was performed using collector funnels that were attached to the

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cages and drained into a bucket on the ground containing 100 mL of 20% (v./v.) sulfuric

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acid to prevent the loss of nitrogen. After 24 hours of collection, the weight and the total

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volume of urine were recorded, and an aliquot of 5% of the daily volume was removed

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and stored in a freezer. A composite sample was made for each animal after four days of

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collection. This composite sample was then homogenized, and a 10-mL sample was

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collected, which was then mixed with 40 mL of 0.036 N sulfuric acid (H2SO4) to

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prevent bacterial destruction of urinary purine derivatives and precipitation of uric acid.

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The samples were stored at -15ºC for subsequent laboratory analysis.

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To determine the pH and ammonia concentration in the ruminal fluid, samples

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were taken on the last day of each period, just prior to feeding and 2, 4 and 6 hours after

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feeding. Approximately 50 mL of rumen fluid was collected through the rumen cannula,

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and the pH of the fluid was immediately determined using a digital pH meter. After

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measuring the pH, 1 mL of a 50% H2SO4 (v./v.) solution was added to each sample to

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determine the concentration of ammonia in the sample.

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2.5. Chemical analyses

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At the end of each experimental period, samples of the feed, orts and feces were

thawed, dried at 55°C for 72 h and ground in a Wiley mill with a 1-mm sieve.

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The analyses were performed according to AOAC standards (1990) for

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determining the DM (method 934.01), organic matter (OM; method 930.05), CP 5

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(method 981.10) and ether extract (EE; method 920.39). The neutral detergent fiber

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(NDF) was determined by thermostable amylase and was corrected for ash using the

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techniques described by Mertens (2002). The NDF correction for nitrogenous

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compounds and estimates of neutral detergent insoluble nitrogen (NDIN) were based on

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the method of Licitra et al. (1996). Lignin analyses were only performed on the samples

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from the ingredients of the diets, using the method of cellulose solubilization in sulfuric

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acid (Van Soest and Robertson, 1985) and the acid detergent fiber (ADF) method based

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on the work of Goering and Van Soest (1967). The ammonia concentration in the

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ruminal fluid samples was determined to according Chaney and Marbach (1962). The

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concentration of non-fibrous carbohydrates (NFC) in the diet containing urea was

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calculated based on Detmann and Valadares Filho (2010).

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The analyses of allantoin, uric acid, xanthine and hypoxanthine in urine were

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performed using the colorimetric methods described by Chen and Gomes (1992). The

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absorbed purines (mmol/day) were calculated based on the excretion of purine

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derivatives, and the ruminal synthesis of nitrogenous compounds (g N/day) was

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calculated as a function of the absorbed purines, both using the equations reported by

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Chen and Gomes (1992).

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2.6. Statistical analysis

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Data from intake, digestibility, purine derivatives and microbial efficiency were

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analyzed using the MIXED procedure on SAS (version 9.3), based on a 4 × 4 Latin

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square design in a 2 × 2 factorial design, and the effects of the model were the type of

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silage (S), concentrate (C) and the S × C interaction (fixed effects), and animal and time

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(random effects). Data were submitted to the analysis of variance and t-test was used for

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comparisons of the means. A matrix of compound-symmetry covariance was used, 6

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which was selected based on the corrected Akaike information criterion (AICC).

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Homogeneity of variance among treatments was assumed, and degrees of freedom were

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estimated using the Kenward-Roger method (Kenward and Roger, 2009). All statistical

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procedures were performed using 0.05 as the critical probability level for type I error.

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3. Results and discussion

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3.1. Nutrient intake and digestibility

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There was S × C interaction (P < 0.05) on the intake of nutrients, except for the

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intake of NDF (Table 2). The addition of concentrate to the diets increased the intake of

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DM, OM, NFC and TDN (P < 0.05) for both corn and Stylosanthes silages. The diet

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containing SS with C had similar values of DM, OM and TDN intake (P > 0.05)

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compared to the diet with CS and C, whereas in diets without C, lower levels of nutrient

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intakes were observed for the SS diets compared to the CS diets (P < 0.05). The lower

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intake of DM, OM, NFC and TDN in the diet containing only SS compared to the CS

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diet is probably due to the filling effect caused by SS, which has a higher concentration

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of lignin and indigestible NDF (iNDF), as reported by Silva et al. (2012). The values of

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the DM intake for the diets with C (31.5 and 33.8 g/kg BW for CS and SS, respectively)

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observed in this study were similar to those observed by Moreno et al. (2010) in sheep

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fed diets with 40% C (31.3 g/kg kg BW). Cardoso et al. (2006) observed DM intake of

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3.19 kg/100 kg of BW in Île-de-France lambs fed diets containing approximately 40%

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C.

