Male Lambs Research Articles

Dietary energy level and β2-adrenergic agonist supplementation on growth performance, dietary energy, carcass traits, and visceral mass of hairy lambs

Context The beta-agonist zilpaterol (ZH) is a feed additive that improves growth performance via protein accretion during the finishing phase of ruminant fattening. However, evaluating the possible interaction between ZH and nutrients of the diet has received limited attention. Aims We investigated the changes in growth performance and carcass traits in response to ZH supplementation of hairy lambs fed finishing diets with different energy concentration. Methods Forty-eight Pelibuey × Katahdin crossbred male lambs (43.8 ± 6.3 kg) were used in a 34-day feeding trial to evaluate the interaction between diet energy density [8.37 (LE) and 8.79 (HE) MJ of net energy for maintenance (NEm) per kilogram of diet] and zilpaterol hydrochloride supplementation (ZH, dosed at 0 or 6 mg ZH/kg) on growth performance, carcass traits, and visceral mass. All diets contained 14.5% crude protein (CP). Key results There was no interaction of energy level and ZH in any of the variables evaluated. HE increased average daily gain (ADG) and gain efficiency (GF) without affecting the observed-to-expected dietary NE. Zilpaterol supplementation increased ADG, GF, and observed-to-expected dietary NE. Both HE and ZH increased carcass weight. HE increased carcass fat, whereas ZH decreased it. HE increased dressing percentage. ZH increased longissimus muscle area, the muscle:fat ratio in the shoulder, and leg whole-cut proportion. Visceral mass was not affected by energy level. ZH decreased visceral fat. Conclusions Increasing diet energy from 8.37 to 8.79 MJ NEm/kg enhanced growth performance and carcass traits but did not improve dietary energy utilization. Supplemental ZH enhanced growth performance, dietary-energy utilization and carcass traits of lambs. Implications ZH supplementation is a tool to enhance growth performance by improving protein accretion and reducing carcass fat. Response to ZH supplementation is independent of the differences in energy density of finishing diets.

Impact of Providing Cowpea (Vigna unguiculata) Hay, Wheat Bran, and Their Mixes on Begait Lambs' Skin and Leather Quality

Aims: To evaluate the impact of adding wheat bran (WB), cowpea hay (CPH), or mixes of the two on the chemical and physico-mechanical properties of leather. To determine the ideal ratio for supplementing wheat bran and cowpea hay on the chemical and physico-mechanical properties of leather. Study Design: The study employed a randomized complete block design (RCBD) with five treatments and blocks. Place and Duration of Study: Northern Ethiopia, Humera Agricultural Research Center farm, starting from December 2016 until November 2017. Methodology: 25 intact male Begait lambs were bought from the local market, weighing an average of 28.02 ± 1.49 kg (mean ± SD) at 5 to 6 months of age. Based on their starting body weight, they were split into five groups and assigned randomly to each of the five treatments. The standard diet for T1, T2, T3, T4, and T5 consisted of giving natural grass hay ad libitum plus supplements of 300 g CPH, 225 g CPH + 75 g WB, 150 g CPH + 150 g WB, 75 g CPH + 225 g WB, and 300 g WB DM day-1. Three lambs per treatment were randomly chosen, slaughtered, and dressed down using standard commercial techniques at the end of the feeding trial to assess the quality of skin and leather. Results: Compared to the other treatment groups, the Begait lambs in T2 and T3 exhibited increased tensile strength, elongation strength, and thickness. However, the chemical makeup of skin was comparable between treatment groups. Conclusion: Therefore, this study concluded that all test diets generated skin and leather that largely complied with the chemical and physico-mechanical quality standards demanded by the leather industry.

The Multi-Loci Genotypes of the Myostatin Gene Associated with Growth Indicators of Intensively Fattened Lambs of Latvian Sheep.

Myostatin (MSTN), a member of the TGFβ superfamily, negatively affects skeletal muscle growth and controls muscle development at stages of pre-natal muscle growth. Marker-assisted selection with molecular markers of the MSTN gene can be used in animal husbandry for higher-quality and more economically profitable lambs. The study aims to identify multi-locus genotypes within the MSTN gene regions as molecular markers for fattening, feed efficiency, and carcass traits in Latvian sheep. This analysis was conducted on 76 intensively fattened male lambs representing six breeds in Latvia. Nine genotypes were identified based on four SNPs in the promoter and exon 1 regions, while six and four SNPs in introns 1 and 2 led to the formation of 14 and 10 genotypes, respectively. Six genotypes identified in the 3'UTR were significantly linked to traits such as birth weight, slaughter yield, muscle development, fat depth, average daily gain, dry matter intake, and feed efficiency. Genotypes of intron 1 were associated with slaughter yield, while genotypes of intron 2 were linked to fat depth, dry matter intake, and residual weight gain. The study concludes that MSTN gene SNPs can be used in selection to enhance sheep breeds in Latvia and improve economic outcomes for breeders.

