Correlação entre produção e composição do leite e comportamento ingestivo de vacas lactantes alimentadas com dietas contendo silagens de cana-de-açúcar

Abstract

This work aimed to evaluate the correlations between production and milk composition and feeding behavior of lactating cows. The cows had an average of 100 days of lactation and a production were arranged in two 4 × 4 Latin squares conpound of the four periods, four diets and four animals. The diets were formulated to be isonitrogenous with roughage: concentrate ratio of approximately 55:45. As forage, were evaluate four silages sugar cane: without additive (control), with 1% urea, with 0.5% urea + 0.5% CaO and with 1% CaO. The experimental period lasted 60 days divided into four periods of 15 days. Feeding behavior was assessed on the 13 day of each experimental period, for 24 hours, every five minutes. From the data 24 behavioral variables were determined, which were correlated with the data of production and milk composition. The behavioral variable eating and ruminating, DM intake in grams/day, rumination efficiencies in grams of DM and neutral detergent fiber were positively correlated (P<0.05) with milk production in kg/day and the production corrected for 4% fat. However, there was a negative correlation between feeding time and the milk fat percentage. Despite the low values of the correlations can be inferred from the results, the data can be used to develop models to predictyield and composition of milk from the feeding behavior variables.