Digestibility Of Lambs Research Articles

Effect of Salvia sclarea L. extract on growth performance, antioxidant capacity, and immune function in lambs.

This study aimed to explore the effects of Salvia sclarea extract on the growth performance, apparent nutrient digestibility, antioxidant capacity, and immune function of the lambs. Sixty female lambs (Chinese Merino sheep) aged 2 months and weighing 20 ± 2 kg were selected and randomly divided into five groups of 12 lambs each. The control group (CK) received only basal feed, whereas the experimental group was supplemented with different concentrations of salvia sclarea extract in the basal feed at 0.04, 0.08, 0.12, and 0.16 mL/kg (CL1, CL2, CL3, and CL4, respectively). The feeding period was 85 days, including 15 days of pre-feeding and 70 days of regular feeding. Body weight and feed intake were recorded during the test period, and blood was collected at the end of the test to determine immune and antioxidant indices. The results showed that the average daily weight gain and feed intake of the lambs were significantly higher in the CL3 group than in the CK group (p < 0.05). In addition, the apparent nutrient digestibility of crude protein and neutral detergent fiber increased significantly (p < 0.05). The dry matter, acid detergent fiber, and ether extract were not significantly different (p > 0.05). Serum levels of superoxide dismutase, catalase, and glutathione peroxidase and antioxidant capacity were significantly higher in the CL2, CL3, and CL4 groups than in the CK group, whereas malondialdehyde levels were significantly lower (p < 0.05). The serum levels of immune globulin immune globulin A, immune globulin G, immune globulin M, interferon-γ, and interleukin-10 were significantly higher and the levels of tumor necrosis factor-α and interleukin-1β were significantly lower in the CL2, CL3, and CL4 groups (p < 0.05). In conclusion, the addition of the S. sclarea extract to the diet promoted growth performance and nutrient digestion in lambs. Immune response was improved by increasing Ig and cytokine concentrations. It enhances antioxidant status by increasing antioxidant enzyme activity in lambs.

Nutrient utilization and ingestive behavior by lambs fed a partial mixed ration consisting of different carbohydrate sources combined with fresh alfalfa

The objective of the current study was to evaluate the nutrient utilization by lambs fed partial mixed ration (PMR) containing either cereal grain or fibrous by-products as an energy source complemented with fresh alfalfa. Eighteen male Corriedale × Ile-de France lambs (32.2 ± 1.82 kg body weight and 4 months old) fitted with permanent rumen catheters were individually housed in metabolism cages and randomly assigned to the treatments (diets): FF, fresh alfalfa ad libitum; PMR-C, PMR containing cereal grains plus fresh alfalfa or PMR-F, PMR containing fibrous by-products plus fresh alfalfa. The amount of PMR offered corresponded to 75% of the potential total dry matter intake of lambs, in two equal meals daily (i.e. morning and afternoon) whereas fresh alfalfa was offered ad libitum from 10:00 to 18:00 h The inclusion of PMR, independently of the energy source, increased the nutrient intake and digestibility of lambs and reduced daily eating time. The ruminal fluid of lambs fed either PMR showed lower pH, higher propionate and butyrate concentration, and lower NH3 concentration compared to lambs fed only alfalfa (P < 0.01). Lambs fed PMR-F showed lower digestibility of N compounds and ruminal ammonia concentration compared to lambs fed PMR-C (P < 0.01). We concluded that offering PMR combined with fresh alfalfa to lambs had positive effects on nutrient intake, regardless of whether the energy source in PMR was starch or fibers.

Effect of Dietary Inclusion of Riboflavin on Growth, Nutrient Digestibility and Ruminal Fermentation in Hu Lambs

The study evaluated the influences of riboflavin (RF) supply on the growth performance, nutrient digestibility and ruminal fermentation in lambs. Forty-eight Hu lambs were randomly assigned into four groups receiving RF of 0, 15, 30 and 45 mg/kg dry mater (DM), respectively. Increasing RF supply did not affect the DM intake, but quadratically increased the average daily gain and linearly decreased feed conversion ratio. Total-tract DM, neutral detergent fibre, acid detergent fibre and crude protein digestibility increased quadratically. Rumen pH and propionate molar percentage decreased linearly, total volatile fatty acids concentration, acetate proportion and the ratio of acetate to propionate increased linearly, but ammonia nitrogen concentration was unchanged with increasing RF supply. Linear increases were observed on the activities of carboxymethyl-cellulase, xylanase, pectinase and protease, and the populations of bacteria, fungi, protozoa, dominant cellulolytic bacteria, Ruminobacter amylophilus and Prevotella ruminicola. Methanogens population was not affected by RF supplementation. The microbial protein amount and urinary total purine derivatives excretion increased quadratically. The results indicated that 30 mg/kg DM RF supply improved growth performance, rumen fermentation and nutrient digestion in lambs.

