This study evaluated the performance, body water balance, ingestive behavior and blood metabolites in goats fed with cactus pear silage subjected to an intermittent water supply. Thirty-six goats were distributed in a randomized block design arranged as a 3 × 3 factorial with cactus pear silage in the goats’ diet (on a 0%, 21% and 42% dry matter-DM basis) and water offer frequency (ad libitum, and 24 and 48 h water restrictions). There was an interaction only between the cactus pear silage level and water offerings for drinking water. Goats fed 42% cactus pear silage had greater intake of non-fibrous carbohydrates, energy, Ca, Mg and Na minerals, water intake, urinary water excretion, body water retention and nutrient digestibility. Cactus pear silage inclusion up to a 42% rate reduced eating and ruminating time and increased the time spent idling as well as the eating and the ruminating efficiency rate. Water restriction at 48 h reduced drinking water intake. Performance and blood metabolites were not affected by cactus silage inclusion or water offering. Cactus pear silage inclusion at up to 42% for goats is recommended during periods of water shortage in semiarid and arid regions because it improves eating, the ruminating efficiency rate, and body water retention; cactus pear silage inclusion at this rate reduces water consumption and it does not affect the performance or health of the animals.

In ruminant feeding, mechanisms for controlling the rate of ammonia release in the rumen are important for increasing the efficiency of transforming dietary nitrogen into microbial protein. Three microencapsulated formulations, with increased urea concentrations of 10 (MPec1), 20 (MPec2) and 30% (MPec3) from the w/w, based on the mass of citrus pectin solution, employ the external ionic gelation/extrusion technique. The properties of microencapsulated urea were examined as a completely randomized design with 5 treatments each with 10 replicates for evaluation, and the ratios of dietary to free urea were compared using 5 fistulated male Santa Ines sheep in a Latin 5 × 5 square design. The degradation kinetics showed that the rate of controlled release from the microencapsulated systems was significantly reduced compared with that of free urea (p < 0.05). The population density of ruminal protozoa increased when sheep received the microencapsulated urea (p < 0.05). The disappearance of dry matter and crude protein reached a degradation plateau during the first minutes for the MPec1 and MPec2 systems and was slower for MPec3. The MPec1 and MPec2 systems presented higher (p < 0.05) blood serum concentrations of albumin, urea nitrogen (BUN), creatinine and total cholesterol and did not affect (p > 0.05) the other blood metabolites. The MPec2 systems are recommended because they consist of microspheres with more (p < 0.05) controlled core release, delaying the peak of urea released in the rumen and BUN without affecting (p < 0.05) ruminal pH and temperature. Microencapsulation with calcium pectinate provided better utilization of urea, reducing the risk of ruminant intoxication.

Lipid supplementation through vegetable oils in diets for ruminants can be a nutritional strategy to increase energy density, manipulate ruminal fermentation and change the physicochemical composition and sensorial properties of meat. This study evaluated the optimal dietary inclusion of palm kernel oil (PKO) for Nellore bulls on meat quality. The diets consisted of 0.0, 11.5, 23.0, and 34.6 g/kg dry matter (DM) PKO levels. PKO inclusion did not influence the centesimal composition, pH, color indices, water holding capacity, cooking loss, or shear force of the beef. There were linear increases in the concentrations of lauric acid (C12:0) and myristic acid (C14:0) in the bull’s meat. However, palmitic acid (C16:0), oleic acid (C18:0), vaccenic acid (t-11–C18:1) and conjugated linoleic acid (CLA), ∑n − 6, ∑n − 3, ∑n − 6/∑n 3, the hypocholesterolemic: hypercholesterolemic ratio of the fatty acid content, and the thrombogenicity index were not affected. There were linear reductions in the oleic acid meat concentration (c-9–C18:1) and elongated enzymatic activity when PKO was added to the bull diet. The atherogenicity index increased linearly due to PKO inclusion in the bull diet. No effect of the inclusion of PKO on meat flavor, perception of tenderness, juiciness, or global acceptance from the sensorial evaluation was recorded. The inclusion of PKO up to 34.6 g/kg DM can be recommended to supplement young bulls with no effects on meat composition and quality characteristics.

Buriti (Mauritia flexuosa L.) oil (BO) is a byproduct that can be incorporated into the diet of lambs, thus increasing the energy density. The study aimed to evaluate the optimum BO inclusion level in lamb diets. Sixty-five Santa Ines lambs were distributed in two completely randomized experiments with five treatments each (BO inclusion at 0 (control), 12, 24, 36 and 48 g/kg dry matter (DM) total). The BO supplementation to partially replace ground corn linearly decreased the nutrient intake and digestibility of DM, ether extract and neutral detergent fiber (NDF), N° chews/bolus, DM and NDF rumination or eating efficiencies, the N intake and N balance, carcass weights and yields, and dressing content of lamb carcasses (p < 0.05). The addition of BO responded quadratically to DM eating efficiency and N-fecal and N-urinary excretion (p < 0.05). The linear response plateau (LRP) analysis demonstrated that the levels of 0 and 12 g/kg of BO were similar, and improved intake and digestibility and consequently performance (p < 0.001). There was a linear increase in feed efficiency and shrinkage after chilling with the BO inclusion replacing ground corn. The inclusion of 12 g/kg BO in the total DM of diet is recommended, because it improves feeding intake, digestibility and performance of lambs.

Vegetable oils can be used to increase energy density in diets; manipulate rumen fermentation; and alter the capacity for degradation, digestion and absorption of nutrients. Two experiments were conducted to evaluate palm kernel oil (PKO) in the diet of confined bulls with the inclusion of 0.0, 11.5, 23.0 and 34.6 g PKO/kg dry matter (DM). The first experiment evaluated nutrient intake, performance, ingestive behavior and carcass characteristics. In the second experiment, steers crossbred with a ruminal cannula were used to evaluate digestibility, nitrogen balance, microbial protein synthesis, short-chain fatty acid levels and protozoal counts. The results showed that the inclusion of PKO linearly reduced intake in kg/day (DM, crude protein—CP, neutral detergent fiber—NDF_ap, nonfibrous carbohydrates—NFC and total digestible nutrient—TDN) and digestibility (DM, NDF_ap and TDN). Ether extract intake increased quadratically with the predicted maximum intake of 15.4 g/kg DM. Regarding ingestive behavior, there was a quadratic increase in rumination time and a quadratic reduction in idle time. Nitrogen balance, nitrogen intake, nitrogen retention, microbial protein production, acetate, butyrate, acetate/propionate ratio and protozoa count showed linear decreases due to dietary PKO inclusion. Regarding the carcass characteristics, linear decreases were observed for the final weight, average daily gain, hot carcass weight, cold carcass weight, hot carcass yield, cold carcass yield, loin eye area and subcutaneous fat thickness. The inclusion of PKO at up to 34.6 g/kg DM in diets for confined bulls reduces intake, negatively affecting digestibility, performance and carcass characteristics.