Growth performance and body composition of feedlot lambs fed refused melon fruit.

This study aimed to evaluate the effect of replacing corn grain with refused melon fruit (RMF) in the diet on the intake and digestibility of nutrients, performance, carcass characteristics, and physical-chemical attributes of meat from lambs finished in feedlot. We used 30 male lambs of the Santa Inês breed, not castrated, with 18.3 ± 1.1kg body weight and 120 days of life, feedlot in individual stalls for 71 days. The animals were fed at will with treatment diets containing 0g/kg (control, without RMF), 100, 200, 300, or 400g/kg of RMF in the dry matter of the total diet, in a forage: concentrate ratio of 30:70. There was a significant decrease (P < 0.05) in the intake of dry matter, neutral detergent fiber, non-fibrous carbohydrates, and metabolizable energy of the lambs receiving diets with the inclusion of RMF. The inclusion of RMF significantly decreased (P < 0.05) the final weight, average daily gain, and gross feed efficiency but did not influence (P > 0.05) the carcass weight and tissue composition of the shoulder. There was no significant effect (P > 0.05) of the inclusion of RMF on the physical-chemical characteristics of the meat, but the moisture content of the meat increased significantly (P < 0.05) with increasing RMF in the diet. We recommend including up to 300g/kg of RMF in diets for lambs formulated to gain 0.2kg/day and with a 30:70 forage: concentrate ratio.

The liveweight, carcasses and meat quality of intact and castrated male lambs reared under a pasture-fed Australian production system

Context Intact male (ram) lambs are often discounted by meat processors because of their perceived defective meat quality. Aims This study quantified the effects of castration on the liveweight, growth, carcass parameters and the meat quality of male lambs. Methods Liveweight, growth and carcass data were collected from 133 ram and 132 castrated (wether) lambs reared under a pasture-fed production system. A total of 50 lambs were subsequently selected, balanced by final curfew liveweight and castration status, to investigate additional carcass, meat quality, consumer sensory panel scores and colour stability parameters. Key results It was found that total average daily gains for ram lambs were highest (242.9 ± 5.2 g/day; P = 0.002), resulting from their higher pre-weaning growth rate of 327.7 ± 9.7 g/day (P &lt; 0.001). Wethers were fattier, having higher estimated intramuscular fat (3.9 vs 3.3 ± 0.1%, respectively) and subcutaneous fat depth (14.7 vs 13.5 ± 0.4 mm, respectively) than ram lambs. Purge loss (P &lt; 0.030) and ultimate pH (P &lt; 0.035) were higher for the meat of wether lambs, but only after 32 days of wet ageing. Consumers scored the meat of wether lambs as significantly more tender (61.0 vs 54.6 ± 2.3%; P = 0.005) and of greater overall liking (65.1 vs 61.1 ± 2.0%; P = 0.044) than that of ram lambs. These, and a comparison of shear force, near infrared spectroscopy for intramuscular fat content and retail colour with consumer thresholds, suggest a general satisfaction with ram and wether lamb meat quality. Conclusions Collectively, there seems to be few tangible performance and meat quality advantages to the castration of male lambs. Implications Prime lamb producers must consider flock management and market preference when deciding on best practice.

Targeted metabolomics analysis of fatty acids in lamb meat for the authentication of paper mulberry silage as a substitute for alfalfa silage

BackgroundThe paper mulberry (Broussonetia papyrifera L.) is a valuable source of woody forage that can be used for ruminants, such as goat and lambs. However, there is limited knowledge about how paper mulberry silage affects carcass characteristics, meat physicochemical attributes, amino acid and unsaturated fatty acids in Hu lambs compared to alfalfa silage. The objective of this experiment was to investigate the impact of substituting alfalfa silage with paper mulberry silage on the slaughter performance, meat quality, free amino acid and fatty acid composition in muscles of Hu lambs.ResultsThirty 60-day-old male Hu lambs with 17.13 ± 0.26 kg body weight were randomly allocated into paper mulberry silage (30% of total mixed ration) and alfalfa silage (30% of total mixed ration) treatment, and the feeding trial lasted 70 days. The results indicated no significant differences in all measurements (P > 0.05). However, compared to the group fed with alfalfa silage, the group fed with paper mulberry silage exhibited a reduction in meat drip loss (P < 0.05) without any notable effect on meat nutrients (P > 0.05). Targeted metabolomics analysis revealed that feeding paper mulberry silage led to decreased levels of certain bitter amino acids, such as valine, leucine, isoleucine, tryptophan, and phenylalanine (P < 0.05). Furthermore, the consumption of paper mulberry silage significantly augmented the levels of monounsaturated and polyunsaturated fatty acids, particularly n6-polyunsaturated fatty acids (C18:2n6, C20:3n6, C20:4n6, etc.), in meat.ConclusionsSubstituting paper mulberry silage for alfalfa in the daily diet of Hu lambs not only has no detrimental effect on animal performance but also improves meat unsaturated fatty acid composition.Graphical

