Search Results (138)

The present study aimed to determine whether enriching the finishing ration of lambs with incremental doses of a protected fatty acid (FA) blend would result in noticeable differences in the eating experience of the resulting meat. Three isonitrogenous diets containing 0, 50, or 100 g day⁻¹ of the FA mixture were formulated, and the lambs were fed these diets until slaughter under otherwise identical management conditions. After postmortem aging, boneless loin samples from each treatment were submitted to a descriptive sensory evaluation by a rigorously trained panel that followed international guidelines. Multivariate techniques—principal component analysis combined with hierarchical clustering—were applied to integrate the panel’s quantitative scores and visualize how the treatments segregated in sensory space. The lamb meat presented a level of acceptance dependent on the proportion of fatty acids. In general, this study suggests that adding an extra 50 or 100 g of fat supplement to a lamb’s diet towards the end of its growth can significantly improve the enjoyment consumers get from eating the meat. Sensory analysis of lamb meat enriched with fatty acids indicated that the most important attributes determining the acceptance of lamb meat were color, flavor, odor, and toughness. Consequently, it can be recommended that dietary fatty acids be strategically increased during the finishing phase as a practical approach to enhancing the sensory appeal of sheep meat without compromising panel consensus. Full article

The increasing adoption of digital technologies in the agriculture sector has significantly contributed to optimizing on-farm routines, especially in data-driven decision-making. This study aimed to develop an application to determine the slaughter point of lambs by predicting subcutaneous fat thickness (SFT) using pre-slaughter parameters such as body weight (BW), body condition score (BCS), and skinfold measurements at the brisket (BST), lumbar (LST), and tail base (TST), obtained using an adipometer. A total of 45 Pantaneiros lambs were evaluated, finished in feedlot, and slaughtered at different body weights. Each pre-slaughter weight class showed a distinct carcass pattern when all parameters were included in the model. Exploratory analysis revealed statistical significance for all variables (p < 0.001). BW and LST were selected to construct the predictive equation (R² = 55.44%). The regression equations were integrated into the developed application, allowing for in-field estimation of SFT based on simple measurements. Compared to conventional techniques such as ultrasound or visual scoring, this tool offers advantages in portability, objectivity, and immediate decision-making support. In conclusion, combining accessible technologies (e.g., adipometer) with traditional variables (e.g., body weight), represents an effective alternative for production systems aimed at optimizing and enhancing the value of lamb carcasses. Full article

The aims of the present study were to analyze the taxonomic profile and to evaluate the functional effects of sheep FF cultivable microbiota on prepubertal lamb oocytes PLOs developmental potential. Ovarian FFs were recovered from slaughtered adult sheep via the aspiration of developing follicles and used for microbiota propagation. Bacterial pellets underwent 16S rRNA gene sequencing and targeted culturomics, whereas cell-free supernatants were used as supplements for the in vitro maturation (IVM) of slaughtered PLOs. For the first time, bacteria presence in adult sheep FF was detected, with the first report of Streptococcus infantarius subsp. infantarius (as a species) and Burkholderia cepacia (as a genus and species) in either animal or human FF. The short- and long-term effects of bacterial metabolites on PLO maturation and embryonic development were demonstrated. As short-term effects, the addition of FF microbiota metabolites did not affect the oocyte nuclear maturation and mitochondria distribution pattern, except in one of the examined supernatants, which reduced all quantitative bioenergetic/oxidative parameters. As long-term effects, one of them reduced the total cleavage rate after in vitro embryo culture (IVC). In conclusion, microbiota/bacteria are present in adult sheep FF and may influence reproductive outcomes in vitro. Future studies may reveal the beneficial in vitro effects using the microbiome from preovulatory follicles. Full article

