Performance Of Lambs Research Articles

Effects of Tannic Acid Supplementation on Growth Performance, Nutrients Digestibility, and Blood Metabolite in Lohi Male Lambs

The objective of the current study was to assess the effects of tannic acid supplementation on growth performance, nutrients digestibility, and blood urea nitrogen in the Lohi male lambs. Fifteen animals with an average age of 9-10 months and live body weight of 26.4 ± 0.52 kg were selected randomly. Three total mixed rations (TA0, TA4, TA8) having tannic acid 0, 4 g and 8 g/animal/day, respectively were given to the lambs (n = 5/treatment) for a period of 60 days under a Completely Randomized Design. Data regarding dry matter intake, body weight gain, nutrients digestibility, feed efficiency and blood urea nitrogen were collected. No significant difference (p > 0.05) was observed among the treatments in dry matter intake, body weight gain, apparent digestibility of nutrients, and feed efficiency. The blood urea nitrogen levels were significantly lower (17.0 mg/dL) in the TA8 treatment group compared to the TA0 group (22.1 mg/dL; SE = 1.3), indicating the protein bypass characteristic of tannic acid. It was concluded that supplementation of tannin may not have appreciable effects on growth performance and digestibility of the nutrients in lambs, but bypass value of protein was increased.

Effect of nonstructural carbohydrates on production performance, rumen metabolism and rumen health in lambs fed with isocaloric and isonitrogenous complete diets.

Nonstructural carbohydrates (NSC) are readily fermentable in the rumen and, are a critical factor while preparing protracted feed for higher animal performance. Four isocaloric and isonitrogenous complete feeds were prepared for this investigation to contain varying levels of nonstructural carbohydrates viz., 40.13 (NSC1), 45.21 (NSC2), 50.00 (NSC3) and 55.85 (NSC4) per cent, respectively. The four isocaloric and isonitrogenous complete feeds were tested in 32 Mecheri ram lambs (around three months of age) in a completely randomised block design (n = 8), and the lambs were fed their respective feed for six months. The study revealed that the increased NSC level in the complete diet increased the body weight and weight gain linearly (P < 0.05). The dietary NSC level affected the dry matter consumption in a quadratic manner (P < 0.05) and the lambs of the NSC4 group consumed significantly (P < 0.05) less DM compared to other dietary groups. The overall average feed conversion efficiency differed significantly (P < 0.05) among dietary groups. The correlation between dietary NSC level and faecal score was quadratic (r2 = 62.7, P < 0.05). The rumen pH, total nitrogen and NH3-N concentration were linearly decreased (P < 0.05) and the molar proportion of total short-chain fatty acids and propionic acid were increased (P < 0.05). The energy loss expressed as methane production was significantly (P < 0.01) lower for the high NSC diet-fed lambs. The lambs fed on a low NSC diet had significantly (P < 0.05) lower carcass weights, dressing percentage and loin eye area. The per cent share of rumen weight in the total fore stomach and the rumen papillae measurements length, width and surface area were significantly (P < 0.05) higher in high NSC diet-fed lambs. Increased levels of NSC in the diet increased (P < 0.05) fat deposition in the internal organs. The saturated fatty acids content in the meat was significantly (P < 0.05) lowered, whereas, the oleic acid and linoleic acid were increased (P < 0.05) as the NSC level increased in the diet. The study revealed that as the level of NSC increased in the complete diet there was a concomitant improvement in the final body weight, ADG and feed efficiency of post-weaned Mecheri lambs. It can therefore be recommended that the complete feed with 50 per cent NSC levels would be optimum to reap maximum returns from fattening Mecheri lambs.

Effect of coconut processing by-product graded feeding on carcass traits and meat quality of lambs

The inclusion of by-product coconut mesocarp skins (CMS) in diets was evaluated in feedlot lambs. The objective of this study was to evaluate CMS levels effects on carcass traits and meat quality of lambs. Thirty-five male lambs with an initial body weight of 16.9 ± 2.93 kg were distributed in a completely randomized design with five CMS levels in total dry matter (0; 4.8; 9.6; 14.4 and 19.2%) and fed during 71 d until slaughter. High levels of CMS decreased the intake of dry matter and negatively affected the performance of lambs. Fat and protein contents of Longissimus lumborum muscle (P < 0.05) and the saturated fatty acid (FA) decreased (P < 0.001) whereas polyunsaturated FA increased (P < 0.01) with the inclusion of CMS. The ratio t10/t11–18:1 increased with the inclusion of CMS (P < 0.001). The instrumental color descriptors were unaffected by CMS levels. According to the effects on the investigated meat quality traits we recommend up to 4.8% CMS in diets of confined lambs.

