Ensiling Sorghum with Urea, Aerobic Exposure and Effects on Intake, Digestibility, Ingestive Behaviour and Blood Parameters of Feedlot Lambs.

This study was carried out to evaluate the effect of ensiling sorghum silage with urea and amending the aerobic exposure nutrients intake and apparent digestibility, ingestive behaviour and blood serum metabolites of feedlot lambs. Forty uncastrated crossbred Dorper × Santa Inês lambs, aged 150 ± 15 days and with an initial body weight of 21.73 ± 2.40 kg, were used. Animals were assigned in a 2 × 3 factorial arrangement. Thus, six silage diets were produced with various urea addition levels (UA: 0 and 5 g/kg on a natural matter basis) and periods of aerobic exposure of silages (PAE: 0, 24 and 48 h). An effect was observed for nutrient intakes of dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fibre corrected for ash and protein (NDFap) and total digestive nutrients TDN (g/day) and for the total apparent digestibility of DM, OM and CP. There was an interaction effect between urea levels and aerobic exposure for ether extract (EE) and NDFap intakes (g/kg) and nonfibrous carbohydrate (NFC) digestibility (g/kg) (p = 0.012). The addition of 5 g/kg of urea to sorghum ensilage improved the digestibility parameters without changing dry matter intake and ingestive behaviour. The addition or not of urea does not change the blood parameters of the animals.

Whole Corn Germ as an Energy Source in the Feeding of Feedlot Lambs: Metabolic and Productive Performance.

The aim of this study was to evaluate the dietary inclusion (0, 30, 60, 90, and 120 g/kg DM) of whole corn germ (WCG), an energy source, on the metabolic and productive performance of feedlot lambs. To this end, two complementary experiments were carried out. In Experiment I, we tested the effects of WCG inclusion levels on the metabolism of 10 uncastrated Santa Inês male lambs, which were distributed into two 5 × 5 Latin squares design. Non-fibrous carbohydrates digestibility decreased (p = 0.01), whereas ether extract digestibility increased (p < 0.01) with the inclusion of WCG. Retained nitrogen did not change (p = 0.99) with the WCG inclusion. In Experiment II, we tested the effect of WCG inclusion levels on the production performance of 40 uncastrated Santa Inês male lambs, in a completely randomized design. There was a reduction in the intake of nutritional components (p < 0.05), except EE (p < 0.01), which increased with the increasing WCG levels. Production performance and blood parameters did not change. Based on the observed metabolism, performance, and feed efficiency, the use of WCG at up to 120 g/kg DM, in the total diet, is recommended as an alternative energy source for feedlot lambs.

Effects of Whole Corn Germ, A Source of Linoleic Acid, on Carcass Characteristics and Meat Quality of Feedlot Lambs.

The whole corn germ (WCG), due to its desirable nutritional characteristics, has been studied as feed for ruminants. This study aimed to evaluate the effects of WCG inclusion as a linoleic acid source in diets for feedlot lambs on carcass characteristics, physicochemical composition, sensory attributes, and fatty acid profile of the meat. Forty non-castrated, crossbreed Dorper x Santa Inês lambs were distributed in a completely randomized design to evaluate the inclusion levels (0, 30, 60, 90, and 120 g/kg dry matter (DM)) of whole corn germ (WCG) in the diet. The dietary inclusion of WCG did not influence (p > 0.05) the weight gain and carcass characteristics, with the exception of the subcutaneous fat thickness (p < 0.01), which was higher in animals fed diets with higher levels of WCG. Lightness (L *; p = 0.04), yellowness (b *; p < 0.01), shear force (p = 0.04), linoleic fatty acid concentrations (p = 0.03), and total polyunsaturated fatty acids (p = 0.04) had a quadratic increase due to WCG inclusion in the diets. The use of up to 120 g/kg DM of WCG in lamb diets does not affect the carcass characteristics, physicochemical composition, and sensory attributes of the meat. Despite this, the best polyunsaturated fatty acid profile in lambs' meat is obtained using 76.7 g/kg DM of WCG.

Correlation between production performance and feeding behavior of steers on pasture during the rainy-dry transition period.

The aim of this study was to evaluate the correlation between production performance and feeding behavior of steers reared on pasture during the rainy-dry transition period. Twenty-two ½ Holstein-Zebu crossbred steers at an average age of 10 months and with an average initial body weight of 234.5 ± 16.0 kg were distributed in a completely randomized design with two types of supplementation and eleven replications. Pearson's linear correlation analysis was performed between behavioral variables and weight gain and feed conversion. Correlation coefficients were tested by the t test. The time expended feeding at the trough was positively correlated (P < 0.05) with average daily gain (ADG) and with the number of periods of permanence at the trough. Bite rate and the number of bites per day were positively correlated (P < 0.05) with ADG and negatively (P < 0.05) with feed conversion, unlike the number of bites per swallow, which was negatively correlated (P < 0.05) with ADG. There was a positive correlation (P < 0.05) between feed efficiency in dry matter and neutral detergent fiber and ADG. Feeding behavior characteristics have little association with the production performance of cattle on pasture receiving mineral or energy-protein supplementation.

Evaluation of days of total collection and use of internal markers in nutritional trials with small ruminants.

Two experiments were conducted to evaluate the number of days required for total fecal collection and the viability of using the indigestible dry matter (iDM), indigestible neutral detergent fiber (iNDF), and indigestible acid detergent fiber (iADF) internal markers to determine the fecal excretion of dry matter (FEDM) and digestibility in nutritional trials with small ruminants. Eight sheep in the first experiment and eight goats in the second experiment were distributed into two 4 × 4 Latin square designs. There were no significant differences between days of total fecal collection for FEDM; digestibility of dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), neutral detergent fiber corrected for ash and protein (NDFap), and non-fibrous carbohydrates corrected for ash and protein (NFCap); and total digestible nutrients (TDN) in both species. The results suggest that only 1 day of total collection is sufficient to obtain the FEDM and the digestibility of the nutritional components in sheep and goats. The markers are efficient in determining fecal production and digestibility in these animal species.