High-concentrate diet supplemented with hydrolysable tannin improves the slaughter performance, intestinal antioxidant ability and barrier function of fattening lambs.

The objective of current experiment was to study the potential influence of hydrolysable tannin supplementation on slaughter performance, meat quality, intestinal digestive enzyme activity, antioxidant ability and barrier function in fattening lambs. In total, 36 male Hu sheep lambs with similar body weight (15.83 ± 0.48 kg) and days in age (55 ± 2 d) were randomly assigned to one of three groups of 12 animals each: control without tannin (CON) and tannin supplementation groups (TA1, 3 g/d per lamb; TA2, 6 g/d per lamb). All the lambs were reared in individual hutches, and the experiment lasted for 60 d. On d 61, 8 lambs from each group were randomly selected to slaughter. Results showed that the serum diamine oxidase and lipopolysaccharide contents of TA2 group were higher (p < 0.05) than those of CON group. Compared with CON group, the carcass weight and intramuscular fat content of lambs in TA1 group were increased (p < 0.05) and the meat shear force was decreased (p < 0.05). The trypsin activity in the jejunum and ileum of TA1 group was higher (p < 0.05) than that of CON and TA2 groups. Also, tannin supplementation significantly increased (p < 0.05) the level of jejunal and ileal total antioxidant capacity and reduced (p < 0.05) the jejunal malondialdehyde concentration in lambs. The jejunum and ileum of TA1 lambs showed reduced (p < 0.05) tumor necrosis factor-alpha and increased (p < 0.05) interleukin-10 mRNA levels compared with CON lambs. In the jejunum, the secretory immunoglobulin A content of TA1 group was higher (p < 0.05) than that of CON and TA2 groups. Lambs supplemented with tannin at the level of 3 g/d increased (p < 0.05) the gene expressions of claudin-1, claudin-4 and zonula occludens-1 in the jejunum when compared to those of CON and TA2 groups. In summary, tannin supplementation at the level of 3 g/d per animal can improve the production performance and intestinal function of fattening lambs fed a high-concentrate diet.

Growth Performance, Dietary Energetics, Blood Metabolites, Carcass Traits, Meat Quality, and Gene Expression of Lambs Supplemented with a Polyherbal Phytogenic Additive

This study aimed to evaluate the effects of supplementation with a polyherbal phytogenic additive (PPA) on the productive performance, dietary energetics, blood metabolites, carcass traits, meat quality, and gene expression of finishing lambs. Thirty-six male Pelibuey lambs (23.61 ± 0.57 kg body weight (BW)) were housed in individual pens and assigned to four treatments (n = 9) with different doses of PPA: 0 (CON), 2.5 (PPAL), 5 (PPAM), and 7.5 (PPAH) g of PPA/kg of DM for 56 days. Average daily gain, dry matter intake, and observed dietary net energy for maintenance and weight gain increased linearly (p &lt; 0.05) in lambs supplemented with PPAH. A linear reduction (p = 0.02) in FCR was detected in lambs fed PPAM and PPAH. The PPAH supplementation linearly increased (p &lt; 0.001) Longissimus dorsi muscle area, but other carcass traits were not affected (p &gt; 0.05) by PPA doses. The physicochemical characteristics of the meat and the hematological parameters of the lambs were not affected (p &gt; 0.05) by the PPA doses. The glucose, uric acid, creatinine, and bilirubin serum concentrations decreased linearly (p &lt; 0.05) in lambs supplemented with PPAM and PPAH. Gene ontology analyses showed that nine biological processes were modified (p &lt; 0.05), including DNA replication, drug metabolism–cytochrome P450, oxidative phosphorylation, and chemical carcinogenesis–reactive oxygen species. In conclusion, high doses (7.5 g/kg DM) of PPA can improve growth performance and dietary energy utilization efficiency in finishing lambs. Likewise, gene expression analysis indicates that supplementation with high doses of PPA could improve energy production and antioxidant status in finishing lambs.