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The intake of CP in the diets without C was not different between the SS and CS

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(P > 0.05), but with the addition of C to the diets, the SS showed higher intake levels

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than CS (P <0.05). The diet with SS and C with diet had higher NFC intake compared to

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the diet with CS and C, but the opposite behavior was observed for the diets containing 7

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only silage. The similar CP intake between the diets without C and the higher intake for

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the diet with SS and C is because animals fed the SS diets selected more leaves, which

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have higher concentrations of CP, compared to the CS diet. The apparent digestibility of the nutrients was not affected by the interaction S ×

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C (P > 0.05), with an exception for the OM digestibility (P < 0.05; Table 3). There were

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effects of S and C (P < 0.05) on the digestibility of DM, EE and NFC (P < 0.05). The

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SS diets showed lower digestibility of these nutrients than the CS diets. In the diets

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containing only forage, the CS had a higher OM digestibility compared to the SS diet (P

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< 0.05). However, the OM digestibility did not differ between the SS and CS diets, both

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containing C (P > 0.05). Sheep fed the diet SS and C probably had a sorting behavior to

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achieve the same energy requirement, by selecting a diet with a higher energy content,

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despite the nutritional characteristics of the SS, like the high iNDF content and lower

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DM digestibility. Furthermore, the addition of concentrate to the SS diet minimized the

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effects of the lower DM intake of the diet containing only SS, resulting in OM

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digestibility to those of the CS diet with the concentrate. The similar CP intake between

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the diets without C and the higher intake for the diet with SS and C is because animals

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fed the SS diets selected more leaves, which have higher concentrations of CP

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compared to the CS diet. This sorting behavior was evidenced by the high proportion of

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stems in the orts of animals fed the SS diet.

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The lack of an effect on the digestibility of NDF for different silages can be

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explained by the increase in the ruminal retention time of the particles in the diets with

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higher forage proportion, as previously observed in other studies with sheep

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(Mupangwa et al., 2000; Silva et al., 2012).

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3.2. Ammonia concentration and ruminal pH The ruminal pH was affected by the S × C interaction and by the sampling time

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(P < 0.05, Table 4). Considering the diets without C, the pH of SS was higher than CS.

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However, in the diets with C, the pH values were similar for both SS and CS diets. The

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higher ruminal pH in the animals fed the SS diet without concentrate compared to those

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fed the CS diet (6.74 vs. 6.08) was probably due to the high concentrations of anionic

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salts and CP in the legumes, which increase the buffering capacity of these plants

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(Playne and McDonald, 1966; Heinritz et al., 2012). In addition, the higher starch

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content in CS decreases the pH because of the higher fermentation. Ladeira et al. (2002)

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observed an average ruminal pH of 7.0 in sheep fed Stylosanthes guianensis hay.

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The SS diet showed higher ruminal ammonia concentration than the CS diet

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(11.75 vs. 9 mg/dL). The higher ruminal ammonia concentration in the animals fed the

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SS diets (with or without concentrate) was most likely due to the higher nitrogen levels

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in the rumen resulting from the increased consumption of CP, as explained previously.

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The ruminal ammonia concentration observed in the present study was similar to that

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observed by Ladeira et al. (2002).

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3.3. Microbial protein synthesis

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The efficiency of microbial protein synthesis (EfMic) was affected by the S × C

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interaction (P < 0.05). In diets without C, the EfMic was higher for the SS than CS.

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However, the EfMic values were similar for both the SS and CS diets with concentrate.

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The addition of concentrate to the SS diet decreased the EfMic, whereas no changes

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were observed with the addition of C to the CS diet. The increase in microbial protein

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production when the concentrate was added to the diet is due to the increased

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availability of energy for the development of rumen microorganisms, resulting from the 9

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increased TDN intake. The lack of an effect based on the type of silage indicates that SS

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can replace CS without compromising the development of ruminal microorganisms. The

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increase in the EfMic in the SS diet can be explained by the decrease in TDN intake,

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because this parameter is a ratio between CPmic production and TDN intake.

