Status metabólico e etologia de cabras em lactação, mantidas em ambiente tropical

Abstract

The aim of this study was to determine the metabolic status of lactating goats from three genetic groups (Saanen, Moxotó and Anglo-Nubiana), as well as the social, feeding and locomotion behavior of the same animals during the transition phase when kept in tropical conditions. This study was conducted at the Experimental Farm of Entre Rios, Bahia, belonging to the School of Veterinary Medicine and Zootechnics of UFBA. The goats of each genetic group were kept in collective pen and the densities were 2 m²/ animal/pen, distributed randomly. The etogram of three consecutive days per animal was described: prepartum, at parturition and postpartum, with the following time intervals: T1 = 5:00 to 6:30 a.m. T2 = 8:00 to 10:30 a.m. T3 = 12.00 to 13.30 pm; T4 = 3:30 p.m. to 5:00 p.m. and T5 = 7:00 p.m. to 8:30 p.m. In order to monitor the animals, infrared cameras with high definition recording were installed in the bays, and the following activities were recorded: idle, walking and standing time, standing and standing time, agnostic and non-agnostic interaction, exploratory, Self-contact, in rumination and in feeding. Immediately at parturition (day 0) and weekly, the blood collections were performed. Analyzes of glucose, cholesterol, triglycerides, HDL, LDL, VLDL, albumin, total protein, calcium, magnesium, phosphorus and urea were performed. The milk production was measured every fifteen days calving, and was completed at 45 days of lactação, totaling three measurements at the end, milk samples were taken on the same day of the measurement, for the analysis of the milk fat content. It was verified that the goats presented variation in the behavior for both the periods and the daytime hours, in the idle, standing, moving and feeding (P <0.05). Agnostic interactions demanded 3.33, 7.98 and 4.52% of goats' time on the day of calving. There was a period effect for the exploratory activities (P <0.05), where the highest number of activities was observed on the day of delivery (15.3% of the time). The milk production and fat content of Saanen, Anglo- Nubiana and Moxotó goats differed according to race and lactation week (P> 0.05), but there was no interaction between these two variables. No difference was found for races in the concentrations of energy, protein and mineral metabolites (P> 0.05). Blood concentrations of energetic metabolites suggest that there was no clinical picture of negative energy balance (BEN). The reduced concentration of blood calcium in the first week after calving suggests hypocalcemia in goats. Collective bays for lactating goats, kept in a tropical environment, do not compromise the natural behavior and level of well-being. It is suggested that greater attention be paid to the mineral balance of goats during the transition period.