Determination of the nutritional potential and valorization of saffron (Crocus sativus L.) wastes as an antioxidant agent in ruminant feeding: in vitro and in vivo studies.

Saffron (Crocus sativus L.) is a plant known for its diverse medicinal and nutritional properties, which has adapted well to arid and semi-arid regions of the world, particularly in the Middle East. Research on saffron wastes (SW) as a dietary additive for small ruminants is limited. Therefore, two primary experiments were designed to evaluate the nutritional potential of SW. In the first trial, the nutritional value of SW collected from various regions in northeast Iran was assessed through proximate analysis and in vitro procedures. In the second trial, the effects of incorporating SW (a 1: 1 mixture from all regions, w: w) at two levels (30 and 60g/day) into the diets of Afshari male lambs were investigated in comparison to a control diet. Except for dry matter and ether extract contents, other chemical and mineral compounds varied among the SW collected from different regions. The samples displayed diversity in potential gas production and estimated dry matter intake (DMI). In the in vivo experiment, DMI, nutrient digestibility, and most blood metabolites were not significantly affected by the addition of SW; however, malondialdehyde, total antioxidant capacity, and cholesterol levels were respectively decreased, increased, and decreased in lambs fed 60g SW/day compared to the control group. Overall, SW collected from various regions demonstrated different nutritional values. Although the dietary inclusion of SW at the level of 60g/day did not adversely effect on DMI, nutrient digestibility, or certain blood metabolites, it is suggested for its potential improvement in lambs' health indicators. Long-term studies are recommended for future SW evaluation in vivo.

Effect of Replacing Barley Grain by Urea in the Diet of Iraqi Lambs

This study conducted to seeks the effects of partially changing barley grain (BG) with different levels amount of urea on growth performance, rumen fermentation, nutrient digestion and blood parameters in fattening lambs. Twelve Awassi male lambs were divided according to body weight (BW) into three equal groups (4 lambs per each group) and housed in individual pens and assigned to one of three dietary treatments in a randomized block design: barley grain (BG)were given to animals according to the body weight of lambs (3 % of BW) and (BG) reduced and replace with 0, 10, 20, gm urea. Compared with the control the lambs fed the reduced GB diet plus urea was higher (p &lt; 0.01) concentrations of ruminal ammonia and increased with increasing the urea supplementation. As well as increased the crude protein (CP) intake , blood urea nitrogen (BUN), final BW, dry matter intake (DMI) and average daily gain (ADG) were observed with the increasing urea addition to the diet, results showed that 10 gm of urea could substitute of 10 gm BG per kg feed DM without any negative effect on health performance of fattening lambs when fed urea.

Effect of Long-Term Supplementation of AZOMITE (Hydrated Sodium Calcium Aluminosilicate) in Finishing Diets on Growth Performance, Dietary Energy, and Carcass Yield of Hairy Lambs.

The aim of this study was to evaluate growth performance, dietary energy utilization, and carcass characteristics (carcass weight, dressing percentage, and visceral organ mass) of feedlot lambs fed different levels of AZOMITE (AZO), a source of volcanic clay composed of hydrated sodium calcium aluminosilicate, the same as that included in a finishing diet. For this reason, 36 Pelibuey × Katahdin crossbred intact male lambs (18.81 ± 3.04 kg initial weight) were used in a feeding trial lasting 81 d. Lambs were grouped by initial weight and assigned within six weight groupings to 18 pens in a randomized complete block design. Diets, offered ad libitum, were corn-based finishing diets with an 88:12 concentrate-to-forage ratio supplemented as follows: 1) no AZO inclusion (CTRL), 2) AZO inclusion at a 0.75% level (0.75AZO) in diet dry matter, 3) AZO inclusion at a 1.50% level (1.5AZO) in diet dry matter. Cracked corn was replaced by AZO. After the feeding trial was finished, lambs were slaughtered and carcass weight was registered and dressing percentage was calculated. The data were analyzed as a randomized complete block design, with the pen as the experimental unit. Water consumption and dry matter intake were not affected (p ≥ 0.11) by supplemental AZO. The incorporation of AZO into the diet increased gain efficiency and observed dietary net energy (NE), being maximal with 0.75% AZO inclusion (quadratic effect, p = 0.02). The observed-to-expected dietary NE in the control group was as anticipated (1.00) according to the estimated energy based on the ingredient composition in diet, while in the 0.75AZO group, the observed dietary energy was 6% above expected, indicating a greater efficiency in energy utilization destined to growth (quadratic effect, p = 0.006). Lambs that were fed the AZO treatment showed an improvement (linear effect, p = 0.04) in hot carcass weight (HCW), and tended (linear effect, p = 0.06) to improve dressing percentage (DP) as AZO was increased in the diet. Visceral organ mass was not affected by the treatments. It is concluded that AZOMITE clay can be included up to 1.5% in finishing diets for lambs without negative effects on the intake of water and feed. Lambs that received diets supplemented with 0.75% AZO showed greater improvements in feed efficiency and dietary energy utilization, but an inclusion of 1.50% resulted in greater improvements to HCW and DP. This is the first report regarding the effects of AZO supplementation in the dietary energy utilization of fattening hairy lambs. Further research about the effects of AZO supplementation on ruminal and total tract digestion, carcass and meat quality, and the health of lambs is needed in order to more deeply understand the effects of AZO on its productivity performance.