Effect of Caragana korshinskii Kom. as a partial substitution for sheep forage on intake, digestibility, growth, carcass features, and the rumen bacterial community

The aim of this study was to verify that Caragana korshinskii Kom. (CK) as a component of sheep forage influences lamb digestibility and rumen fermentation by altering the rumen microbial community. Hence, 12 female Tan sheep were allocated into 2 groups: receiving (CK group) or not (control group) 10% of the diet forage fraction with CK. During the 60-day experiment, growth performance, apparent digestibility, rumen volatile fatty acids (VFAs), and nitrogen balance were measured. Meanwhile, the rumen bacterial community diversity and composition were detected by the 16S rRNA sequence. The results indicated that the apparent digestibility of acid detergent fibre (ADF) tended to be higher (0.05 < P < 0.10), and the feed conversion efficiency was improved (P < 0.05) when CK was offered. Compared to those under alfalfa, the composition and abundance of the rumen microbial community were altered in the CK group, and the phylum Firmicutes, which is involved in promoting fibre digestion, increased in abundance. Moreover, VFAs tended to decrease (0.05 < P < 0.10), and the molar proportion of butyrate declined; similarly, levels of hypoxanthine and xanthine were lower (P < 0.05) in the sheep fed CK and may have been responsible for the decreased abundance of Fibrobacter spp., which are cellulolytic ruminal bacteria associated with VFA production.

Development of regression model of proteins attackability process in meat food (in vitro)

In the presented article the authors consider the issues of development of regression model for process of food digestion by proteolytic enzymes in human body. The authors use correlation analysis. They analyze the main nutritional values and physical and chemical properties of meat products, the modes of heat treatment of semi-finished lamb products. The essential parameters and features are determined to find the dependence between the factor values and efficient values of the basic raw material, which affect the quality of the technological processes and, in general, the finished product. The regression model equation is mathematically calculated by methods of solving K. Gauss linear equations. The standard deviations of parameters are calculated, the initial data are normalized; the matrices of the pair correlation coefficients, lower and upper limits of their values are compiled. Equations of the mathematical regression model of meat proteins attackability by proteolytic enzymes — in vitro (pepsin, trypsin) are developed. It is proved that the obtained equation represents a regression model of the process of meat food proteins attackability by enzymes (pepsin, trypsin and chymotrypsin), depending on the determined 3 essential factors (weight of a meat piece, duration of frying, collagen content in lamb meat). Also this equation reflects the process of lamb digestibility in a digestive tract of a human body.

Effects of single or combined supplementation of probiotics and prebiotics on ruminal fermentation, ruminal bacteria and total tract digestion in lambs

Probiotics (beneficial living microorganisms) and prebiotics (fiber, cell wall material, mannan polysaccharides derived through hydrolysis of yeast cell walls) are feed additives that may have beneficial extra-nutritional pharmaceutical and/or metabolic effects on livestock health and growth performance. Due to differences in modes of action, their combination may have additive effects on digestion and fermentation in ruminants. For this reason, four male lambs (Dorper; 45.1 ± 2.7 kg initial weight) with “T” cannulas in the rumen were used in a 4 × 4 Latin square experiment to evaluate the effects of single or combined supplementation of probiotics and prebiotics on ruminal fermentation and total tract digestion. Dietary treatments consisted of a cracked corn-based basal finishing diet supplemented with: 1) no eubiotics (Control); 2) 3 g of live saccharomyces cerevisiae /lamb/day (2 × 1010 cfu/g, SC), 3) 3 g of mannan oligosaccharide (30 % w/w) plus b-glucans (20 % w/w) /lamb/day (MOS), and 4) combination of 1.5 g/day SC and 1.5 g/day MOS (SCMOS). Compared to controls, SC supplementation tended (P = 0.09) to increase total tract digestion of DM and OM, and increased (P < 0.05) total tract digestion of N, starch, and digestible energy (DE). Compared with Control, MOS increased total tract NDF (7.9 %, P < 0.01) and starch digestion, and tended to improve total tract digestion of (P = 0.09), N (P = 0.07), and DE diet (P = 0.07). Compared to Control, SCMOS increased (P ≤ 0.03) total tract digestion of all fractions evaluated, including a 4.2 % (P < 0.01) increase in DE. Although lambs fed MOS had greater (6.7 %, P = 0.02) NDF digestion than those fed SC, differences in total tract digestion of DM, OM, N, starch and DE diet were not appreciable (P ≥ 0.24). Compared with SC and MOS fed separately, SCMOS increased (P < 0.05) total tract digestion of N and NDF. Supplemental MOS and SCMOS tended (P = 0.09) to promote greater ruminal pH than the Control. Combining supplementation decreased (P ≤ 0.03) the molar proportion of butyrate and ruminal ammonia, consistent with decreased of ruminal concentration of C. aminophilum. Probiotic/prebiotic supplementation of high-energy lamb finishing diets enhances total tract digestion and digestible energy. Reduction hyper-ammonia producing ruminal bacteria with the combination probiotic plus prebiotic may contribute to improved dietary N economy. The combination of probiotics with prebiotics potentiate positive effects on digestion and ruminal fermentation in lambs fed a high-energy diets.