Alfalfa supplementation timing changes the rumen archaeal and fungal community composition and colonization in pre-weaning lambs.

The establishment of the rumen microbiota plays an important role in the rumen development. However, little is known about the effects of alfalfa supplementation time on rumen microbiota establishment. Here, a total of 42 Hu lambs, seven-day-old, were chosen for the study. After a week of adjustment, six lambs were sacrificed to establish a baseline. The remaining 36 lambs were randomly split into two groups: one receiving alfalfa hay at 14 days (EAF), the other at 42 days (LAF), both groups received milk replacer and starter pellets. Introducing alfalfa at 14 days of age significantly improved total dry matter intake between 28 and 42 days (p = 0.04) and average daily gain from both 14 to 28 days (p = 0.04) and 28 to 42 days (p < 0.01), but this effect disappears from 56 to 70 days (p > 0.05). At 42 days, the abundances of Naganishia, Ascochyta, and Neosetophoma in the EAF group were significantly higher (p < 0.05) than those in the LAF group (17.8% vs. 3.97, 10.89% vs. 1.77, and 1.27% vs. 0.09%, respectively). At 56 days, the abundances of Ascochyta, Wallemia, and Aspergillus in the EAF group were significantly lower (p < 0.05) than in the LAF group (3.53% vs. 16.40, 8.78% vs. 18.89, and 2.14% vs. 4.69%). At 70 days, Aspergillus abundance in the EAF group was significantly higher (p < 0.05) than in the LAF group (2.69% vs. 0.85%). The LEfSe analysis showed that Methanobrevibacter_smithii was the archaeal biomarker at 14 days in both groups. Methanobrevibacter_sp_AbM4 was enriched at 56 days in the LAF group. Compared to the LAF group, the specific fungal biomarkers in the EAF group included Sporobolomyces and Bullera at 14 days, Naganishia, Didymella, Cleistothelebolus, and Alloleptosphaeria at 42 days, Ascochyta, Neoascochyta, and Alfaria at 70 days. Correlation analysis results showed strong patterns of association both within and between archaea and fungi, which were influenced by alfalfa supplementation time. In summary, alfalfa supplementation at 14 days of age promotes the growth performance of lambs before weaning, and alfalfa supplementation timing significantly affects rumen archaeal and fungal communities and dynamical changes.

Effects of refused melon fruit in Canarana grass ensilage on intake, digestibility, serum biochemistry, performance, carcass characteristics and meat attributes of feedlot lambs.

Ensilage of refused fruit with forage is a viable approach to increase resource use in ruminant feed. The objective of this study was to investigate the impact of ensiling refused melon fruit (RMF) with Canarana grass on the intake, apparent digestibility, serum biochemistry, performance, carcass traits, and meat attributes of feedlot lambs. Four distinct silage treatment types were prepared by ensiling RMF at 0g/kg (control), 70g/kg, 140g/kg, and 210g/kg (as fed) with Canarana grass. Twenty-eight male Santa Inês lambs (7 lambs per treatment), initially weighing 22.3 ± 1.0kg at 120 days of age, were distributed in a completely randomized design and confined for a total of 96 days, including a 23-day adaptation period and 73 experimental days in a feedlot. The lambs received the treatment-silage in diets as a complete mixture with a roughage: concentrate ratio of 30:70. The inclusion of RMF in Canarana grass ensilage decreased (P < 0.05) the lambs' intake of dry matter, crude protein and metabolisable energy. The inclusion of RMF in ensilage had a quadratic effect (P < 0.05) on the digestibility of non-fibrous carbohydrates. The serum total protein and cholesterol levels decreased (P < 0.05) with the inclusion of RMF in the ensilage, but we observed no effect on the final weight and average daily gain of the lambs. The feed efficiency increased (P < 0.05) by including RMF in the Canarana grass ensilage. The RMF in the ensilage did not influence cold carcass weight and yield. The fat content of the meat decreased (P < 0.05) with the inclusion of RMF in the ensilage. It is recommended the inclusion of up to 210g/kg of RMF in Canarana grass ensilage to increase feed efficiency and avoid impacts on the performance and carcass attributes of confined lambs.