Glycerol can effectively replace corn as an energy source in lamb diets without negatively impacting productive performance. This study evaluated the effects of substituting ground corn with different glycerol levels on the productive performance, ruminal fermentation, carcass characteristics, and meat quality at 24 h, 7, 14, and 21 d post-slaughter. A total of 40 male Suffolk × Hampshire crossbred lambs (25 ± 5 kg live weight) were used in a completely randomized design with four treatment groups (n = 10 each): 0% glycerol (GLY₀), 5% glycerol (GLY0₅), 10% glycerol (GLY₁₀), and 15% glycerol (GLY₁₅). Including glycerol in the diet did not affect growth performance (p > 0.05). However, it did lead to an increase (p < 0.05) in the concentrations of NH₃-N and the proportions of propionic and butyric acids, while the acetic acid levels decreased (p < 0.05). The backfat thickness, loin eye area (LEA), and carcass yield were not significantly affected (p > 0.05) by the addition of glycerol. Additionally, pH and color were also unaffected (p > 0.05), although the water-holding capacity showed a decrease (p < 0.05) over the shelf life of the meat. The chemical composition of the meat remained similar across all treatments, time points, and interactions (p > 0.05). In contrast, the protein content was significantly affected (p < 0.05) by the glycerol inclusion, time, and interactions between treatment and time. The results indicate that substituting up to 15% of ground corn with glycerol in lamb diets does not negatively impact productive performance, backfat thickness, LEA, carcass traits, or meat quality during shelf life. Throughout the shelf life, the crude protein concentrations and water-holding capacity decreased, while the propionic acid and NH₃-N concentrations increased. Full article

Leonardite (LEO), a microbial derived product rich in humic and fulvic acids, has been tested, due to its beneficial properties for health and well-being, as a feed additive, mainly in non-ruminant species. Although there are some reports of LEO supplementation in ruminants fed with high-to medium-forage based diets, there is no information available of the potential effects of LEO in ruminants fed, under sub-tropical climate conditions, with high-energy diets during long-term fattening. For this reason, the objective of the present experiment was to evaluate the effects of LEO levels inclusion in diets for feedlot lambs finished over a long-term period. For this reason, 48 Pelibuey × Katahdin lambs (initial weight = 20.09 ± 3.55 kg) were fed with a high-energy diet (88:12 concentrate to forage ratio) supplemented with LEO (with a minimum of 75% total humic acids) for 130 days as follows: (1) diet without LEO, (2) diet supplemented with 0.20% LEO, (3) diet supplemented with 0.40% LEO, and (4) diet supplemented with 0.60% LEO. For each treatment, Leonardite was incorporated with the mineral premix. Lambs were blocked by weight and housed in 24 pens (2 lambs/pen). Treatment effects were contrasted by orthogonal polynomials. The average climatic conditions that occurred during the experimental period were 31.6 ± 2.4 °C ambient temperature and 42.2 ± 8.1% relative humidity (RH). Those values of ambient temperature and RH represent a temperature humidity index (THI) of 79.07; thus, lambs were finished under high heat load conditions. The inclusion of LEO in diet did not affect dry matter intake (p ≥ 0.25) and average daily gain (p ≥ 0.21); therefore, feed to gain ratio was not affected (p ≥ 0.18). The observed to expected dietary net energy averaged 0.96 and was not affected by LEO inclusion (p ≥ 0.26). The lower efficiency (−4%) of dietary energy utilization is an expected response given the climatic conditions of high ambient heat load presented during fattening. Lambs that were slaughtered at an average weight of 49.15 ± 6.00 kg did not show differences on the variables measured for carcass traits (p ≥ 0.16), shoulder tissue composition (p ≥ 0.59), nor in visceral mass (p ≥ 0.46) by inclusion of LEO. Under the climatic conditions in which this experiment was carried out, LEO supplementation up to 0.60% in diet (equivalent to 0.45% of humic substances) did not did not help to alleviate the extra-energy expenditure used to dissipate the excessive heat and did not change the gained tissue composition of the lambs that were fed with high-energy diets during long-term period under sub-tropical climate conditions. Full article