The Dietary Supplemental Effect of Nitroethanol in Comparison with Monensin on Methane Emission, Growth Performance and Carcass Characteristics in Female Lambs.

Simple SummaryThe objective of present study was to determine the effects of 2-nitroethanol (NEOH) in comparison with monensin on methane (CH4) emission, growth performance and carcass characteristics in female lambs. Both monensin and NEOH are potent CH4 inhibitors that can reduce dietary energy loss. The average daily gain (ADG) and feed conversion rate were improved with monensin and NEOH addition, suggesting that NEOH in comparison with monensin presented a similarly lasting beneficial effect on feed efficiency for female lambs. In addition, monensin and NEOH increased the net muscle percentage to carcass weight (p = 0.03), and they caused a reduction in feed consumption and feed costs resulting in a higher net revenue and economic efficiency. In summary, NEOH in comparison with monensin presented a greater promoting effect on energy utilization in the female feedlotting lambs by inhibiting rumen methanogenesis more efficiently.This study was conducted to evaluate the dietary supplemental effects of 2-nitroethanol (NEOH) in comparison with monensin on methane (CH4) emission, growth performance and carcass characteristics in female lambs. Sixty female, small-tailed Chinese Han lambs (3.5 ± 0.3 month) were randomly allotted into three dietary treatment groups: (1) Control group, a basal control diet, (2) monensin group, the basal diet added with 40 mg/kg monensin, (3) NEOH group, the basal diet added with 277 mg/kg nitroethanol, and the feedlotting trial lasted for 70 days. Although dietary addition of monensin and NEOH did not affect nutrient digestibility of lambs, both monensin and NEOH decreased the calculated CH4 production (12.7% vs. 17.4% decrease; p < 0.01). In addition, the CH4 production represents less dietary energy loss in the monensin and NEOH group than in the control, indicating that monensin and NEOH are potent CH4 inhibitors that can reduce dietary energy loss. Dietary addition of monensin and NEOH decreased dry matter intake (p < 0.01); however, they increased the ADG of female lambs (p < 0.01). As a result, both monensin and NEOH increased feed conversion efficiency of the feedlotting lambs (p < 0.01), suggesting that feed energy saved from CH4 production promoted the feed efficiency and ADG in the present study. Except for the fact that NEOH addition increased the net muscle percentage to carcass weight (p = 0.03), neither monensin nor NEOH had a significant influence on carcass characteristics of female lambs (p > 0.05). From an economic point of view, NEOH and monensin caused a reduction in feed consumption costs, therefore resulting in a higher net revenue and economic efficiency than the control. In summary, dietary supplementation of NEOH in comparison with monensin presented a more promoting effect on energy utilization in female lambs by inhibiting rumen methanogenesis more efficiently, and NEOH improved the net revenue and economic efficiency more significantly than monensin.

Enhancing the Utilization of Palm Leaf Hay Using Bacillus subtilis and Phanerochaete chrysosporium in the Diet of Lambs Under Desert Conditions

Abstract The efficiency of the bacterium Bacillus subtilis and white-rot fungus Phanerochaete chrysosporium on growth performance, blood metabolites, carcass characteristics, meat composition and nutrient digestibility of lambs fed crushed whole palm leaf hay was investigated for 105 d. In Experiment 1 (Growth experiment), twenty-four lambs (29.5 ± 1.25 kg) were divided into four feed-based treatments: (1) concentrate and wheat straw ad libitum (control), (2) palm leaf hay (DPL), (3) palm leaf hay supplemented with 2 g of B. subtilis and P. chrysosporium (DPL2) or (4) palm leaf hay supplemented with 4 g of B. subtilis and P. chrysosporium (DPL4). In Experiment 2 (Digestibility experiment), twelve rams, three from each treatment, were used to study nutrient digestibility using the faecal bag technique. Results of the Experiment 1 showed that the DPL4 showed greater (P=0.049) live-weight gain than the control. The diets containing palm leaf hay showed lower (P=0.001) roughage and total feed intake and higher (P=0.001) feed efficiency than the control. Increased serum total protein, globulin, urea-N, aspartate aminotransferase and alanine aminotransferase (ALT) levels were observed with the DPL4 (P˂0.05). Additionally, diets containing palm leaf hay showed higher ALT levels than the control. The DPL4 increased the hot carcass weight (P=0.006) and dressing percentage (P=0.036), and the diets supplemented with B. subtilis and P. chrysosporium decreased (P˂0.05) the tail fat and all fat levels compared with the DPL treatment. Results of the Experiment 2 showed that nutrient digestibility was lower (P˂0.05) with the DPL and DPL2 than with the control and DPL4. Compared with the control, nutrient digestibility of DPL4 was not affected. It is concluded that replacement of wheat straw with palm leaf hay did not affect the feed utilization or animal performance of the lambs; however, supplementation with B. subtilis and P. chrysosporium at 4 g/lamb daily enhanced the growth performance, and carcass characteristics without any adverse effects on blood metabolites.