Supplementation of Acacia dealbata versus Acacia mearnsii leaf-meal has potential to maintain growth performance of lambs grazing low-quality communal rangelands in South Africa

Supplementing livestock grazing communal rangelands with leaf-meals from Acacia trees, which are currently considered as problematic invasive alien plants globally, may be a sustainable way of exploiting their desirable nutritional and anthelmintic properties. The current study evaluated worm burdens and growth performance of lambs grazing low-quality communal rangelands supplemented with leaf-meals prepared from the invasive alien plant species; Acacia mearnsii or A. dealbata. Forty, three-month-old ewe lambs weighing an average of 18.9 ± 0.60 kg were randomly allocated to four supplementary diets: (1) rangeland hay only (control), (2) commercial protein supplement plus rangeland hay, (3) A. mearnsii leaf-meal plus rangeland hay and (4) A. dealbata leaf-meal plus rangeland hay. All the supplementary diets were formulated to meet the lambs’ minimum maintenance requirements for protein. All the lambs were grazed on communal rangelands daily from 0800 to 1400 after which they were penned to allow them access to their respective supplementary diets until 08:00 the following morning. The respective supplementary diets were offered at the rate of 400 g ewe− 1 day− 1 for 60 days. Lambs fed the commercial protein supplement had the highest dry matter intake followed by those fed the Acacia leaf-meals and the control diet, respectively (P ≤ 0.05). Relative to the other supplementary diets, lambs fed the commercial protein supplement and A. dealbata leaf-meal had higher (P ≤ 0.05) final body weight and average daily gains. Dietary supplementation did not affect lamb faecal worm egg counts over the study period (P > 0.05). There was no association between supplementary diets and lamb FAMACHA© scores (P > 0.05). It was concluded that supplementation of Acacia dealbata versus Acacia mearnsii has the potential to emulate commercial protein in maintaining growth performance of lambs grazing communal rangelands in the dry season.

Effects of Alhagi camelorum Fisch polysaccharide from different regions on growth performance and gastrointestinal microbiota of sheep lambs.

Polysaccharides derived from Alhagi camelorum Fisch possess diverse activities, making them a potential prebiotic candidates for enhancing lamb health. This study investigated the immunomodulatory effects of Alhagi camelorum Fisch polysaccharides from Aksu (AK) and Shanshan (SS) regions on sheep lambs. The results showed that sheep lambs in the SS group exhibited significantly increased (p < 0.05) average daily gain, levels of growth hormone (GH), insulin (INS), IgA and IgM, and cytokines IL-4, IL-10, IL-17, TNF-α and IFN-γ compared to those in the control check (CK) group. Moreover, the SS treatment significantly increased the diversity and abundance of beneficial bacteria, while concurrently diminishing the prevalence of harmful bacteria. Additionally, it modulated various metabolic pathways, promoted lamb growth, improved immunity, reduced the risk of gastrointestinal disease and improved the composition of gastrointestinal microbiota. In summary, our findings highlight the potential of SS treatment in enhancing gastrointestinal health of sheep lambs by improving intestinal function, immunity, and gut microbiome. Consequently, these results suggest that Alhagi camelorum Fisch polysaccharides derived from Shanshan regions holds promising potential as a valuable intervention for optimizing growth performance in sheep lambs.

Feasibility of using bean crop residues for feeding sheep during dry season shortage: implications for economic and environmental resilience

ABSTRACT In Cuba, beans are part of the traditional gastronomy and livelihood of the people. During bean harvest, farmers generate high volumes of stubble, which they burn, thus adversely affecting soil health and organic matter, air quality, and greenhouse gas emissions. Bean harvest occurs during the dry season, a period of feed shortage for livestock, such that integrating farming and livestock production could be a way to feed and fatten sheep at little cost. We assessed the feasibility of feeding bean stubble to sheep by determining 1) volumes produced and nutritional value of stubble, 2) acceptability, performance, and carcass yields of lambs fed stubble, and 3) feasibility for this integrated farming-livestock system at local and regional levels. During harvest, 650 tons of stubble are produced in the municipality of Morón by 190 farmers, which represents a potential to feed more than 3,500 lambs, with acceptable average daily gains of 90 g per day with minimal supplementation. We thus affirm this is a viable technological practice with economic, ecological, and social implications as an acceptable alternative to burning stubble to enhance food security and livelihoods of small and medium-sized farms, while generating new employment opportunities, especially for rural women. Future studies are needed to evaluate the economic, ecological, and social impacts of this agriculture-livestock integration technology.

