Associação da eficiência alimentar com o comportamento ingestivo de bovinos da raça Nelore

Abstract

The objective of this study was to associate feed efficiency with ingestive behavior in male Nellore cattle. The animals originated from two feed efficiency trials, totaling 29 animals in the first trial (Lot A), lasting 56 days, with a mean age of 18 months, and 24 animals in the second trial (Lot B), lasting 42 days, with a mean age of 21 months. Two contemporary groups of Nellore PO bulls were used. Feed efficiency was measured using residual feed intake (RFI), while ingestive behavior was evaluated using four behavioral parameters: Number of visits to the feed bunk with intake (NVC); Time at the feed bunk with intake (TCC); Feeding rate per hour (TAH); and Feeding rate per visit (TAV). The electronic feed bunk system used during the FET was Vytelle®, which generates RFI results and ingestive behavior parameters. Statistical analyses included Pearson’s correlation at a 5% significance level, analysis of variance (ANOVA) followed by Tukey’s test at 5% significance, and regression analysis for average daily gain. RStudio®, R Core Team, and ExpDes.PT were used for the analyses. The correlations observed were: RFI and TAH (0.52) and RFI and DMI (0.52) for Lot A; and RFI and TAH (0.86) and RFI and DMI (0.86) for Lot B. No significant or moderate correlations were observed for the other variables. The analysis of variance demonstrated that RFI influenced TAH and DMI in Lot A and, in Lot B, whereas the other ingestive behavior variables did not show statistically significant differences among treatments and classes. It was concluded that there was an association between feed efficiency and ingestive behavior in Nellore cattle, particularly with dry matter intake and feeding rate per hour, as expected. Animals with negative RFI showed lower dry matter intake without compromising average daily gain, while the behavioral variables did not differ among the RFI classes.