Growth performance, nutrient digestibility, immune responses and antioxidant status of lambs supplemented with humic acids and fermented wheat bran polysaccharides

This study was conducted to evaluate the effects of sodium humate (SH) and/or fermented wheat bran polysaccharides (FWBPs) on growth performance, nutrient digestibility, immune responses and antioxidant status of lambs. Seventy-two 4-month-old female crossbred (Dorper × Mongolian Sheep) lambs with initial body weight (BW) of 34.82 ± 1.07 kg were used. Lambs were allotted to a 2 × 2 factorial arrangement with 2 sodium humate (SH) supplemental levels (0 or 2.5 g of SH/kg of diet) and 2 FWBPs supplemental levels (0 or 3 g of FWBPs/kg of diet) according to their initial BW. There were 3 lambs per pen and 6 pen replicates per diet. Lambs were adapted to diets for 15 d, and the experiment was conducted for 60 d. Bodyweight and feed intake were recorded. Fecal samples were collected from each lamb during the last 10 d of the trial to determine nutrient digestibility. Blood was collected at the end of the trial, and used to assess blood metabolites, immune responses and antioxidant status. The results showed that supplemental SH did not affect growth performance of lambs. The ADG of lambs were increased (P < 0.05) by FWBPs supplementation, and DMI were tended to be higher (P = 0.056). There was no effect of SH supplementation on nutrient digestibility of lambs. Apparent digestibility of DM, OM and CP were increased by FWBPs supplementation (P < 0.05). Moreover, supplementation of FWBPs tended to increase (P = 0.092) apparent digestibility of NDF. Supplemental FWBPs increased (P < 0.05) IgG, IgM and IL-10 concentrations and CAT activity in plasma. However, the adverse effect of SH supplementation (P = 0.070) was found in plasma IgG concentration. In conclusion, FWBPs supplementation can promote growth performance and nutrient digestion, improve immune responses by increasing immunoglobulins and cytokine concentrations, enhance antioxidant status by increasing antioxidant enzyme activities in lambs. On the other hand, there were no benefits from the SH supplementation on the growth performance, nutrient digestibility, immune function and antioxidant status of lambs.

Trace mineral metabolism and nutrient digestibility in lambs supplemented with zinc sulfate during an adrenocorticotropic hormone challenge

The objective was to evaluate the effects of Zn supplementation and adrenocorticotropic hormone (ACTH) injections on nutrient digestibility, trace mineral metabolism and status. It was hypothesized that ACTH would decrease nutrient digestibility and Zn retention, but Zn supplementation would improve Zn retention, regardless of ACTH administration. Twenty-two Polypay cross weathers previously enrolled in a trial, consumed a moderately Zn deplete diet (22 mg Zn/kg DM) for 52 d, followed by being housed in metabolism crates for 15 d while receiving one of two diets: CON (Zn deplete diet) or ZINC (CON plus 40 mg Zn/d from ZnSO4). Lambs rested for one day outside of crates then returned to crates for this 5 d study. Lambs continued to receive dietary Zn treatments and were randomly assigned to receive injectable treatments, once daily on d 1–4 at feeding: SALINE (2 mL saline I.M.), STRESS (80 I.U. ACTH I.M.); lamb was experimental unit (n = 5–6/treatment) in a 2 × 2 factorial design. Total fecal and urine collection was conducted on d 3–5, and blood samples were collected on d 0, 1, and 4, 3 h post feeding. Day 4 plasma Zn concentrations, covariate adjusted with d 0 concentrations, displayed a diet × injection tendency (P = 0.06) where ACTH given to ZINC lambs depressed plasma Zn to values similar to CON lambs. Day 1 and 4 cortisol concentrations determined 3 h after injection administration were increased in STRESS vs. SALINE (P < 0.01). Day 4 plasma Cu concentrations, covariate adjusted with d 0 concentrations were lesser in STRESS vs. SALINE (P = 0.04). Day 4 plasma Fe concentrations were unaffected by diet or injection treatment (P ≥ 0.18). Apparent absorption of Zn was increased (P < 0.01) in CON vs. ZINC, but were similar in STRESS vs. SALINE (P = 0.13). Zinc retention, and apparent absorption of Mn and Cu was similar across treatments (P ≥ 0.19). Organic matter (OM) digestibility tended to be decreased in ZINC vs. SALINE (P = 0.07); neutral detergent fiber (NDF) and acid detergent fiber (ADF) digestibility were decreased (P ≤ 0.04) in ZINC vs. SALINE. Injection treatment had no effect on macronutrient digestibility (P ≥ 0.37). The CON lambs were marginally Zn deficient based on plasma Zn concentrations and rate of apparent absorption, while fiber digestion was impaired by Zn supplementation. Plasma cortisol concentrations indicate lambs receiving ACTH experienced physiological stress, however this had limited effects on macro or micronutrient metabolism.

