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Simple Summary: Enhancing the energy density of lamb diets is a proven method to improve their productivity. While using carbohydrates for this purpose may seem intuitive, it can lead to undesirable shifts in ruminal metabolism, potentially triggering metabolic diseases. Hence, substituting carbohydrates with lipids is favored. Nevertheless, lipids, though effective, can also disrupt ruminal fermentation parameters. Among these lipids, soybean oil stands out for its positive impact on both beef and dairy cattle, leading to improved performance. In our study, we sought to assess the effects of soybean oil supplementation on performance, digestibility, feeding behaviour, and blood metabolites of feedlot lambs. Our findings indicate that the inclusion of soybean oil resulted in a linear reduction in nutrient intake, consequently lowering the average daily gain of the lambs. Additionally, soybean oil supplementation induced selective feeding behaviour among the lambs. Based on our observations, we recommend incorporating soybean oil into lamb diets at a maximum inclusion rate of 41 g/kg DM to optimize production parameters. The strategy implemented to adapt lambs to increasing levels of high-fat diet mitigated the detrimental effects of lipids on the rumen, with high-density energy intake being the constraining factor on performance. The objective of the current study was to evaluate the effects of soybean oil inclusion in diets on feeding behaviour, digestibility, performance, and blood metabolites of feedlot lambs. Forty non-castrated Santa Inês lambs with a mean age of 5 months and initial body weight of 34.88 ± 3.19 kg were used in a 40-day feeding trial. The lambs were distributed in five experimental diets with the inclusion of increasing soybean oil (SO) levels: 0, 30, 60, 90, and 120 g/kg DM. The SO inclusion promoted a linear reduction in DM intake (p < 0.001), crude protein (CP, p < 0.001), non-fibrous carbohydrates (NFC, p < 0.001), and total digestible nutrients (TDN, p = 0.004). There was an increasing quadratic effect on the intake of ether extract (EE; p = 0.002) and decreasing for neutral detergent fiber (p = 0.005). The soybean oil inclusion promoted the greater apparent digestibility of CP (p = 0.016), EE (p = 0.005), NDFom (p < 0.001), and TDN (p < 0.001); on the other hand, the apparent digestibility of NFC (p = 0.005) was decreased. The average daily gain decreased (p < 0.001) with SO inclusion. The SO inclusion increased feeding time (p = 0.004), reduced the efficiency of DM rumination (p = 0.001), and reduced the concentration of blood N-ureic (p < 0.001). Considering the productive parameters, SO can be included in diets and it is recommended that we include SO of up to 41 g/kg DM in diets for fattening lambs as the ideal maximum level. The strategy implemented to adapt lambs to increasing levels of high-fat diet mitigated the detrimental effects of lipids on the rumen, with high-density energy intake being the constraining factor on performance. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the productive potential, chemical composition, and fermentation profile of 24 genotypes of forage sorghum after ensiling. For this agronomic evaluation, a completely randomized block design with six replicates and twenty-four treatments was employed. Genotype 5 had the highest dry matter (DM) yield of 22.24 t/ha. The plant DM content ranged (p < 0.001) from 271.8 g/kg of fresh matter (FM) in genotype 9 to 330.0 g/kg FM in genotype 3, averaging 302.9 g/kg FM. The crude protein and non-fibrous carbohydrates differed significantly (p < 0.001) in the evaluated silages, with mean values of 61.0 and 275.3 g/kg DM, respectively. The pH of the sorghum silages also differed (p < 0.001), despite having an average of 3.94, with values ranging from 3.68 to 4.27. No changes were observed (p > 0.05) for the dry matter recovery of the sorghum genotype silages, which averaged at 853.9 g/kg FM. In the present study, genotype 5 resulted in being the most recommended genotype because it demonstrated a higher yield and higher nutritional value in both its fresh form and its ensiled form; had the lowest losses; and showed an ideal dry matter recovery after ensiling of 880 g/kg. [ABSTRACT FROM AUTHOR]