In this study, we aim to analyze whether supplementation with cactus has the potential to minimize the testicular damage caused by heat stress, assess which of the three cactuses would have the best potential, and suggest a possible pathway (oxidative or hormonal) for the action of cactus on the testicular parameter alterations caused by heat stress. Thirty-two male lambs, of the Santa Inês type, not castrated, approximately six months old, and averaging 21.0 ± 2.0 kg body weight, were divided into four groups, as follows: G1, which was fed an elephant grass hay diet (control); G2, with a diet with partial replacement using small cactus forage (Opuntia cochenillifera) (SMALL); G3, which was fed Mexican elephant ear (Opuntia stricta Haw) (MEE); and G4, which was fed IPA Sertania (Nopalea cochenillifera Salm Dyck) (IPA) for 63 days. After slaughter, blood and testicles were removed. The right testicles were fixed for histological analyses, and the left testicles were stored in the freezer for oxidative stress analyses. Serum testosterone, T3, and T4 levels were analyzed. The body weight of animals treated with cactus forage was higher than in the control group. However, the gonadosomatic index did not differ among experimental groups. Heat stress triggered the degradation of testis tissue in all experimental groups. The testicular degeneration process was characterized by tubular atrophy, reduction in germ epithelium height, germ cell vacuolization and necrosis, Sertoli cell vacuolization, germ cell scaling of the tubular fire, and increased intertubular space. The three different cactus forages used in this study had different weaknesses regarding their antioxidant defenses, hormonal levels, and histopathology. However, it is important to highlight that the IPA group had lower qualitative changes in the intertubular areas than the other experimental groups. The testosterone level increased in MEE (Opuntia stricta) and IPA groups, while T3 and T4 increased in SMALL (Opuntia cochenillifera) and IPA groups. The malondialdehyde, an important marker of lipid peroxidation, was reduced only in the IPA group. The testosterone level increased in MEE and IPA groups, while T3 and T4 increased in SMALL and IPA groups. In conclusion, heat stress triggers several histopathologies in testis tissue, and IPA cactus (Nopalea cochenillifera) was the most appropriate supplementation for reducing the damages, compared with an elephant grass hay diet or small cactus forage and Mexican elephant ear supplementation. Full article

Through an integrated multi-omics analysis of rumen microbial communities, muscle transcriptomes, metabolic profiles, and liver metabolic profiles, this study systematically compared high- and low-performing lambs to elucidate their divergent effects on meat quality attributes and growth development. A total of 100 male lambs with similar birth weight (3.07 ± 0.06 kg) were selected within 72 h. All test lambs were synchronized weaning at 45 days of age and uniformly fed the same diet (total mixed ration) in the same pen until 180 days of age, with ad libitum access to food and water throughout this period. Subsequently, the eight lambs with the highest (HADG) and lowest (LADG) average daily gains were slaughtered for performance evaluation and multi-omics analysis. This study found that HADG lambs increased body weight, muscle fiber diameter, eye muscle area, improved amino acid (histidine, arginine, valine, isoleucine, essential amino acid/total amino acid, and essential amino acid/nonessential amino acid), and fatty acid (linoleic acid, behenic acid, and arachidonic acid) composition enhanced rumen enzymes (pepsase, lipase, xylanase, amylase, and carboxymethyl cellulose) and promoted efficient fermentation (p < 0.05). Analysis of microbial populations indicated a notable increase in Prevotella levels within the rumen of HADG lambs. Furthermore, the rumen markers Schwartzia and Streptococcus exhibited significant correlations with differential meat quality traits. Analysis of the muscle transcriptome indicated a significant correlation between the turquoise module and host phenotypes, particularly body weight. Additionally, muscle metabolism is primarily concentrated within the black module; however, it exhibits a significant correlation with the host body phenotype in the yellow module (p < 0.05). Moreover, liver metabolites, rumen microbes, host phenotype, and muscle transcripts were significantly correlated (p < 0.05). In conclusion, the interactions among rumen microbes, muscle, and liver in lambs promote rumen fermentation, which in turn regulate muscle transcriptional activity and modify metabolic profiles in both the liver and muscle. Moreover, PCK1, SPP1, FGF7, NR4A1, DUSP5, GADD45B, etc., can be candidate genes for muscle growth and development. This finding provides a theoretical basis for further exploiting the production potential of Hu lambs. Full article

