Search Results (72)

Dietary supplementation under high ambient temperatures can be considered crucial for supporting immune responses in livestock. In the present paper, Rosmarinus officinalis essential oil (REO) alone and in combination with dried sugar beet pulp (REO + B) was included in the diet of lambs during the fattening period under heat stress conditions. Environmental conditions and physiological and growth parameters of lambs were monitored throughout the trial. Plasma samples were collected to evaluate cytokine secretion (IL-1β, IL-6, and IL-10). Notably, REO inclusion reduced rectal temperature and respiration rate while increasing pro-inflammatory cytokines (IL-1β and IL-6) at the same time, suggesting an enhanced immune response without compromising growth performance. Full article

The aims of the current study were to characterize the natural compounds of Salsola tragus via GC-MS and determine its effects as a forage source on lamb growth, in vitro rumen fermentation kinetics, carcass quality, cellular damage, and metabolomic meat interaction. Twenty-one Rambouillet lambs were randomly assigned to one of three experimental diets (seven lambs per treatment): (1) a control diet (W/o-Salsola) containing 300 g/Kg dry matter (DM) of sorghum stover; (2) a diet with a medium inclusion of Salsola tragus (15-Salsola), which contained 150 g/Kg DM of Salsola tragus and 150 g/Kg DM of sorghum stover; and (3) a diet comprising 300 g/Kg of Salsola tragus (30-Salsola). The results showed there were no differences (p > 0.05) in lamb growth performance during the fattening phase. The in vitro gas analysis demonstrated that the 30-Salsola treatment increased lag time h⁻¹ (p < 0.05) and reduced gas production (p = 0.03). The metabolomic analysis findings suggest that the treatments that included Salsola tragus significantly positively affect the metabolomic composition of meat (p < 0.05). The use of 15-Salsola as a source of forage is promising for feeding lambs during the fattening phase. Full article

This study evaluated the effects of dietary Rhodotorula yeast culture (RYC) supplementation on carcass traits, meat quality, antioxidant capacity, shelf life, and flavor substance in fattening lambs. Twenty-four three-month-old male Dorper × Han crossbred sheep (body weight: 36 ± 4 kg) were randomly assigned to four groups: R0 (basal diet), R10 (basal diet + 10 g RYC/day), R20 (basal diet + 20 g RYC/day), and R40 (basal diet + 40 g RYC/day). The experiment lasted 75 days. Compared to the control group, the R10, R20, and R40 groups exhibited significant reductions in shear force (p < 0.01), malondialdehyde levels (p < 0.01), and day-15 total volatile basic nitrogen values (p < 0.05), along with significant increases in glutathione peroxidase activity (p < 0.05) and total umami-taste amino acid content (p < 0.01). The R20 group also demonstrated significant increases in backfat thickness, muscle crude protein content, and total antioxidant capacity (p < 0.05). These results indicate that dietary supplementation with 20 g RYC improves physicochemical properties, antioxidant capacity, shelf life, and flavor compounds in fattening lambs. 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

Adequate management of replacement ewe lambs (F0) in dairy sheep farms during postnatal life may modify the germline cells, thus promoting transmission of intergenerational effects to the offspring (F1). To test this hypothesis, 18 newborn male lambs (F1), either born from methionine-supplemented ewe lambs (F0 ewe lambs being fed ad libitum with a milk replacer supplemented with 1 g methionine/kg DM) or not supplemented (F0 ewe lambs being fed ad libitum with the same milk replacer with no methionine added), were included in the present study. All the male F1 lambs were managed exactly in the same way along the whole lifespan in order to bring out the differences caused by methionine supplementation of F0 dams. Our data show that the methionine supplementation of dams (F0) during the suckling period did not promote significant (p > 0.05) changes on feed intake, growth rate, or feed efficiency of F1 male lambs during the fattening period. Moreover, the meat chemical composition (proximal, fatty acid profile, and volatile compounds) was similar for both groups (p > 0.05), but the meat of F1-MET lambs presented higher redness and hardness (p < 0.05) when compared to F1-CTRL lambs. The biochemical profile also highlighted significant (p < 0.05) differences in the serum creatinine and calcium content that may be at least partially related to the meat quality traits observed. Overall, all these results suggest that methionine supplementation of lambs (F0) during early postnatal life causes permanent changes in the offspring. This has positive effects, such as achieving a more attractive color of lamb meat (F1) for consumers, and negative effects, such as reduced meat tenderness. 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