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Furthermore, the animals fed the SS diet without concentrate had an increase in nitrogen

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recycling because of the low intake of DM and TDN.

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5. Conclusions

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Feeding exclusive Stylosanthes cv. Campo Grande silage results in lower intake

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and digestibility compared to corn silage. However, Stylosanthes silage has a high

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potential for sheep feeding in the diets containing 40% concentrate in the total DM,

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because it has similar effects on nutritional value and ruminal fermentation as corn

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silage. Thus, Stylosanthes silage is recommended for use in sheep diets.

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6. Acknowledgements

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The authors are grateful to CNPq (National Council for Science and Technology

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Development), INCT-CA (National Institute of Science and Technology - Animal

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Science) and FAPEMIG (The Minas Gerais state Research Foundation) for funding this

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project.

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7. References

212

AOAC, 1997. Official Methods of Analysis. Association of Officials Analytical

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Chemists, Vol. 1., 16th ed. Gaithersburg, Maryland, USA.

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Bamikole, M.A., Ezenwa, I., Akinsoyinu, A.O., Arigbede, M.O., Babayemi, O.J., 2001.

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Performance of West African dwarf goats fed Guinea grass-Verano stylo mixture,

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N-fertilized and unfertilized Guinea grass. Small Rum. Res. 39,145–152.

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Cardoso, A.R.; Pires, C.C.; Carvalho, S., Galvani, D.B., Jochims, F., Hastenpflug, M.,

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Wommer, T.P., 2006. Intake of nutrients and performance of lambs fed with diets

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containing different levels of neutral detergent fiber. Cienc. Rur. 36,215–221.

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Chaney, A.L., Marbach, E.P., 1962. Modified reagents for determination of urea and

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ammonia. Clin. Chem. 8, 130–132.

Chen, X.B., Gomez, M.J., 1992. Estimation of microbial protein supply to sheep and

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cattle based on urinary excretion of purine derivatives an overview of the

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technical details. International Feed Resource Unit, Rowett Research Institute.

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Occasional Publication, Aberdeen, pp. 2-20.

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Detmann, E., Valadares Filho, S.C., 2010. On the estimation of non-fibrous

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carbohydrates in feeds and diets. Arq. Bras. Med. Vet. Zootec. 62, 980–984.

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Foster, J.L., Adesogan, A.T., Carter, J.N., Blount, A.R., Myer, R.O., Phatak, S.C., 2009.

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Intake, digestibility, and nitrogen retention by sheep supplemented with warm-

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season legume hays or soybean meal. J. Anim. Sci. 87, 2891–2898.

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Heinritz, S.N., Martens, S.D., Avila, P., Hoedtke, S., 2012. The effect of inoculant and

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sucrose addition on the silage quality of tropical forage legumes with varying

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ensilability. Anim. Feed Sci. Technol. 174, 201–210.

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Hue, K.T., Van, D.T.T., Ledin, I., 2008. Effect of supplementing urea treated rice straw

235

and molasses with different forage species on the performance of lambs. Small

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Rum. Res. 78, 134–143.

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Kenward, M.G. and Roger, J.H., 2009. An improved approximation to the precision of

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fixed effects from restricted maximum likelihood. Comput. Stat. Data An. 53,

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2583–2595.

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Ladeira, M.M, Rodriguez, N.M., Borges, I. Gonçalves, L.C., Saliba, E.O.S., Miranda,

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L.F., 2002. Nitrogen balance, amino acid degradability and volatile fatty acid

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concentration in the rumen of sheep fed Stylosanthes guianensis hay Rev. Bras.

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Zootec. 31, 2350–2356.

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Licitra, G., Hernandez, T.M., Van Soest, P.J., 1996. Standardization of procedures for nitrogen fractionation of ruminant feeds. Anim. Feed Sci. Technol. 57, 347–358.

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Mertens, D.R., 2002. Gravimetric determination of amylase-treated neutral detergent

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fiber in feeds with refluxing in beaker or crucibles: collaborative study. J. AOAC

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Int. 85, 1217–1240.

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Moreno, G.M.B.; Sobrinho A.G.S.; Leão, A.G. Loureiro, C.M.B., Perez, H.L., Rossi,

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R.C., 2010. Performance, digestibility and nitrogen balance of lambs fed corn

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silage or sugar cane based diets with two levels of concentrate. Rev. Bras. Zootec.