Context: The use of alternative sources in ruminant feeding features advantages such as diminished dependence on traditional cereals that can be used for human consumption or monogastric animals. Aims: This study was conducted to examine nutrient intake, apparent digestibility, mean growth rate, nitrogen balance, and microbial protein synthesis in lambs fed diets containing different energy sources in the concentrate. Methods: The experiment involved five uncastrated Santa Inês lambs, with an initial BW of 22.85 ± 1.0 kg, which were allocated individual metabolic cages and randomly assigned to one of the following five experimental treatments: maize (MA), wheat bran (WB), sorghum (SO), mesquite pod meal (MP) and peach palm meal (PP) in a 5 × 5 Latin square design, with five replicates each. Diets were isoenergetic with a roughage:concentrate ratio of 60:40. Key results: The energy sources in the concentrate influenced (P < 0.0001) the intakes of DM and nutritional components. The apparent digestibility coefficients of the ether extract and NDFap were significantly (P < 0.05) different between WB and the other diets. The different energy sources in the concentrate (MA, WB, SO and MP) increased (P < 0.0001) the mean growth rate of the lambs. The diet containing PP as an energy source provided a smaller (P = 0.0002) N intake than that from any other diet, and the PP diet resulted in a negative N balance (P = 0.0200). Lambs fed with diets containing MP (80.38 g day−1) as an energy source showed a larger (P = 0.0007) microbial protein synthesis than did those fed with PP (24.47 g day−1). Conclusions: Wheat bran, sorghum, and mesquite pod meal can completely replace maize for lambs fed diets based on 270 g kg−1 of maize. Implications: A variety of unusual feed ingredients facilitates the raising of lambs in various regions, with ingredients being local and of the lowest cost, promoting benefits to sheep producers. The raising of sheep is performed mostly exclusively on pasture; however, these rearing systems are subject to irregular availability of forage, and, consequently, reduction of the herd, and irregular supply of meat products. Thus, in an attempt to resolve this, it is necessary to adopt nutritional tools that are able to shorten the production cycle. Wheat bran, sorghum and mesquite pod meal can completely replace maize in the concentrate in the diets for feedlot lambs. [ABSTRACT FROM AUTHOR]

The objective of the current study was to evaluate the effects of soybean oil inclusion in diets on feeding behaviour, digestibility, performance, and blood metabolites of feedlot lambs. Forty non-castrated Santa Inês lambs with a mean age of 5 months and initial body weight of 34.88 ± 3.19 kg were used in a 40-day feeding trial. The lambs were distributed in five experimental diets with the inclusion of increasing soybean oil (SO) levels: 0, 30, 60, 90, and 120 g/kg DM. The SO inclusion promoted a linear reduction in DM intake ( p < 0.001), crude protein (CP, p < 0.001), non-fibrous carbohydrates (NFC, p < 0.001), and total digestible nutrients (TDN, p = 0.004). There was an increasing quadratic effect on the intake of ether extract (EE; p = 0.002) and decreasing for neutral detergent fiber ( p = 0.005). The soybean oil inclusion promoted the greater apparent digestibility of CP ( p = 0.016), EE ( p = 0.005), NDFom ( p < 0.001), and TDN ( p < 0.001); on the other hand, the apparent digestibility of NFC ( p = 0.005) was decreased. The average daily gain decreased ( p < 0.001) with SO inclusion. The SO inclusion increased feeding time ( p = 0.004), reduced the efficiency of DM rumination ( p = 0.001), and reduced the concentration of blood N-ureic ( p < 0.001). Considering the productive parameters, SO can be included in diets and it is recommended that we include SO of up to 41 g/kg DM in diets for fattening lambs as the ideal maximum level. The strategy implemented to adapt lambs to increasing levels of high-fat diet mitigated the detrimental effects of lipids on the rumen, with high-density energy intake being the constraining factor on performance.