Effects of different sources and levels of tannins on live performance and antioxidant response of Ossimi lambs

AbstractPomegranate peels (PP) and mango leaves (ML) were analysed for nutrients and tannin contents. In an in vitro test, ten diets were prepared; six contained 2, 4 and 6% of PP or ML, three diets supplemented with mixed levels of PP and ML (1 + 1%, 2 + 2% and 3 + 3%) and control diet free of them. Gas was measured after 3, 6, 12, 24, 48 and 72 h of incubation. Methane and rumen parameters were estimated. In an in vivo experiment, 40 Ossimi lambs were divided into four groups; the first was control, other groups (T1, T2 and T3) fed diets containing 6% PP, 6% ML or mix levels (3% PP + 3%ML), respectively, for 2 months. Results showed that PP and ML were rich in tannins. In the in vitro test, a maximum reduction in gas, methane and NH3-N was in 6% PP, 6% ML and mixed levels (3% PP + 3% ML). In the in vivo experiment, there were no differences in growth and digestibility of DM and nutrients between treatment groups. Only a lowered DM intake and protein digestibility in lambs fed 6% PP. Gas and methane emission was decreased significantly in lambs fed 6% PP, compared to other groups. TVFAs and NH3-N were decreased for treatment groups. Also, all treatments did not show any pathological changes in liver function or on oxidative stress markers. In conclusion, PP and ML can be used in sheep diets at inclusion levels of 6% and mixture without detrimental effects on general health of Ossimi lambs.

Trichostrongylus colubriformis infection in Santa Inês lambs: impact on feed digestibility, blood markers, and nitrogen balance.

This study aimed to evaluate the effects of Trichostrongylus colubriformis infection on the hemato-biochemical parameters, feed digestibility, and nitrogen balance in Santa Inês lambs. Eighteen three-month-old Santa Ines castrated male lambs (16.9 ± 1.43 kg of body weight) were randomly distributed in two experimental treatments: infected with T. colubriformis (I, n = 9) and uninfected (U, n = 9). The I group received a total of 45,000 L3 larvae of T. colubriformis (5,000 infective larvae, three times per week, for three weeks). During the experimental period, blood, feed digestibility, and nitrogen balance were evaluated. The I lambs showed a reduction in erythrocytes, hemoglobin, hematocrit, mean corpuscular volume, and total proteins, as well as an increase in platelets and eosinophils compared to those in the U group (p < 0.05). With the exception of total protein content, these values were within the normal range for the species. Furthermore, lower dry matter and organic matter digestibility were observed in the I lambs (p = 0.08). The present findings highlight that T. colubriformis infection has the potential to impair some hemato-biochemical parameters as well as feed digestibility in lambs, which could affect their productivity.

PSX-11 Effects of lamb’s breed and energy concentration of diet on nutrient digestibility and growth performance

Abstract The accumulation of subcutaneous adipose deposits occurs in many genotypes of animals adapted to tropical arid conditions. In sheep, good adaptation of fat-tailed sheep breeds, as Rabo Largo, to arid environmental conditions and food shortages can also undergo digestive and metabolic adaptation, including a greater capacity for digestion of poor roughage. Forty lambs (18±3 kg initial BW) were assigned in a randomized completely block design with a 2x2 factorial arrangement of treatments, with 2 breeds – B (Santa Inês- SI and Rabo Largo-RL) and 2 diets – D (low and high energy), resulting in four treatments: SILE, SIHE, RLLE and RLHE. Lambs (20 SI and 20 RL) were individually penned during 43 d and fed 1 of 2 diets with different concentrate: roughage ratio: low energy-LE (with 70% hay and 10.7% CP, DM basis) and high energy-HE (70% concentrate and 12.7% CP, DM basis). At the end of performance period, the intake was recorded and total feces collected for 5 d. Data were analyzed by ANOVA and when a significant effect (P &amp;lt; 0.05) was found, means were compared using Tukey’s method. The G:F ratio had effect only for D (0.12, 0.22, 0.10 and 0.24 for SILE, SIHE, RLLE and RLHE, respectively). There was observed an effect of D and B (P &amp;lt; 0.05) for all variables related to growth and digestibility, with higher means for SI and HE, except for NDF intake (495, 322, 340 and 268 g/d for SILE, SIHE, RLLE and RLHE, respectively) and NDF digestibility (63, 58, 59 and 45% for SILE, SIHE, RLLE and RLHE). It was observed an interaction D x B on CP intake, NDF intake and NDF digestibility. Breed and diets affected the performance and digestibility of lambs. However, RLLE increased the NDF digestibility, but decreased the ADG, suggesting higher fat depots accumulation.