Congenital Right-side Rib Agenesis in a Male Lamb: A Rare Case Report

Sheep play a vital role in agriculture, contributing to Gross Domestic Product (GDP) through meat, wool, and leather. The number of ribs in sheep is an important economic trait, particularly for meat production, as a higher rib count correlates with increased mutton yield. However, the congenital absence of ribs is a rare condition scarcely documented in veterinary field. This report presents the first known case of rib aplasia in a lamb, highlighting its clinical presentation, diagnosis, and implications. A two-day-old male co-twin lamb exhibited symptoms of ataxia, anorexia, and dyspnea. Physical examination revealed missing ribs on the right side and scoliosis at the thoracic vertebrae level. Chest X-rays confirmed the absence of the 9th and 10th ribs and thoracic scoliosis. Despite explanations of the poor prognosis, the lamb collapsed after two days, and no post-mortem examination was conducted. This case underscores the need for further research to identify genetic factors contributing to congenital rib agenesis in lambs, given its economic importance in the sheep industry.

Supplementing exogenous xylanase improves the liver antioxidant capacity and immune response of Tibetan sheep fed wheat-based diets

Xylanase is a heteropolysaccharide found in the plant cell wall, which aids in the absorption and utilisation of nutrients. When embedded in animal feed, it enhances nutrient availability, leading to improved animal performance. The aim of this study was to explore the effect of xylanase supplementation in wheat-based feeds on the hepatic development, antioxidant capacity, and immune response in Tibetan sheep. Sixty healthy, weaned, non-neutered male lambs (19.35 ± 2.18 kg) were randomly assigned to two equal groups (n = 30 per group). Dietary treatments were: basal diet (H group), and basal diet with 0.2% xylanase supplementation (E group). After a 10–day adaptation period, the feeding trial was carried out for 90 days. The live weight, morphology, antioxidant capacity and immune response were measured. The differential genes in liver were identified by RNA-sequencing. Our results showed that the levels of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) were significantly higher in E group than in H group (p < 0.05). Enzyme-linked immunosorbent assay (ELISA) revealed that immunoglobulin A (IgA), IgM, and IgG were significantly higher in E group than in H group (p < 0.05). The hepatocytes of sheep fed xylanase diet showed arranged radially into hepatic plates cantered around the central vein, and the plates linked with each other to form a lost-like structure. A total of 4,509 differential genes (DEGs) were identified, among which 4,427 were up-regulated and 82 down-regulated. Additionally, the expression of antioxidant-related genes in cluding catalase (CAT), superoxide dismutase 1 (SOD1), oxidation resistance 1 (OXR1) and glutathione peroxidase 2 (GPX2), and immunity-related gene including mitogen-activated protein kinase 1 (MAPK1), signal transducer and activator of transcription 5B (STAT5B), janus kinase 3 (JAK3) and jun proto-oncogene (JUN) were verified using the quantitative reverse transcription polymerase chain reaction (qRT-PCR). Conclusion: In conclusion, dietary 0.2% xylanase supplementation promoted hepatic antioxidant capacity and immune response via modulating the expression of functional genes in Tibetan sheep.

The Effects of Corn Silage and Sunflower Silage and Their Mixtures at Different Levels on the Fattening Performance of Kıvırcık Lambs

Maize silage is widely used in the nutrition of ruminants worldwide. Nevertheless, maize is expensive and difficult to grow in cold and arid climates. To investigate the effects of feeding pure maize silage and different mixtures of maize and sunflower silages on the fattening performance of lambs. In the study, 40 Kıvırcık male lambs aged 2.5-3 months and with an average live weight of 23-25 kg were used as the animal material. The experiment was carried out for 56 days in a semi-open barn. In accordance with the experimental design, animals were divided into 5 different silage groups (100 maize silage, 75 maize silage+25 sunflower silage, 50 maize silage+50 sunflower silage, 25 maize silage+75 sunflower silage, 100% sunflower silage), so that there would be 8 lambs in each group. The lambs were housed in individual compartments during the experiment and fed individually. Silages were given ad libitum, and additional 700, 900, and 1,400 g concentrated feed was given daily between the 0th and 21st, 21st and 42nd, and 42nd and 56th days, respectively. During the fattening period, the values of live weight, daily live weight gain, feed consumption, and feed conversion ratio were determined. The differences among the live weight values of different silage groups during the trial period were found to be not significant (p&gt;0.05), and the values obtained at the end of 8 weeks varied between 35.94 and 37.44 kg. The silage consumption of lambs fed different silage types showed significant differences (p

The effect of pre-partum shearing of Corriedale ewes on placental and lamb development and neonatal behaviour.