Effects of Zilpaterol Hydrochloride with a Combination of Vitamin D3 on Feedlot Lambs: Growth Performance, Dietary Energetics, Carcass Traits, and Meat Quality.

This study evaluated the impact of supplementing ZH in combination with D3 on the growth performance, energy efficiency, carcass traits, and meat quality of feedlot lambs. Thirty-two Dorper × Katahdin cross lambs (37.3 ± 5.72 kg) were utilized in a 29 d experiment in a completely randomized block design with a 2 × 2 factorial structure consisting of two levels of ZH for 26 d (0 and 0.20 mg/kg PV-1) and two levels of D3 for 7 d (0 and 1.5 × 106 IU/d-1). ZH improved (p ≤ 0.05) the average daily gain (ADG) and feed efficiency by 9.9% and 17.8%, respectively, as well as hot carcass weight (HCW) and dressing carcass by 4.3% and 2.6%, respectively. (p ≤ 0.03). However, ZH increased (p < 0.01) muscle pH and Warner-Bratzler shear force (WBSF) (2.5 and 23.0%, respectively). D3 supplementation negatively affected (p ≤ 0.02) dry matter intake (DMI) (last 7 d) and ADG by 15.7% and 18.1%. On the other hand, D3 improved the pH of the longissimus thoracis muscle by 1.7% (p = 0.03) without affecting WBSF. When D3 was supplemented in combination with ZH, it was observed that meat quality was improved by reducing muscle pH compared to lambs treated only with ZH. However, D3 did not improve the meat tenderness negatively affected by ZH supplementation.

Performance, digestibility and meat quality from lambs fed diets with plantago lanceolata, Italian ryegrass or sainfoin herbages.

Plantago species, which is known to adapt to different climatic conditions, drought, temperature and different soil types. The aim of this study was to compare the effects of P. lanceolata herbage on fattening performance, rumen variables, digestibility, meat quality, meat nutrients and meat textural variables in lambs with the values of Italian ryegrass and sainfoin herbages. The lambs were fed total mix ration (TMR) with concentrated feed (about 30%) plus forage (about 70%) (P. lanceolata, PLA, Italian ryegrass (Lolium multiflorum); IRY or sainfoin (Onobrychis viciifolia) herbages, SAI). Twenty-four male lambs (Akkaraman breed) were assigned to three treatments with 8 lambs in each group. Fattening performance parameters, digestibility and carcass variables were determined. Meat quality and shelf life variables (oxidation, fatty acid profile and textural variables) was detected in the loin (Musculus longissimus), shoulder (M. deltoideus) and leg (M. semitendinosus) muscle samples, which were rested for 24 h +4°C and stored at -20°C for one week, one month, three months and six months. The dry matter (DM) intake, body weight gain, feed efficiency and carcass yield values of lambs, the DM and organic matter (OM) digestions (DMD and OMD) of TMRs, and the pH value, ammonia-nitrogen and short chain fatty acid (SCFA) concentrations of rumen fluid in lambs consuming PLA were similar to those of IRY and SAI (p > 0.05). PLA increased water holding capacity (WHC) and decreased cooking loss of meat compared to feeding with those of IRY and SAI (p < 0.05). The peroxide value (PV) and malondialdehyde (MDA) concentration increased with the stocking time in the meats (p < 0.05). Therefore, PV and MDA concentrations of shoulder, leg and loin meats up to 6th months for PLA were lower than those of IRY and SAI (p < 0.05). The linoleic acid concentration of loin and shoulder meats in PLA were higher than those of IRY and SAI (p < 0.05). The average oleic acid and ∑ω6 fatty acids concentration of meat in PLA was lower than those in IRY and SAI (p < 0.05). Atherogenic index and thrombogenic index values and palmitic acid levels of meat in PLA were similar to those in IRY, but lower than those in SAI (p < 0.05). Springiness, cohesiveness, resilience, hardness and chewiness values of the textural analysis parameters in meat of PLA were lower than those of IRY and SAI. As a result, effect of P. lanceolata on the fattening performance and rumen fermentation of lambs were similar with those of Italian ryegrass (Gramineae family) and sainfoin (Leguminosae family) forages and, it had a positive effect on meat quality (water holding capacity, cooking loss) and meat shelf life criteria (MDA, PV, fatty acid profile and textural variables). For functional lamb meat production, P. lanceolata can be included in the diet of lamb fattening.