PSXII-31 Severity of hay processing on dry matter intake, sorting behaviour, and apparent total tract digestibility in lambs

Abstract The objective was to evaluate digestibility and sorting behaviour of grass hay processed to differing severities. Thirty-six wether lambs were used in a completely randomized design and fed diets consisting of grass hay (82.2 %), whole barley (15.7 %), and a mineral-vitamin supplement (2.1 %). Treatments included: unprocessed hay (CON); shredded hay (SHRED); chopped hay (CHOP); and ground hay (GRIND). Lambs were fed their respective diet for 20 d followed by 4 d for measurement of feed intake and fecal output. Lambs fed CON (1.23 kg and 3.24 %) had greater DMI (P = 0.04 and 0.05) compared to CHOP (1.04 kg and 2.71 % BW), with SHRED (1.17 kg and 3.11 % BW) and GRIND (1.13 kg and 2.97 % BW) being intermediate. Undigestible NDF intake tended to decrease as processing severity increased (P = 0.05). Dry matter digestibility (67.6, 66.2, 59.6, and 60.8 % for CON, SHRED, CHOP, and GRIND, respectively; P &amp;lt; 0.01) generally decreased as the severity of forage processing increased. Crude protein digestibility was greatest in CON (68.6 %) compared to SHRED (60.83 %), CHOP (58.7 %), and GRIND (58.5 %; P &amp;lt; 0.01). ADF and aNDFom digestibilities were greater for CON (57.4 and 67.2 %) and SHRED (60.0 and 67.9 %) compared to CHOP (44.8 and 54.6 %) and GRIND (48.3 and 58.5 %; P &amp;lt; 0.001). CON and SHRED lambs sorted for larger particle sizes (particles &amp;gt; 19 mm and 8 to 19 mm; P &amp;lt; 0.001 and 0.025, respectively) while CHOP and GRIND lambs sorted for smaller particles (particles 4 to 8 mm and particles &amp;lt; 4 mm; P &amp;lt; 0.001 and 0.003, respectively). These results indicate that processing of grass hay does not increase nutrient digestibility partly because of the sorting behaviour of lambs.

Methane emissions, feed intake, and total tract digestibility in lambs fed diets differing in fat content and fibre digestibility

This study determined enteric methane (CH4) emissions, intake, and apparent total tract digestibility of diets varying in fibre digestibility and fat content. A Latin square design with two levels of fat [2.0% and 6.0% dry matter (DM); low and high] and two levels of fibre digestibility [low fibre digestibility (LFbD) or high fibre digestibility (HFbD)] was used. Higher dry matter intake (DMI) was observed (P &lt; 0.01) for LFbD versus HFbD diets (2.56 vs. 2.14 kg d−1, respectively), with no effect of fat. Fibre, DM, and organic matter digestibility were higher (P &lt; 0.01) for HFbD than LFbD diets. Increasing fat did not affect intake or digestibility of DM or dietary constituents but there was a fibre digestibility × fat content interaction (P &lt; 0.01) for fat digestibility. There was also a fat content × fibre digestibility interaction (P &lt; 0.05) for CH4 (g kg−1 DMI, organic matter intake, neutral detergent fibre intake, and percent gross energy intake), with emissions being higher when fat was added to the HFbD than the LFbD diet. The CH4 emissions per kilogram of neutral detergent fibre (NDF) digested were higher (P &lt; 0.01) for the HFbD than the LFbD diet. Methane emissions were increased by the HFbD diet, but inclusion of fat had a differential impact on CH4 emissions as a proportion of DMI or NDF intake in diets differing in fibre digestibility.

Dietary Supplementation of Lysophospholipids Affects Feed Digestion in Lambs.