To evaluate the effects of early and late pre-partum shearing of Corriedale ewes carrying single fetuses on placental and lamb development and neonatal lamb behaviour. At 70 days of gestation, 37 multiparous Corriedale ewes with known gestation dates were randomly allocated into three groups: S70 (n = 12) and S110 (n = 12), shorn at Day 70 and 110 of gestation, and US (n = 13), that were not shorn pre-partum. Gestation length, lambing duration, placental expulsion time, placental weight, number and weight of cotyledons, and placental efficiency (lamb weight/placental weight) were determined. At birth, body temperature, weight, morphometric measurements, ponderal index (lamb weight/lamb crown-rump length) and behaviour were recorded, with weight remeasured 72 hours later. Four male lambs per group were slaughtered immediately after parturition, and organ weight and perirenal brown fat weight and energy content recorded. Pre-partum shearing, regardless of timing, increased total dried placental weight per ewe. Pre-partum shearing at Day 70 of gestation increased the number and mean weight of the > 2 to ≤ 3-cm cotyledons, while pre-partum shearing at Day 110 of gestation increased only the weight of these cotyledons. At birth and at 72 hours, lambs from ewes shorn either at 70 days of gestation (birth: 5.5 (95% CI = 4.6-6.4) kg, p = 0.001; 72 hours: 6.4 (95% CI = 6.1-6.8) kg, p = 0.002) or at 110 days of gestation (birth: 5.4 (95% CI = 4.4-6.4) kg, p = 0.001; 72 hours: 6.5 (95% CI = 5.9-7.1) kg, p = 0.001) were heavier than lambs from unshorn ewes (birth: 4.0 (95% CI = 3.3-4.8) kg; 72 hours: 4.8 (95% CI = 3.5-6.1) kg). Lambs born to S70 and S110 ewes suckled sooner (31.5 (95% CI = 14.5-48.5) minutes, p = 0.001; and 39.3 (95% CI = 23.7-55.0) minutes, p = 0.001 respectively), than lambs born to the US group (70.3 (95% CI = 38.6-102.1) minutes). There was no evidence for an effect of pre-partum shearing on gestation length, parturition length, time of placental expulsion, placental efficiency, weight and energy of perirenal brown fat, and lamb temperature at birth. Shearing ewes pre-partum may lead to placental changes affecting lamb development and behaviour and associated with higher survival. The findings suggest pre-partum shearing may improve lamb survival, farm profitability and sustainability.

Dried distiller’s grains in the diets of feedlot lambs: implications for production, carcass characteristics and rumen morphometrics

Context The demand and production of renewable fuels are boosting the production of biofuels. Agricultural industries have been playing a role in the increase of ethanol production from corn and, consequently, their by-products. Dried distiller’s grain (DDG) is a by-product of corn ethanol and can be used as a source of protein and energy in the diet of feedlot lambs. Aims The objectives of this experiment were to evaluate the effects of including DDG in high-concentrate diets on performance, rumen morpho-histology, and carcass characteristics in feedlot lambs. Methods Forty-five Santa Inês × Dorper male lambs with an initial body weight of 21 ± 3.2 kg (mean ± s.d.) and 82 ± 12 days old (mean ± s.d.) were distributed in a randomised complete-block design (nine blocks and five treatments). The experimental diets contained 900 g/kg of concentrate and 100 g/kg of coastcross hay, and DDG was used in replacement of soybean meal and corn. Lambs were fed one of the following five diets for 112 days: control without DDG (0DDG), or diet with 150 (150DDG), 300 (300DDG), 450 (450DDG) and 600 (600DDG) g/kg DM of DDG. Key results The inclusion of DDG from 150 up to 600 g/kg DM in the diet of the lambs linearly decreased (P &lt; 0.01) dry-matter intake (DMI), net energy of maintenance intake, net energy of gain, average daily gain, final body weight and feed efficiency (P &lt; 0.01). The inclusion of DDG linearly decreased (P ≤ 0.04) hot carcass weight, cold carcass weight, hot carcass yield and cold carcass yield. For ruminal morpho-histology, there was a linear decrease in the area of papillae and absorptive surface area (P &lt; 0.01) Conclusions An increase in the DDG level from 150 to 600 g/kg DM in the diet of lambs negatively affected feedlot performance, with detrimental effects on carcass traits and the development of rumen papillae. The lambs showed low acceptance of DDG, even at the lowest level of dietary inclusion (150g/kg DM) as DMI was impaired. Implications DDG should be used with caution in diets for finishing lambs. Dietary inclusion of DDG up to 150 g/kg DM is recommended. Higher inclusions levels may significantly affect performance and carcass weight and yield.

