One hundred two animals were evaluated to develop prediction equations for estimating hind-quarter composition from live animal ultrasound measurements and to compare these equations with those developed from carcass measurements. To develop prediction equations used all-possible regressions procedure for variables reductions and stepwise regression. Final models using live animal variables included live weight (PVUS), Longissimus muscle area (ULMA) and fat thickness (UFAT) for weight (PCTT; R² = 0.78) and percent (RCTT; R² = 0.18) of hind-quarter retail product. The models […]

Grasslands are being replaced by urbanization and more profitable agricultural activities around the world. Producers may be faced with land constraints and need to consider intensification of the remaining grasslands as a means of maintaining overall production on a decreasing land resource. However, intensification of the grazing system is usually associated with greater nutrient inputs, including those from commercial fertilizers and supplement fed to animals. Excessive loading of nutrients in intensive grazing systems via fertilizer and animal wastes can cause […]

The objectives of this trial were to estimate the body composition of fat and protein and the net energy requirements for maintenance of purebred and crossbred Nellore. Seventy-two young bulls averaging 10 to 11 months of age from four genetic groups were used: 18 Nellore, 18 F1 Nellore x Angus, 18 F1 Nellore x Brown Swiss and 18 F1 Nellore x Simental with initial average weights of 286, 309, 333 and 310 kg, respectively. A completely randomized design was adopted […]

In situ DM and CP degradabilities of leaflets of three tropical legumes: leucaena (Leucaena leucocephala (Lam.) de Wit), pigeon pea (Cajanus cajan (L.) Millsp.), and glycine (Neonotonia wightii) and of leaves of two other tropical forages: ramie (Boehmeria nivea (L.) Gaudich) and cassava (Manihot esculenta Crantz) were determined in this trial. Three grams of pigeon pea, glycine, and ramie and 5 g of leucaena and cassava were incubated in the rumen of four steers for 3, 6, 12, 18, 24, […]

The objective of this work was to evaluate the inter treatment discrimination according to feed conversion efficiency in several animal performance experiments. The variables investigated were: feed conversion ratio (FCR = intake: production ratio), feed efficiency index (FEI = production: intake ratio) and bio-nutritional index (BNI). The BNI was constructed from the first canonical variable obtained based on the multivariate analysis of variance of the intake and animal production (weight gain or milk production) variables. The results indicated that FCR […]

The objective of this trial was to estimate the upper critical levels of the temperature-humidity index (TUI) measuring morning and afternoon rectal temperature (RT), respiratory rate (RF), and hair coat surface temperature (ST) of ½, ¾ and 7/8Holstein-Zebu (HZ) dairy cows during two consecutive years (two summers and two winters) in Coronel Pacheco, MG, Brazil. Correlation and multiple analysis were determined using data obtained from 15 dairy crossbreed cows/season; five from each genetic group (GG). Results showed that RF was […]

Four ruminally and duodenally cannulated Nellore steers were assigned to a 4 x 4 latin square to study the effects of feeding monensin (M) and different sources of fat on the ruminal population of ciliate protozoa and ruminal pH. The experimental diets contained (DM basis) 19% of sugar cane and were supplemented with M [control (CTRL)], M plus calcium salts of fatty acids (CSFA), M plus whole cottonseed (MWCS), or only WCS. Ruminal contents were sampled at 0, 2, 4, […]

The objective of the experiment was to evaluate, through feedlot performance of calves, three corn hybrids (Zea mays, L.): Agroceres AG-5011, Braskalb XL-344 and Cargill C-806. For the evaluation, 27 Nellore x Charolais non-castrated crossbred males with average age of 10 months and average initial weight of 252 kg, were used. The animals were fed during 84 days, divided in four periods of 21 days. The hybrids silages tested represented 70% of the dry matter offered. No significant interaction of […]

The objective of this experiment was to compare fat and cholesterol content, and fatty acids (FA) profile in Longissimus dorsi muscle of castrated and young bulls from Nellore (NE) and ½ Nellore x Sindi (NS) cattle and Mediterranean buffaloes. Eight animals (four castrated and four young bulls) per genetic group was used, with a total of 24 animals. A completely randomized experimental design in a 3 x 2 factorial arrangement (three genetic groups and two sexual conditions) was used. Animals […]

The study was carried out to develop predictions equations of the physical and chemical composition of dairy calves carcass. Eighteen Holstein bulls calves weighing between 30 and 100 kg were used. Groups of six animals were slaughtered at birth, 50 and 110 days of age. The carcass was divided in forequarter, rib, hindquarter and 9-11th rib section and dissection of each part was carried out. The physical and chemical composition was determined by a direct method and prediction equations were […]