Five experiments were conducted to examine effects of lysophospholipids (LPL) on live weight gain, nutrient digestibility, ruminal fermentation parameters, serum biochemical parameters and rumen bacterial community profile in fattening lambs. Two dietary treatments (pelleted complete feed supplemented without (control diet; CON) or with 0.05% LPL on dry matter basis) were tested in these experiments. Feed and water were provided ad libitum to lambs. The results showed that average daily gain (ADG) tended to increase or was not affected by LPL supplementation. Compared with CON, the supplementation of LPL resulted in an increase in dry matter, crude protein and organic matter digestibilities, and a decrease in neutral detergent fiber and acid detergent fiber digestibilities. Ruminal pH values did not change with LPL supplementation, but the concentrations of ammonia and total short chain fatty acids (SCFAs) were increased. The molar proportion of major individual SCFAs and the ratio of acetate to propionate were not affected by LPL supplementation. While the activity of lipase was decreased with LPL supplementation, all other serum biochemical parameters did not change. Rumen bacterial community was altered by LPL supplementation with the relative abundance of fibrolytic bacteria in the total bacterial population, such as Prevotella, decreased. In conclusion, LPL supplementation can alter feed digestion, but may not result in consistent positive responses in animal growth performance.

Tannin-containing legumes and forage diversity influence foraging behavior, diet digestibility, and nitrogen excretion by lambs1,2.

Diverse combinations of forages with different nutrient profiles and plant secondary compounds may improve intake and nutrient utilization by ruminants. We tested the influence of diverse dietary combinations of tannin- (sainfoin-Onobrichis viciifolia; birdsfoot trefoil-Lotus corniculatus) and non-tannin- (alfalfa-Medicago sativa L.) containing legumes on intake and diet digestibility in lambs. Freshly cut birdsfoot trefoil, alfalfa, and sainfoin were offered in ad libitum amounts to 42 lambs in individual pens assigned to 7 treatments (6 animals/treatment): 1) single forage species (sainfoin [SF], birdsfoot trefoil [BFT], and alfalfa [ALF]), 2) all possible 2-way choices of the 3 forage species (alfalfa-sainfoin [ALF-SF], alfalfa-birdsfoot trefoil [ALF-BFT], and sainfoin-birdsfoot trefoil [SF-BFT]), or 3) a choice of all 3 forages (alfalfa-sainfoin-birdsfoot trefoil [ALF-SF-BFT]). Dry matter intake (DMI) was greater in ALF than in BFT (P = 0.002), and DMI in SF tended to be greater than in BFT (P = 0.053). However, when alfalfa was offered in a choice with either of the tannin-containing legumes (ALF-SF; ALF-BFT), DMI did not differ from ALF, whereas DMI in SF-BFT did not differ from SF (P > 0.10). When lambs were allowed to choose between 2 or 3 legume species, DMI was greater (36.6 vs. 33.2 g/kg BW; P = 0.038) or tended to be greater (37.4 vs. 33.2 g/kg BW; P = 0.067) than when lambs were fed single species, respectively. Intake did not differ between 2- or 3-way choice treatments (P = 0.723). Lambs preferred alfalfa over the tannin-containing legumes in a 70:30 ratio for 2-way choices, and alfalfa > sainfoin > birdsfoot trefoil in a 53:33:14 ratio for the 3-way choice. In vivo digestibility (DMD) was SF > BFT (72.0% vs. 67.7%; P = 0.012) and DMD in BFT tended to be greater than in ALF (64.6%; P = 0.061). Nevertheless, when alfalfa was offered in a choice with either sainfoin or birdsfoot trefoil (ALF-SF; ALF-BFT), DMD was greater than ALF (P < 0.001 and P = 0.007, respectively), suggesting positive associative effects. The SF treatment had lower blood urea nitrogen and greater fecal N/N intake ratios than the ALF, BFT, or ALF-BFT treatments (P < 0.05), implying a shift in the site of N excretion from urine to feces. In conclusion, offering diverse combinations of legumes to sheep enhanced intake and diet digestibility relative to feeding single species, while allowing for the incorporation of beneficial bioactive compounds like condensed tannins into the diet.

Performance, feeding behavior and digestibility of nutrients in lambs with divergent efficiency traits

The aim was to evaluate the performance, feeding behavior and nutrient digestibility of lambs ranked according to residual feed intake (RFI) and residual intake and gain (RIG). A total of 102 male lambs (½ Dorper ½ Santa Inês; 70 d; 24.6 ± 3.71 kg) were used. The mean values of the RFI classes were -0.101, 0.0, and 0.091, and those of the RIG classes were 1.980, -0.032 and -2.369, for efficient, medium and inefficient lambs, respectively. Average daily gain was not correlated to RFI, but was correlated to RIG. Physiological parameters (i.e., respiratory frequency and heart rate), ruminal movement and rectal temperature were similar between efficient and inefficient lambs (i.e., for RFI and RIG; P > 0.05). Efficient RFI and RIG lambs spent less time ruminating and drinking water and more time eating (P < 0.05). Rumination time is a good feeding behavior marker to distinguish efficient and inefficient lambs (i.e., RFI and RIG). Inefficient feedlot lambs exhibited greater dry matter intake; this difference was not reflected in digestibility traits. These results may assist in the identification of more efficient animals to lower production costs and mitigate the environmental impact of lamb production systems.