Consumers are increasingly demanding higher-quality mutton. Crossbreeding has been recognized as an effective means to improve meat quality. However, the phenomenon underlying these molecular system mechanisms remains largely unidentified. In this study, 48 male lambs aged 3 months were selected, including ♂ Hu sheep × ♀ Hu (HH, n = 16), ♂ Polled Dorset × ♀ Hu sheep F₁ hybrid lambs (DH, n = 16), and ♂ Southdown × ♀ Hu sheep (SH, n = 16) F₁ hybrid lambs, and raised in a single pen under the same nutritional and management conditions for 95 days. Then, seven sheep close to the average weight of the group were selected and fasted for 12 h prior to slaughter. By comparing the muscle fiber characteristics of the Longissimus dorsi of the three groups of sheep, and through transcriptomic and metabolomic analyses, we revealed molecular differences in the meat quality of Hu sheep crossbred with different parent breeds. The results of this study showed that muscle fiber diameter and cross-sectional area were significantly greater in the DH group than in the HH group, and collagen fiber content in the DH group was also significantly higher than in the HH group (p < 0.05). A total of 163 differential genes and 823 differential metabolites were identified in the three groups, most of which were related to muscle development and lipid metabolism. These included the AMPK signaling pathway, the PI3K-Akt signaling pathway, glycerophospholipid metabolism, and the related genes EFHB, PER3, and PPARGC1A. The results of this study offer valuable insights into the molecular mechanisms underlying the impact of crossbreeding on meat quality and provide a theoretical foundation for sheep crossbreed production. Full article

New therapeutic molecules for farm animals are needed to address worldwide problems in the food industry, like the rise of resistance among ruminant parasites and pathogenic microbes. Since in vivo testing would involve an excessive number of animals, with consequent ethical and economic issues, the generation of sheep intestinal organoids represents a promising close-to-reality in vitro model for veterinary drug development; however, the characterization and application of such organoids remain limited. In this study, ovine intestinal organoids were generated from adult LGR5+ stem cells from the intestinal crypts of freshly slaughtered lambs, and developed in an in vitro culture system. Morphological analysis via brightfield microscopy and immunocytochemical staining revealed a pseudostratified epithelium with multiple cell types, and distinct apical–basal polarity, while RNA sequencing validated the preservation of the physiological characteristics of the original organ. The development and characterization of a robust and reproducible protocol for culturing sheep duodenum intestinal organoids in a high-throughput screening (HTS) compatible format demonstrated reliability in HTS applications, with Z’-factor tests indicating robust assay performance. Dose–response studies using pre-identified compounds showed comparable pharmacodynamic profiles between mouse and sheep organoids. These findings establish sheep intestinal organoids as an innovative tool for veterinary pharmacology and toxicology, offering a cost-effective and sustainable platform to address challenges such as drug resistance and improve livestock health. Full article

To address the bottleneck in meat production efficiency within China’s mutton sheep industry, this study established a two-generation crossbreeding program between WHS rams and STH ewes. Hybrid offspring (F1 and BC1) were evaluated for growth performance, slaughter traits, meat quality, and reproductive performance. The F1 generation exhibited significant improvements over STH in 6-month body weight (52.3 kg, +27.3%), dressing percentage (56.1%, +6.3%), and feed efficiency ratio (FER) of 4.6 (p < 0.05). The BC1 generation shows a mixed state of paternal and maternal characteristics and further enhanced these traits, achieving a 6-month body weight of 55.2 kg (+5.4% vs. F1), a dressing percentage of 58.3%, and an optimized gain-to-feed ratio (G:F) of 4.2 (−8.7%). Meat quality parameters, including shear force (32.5 N vs. 41.6 N in F1 vs. STH) and intramuscular fat content (4.5% vs. 3.8% in F1 vs. STH), demonstrated superior tenderness and marbling. Despite a decline in lambing rate (F1: 178%; BC1: 142%), the hybrids combined the dam’s adaptability with the sire’s meat traits, forming a novel germplasm for sustainable mutton production. This study provides a replicable model for balancing genetic improvement and ecological sustainability in central China. Full article