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39, 853–860.

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Mupangwa, J., Ngongoni, N., Topps, J., Acamovic, T., Hamudikuwanda, H., Ndlovu,

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L., 2000. Dry matter intake, apparent digestibility and excretion of purine

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derivatives in sheep fed tropical legume hay. Small Rum. Res. 36, 261–268.

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NRC, 2007. Nutrient Requirements of Small Ruminants: Sheep, Goats, Cervids, and New World Camelids, 1st ed. National Academy Press, Washington, DC.

Playne, M.J., McDonald. P., 1966. The buffering constituents of herbage and of silage. J. Sci. Food Agric. 17, 264–68.

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Silva, L.D., Pereira, O.G., Ribeiro, K.G., Valadares Filho, S.C., Silva, T.C. 2012. Intake

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and total apparent digestibility of nutrients of corn and Stylosanthes silages in

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diets for sheep. In: Joint Annual Meeting ASAS ADSA, 2012, Phoenix. J. Anim.

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Sci. 90, 541–541. 12

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Souza, W.; Pereira, O.G.; Ribeiro, K.G.; Santos, S.A.; and Valadares Filho, S.C. 2014.

265

Intake, digestibility, nitrogen efficiency, and animal performance of growing and

266

finishing beef cattle fed warm-season legume (Stylosanthes capitata plus

267

Stylosanthes macrocephala) silage replacing corn silage. J. Anim. Sci. 92, 4099–

268

4107.

270

Van Soest, P. J., and J. B. Robertson. 1985. Analysis of forages and fibrous foods.

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Cornell University, Ithaca.

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Table 1

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Ingredient proportions and chemical composition of the experimental diets, expressed

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based on the dry matter (DM) Dietas a

b

StS

CSc

StS+C

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271 272

CS+Cd

597.10

CS

-

-

Urea / ASe

4.83

2.90

Corn grain

-

395.10

Soybean meal

-

4.90

-

-

989.25

593.55

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995.17

10.75

6.45

-

395.10

-

4.90

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SS

cr

Ingredient proportions, g/kg DM

Chemical composition , g/kg DM f

286.82

Organic matter

936.15

Crude protein Ether extract

238.04

478.36

958.16

951.51

958.23

100.76

106.47

101.67

97.95

13.77

13.72

26.26

21.26

587.27

383.85

469.36

313.38

256.43

478.13

370.37

546.09

333.18

202.38

220.76

134.95

Hemicellulose

143.16

107.89

207.79

146.86

Lignin

110.93

73.58

40.82

31.57

NFCh

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Cellulose

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NDFg

508.10

M

Dry matter, g/kg NM

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a

Stylosanthes cv. Campo Grande silage; bStylosanthes cv. Campo Grande silage plus

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concentrate; ccorn silage; dcorn silage plus concentrate; eurea and ammonium sulfate at a

277

9:1 ratio. fnatural matter; gneutral detergent fiber corrected for ash and protein; hnon-

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fibrous carbohydrates; iacid detergent fiber.

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Table 2

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Least square means for nutrient intake by sheep fed Stylosanthes cv. Campo Grande or

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corn silage with or without concentrate.

With

Means

Dry matter (g/d)

88.79

673.54Bb

1409.41Aa

1041.47

Corn

973.56Ab

1197.67Aa

1085.61

823.55

1303.54

Means

612.43Bb

1337.61Aa

Corn

910.30Ab

1144.19Aa

761.36

1240.90

Means

8.50

0.02

<0.01

0.01

27.75

0.79

0.52

0.08

55.96

<0.01 <0.01

<0.01

73.90

0.04

<0.01

975.02 1027.24

160.36Aa

129.29

Corn

104.17Aa

115.91Ba

110.04

d

138.14

e

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NDF (g/d)

350.5

464.8

407.68

Corn

424.9

367.4

396.14

Means

387.70

416.12

Ac ce p

Stylosanthes

NFCf (g/d)

Stylosanthes

191.04Bb

693.80Aa

442.42

Corn

392.86Ab

634.49Ba

513.67

Means

291.95

664.14

g

TDN (g/d)

