Produção de leite e parâmetros fisiológicos de cabras puras e mestiças Parda Alpina no Estado da Paraíba.

Abstract

This study aims to evaluate and quantify the quality and production o f milk, as well as the physiological parameters of pure and crossbred Alpine brown goats, in confinement system in Mulungú - PB, meso-region of the Agreste from Paraíba state. The research has been carried out in two distinct times: the first between July and August 2010, corresponding to the rainy season and the second between January and February 2011, corresponding to the drought season. It has been used 27 Alpine brown goats, being nine of them considered as purebred animais, nine with 3A and nine with Vi Alpine brown blood. The climatic factors have been monitored during the whole experiment inside the installations. The physiological variables rectal temperature, respiratory frequency, cardiac frequency and surface temperature, have been measured three times a week in three different schedules 8, 12 and 16 h. The milk production control has been made weekly during four weeks. Once a week, it has been collected milk samples, soon after the milky has been performed and they have been kept cooled, and sent to the Analysis Laboratory of Animal Products (LAPOA) from the Agriculture Sciences Center CCA/UFPB to be analyzed. The evaluation of the milk quality has been made through microbiological analysis, somatic cells counting and the evaluation of the chemical and physical features. Data have been evaluated through variance analysis, being the averages compared by the Tukey test with 5% error probability. The results have indicated that does not matter the period of the year, it has been observed that in the afternoon shift has occurred greater environmental discomfort for the animais, due the TR, FR, FC and TS are higher, making the goats more susceptible to thermal stress. The animais from the genetic groups lA and 3A Alpine Brown by presenting the lower FR, in order to keep the homeothermy, seems to be more adapted to the experiment conditions. Increasing the Alpine brown blood, the milk production has increased (p<0,05) till the 3A blood degree, but then fell with purebred animais regarding the interaction environment/genotype. It has been observed that through the physical and chemical analysis, every milk components are according to the established standards by the current law, independem of the studied period. The bacterial counting was according to the normal standards, both as regards the time of the year and the genetic group. It has been concluded that, the Alpine brown goats, mainly the purebred ones, have gone through stressful situations when raised in tropical climate and there is a variation in the milk production, being the drought season the most criticai for animais, being the results consistent with the physiological responses.