Supplemental zinc in fattening lambs improves their health, performance, and meat quality. However, the Zn effect on grazing animals combined with different levels of concentrate should be known unknown. The objective was to evaluate the Zn-organic effect in the diet of grazing lambs supplemented with two levels of concentrate on growth, dry matter (DM) intake, carcass traits, body composition, meat quality, and fatty acid profile in Longissimus dorsi muscle. Twenty-eight lambs were used in a factorial arrangement of two levels of concentrate (C) feed intake (C-0.75 and C-1.5% of live weight) and two Zn-Met levels (0 and 80 ppm Zn kg⁻¹ DM) on the grazing of Lolium perenne L. Digestibility and dry matter intake, weight gain, and productive performance were measured. At the end of the fattening period (90 d), the lambs were slaughtered and the carcass traits, body composition, instrumental quality, and lipid profile of meat were evaluated. The effect of treatment (T), measurement period (P), and T × P interaction was observed (p < 0.05) for dry matter intake (DMI). For the final live weight (FLW) and daily weight gain (DWG), there was an effect (p < 0.05) of T and P, with Zn-80 ppm + C-1.5% treatment being greater. The live weight at slaughter (LWS) and leg length (LL) showed an effect (p < 0.05) of C × Zn. Zn-80 ppm + C-1.5% treatment was higher in the kidney fat, empty body weight, carcass fat, fat and retained energy but lower in protein content (p < 0.05). The physicochemical characteristics and fatty acid content of meat were not affected (p > 0.05). It can be concluded that the concentrated-organic zinc synergy in grazing lambs improved the performance, weight gain, and body composition, which resulted in heavier carcasses with greater amounts of fat, protein, and energy deposited. Furthermore, the physical and chemical meat traits were not affected, but the n-3 fatty acid content and n-3/n-6 ratio in Longissimus dorsi was affected by the Zn level supplemented. Full article

The effects of incorporating yeast culture (YC) into pelleted feeds on sheep production and the potential impact on rumen microbial populations, microbial metabolism, and fermentation have not been extensively studied. This study aimed to evaluate the effect of YC on growth performance, rumen tissue development, rumen fermentation, and rumen microflora in sheep and to explore the potential microbial mechanisms involved. Fifty healthy 3-month-old male lambs of small-tailed Han sheep, with an average weight of 28.44 ± 0.63 kg, were randomly divided into five groups: control (0% YC), 3% YC, 6% YC, 9% YC, and 12% YC. The pre-feeding period lasted for 15 days, followed by an official feeding period of 60 days. On the last day of the formal feeding period, six lambs that exhibited the best growth performance were randomly selected from the control group and the 9% YC group. These sheep were slaughtered, then the rumen epithelial tissue and rumen contents were collected for the measurement of rumen fermentation, microbial populations, and metabolites. Compared to the control group, the YC-treated groups showed higher daily and final body weight gains, as well as increased levels of propionic acid, butyric acid, and total volatile fatty acids (p < 0.05). YC supplementation also enhanced rumen papilla length and width (p < 0.05). Additionally, YC increased the relative abundance of certain microbial species (p < 0.05). These results suggest that supplementing 9% YC in pelleted diets for small-tailed Han sheep may enhance growth performance and improve the rumen environment. Full article