Sainfoin can be included up to 40% in the concentrate of finishing lambs without impairing their performance, rumen fermentation, and carcass quality

Sainfoin (Onobrychis viciifolia) is an excellent forage legume to be included in sheep diets as fresh forage, but its inclusion in concentrates fed to indoor lambs reared has been scarcely studied. This study evaluated the effects of including different levels of dehydrated sainfoin in the concentrates fed to light lambs during the finishing period on animal performance, ruminal fermentation, and carcass traits. Twenty–six weaned male Rasa Aragonesa lambs (14.0 ± 0.49 kg body weight) were randomly grouped and individually fed ad libitum with isoproteic and isoenergetic pelleted concentrates containing 0% (0SF; n=9), 20% (20SF; n=9) or 40% sainfoin (40SF; n=8) for 40 days, from weaning to slaughter. In addition, an in vitro assay was carried out to evaluate the concentrates. The 40SF lambs had a higher dry matter intake (P < 0.01) and tended to show an improvement in average daily gain (P < 0.10). The diet had no effect on carcass weight, dressing percentage, rectus abdominis color or subcutaneous caudal fat color (P > 0.05). Regarding the rumen study, the diet did not affect most ruminal fermentation parameters (P > 0.05), except for pH, which was greater in 40SF lambs than in 20SF lambs (P < 0.05), and the proportion of acetic acid and the acetic:propionic ratio, both of which were higher in 40SF and 20SF lambs than in 0SF lambs (P < 0.01). The results from the in vitro assay showed that the 40SF diet decreased the in vitro dry matter degradability, increased propionic, and decreased butyric proportion compared to 0SF concentrate (P < 0.05), but no effect was obtained for gas, methane, total volatile fatty acids, and ammonia formation among diets (P > 0.05). The lack of detrimental effects on lamb performance and carcass traits suggests that the inclusion of up to 40% sainfoin in the concentrate of light lambs reared indoors would be advisable to promote the use of local forages.

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.

Effect of supplementation of bioactive rich tree leaves on nutrient utilization, growth performance, methane emission and fatty acid profile in finisher lambs fed energy dense diet

To study the effect of supplementing bioactive rich tree foliages in energy dense diet on lamb production and tissue fatty acid profile, 24 weaner male lambs (∼90days old) were divided equally into 2 groups and fed complete feed blocks without (C) and with 6% Hardwickia binata (anjan tree) leaves (T). Feed blocks in both the groups consisted of 3.25% rumen bypass fat. Dry matter intake and plane of nutrition were comparable among the groups but digestibility of neutral and acid detergent fibre were lower (P<0.05) in T than C. Rumen fermentation attributes revealed higher (P<0.05) concentration and proportion of propionic acid and total volatile fatty acids in T compared to C. The metagenomic equivalent values of total methanogens and protozoa were lower (P<0.05) while, population of Butyrivibrio fibrisolvens was higher in T compared to C. Loss of metabolizable energy through methane was reduced by 4.6 percentage points in T than C which resulted in higher microbial nitrogen synthesis in T from methane mitigation. Subsequently, the average daily gain in lambs was improved by 5.9% in T compared to C. The fatty acid profile of Longissimus thoracis muscle revealed higher (P<0.05) C18:2c9t11 content in lambs of T group than C. Hence, from the present findings it can be concluded that inclusion of Hardwickia binata leaves at 6% level increased condensed and hydrolysable tannin content of the diet which modestly affected rumen fermentation resulting in reduced methane production and enhanced conjugated linoleic acid content in muscle tissue.

Effect of urea-treated rice straw, mixed with faba bean straw, on nutrient digestibility, blood metabolites and performance of growing lambs.

