Suchergebnisse

The objective of this trial was to evaluate the effect of the partial replacement of corn by forage cactus (Nopalea cochenillifera Salm Dyck) in the diets of lactating goats on the nutrient intake, milk production and composition and ingestive behavior. Five crossbreed Saanen x Pardo Alpina goats with body weights of 47 ± 3.3 kg were used in the study. The design was 5x5 Latin square design, in which the treatments were as follows: 20, 25, 30, 35 and 40% of girl cactus included in the diet as a partial replacement of corn, with 0, 18, 36, 54 and 72% of the added the cactus comprising of gliricidia (Gliricidia sepium (Jacq) Walp) as roughage in all treatments. Treatment did not affect (P > 0.05) the dry matter intake, crude protein, neutral detergent fiber, acid detergent fiber and total digestible nutrients with the increasing levels of cactus in the diet, presenting means of 1.64, 0.26, 0.82, 0.54 and 1.17 kg day-1, respectively. In the same way, no influence was observed on the daily milk production and levels of fat, protein, lactose and total solids of milk, which averaged 1.18 kg day-1; 3.74, 3.34, 5.06 and 13.56%, respectively. The inclusion of cactus also had no influence (P > 0.05) on the ingestion behavior. The treatment with 35% cactus showed a lower impairment of food intake (31%). The partial replacement of the corn by the girl cactus in the diets of dairy goats can be accomplished because it does not alter the intake, milk yield and composition and feeding behavior. The replacement of up to 54% corn by the cactus is recommended to reduce producer costs for food.

This study aims to validate, by means of subcutaneous rump fat thickness (RFT), the suitability of the visual evaluation of body condition score (BCS) to indicate the body condition of crossbred dairy cows (Holstein x Zebu) during the transition period and early lactation. Animals were selected according to lactation period and distributed into three groups: PP (0 to 4 weeks antepartum; n = 30), L4 (0 to 4 weeks postpartum; n = 15), and L + 5 (5 to 14 weeks postpartum; n = 63). The relationship among RFT, BCS, and body weight (BW) was investigated using correlation and regression analyses. The variables BCS, RFT, and BW were different among the three groups (P < 0.05). The correlations between BCS and RFT were higher in groups PP and L + 5 (r = 0.78 and r = 0.71 respectively). However, the L4 group showed a weak correlation (r = -0.04). The regression models were able to explain how much RFT varies because of changes in BCS, with coefficients of determination equal to 0.61 for PP and 0.51 for L + 5 group. In conclusion, BCS can be considered a good predictor of RFT for crossbred Holstein x Zebu cows in antepartum and postpartum for over 5 weeks of lactation.