127 Effects of Reed Sedge Peat on stress and digestibility of lambs at weaning

Abstract Fourteen lambs (age = 71.5 ± 4.15 d; BW = 24.1 ± 3.82 kg) were used to test the effects of feeding Reed Sedge Peat (RSP) during weaning. Lambs (10 females, 4 males) were randomly assigned by sex to one of two groups, they were either fed 56.8 g/d of RSP, or were not fed RSP. Both groups were fed 0.5% BW 18% show lamb grower complete feed (Ware Milling, Houston, MS) and had ad lib access to pasture [80% bermudagrass (Cynadon dactylon) and 20% dallisgrass (Paspallum dilatatum) during the day during the weaning portion of the study (14 d prior to weaning through 14 d after weaning). On d 15 after weaning, 10 of the lambs (6 females, 2 males) were randomly selected by treatment and moved to small individual pens where they underwent a digestibility trial for 8 days (3 d adjustment and 5 d collection) during which they were fed 1% BW hay/d and 4% BW/d 18% show lamb grower complete feed used during the weaning trail. At d 2 an initial blood sample was taken via jugular venipuncture, then ACTH was injected into the vein. Blood samples were taken at 15 min intervals for 1 h following synthetic ACTH injection, and analysed by conducting a cbc with differential. Reed-Sedge Peat had no effect (P &gt; 0.05) on digestibility of DM, OM, ash, protein, NDF, ADF, HC, or fat. Reed-Sedge Peat, also had no effect on intake DM (P = 0.3184), DMI per BW (P = 0.1062), hay intake (P = 0.9581), hay intake per BW (P = 0.9330), or concentrate intake (P = 0.8744). There was a tendency (P = 0.0552) for increased intake for RSP with regard to the concentrate. No difference for blood parameters between groups (P &gt; 0.05).

Effects of exogenous amylolytic enzymes on fermentation, nutritive value, and in vivo digestibility of rehydrated corn silage

This study aimed to evaluate the effects of amylolytic enzymes incorporation - into rehydrated ground corn on silage fermentative profile, chemical composition, microbiological profile, as well as their effects on feed intake and total tract apparent digestibility in lambs. Twenty-four silos of rehydrated ground corn with theoretical particle size of 2.5 mm and 625 g/kg DM content were used in a completely randomized design containing the following treatments: 1) Control (CON), without exogenous enzymes; 2) Glucoamylase (GLU), incorporation of 300 μL of glucoamylase product (Kerazyme 4560–300 U/mL, Kera Nutrição Animal, Bento Gonçalves, RS) per kg of ground corn (as-fed basis); and 3) alpha-amylase (AMY), incorporation of 300 μL of alpha-amylase product (Kerazyme 4577–300 U/mL, Kera Nutrição Animal) per kg of ground corn (as-fed basis). Nine castrated lambs (25.4 ± 4.57 kg body weight and 6.0 ± 0.4 months age) were enrolled to a 3 × 3 Latin square design to evaluate effects of silages with amylolytic enzymes on nutrient intake and total apparent digestibility. Enzyme products (GLU or AMY) increased (P ≤ 0.043) fermentative losses and decreased (P = 0.002) DM recovery of rehydrated corn. Silage treated with GLU tended to show greater (P ≤ 0.052) fermentative losses than those treated with AMY. Enzyme products increased (P < 0.001) DM content without (P ≥ 0.135) having major effects on chemical composition of rehydrated corn. On the other hand, enzyme products increased (P = 0.003) 48 h in vitro DM degradation and amylase activity, especially in silage treated with GLU. Regarding the enzyme treatments, GLU increased (P < 0.004) amylase activity, counts of lactic acid and aerobic bacteria, NH3-N and lactate concentrations while decreasing (P = 0.019) acetate concentration. Enzyme products decreased (P ≤ 0.034) pH and ethanol concentration and increased (P = 0.027) concentrations of butyric and lactic acids. Lambs fed rehydrated corn treated with enzyme products had greater (P ≤ 0.050) DM, CP, and starch intake and digestibility in relation to those fed CON. In addition, feeding AMY silage increased (P = 0.035) DM intake without affecting (P ≥ 0.713) nutrient digestibility in relation to GLU. In conclusion, there is evidence that enzyme products promote fermentation in rehydrated corn, which can further improve feed intake and nutrient digestibility in lambs. In addition, GLU treatment has a greater impact on silage fermentative losses but lambs fed GLU has lower DM intake than those fed AMY.