Comportamento ingestivo de novilhas bubalinas alimentadas com níveis crescentes de concentrado em dietas com cana-de-açúcar

Abstract

The objective of this study was to evaluate the effect of the association of sugarcane with increasing levels of concentrate on the ingestive behavior of buffalo heifers. The experiment was conducted in the Bubalinoculture Sector of the Animal Science Department of UFRPE. Twenty buffalo heifers of the Murrah breed, with initial mean body weight of 100 ± 13 kg, were used in a completely randomized design with four treatments and five replicates. The study lasted for 84 days. Experimental diets were isoprotective, using sugar cane (stem) as bulky, and corn meal, wheat bran, soybean meal, mineral mixture and urea composing the concentrate that was offered at increasing levels (20, 40, 60 and 80%). Ingestive behavior (time spent on feeding, rumination and leisure) were measured by direct visual observation every 5 minutes in the daytime (06h00 to 17h55) and nocturnal (18h00 to 05h55) for 3 consecutive days (72h). One meal was considered a long feeding sequence with at least two successive feeding periods of 5 minutes. The minimum interval between meals was considered to be 20 minutes. There was a significant effect of the period for feeding time (FT), rumination (TR) and leisure (L) and on the frequency of meals (FM). Only the FT was affected by the inclusion of concentrate in the buffalo diet, observing less time in the diet with 80% concentrate. For the diurnal period the heifers spent more FT, TO and FM; beginning to ruminate more in the nocturnal period. It is believed that as the animals spent more time in the diurnal period with feeding, the nocturnal period was dedicated to rumination. The higher L at night can be explained by the fact that ruminants prefer to perform this activity in the period when the temperatures are milder, being these at night time. The buffaloes, in their moments of leisure, seek to immerse themselves in the water, and the animals in the present study were given baths throughout the day, providing greater comfort and greater permanence in that period. From this we can conclude that the ingestive behavior of buffaloes is influenced by the period of the day. Diets with higher proportions of concentrate influence the feeding time, where they gave more time from the diurnal period to activity related to the search for food and the nocturnal period for rumination.