The present study aimed to use poor quality roughages,such as rice and faba bean straw, treated with or without urea, and their impacts on digestibility, rumen fermentation, some blood parameters, and growth performance of lambs. Twenty crossbred male lambs (1/4Finland ×¾ Ossimi, 25±1.13kg live body weight) were chosen and divided into four groups. All lambs were fed rations of concentrated feed mixture at 2% of live weight with the following roughages ad libitum: URS (control group, untreated rice straw), TRS (urea-treated rice straw), FBS (faba bean straw), and TRS+FBS (mixture of TRS and FBS,1:1). Nutrient digestibility and feeding values improved (P<0.05) with TRS+FBS lambs versus FBS, TRS and URS lambs. The highest numerical values of ruminal total volatile fatty acid (VFA) concentration in TRS lambs were recorded 23.9ml.eq/dl followed by TRS+FBS, URS and FBS. Regarding to the ruminal parameters, there were no differences (P>0.05) among evaluated groups except for NH3-N, the highest concentration (P<0.05) was recorded in TRS lambs at 3h post-feeding. Lambs of TRS, FBS and TRS+FBS showed faster growth (P<0.05) than those of the control (i.e., URS). Intakes of dry matter, total digestible nutrients, and digestible crude protein were numerically increased for TRS, FBS, and TRS+FBS. Feed conversion, as kg dry matter/kg gain, was improved for TRS, FBS, and TRS+FBS lambs versus URS. Daily gain of lambs increased (P<0.05) with lambs of TRS, FBS, and TRS+FBS but URS lambs showed a decrease (P<0.05) in daily gain. Feed conversion as kg dry matter intake/kg gain was improved (P<0.05) by feeding on TRS, FBS and TRS+FBS rations versus URS. The TRS+FBS lambs tended to have the highest economic efficiency versus URS, TRS and FBS lambs. It was concluded that urea-treated rice straw could be used as sole roughage or mixed with faba bean straw (1:1) in growing lambs' ration to improve their performance and economic efficiency without adversely affecting their health.The present study aimed to use poor quality roughages,such as rice and faba bean straw, treated with or without urea, and their impacts on digestibility, rumen fermentation, some blood parameters, and growth performance of lambs. Twenty crossbred male lambs (1/4Finland ×¾ Ossimi, 25±1.13kg live body weight) were chosen and divided into four groups. All lambs were fed rations of concentrated feed mixture at 2% of live weight with the following roughages ad libitum: URS (control group, untreated rice straw), TRS (urea-treated rice straw), FBS (faba bean straw), and TRS+FBS (mixture of TRS and FBS,1:1). Nutrient digestibility and feeding values improved (P<0.05) with TRS+FBS lambs versus FBS, TRS and URS lambs. The highest numerical values of ruminal total volatile fatty acid (VFA) concentration in TRS lambs were recorded 23.9ml.eq/dl followed by TRS+FBS, URS and FBS. Regarding to the ruminal parameters, there were no differences (P>0.05) among evaluated groups except for NH3-N, the highest concentration (P<0.05) was recorded in TRS lambs at 3h post-feeding. Lambs of TRS, FBS and TRS+FBS showed faster growth (P<0.05) than those of the control (i.e., URS). Intakes of dry matter, total digestible nutrients, and digestible crude protein were numerically increased for TRS, FBS, and TRS+FBS. Feed conversion, as kg dry matter/kg gain, was improved for TRS, FBS, and TRS+FBS lambs versus URS. Daily gain of lambs increased (P<0.05) with lambs of TRS, FBS, and TRS+FBS but URS lambs showed a decrease (P<0.05) in daily gain. Feed conversion as kg dry matter intake/kg gain was improved (P<0.05) by feeding on TRS, FBS and TRS+FBS rations versus URS. The TRS+FBS lambs tended to have the highest economic efficiency versus URS, TRS and FBS lambs. It was concluded that urea-treated rice straw could be used as sole roughage or mixed with faba bean straw (1:1) in growing lambs' ration to improve their performance and economic efficiency without adversely affecting their health.

Effects of Breeding Practices on Reproductive Efficiency of Ewes and Fattening Performance of Lambs

In this study, the data obtained by questionnaire from small ruminant farms in Tekkeköy district of Samsun province were evaluated. Among the enterprises in the study, 50% of them breed Karayaka sheep, and 33.4% of them breed Bafra sheep. It was determined that 95.8% of the farmers applied flushing before ram siring, 83.3% of the farmers applied feed supplements to the ewes after birth, 95.8% of the farmers applied additional vitamin supplements to the lambs, and 83.3% of the farmers used salt-containing licking stones for the lambs. In the study, internal and external parasites were applied to the lambs to be fattened in all of the farms, and all of them were not released to pasture until sale. Winter lambs were fattened in 91.7% of the farms. The average age of the breeders is 50, and 1.08 rams are sired in an average year in the farms. The average age of lambs sent to slaughter is 4 months, and the average carcass weight at slaughter is 19.15 kg. Feed supplementation to the ewes after birth and application of salt-containing licking stones to the lambs had a positive effect on the average carcass weight of the fattened lambs. In this study, it was determined that winter lambs were preferred more than summer lambs. According to this result, by fattening winter lambs in this period when there is no pasture opportunity, both seasonal meat needs can be met, and it provides the opportunity to sell at high prices in the winter period. In this case, the breeder will earn more income.