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

The objective of this study was to evaluate the impact of dietary carob pulp (Cp, Ceratonia siliqua L.) and vitamin E (Vit E) on the quality and shelf-life of light lamb meat stored for a maximum of 15 days under modified atmosphere packaging (MAP). Forty-eight lambs (half females and half entire males, 25.3 ± 0.3 kg of body weight and 83 ± 5.8 days old) were randomly selected and slaughtered after an experimental fattening period with a 2 × 2 factorial design: 0 vs. 20% Cp and 40 vs. 300 IU of Vit E/kg of diet for 41 days. The carcass traits, fatty acid (FA) profile, antioxidant content, colour, lipid oxidation, and microbial count in the meat were evaluated. Scarce interactions between Cp and Vit E were observed on most of the variables studied. The dietary inclusion of Cp did not affect carcass traits (p > 0.05) but produced minor changes in the content of branched FA and reduced the α-tocopherol content in the meat (p < 0.05), while no impact was observed on discolouration or lipid oxidation (p > 0.05). High Vit E supplementation increased the yellowness of caudal fat and the α-tocopherol content, which limited discolouration and lipid oxidation (p < 0.05). Furthermore, the High Vit E diet (without Cp) controlled the psychrotrophic bacterial count after 15 days of storage. At slaughter, males were heavier than females but had lower carcass dressing (p < 0.05). The lambs’ sex had minor impacts on the quality and shelf-life of meat. This study demonstrated that there is no synergistic interaction between Cp and Vit E on lamb meat quality and shelf-life. Including 20% of Cp in lamb diets is feasible without impairing meat quality. Nevertheless, supplementation with 300 IU of Vit E/kg of feed is essential to extend the shelf-life of meat stored under MAP. Full article

The impact of macroalgae species on rumen function remains largely unexplored. This present study aimed to identify the biocompounds of the three types of marine macroalgae described: Macrocystis pyrifera (Brown), Ulva spp. (Lettuce), Mazzaella spp. (Red) and their effect on species-specific modulations of the rumen microbiome. The macroalgae were characterized using GC-MS. Twelve Rambouillet lambs were randomly assigned to one of four experimental diets (n = 3 per treatment): (a) control diet (CD); (b) CD + 5 g of Red algae; (c) CD + 5 g of Brown algae; and (d) CD + 5 g of Lettuce algae. After the lambs ended their fattening phase, they donated ruminal fluid for DNA extraction and 16S rRNA gene V3 amplicon sequencing. Results: The tagged 16S rRNA amplicon sequencing and statistical analysis revealed that the dominant ruminal bacteria shared by all four sample groups belonged to phyla Firmicutes and Bacteroidota. However, the relative abundance of these bacterial groups was markedly affected by diet composition. In animals fed with macroalgae, the fibrinolytic and cellulolytic bacteria Selenomonas was found in the highest abundance. The diversity in chemical composition among macroalgae species introduces a range of bioactive compounds, particularly VOCs like anethole, beta-himachalene, and 4-ethylphenol, which demonstrate antimicrobial and fermentation-modulating properties. Full article

The objective of the present study was to characterize the chestnut (Castanea sativa Mill.) tannin product, Farmatan Plus^® (Tanin Sevnica d.d., Sevnica, Slovenia), and to subsequently examine its effects on the blood metabolic parameters of fattening lambs, particularly in relation to their health status. Thirty lambs were randomly divided into three treatment groups: a control group without added tannin and two groups that received 9.46 g of the tannin product/kg of the diet dry matter (DM) and 18.87 g of the tannin product/kg of the diet DM. Metabolic parameters such as contents of total protein, globulin, urea, and liver enzymes (AST and GGT) were measured over a trial period of 60 days to evaluate the effects of tannin supplementation. This study represents the first in-depth characterization of Farmatan Plus^®, demonstrating its richness in bioactive compounds such as vescalin and castalagin. The results showed no significant adverse effects on lamb health, with all parameters remaining within normal physiological ranges (p > 0.05). These results support the safe inclusion of chestnut tannins in the diet of lambs and underline their potential as a functional feed additive that can positively influence the health and growth performance of ruminants. Full article

