Feeding behavior of dairy cows fed different levels of castor meal in the diet

Abstract

This study aimed to evaluate the inclusion of castor meal in the diet of lactating cows in grazing system and its implications in feeding behavior. Eight Holstein x Zebu crossbred cows, with average milk production adjusted to 300 days in the previous lactation, between 5000 and 6000 kg and 100.33 ± 13.33 days of lactation and average body weight of 509.47 ± 61.90 kg, were distributed in two 4 x 4 Latin squares, with 4 levels of castor meal inclusion in the total diet, and using Brachiaria brizantha pasture as roughage. The experiment consisted of four experimental periods, lasting 21 days each. In each trial, the roughage and supplements were collected for evaluation of chemical composition. Animals were subjected to visual observation for evaluation of feeding behavior for 24 hours, from the 20 th to the 21 st day of each experimental period. The observations of the activities were recorded every five minutes.We determined the number of ruminating chews and the time spent in rumination of each ruminal bolus with the use of digital stopwatch. There was a quadratic effect for the grazing time with maximum point of inclusion of castor meal at 4.61% in the diet; other variables did not differ: rumination, idleness, trough, rumination efficiency, feeding and grazing time, rumination and idleness. Castor meal can be included in the diet with levels up to 10%, for little changes in the feeding behavior of animals.

Ruminal degradation of dry matter, crude protein and fiber fraction of oilseed byproducts

“…Ruminant production in Brazil is based on the use of forage plants as one of the major sources of nutrients for animals (RIGUEIRA et al, 2018;SANTANA et al, 2019). However, forage production is not constant throughout the year, which makes it a limitation of animal production only on pasture forage (OLIVEIRA et al, 2014;SOUZA et al, 2015). Among the planning strategies to maintain milk and meat production throughout the year, we highlight the conservation (i.e.…”

“…Among the planning strategies to maintain milk and meat production throughout the year, we highlight the conservation (i.e. deferment, silage, hay) of the surplus of forages traditionally grown in each region, as well as the use of alternative food sources such as the byproducts of oilseeds produced in agroindustries (SOUZA et al, 2015;RIGUEIRA et al, 2018). The byproducts and coproducts generated in the production of biodiesel present potential to be used in the supplementation of ruminants due to the concentration of nutrients such as non-fiber carbohydrates, ether extract, crude protein and minerals (GOES et al, 2011).…”