In this study, we examined the effect of xylooligosaccharide (XOS) supplementation on the growth performance, carcass characteristics, and meat quality of Hu lambs. In total, 60 Hu lambs (two months old and weighing 17.32 ± 0.81 kg) were randomly assigned to four treatment groups, each with three replicates and five lambs per replicate. The lambs were fed basal diets supplemented with 0, 1.5, 3, or 4.5 g/kg XOSs in a basal diet for 60 days, with the groups designated XOS0%, XOS1.5%, XOS3%, and XOS4.5%, respectively. The results revealed, compared to theXOS0% group, the XOS3% group presented a lower F:G during 31 to 45 d (p = 0.06). By the 60th day, the body length indices of groups XOS3% and XOS4.5% increased compared to the XOS0% group, with a significant increase observed in group XOS4.5% (p < 0.05). Additionally, the GR values of the XOS1.5%, XOS3%, and XOS4.5% groups increased significantly, and the rumen fluid pH values of the XOS3% and XOS4.5% groups increased significantly (p < 0.01). The crude fat content in the XOS1.5% and XOS4.5% groups were significantly lower (p < 0.05). The hardness, adhesiveness, elasticity, cohesiveness, and chewiness of the mutton in the XOS1.5%, XOS3%, and XOS4.5% groups were increased, although the differences were not statistically significant (p > 0.05). Correlation analysis indicates that there is a significant correlation between growth performance, carcass traits, and meat quality (p < 0.05). The factors influencing meat quality originate from the growth period and the slaughtering phase, which can be attributed to the effects of xylooligosaccharides. In conclusion, XOS had positive effects on the growth performance, carcass characteristics, and meat quality of Hu lambs. The comprehensive effect of group XOS3% was best. Considering the production cost, the 3 g/kg XOSs is identified as the optimal supplementation level for sheep. Full article

The aim of this study was to evaluate the effect of sunflower cake from high-oleic seeds on performance, carcass characteristics, meat quality, and intramuscular fatty acid composition of finishing lambs. Thirty-six crossbred ewe lambs were assigned to four treatments (nine lambs/treatment) in a completely randomized design: 0 (control), 150, 300 and 450 g/kg DM of high-oleic sunflower cake. The lambs were weighed weekly and slaughtered with 42.3 ± 0.18 kg body weight and 270 ± 10.8 days of old. The inclusion of sunflower cake did not affect weight gain, dry matter intake and metabolizable energy intake (p > 0.05). There was an increase in neutral detergent fiber and EE intake (p < 0.01) with the inclusion of sunflower cake in the diet of the lambs. The inclusion of sunflower cake reduced hot and cold carcass yields (p < 0.01). Intramuscular fat content, L*, oleic acid, rumenic acid and EPA fatty acids linearly increased (p < 0.01) with the inclusion of high-oleic sunflower cake. The inclusion of high-oleic sunflower cake reduced saturated fatty acids (p < 0.01), except stearic acid, which linearly increased (p < 0.01). Up to 450 g/kg DM of high-oleic sunflower cake in the diet of lambs did not affect animal performance while providing a higher deposition of fat with better fatty acid composition for human consumption. Full article

Worldwide, there are reports indicating that sheep raised in insular systems spontaneously consume seaweed. In the southern hemisphere, there exists Durvillaea antarctica, a brown seaweed that possesses minerals and fatty acids that could improve some aspects of sheep production and meat quality, respectively. However, the consumption of this algae in lambs has been scarcely studied. The objective of this study was to evaluate the effects of dietary inclusion of Durvillaea antarctica meal on the growth performance, blood profile, and meat quality of fattening lambs. Thirty Araucana Creole lambs were housed and allocated to three pens. One pen served as a control, while the remaining two were supplemented with diets containing 5% and 10% Durvillaea antarctica meal. After 9 weeks, the animals were slaughtered. The dietary treatments did not significantly affect body weight and blood biochemical parameters. However, changes were observed in meat quality traits, including increased redness and reduced luminosity in the loin for the high inclusion treatment, in addition to slight alterations in pH and lower lipid oxidation in lambs’ meat fed Durvillaea antarctica. Furthermore, the meat from lambs supplemented with Durvillaea antarctica exhibited increased levels of linoleic acid and arachidonic acid, along with higher monounsaturated fatty acid content and a reduced omega-3/omega-6 ratio. This study shows that Durvillaea antarctica can be used to feed lambs without impairing growth or production parameters, which has been little studied. It is possible that this brown seaweed could be considered a natural additive to improve the quality and nutritional value of lamb meat. The effect of this seaweed on other ruminant models could be addressed in future studies. Full article