Digestibilidade aparente em bezerros de corte oriundos de vacas com suplementação injetável

Abstract

Objective to evaluate how injectable vitamin B12 supplementation in cows during the prepartum period could influence apparent digestibility in calves. Twenty multiparous cows in their 2nd to 4th lactation, with confirmed pregnancies from a fixed-time artificial insemination (FTAI) breeding season conducted on the farm, were used. The experimental period began when the pregnant cows entered the mid-third of gestation. All animals were weighed, identified, and subjected to ecto- and endoparasite control. Among the 20 pregnant cows, 10 were chosen to receive, in addition to the mineral supplementation in the trough, injectable supplementation containing available calcium and phosphorus, amino acids, and vitamin B12 (Roboforte®) in two applications: 20 mL at the beginning of the mid-third and 20 mL in the middle of the mid-third. The remaining 10 cows received only mineral supplementation in the troughs present in the paddocks. This stage of supplementation of the cows was concluded shortly after the birth of their offspring, considering an average period of 90 days for supplementation. To estimate pasture intake, LIPE (purified and enriched isolated lignin) was used as an external indicator. To measure the dietary intake of the calves, LIPE will be used to estimate forage consumption, plus milk consumption. The data were statistically interpreted through analysis of variance and F-test at a 0.05 probability level, in a completely randomized design, using the SAS program (version 9.1). The apparent digestibility of dry matter (DAMS) and the variables CP, NDF, NFC, and TDN were not significantly influenced by injectable vitamin B12 supplementation (P>0.05) in the mid-gestation period; among the variables, only the apparent digestibility of ether extract (ADEE) was significantly influenced (P<0.05) by injectable vitamin B12 supplementation. The use of injectable vitamin B12 supplementation in cows during the The mid-third of gestation had no significant effects on the apparent digestibility of most nutrients evaluated in calves; however, its use had a negative effect on the digestibility of ether extract.