Supplementation of feedlot lambs with magnesium oxide and sodium bicarbonate: Effects on performance, nutrient digestibility, rumen environment, serum biochemistry and antioxidant indices

The present experiment was conducted to obtain an appropriate addition strategy of magnesium oxide (MgO) for feedlot lambs and to elucidate how the combined addition of MgO and sodium bicarbonate (NaHCO3) influences the growth performance and carcass characteristics of feedlot lambs. Sixty male Dorper-Hu hybrid lambs (32.76 ± 0.85 kg) were randomly assigned to 20 pens (3 lambs per pen; 5 pens per treatment). Lambs received a corn-based total-mixed ration (TMR, 80:20 concentrate to forage) without supplementation (CON) or with the inclusion (dry matter basis) of 15 g/kg NaHCO3 (SB), 2.5 g/kg MgO + 7.5 g/kg NaHCO3 (MG1) or 5 g/kg MgO + 7.5 g/kg NaHCO3 (MG2). Buffer addition effectively increased ruminal pH and water intake in feedlot lambs (P < 0.01). The MG2 group had lower dry matter intake (P ≤ 0.03), while the MG1 group showed higher average daily gain and lower feed-to-gain ratio than the other groups (P < 0.01). Compared to the CON and SB groups, MG1 and MG2 groups had greater total tract nutrient digestibility, except for the stage 1 of DM and ADF (P < 0.01). Adding MgO with NaHCO3 improved total volatile fatty acids concentration (P < 0.01). Microbial community analysis revealed enhanced Prevotella abundance in both MG1 and MG2 groups (P = 0.04). Additionally, MG1 and MG2 groups also both exhibited greater serum antioxidant capacity compared to CON and SB groups (P ≤ 0.03). The MG1 group showed greater dressing percentage, and ribeye area than other groups (P < 0.01). Overall, the recommended supplementation strategy for the lambs' diet was 2.5 g/kg MgO + 7.5 g/kg NaHCO3. The mixture of MgO and NaHCO3 enhanced the total tract nutrient digestibility, rumen fermentation, and serum antioxidant capacity in lambs, resulting in improved lamb growth and carcass performance.

Performance, carcass characteristics, and meat quality of lambs fed diets containing crude glycerin

The aim of this study was to evaluate the effects of four crude glycerin levels in the diet of feedlot lambs on performance, carcass characteristics, and meat quality. Forty three-month-old crossbred Santa Inês x Dorper lambs weighing 18.2 ± 0.169 kg were used in a completely randomized design, with four diets and 10 replicates per diet. The animals were housed in individual pens. The trial period (42 days) was preceded by 14 days of adaptation to handling and diet. Final body weight (FBW), empty body weight (EBW), average daily weight gain, feed conversion, and feed efficiency did not differ with crude glycerin levels in the diet. Nutrient intake (dry matter (DM), ether extract (EE), crude protein (CP), and neutral detergent fiber (NDF)) did not differ depending on crude glycerin levels. In the evaluation of carcass characteristics, there was a quadratic effect due to crude glycerin levels on hot carcass yield (maximum point- maxP = 9.73%), leg perimeter (maxP = 9.45%), fat thickness (maxP = 7.41%), and leg weight (maxP = 8.69%). Loin weight and conformation showed a linear increase as a function of crude glycerin levels. The other studied variables were not affected by crude glycerin levels in the diet. In the non-carcass components, the full gastrointestinal tract, mesenteric fat, omental, and perirenal fat were not influenced by crude glycerin levels. Regarding meat quality, no effects were observed on the parameters evaluated in the longissimus dorsi. The addition of up to 15% crude glycerin in the lamb's diet does not affect its performance, however, the addition of up to 8% improves carcass characteristics and maintains meat quality.

Effects of Sugarcane-Derived Polyphenol Supplementation on Methane Production and Rumen Microbial Diversity of Second-Cross Lambs.