The Potential of Three Vetch Species in Enhancing Feed Intake and Body Weight Gain of Growing Male Lambs

An experiment was intended to evaluate the potential of three vetch species in enhancing feed intake and body weight gain of growing male lambs and to investigate the difference among these three vetch species regarding their effect of supplementation on feed utilization and growth performance of growing male lambs. Twenty-four young male Arsi-Bale lambs of similar body weight were assigned to one of the four treatments in a randomized complete block design. The dietary treatments were 350 g of hay each of &amp;lt;i&amp;gt;Vicia sativa,&amp;lt;/i&amp;gt; &amp;lt;i&amp;gt;Vicia Villosa,&amp;lt;/i&amp;gt; and &amp;lt;i&amp;gt;Vicia narbonensis&amp;lt;/i&amp;gt; for T2, T3, and T4, and ad libitum fodder oat hay alone (T1). Weight measurements of the lambs were made every ten days during the ninety-day feeding trial. Compared to T1 and T3, T2&amp;apos;s total dry matter intake (1121.4 g/day) was substantially (P&amp;lt;0.05) greater. Lambs fed T2 diets showed significantly higher (P&amp;lt;0.001) crude protein intake (153.3 g/day) and average daily body weight increase (152.0 g/day). In conclusion, supplementation with Vicia sativa (T2) resulted in the highest feed intake and growth performance of lambs across all treatments. As a result, efforts should be undertaken to introduce and expand the production of this forage within the farming system.

Soybean oil, linoleic acid source, in lamb diets: carcass traits and meat quality.

We developed a study to determine the ideal level of inclusion of soybean oil (SBOil) in the diet without affecting the quantitative and qualitative parameters of the carcass and meat of lambs in a feedlot system; therefore, determining the ideal level of inclusion. Forty male lambs (Santa Inês breed) were used. The initial body weight and age averaged 34.88 ± 3.19kg and 5months, respectively. Experimental units (lambs) were randomly distributed in 5 different diets: inclusion levels of SBOil: 0, 30, 60, 90, and 120g/kg of dry matter (DM). The SOil inclusion reduced the DM intake (P < 0.001), Total digestible nutrients (P = 0.004), and crude protein (P < 0.001). Total weight gain (P < 0.001) decreased with the SBOil inclusion and subcutaneous fat thickness (P = 0.017) showed the same behaviour. The final body weight decreased by 42.9g/kgDM until the inclusion level of 30g/kgDM; from this level it was reduced by 145g/kgDM. The hot and cold carcass weights (P = 0.013) decreased by 36.6g/kgDM after including 30g/kgDM of SBOil. Meat physicochemical composition was not altered (P > 0.05). Lower meat tenderness values ​​were obtained at the levels of 60 and 90g/kgDM. The inclusion above 30g/kgDM decreased meat tenderness. It is concluded that soybean oil should be included up to 30g/kgDM in diets. It is important to note that with diets with 60% concentrate, SBOil levels greater than 30g/kgDM promote yield losses.

PSLBI-13 Characterizing the seminal microbiota in mature rams managed on divergent planes of nutrition, and in their male offspring