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. Full article

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. Full article

The study aimed to establish the dietary effects of black oat rich in polyphenols on the production traits, metabolic profile, antioxidant status, and carcass quality of fattening lambs, after weaning. In the BO group, in the feed mixture, common oats replaced the black oat compared to the CO group. The research comprehensively investigated production indicators, blood metabolic profile, antioxidant status, and lamb carcass quality. No significant differences were found in the fattening or slaughter characteristics of lamb carcasses, except for lower pH₁ values in BO lamb carcasses. Significant increases in RBC, HCT, and MCV levels as well as TP, ALB, and GLOB concentrations and GPx and SOD activities in the blood of BO lambs were found. The glucose and EOS content as well as the activity of the enzymes ALT and ALP were significantly lower in the blood of the BO group than in the CO group. In the liver, the DPPH activity was significantly higher in the BO lambs compared to the CO lambs. The observed changes in glucose, protein metabolism, and antioxidant status in the blood and tissues of lambs indicate that the use of polyphenol-rich black oats in the diet of lambs under stress conditions is justified. Full article

This experiment aimed to study the effects of tannin supplementation on growth performance, rumen fermentation characteristics, apparent digestibility and serum biochemistry, and antioxidant and immune indexes in fattening lambs. A total of 36 male Hu sheep lambs (body weight = 15.83 ± 0.48 kg and days of age = 55 ± 2 d) were fed a high-concentrate diet and randomly divided into one of three groups of 12 animals each: control with no tannin (CON) and tannin treatments (TA1, 3 g/d per lamb; TA2, 6 g/d per lamb). The feeding experiment lasted for 60 d. The results showed that the average daily gain and ruminal propionate content of lambs in the TA1 group were higher (p < 0.05) than those in the CON group. Lambs fed tannin had significantly increased (p < 0.05) microbial protein and decreased (p < 0.05) ammonia nitrogen concentrations in the rumen. In addition, the crude protein and neutral detergent fiber digestibility of the TA2 group were significantly decreased (p < 0.05) as compared with the TA1 and CON groups, respectively. The serum concentrations of triglyceride, immunoglobulin A, and catalase and the total antioxidant capacity were higher (p < 0.05) in the TA1 group that those in the CON group, whereas an opposite trend of urea nitrogen, interleukin-1β, and malondialdehyde was found between the two groups. Also, tannin supplementation increased (p < 0.05) Lactobacillus and decreased (p < 0.05) Salmonella counts in the feces of lambs. Taken together, tannin supplementation can improve the growth performance, immunity, and antioxidant ability of fattening lambs fed a high-concentrate diet. Full article

Extensive traditional livestock systems currently face various threats, leading to their disappearance. An example of these extensive livestock farming systems is the production of the Lojeña sheep breed in the Sierra de Loja (Granada, Spain), with a census of 24,511 ewes in 2021. The aim of this work is to calculate the carbon footprint (CF) of this local breed in this region. This study is based on data collected from 27 Lojeña sheep farms producing weaned lambs (≤14 kg, 25 farms), fattened lambs (≈25 kg, 7 farms), culled animals (24 farms) and greasy wool (27 farms). Most of these farms (78%) were organically (ORG) certified and seven were conventionally (CONV) managed. The analysed farms represent 93% of the total number of farms producing Lojeña sheep in the Sierra de Loja. The CF was calculated with a “cradle to farm gate” approach. The average C footprints were 27.5 ± 6.8 kg CO₂eq kg_LW⁻¹ for weaned lambs, 21.8 ± 8.5 kg CO₂eq kg_LW⁻¹ for fattened lambs, 4.1 ± 2.6 kg CO₂eq kg_LW⁻¹ for culled animals and 2.2 ± 0.6 kg CO₂eq kg⁻¹ for greasy wool, with a not statistically different average CF in ORG than in CONV farms. Enteric fermentation represents the main source of emissions (>60%) in all the products, and external feeding (including transport, and emissions from producing the feed) represents the second one (>10%). There was an inverse relationship between CF and productivity (lambs sold ewe⁻¹ year⁻¹), leading to lower footprints on those farms with the higher productivity. A direct relationship between CF and stocking rate (livestock units ha⁻¹) has been identified. Full article