Stylosanthes

395.87Bb

1025.45Aa

710.66

Corn

709.71Ab

930.13Aa

819.92

552.79

977.79

Means

0.01

0.01

98.22Ab 101.19

<0.01

<0.01

Stylosanthes Means

S × Cd

0.40

M

Crude protein (g/d)

0.50

Cc

86.72

Organic matter (g/d) Stylosanthes

Sb

an

Stylosanthes

P-value

cr

Without

SEMa

ip t

Concentrate

us

Silage

<0.01

283

Means followed by the same uppercase letter in the columns and lowercase letter in the

284

rows are not significantly different based on a t-test (P < 0.05). astandard error of the 15

Page 15 of 19

285

mean; bsilage effect; cconcentrate level effect; dsilage × concentrate level interaction

286

effect. eneutral detergent fiber corrected for ash and protein; fnon-fibrous carbohydrates;

287

g

total digestible nutrients.

288

Ac ce p

te

d

M

an

us

cr

ip t

289

16

Page 16 of 19

289

Table 3

290

Least square means for the apparent digestibility (AD) of nutrients for sheep fed

291

Stylosanthes cv. Campo Grande silage or corn silage with or without concentrate.

With

Mean

Dry matter (g/kg)

25.0

Stylosanthes

521.1

707.6

614.3B

Corn

636.4

748.3

692.4A

Means

578.7b

728.0a

23.9

Organic matter (g/ kg) 576.4Bb

755.9Aa

Corn

699.4Ab

786.8Aa

637.9

771.3

Means

Stylosanthes

689.8

692.6

691.2

Corn

610.5

703.8

657.1

Means

650.1

Cc

S×Cd

<0.01 <0.01

0.09

<0.01 <0.01 0.049

14.6

0.20

0.08

0.10

24.4

0.73

0.60

0.33

30.1

<0.01 <0.01

0.06

d

698.2

e

Corn

te

NDF (g/ kg)

631.5

607.5

Means

597.9

623.8

564.4

640.1

602.3 619.5

Ac ce p

Stylosanthes

Sb

7433.1

M

Crude protein (g/ kg)

666.1

an

Stylosanthes

P-value

cr

Without

SEMa

ip t

Concentrate

us

Silage

NFCf (g/ kg)

Stylosanthes

625.8

843.1

734.5B

Corn

812.6

902.5

857.5A

Means

719.2b

872.8a

292

Means followed by the same uppercase letter in the columns and lowercase letter in the

293

rows are not significantly different based on a t-test (P < 0.05). astandard error of the

294

mean; bsilage effect; cconcentrate level effect; dsilage × concentrate level interaction

17

Page 17 of 19

e

295

effect.

neutral detergent fiber corrected for ash and protein;

296

carbohydrates..

f

non-fibrous

Ac ce p

te

d

M

an

us

cr

ip t

297

18

Page 18 of 19

Table 4

298

Least square means for the pH, ruminal ammonia concentration, and the microbial

299

protein synthesis and synthesis efficiency in sheep fed of sheep fed Stylosanthes cv.

300

Campo Grande silage or corn silage with or without concentrate. Concentrate Silage

With

Mean

pH

0.06

6.74Aa

6.06Ab

6.39

Corn

6.08Ba

6.17Aa

6.12

Mean

6.41

6.11

10.21

13.29

Corn

10.04

7.97

Mean

10.12

10.63

M

Stylosanthes

0.67

0.02

0.69 0.06

0.67

6.01

0.25 0.04

0.26

5.92

0.18 0.13

0.04

9.00B

Stylosanthes

34.93

62.21

48.57

Corn

53.56

Mean

44.24b

d

58.00

te

62.32a

EfMice (g MP/ kg TDNf) Stylosanthes

89.66Aa

59.13Ab

74.39

Corn

60.74Ba

66.11Aa

63.42

Mean

75.20

62.18

Ac ce p

0.07 0.06

S×Cd

11.75A

Microbial protein synthesis (g/d) 62.43

Cc

0.049

an

Ruminal ammonia (mg/dL)

S

us

Stylosanthes

P-value

b

cr

Without

SEMa

ip t

297

301

Means followed by the same uppercase letter in the columns and lowercase letter in the

302

rows are not significantly different based on a t-test (P < 0.05). astandard error of the

303

mean; bsilage effect; cconcentrate level effect; dsilage × concentrate level interaction

304

effect; emicrobial protein synthesis efficiency; gtotal digestible nutrients.

19

Page 19 of 19