Abstract Increasing evidence suggests that the bovine semen harbors commensal microbiota, and it may be important in male fertility. However, much is unknown regarding the seminal microbiota, its evolution and factors shaping this community in sheep. The objective of this study was to evaluate whether managing the rams on divergent planes of nutrition can influence the seminal microbiota in mature rams and their male offspring. For this, Rambouillet rams (n = 24; 1.5 to 4 yr old) were randomly assigned to one of three groups: 1) a positive plane of nutrition [target 12% gain in their initial body weight (BW; POS, n = 8); 2) a maintenance [maintain the initial BW (MNT, n = 8)]; and 3) a negative [target a 12% reduction in BW (NEG; n = 8)] plane of nutrition over 84 d. The rams were individually housed and fed a common diet, and feed allocations were adjusted weekly. Following the 84-d feeding period, these rams were used to breed 240 mature Rambouillet ewes (1:10 ram:ewe ratio) over 28 d of breeding. After lambing, the male lambs were maintained on a similar diet for 124 d. Semen samples from the mature rams (F0 generation) were collected on d 28, 56, and 84, and semen samples from offspring rams (F1 generation) were collected at 330 d of age via electroejaculation. Genomic DNA was extracted from semen samples and the seminal microbiota characterized using 16S rRNA gene (V3-V4) sequencing. Several environmental and negative extraction controls were also sequenced to assess potential contaminants in these samples. Overall community structure of the seminal microbiota in F0 rams was not affected by the divergent planes of nutrition (PERMANOVA: P ≥ 0.05) or by sampling time (P &amp;gt; 0.05). Microbial richness (observed ASVs) was also not different (P &amp;gt; 0.05) between the three groups of F0 rams at any of the sampling time points; however, microbial diversity (P &amp;lt; 0.05) in the F0 rams was influenced by sire dietary treatment. Microbial community structure, richness and diversity did not differ among the POS, MNT and NEG F1 generation rams (P &amp;gt; 0.05). Actinobacteriota, Firmicutes, Bacteroidota, Proteobacteria and Fusobacteriota were the most abundant phyla. Only Bacteroidota abundance was significantly (P &amp;lt; 0.05) different between three F0 groups, with POS rams had greater (18.6%) of this phylum on d 28 as compared with MNT (2.1%) and NEG (5.1%). The predominant genera identified included Fastidiosipila, Corynebacterium, Trueperella, Arthrobacter, Dietzia, Bifidobacterium, Streptobacillus, Ornithinimicrobium, and Porphyromonas, and their relative abundance was not affected (P &amp;gt; 0.05) by the dietary treatment in F0 rams. Overall, rams managed on positive and negative planes of nutrition harbored similar seminal microbiota to control rams, and divergent nutrition also had no effect on the offspring ram seminal microbiota.

Immune, Oxidative, and Morphological Changes in the Livers of Tibetan Sheep after Feeding Resveratrol and β-Hydroxy-β-methyl Butyric Acid: A Transcriptome-Metabolome Integrative Analysis.

This study investigated the effects of dietary resveratrol (RES) and β-Hydroxy-β-methyl butyric acid (HMB) on immune, oxidative, and morphological changes in the livers of Tibetan sheep using transcriptomics and metabolomics. One hundred and twenty male Tibetan lambs of a similar initial weight (15.5 ± 0.14 kg) were randomly divided into four groups with thirty lambs per treatment: (1) H group (basal diet without RES or HMB); (2) H-RES group (1.5 g/day of RES); (3) H-HMB group (1250 mg/day of HMB); (4) H-RES-HMB group (1.5 g/day of RES and 1250 mg/day of HMB). The experiment was conducted for 100 days, including a pre-test period of 10 days and a formal period of 90 days. The results showed significantly increased concentrations of glutathione peroxidase, superoxide dismutase, and IgM in the H-RES-HMB group (p < 0.05), while the malondialdehyde levels were significantly decreased (p < 0.05). The glycolytic indices including creatinine kinase (CK), malate dehydrogenase (MDH), and succinate dehydrogenase (SDH) were significantly increased in the H-RES-HMB group compared with the others (p < 0.05). A histological analysis showed that the hepatic plate tissue in the H-RES-HMB group appeared normal with multiple cells. The transcriptomic analysis showed that the expression of genes associated with the calcium signaling pathway (MYLK2, CYSLTR2, ADCY1, HRH1, ATP2B2, NOS2, HRC, ITPR1, and CAMK2B) and the NF-κB signaling pathway (BCL2 and CARD14) in the H-RES-HMB group were upregulated. The key differential metabolites (d-pyroglutamic acid, DL-serine, DL-threonine, fumarate, and glyceric acid) were enriched in the pathways associated with D-amino acid metabolism, the citrate cycle (TCA cycle), and carbon metabolism. The combined transcriptomic and non-targeted metabolomic analyses showed the co-enrichment of differential genes (NOS2 and GLUD1) and metabolites (fumarate) in arginine biosynthesis-regulated glycolytic activity, whereas the differential genes (ME1, SCD5, FABP2, RXRG, and CPT1B) and metabolites (Leukotriene b4) co-enriched in the PPAR signaling pathway affected the immune response by regulating the PI3K/AKT and cGMP/PKG signaling. In conclusion, the dietary RES and HMB affected the hepatic antioxidant capacity, immune response, and glycolytic activity through modulating the transcriptome (BCL2, CAMK2B, ITPR1, and IL1R1) and metabolome (DL-serine, DL-threonine, fumaric acid, and glycolic acid).