The objective of this study was to evaluate the effects of feeding sugarcane-derived polyphenolic supplement (Polygain, The Product Makers Australia, Keysborough, VIC, Australia) on enteric methane (CH4) emission, rumen microbiota, and performance of second-cross lambs. For this purpose, 24 Poll Dorset × (Border Leicester × Merino) lambs were allocated to 3 different treatments: Control (C), 0.25% Polygain (0.25 PG), and 1% Polygain (1 PG) diets with a uniform basal feed (25% cracked wheat grain, 25% cracked barley grain, 25% oaten chaff, 25% lucerne chaff). Both doses of Polygain reduced the total CH4 production (g/day; p = 0.006), CH4 yield (CH4, g/kg of dry matter intake; p = 0.003) and CH4 intensity (CH4, g/kg of BW; p = 0.003). Dry matter intake tended to be greater (p = 0.08) in sheep fed 1 PG compared to the C group, with the 0.25 PG group being intermediate. The average daily gain of the lambs was improved (p = 0.03) with 1% Polygain supplementation. The relative abundance of genera Methanobrevibacter_unidentified, Methanomethylophilaceae_uncultured, Methanogenic archaeon mixed culture ISO4-G1, Methanosphaera uncultured rumen methanogen, Methanogenic archaeon ISO4-H5, and Methanobrevibacter boviskoreani JH1 were reduced with Polygain supplementation. In conclusion, feeding Polygain reduced lambs' enteric CH4 emissions, altered the rumen microbiome, and improved the growth performance of lambs.

Additive Impacts of Liveweight and Body Condition Score at Breeding on the Reproductive Performance of Merino and Non-Merino Ewe Lambs.

Ewe lambs that are heavier due to improved nutrition pre- and post-weaning achieve puberty at a younger age, are more fertile, and have a higher reproductive rate. Fatness is intimately linked to reproduction, and we hypothesised that higher body condition scores at breeding would have positive effects on the reproductive rate of ewe lambs over and above liveweight. We also expected that if only a proportion of ewe lambs were presented for breeding, then it would be more effective to select them based on both liveweight and body condition score. To test these hypotheses, we analysed data from over 17,000 records from Merino and non-Merino ewe lambs from 22 different flocks across Australia. Non-Merino ewe lambs were more fertile (69.4% vs. 48.7%) and achieved a higher reproductive rate than Merino ewe lambs (96.9% vs. 60.7%). There were significant curvilinear relationships between liveweight (p < 0.001) or body condition score (p < 0.001) prior to breeding and reproductive rate for both Merino and non-Merino ewe lambs. For both breeds, there was a significant (p < 0.001) quadratic effect of body condition score prior to breeding on reproductive rate, independent of the correlated changes in liveweight, and at the same liveweight, an extra 0.5 of a body condition score up to 3.3 improved reproductive rate by about 20%. Nevertheless, the results indicated that if only a proportion of ewe lambs were selected for breeding, then selection based on both liveweight and body condition scores may only improve the overall reproductive rate by 1 to 2% compared to selection based on liveweight alone. We conclude that liveweight is a more effective method than body condition score for selecting ewe lambs for breeding.

Effects of Feed Ingredients with Different Protein-to-Fat Ratios on Growth, Slaughter Performance and Fat Deposition of Small-Tail Han Lambs.

The purpose of this study was to investigate the effects of feed ingredients with different protein-to-fat ratios on growth, slaughter performance and meat quality of Small-Tail Han lambs. Forty-five Small-Tail Han lambs (♂) (BW = 34.00 ± 2.5 kg, age = 120 ± 9 d) were randomly divided into groups with three different experimental treatments: (1) PF 5, with the ratio of protein to fat (CP:EE) of 50 to 5; (2) PF10, CP: EE = 50:10; (3) PF20, CP: EE = 50:20. Each treatment group had 15 lambs, and each sheep was a repeat. This experiment lasted for 65 days, with feed intake recorded daily, and animals being weighed on days 0, 30, and 65. At the conclusion of the experiment, eight lambs from each group were slaughtered to assess slaughter performance and meat quality. The results showed that the average daily gain (ADG) of the three groups were 315.27, 370.15 and 319.42 g/d, respectively. The PF10 group had the highest ADG (370.15 g) (p < 0.05). Forestomach weights (1216.88 g) of the PF10 group were significantly higher than those of the other groups (p < 0.05). There were no differences (p > 0.05) in fat percentages in various parts of body among treatments. Feed conversion of the PF10 group was higher (p < 0.05) than that of PF 5 and PF 20 groups. Furthermore, the PF10 group had a higher (p > 0.05) carcass weight and slaughter rate and there were few differences between the other groups in terms of dry matter intake, meat quality, organ weight, and fat deposition (p > 0.05). The protein-energy supplement with protein-to-fat ratio, PF10 appeared to be more desirable to promote the growth and development in Small-Tail Han Lambs.