Adaptabilidade e características nutricionais de caprinos Anglo Nubiano em diferentes temperaturas.

Abstract

The objective of this study was to determine the adaptability and nutritional characteristics of Anglo Nubian goats at different temperatures. The work was developed in a climate chamber using six males and castrated, who underwent four climatic conditions, 20oC - temperature lower limit of Thermal Comfort Zone (TCZ); 24oC - within the TCZ; 28oC - within the TCZ and 32oC - above the TCZ, with fixed relative humidity (RH) of 60%. Data relating to air (AT), RH, dew point (DP) temperature and black globe temperature (BGT) for determining the temperature BGT were collected, and physiological parameters such as respiratory rate (RR), heart rate (HR), rectal temperature (RT) and surface temperature (ST) for the determination of heat tolerance as Iberia or Rhoad and adaptability of tests like Benezra (AC1 and AC2), test the determination of thermal gradients was done by the difference between rectal and surface temperatures (RT-ST) and between the surface and ambient temperatures (ST-AT) as adaptability parameter. For the evaluation of the technique of feeding behavior instantaneous scan every five minutes was used. For nutrient intake and digestibility animals were kept in cages for determination of metabolism during the entire experimental period making the total collection of feces, feed and feed leftovers. The experimental design was completely randomized with four treatments (temperature), six replicates (animals). Data were evaluated by analysis of variance, and when significant, were compared by Tukey test at 5% probability for determining the nutrient intake regression analysis was done. The results indicated that the BGHI temperatures 20, 24 °C gave adequate weather race. Statistical difference was observed with increasing temperature for the ST, HR and RR, and the RT remained constant and within normal limits. For the physiological parameters and temperature gradients, temperature effect was observed (P<0.05) with increasing temperature within the chamber, as well as the records for the Iberia and AC1 and AC2 test, with change with increasing temperature inside the chamber. Chewing behavior there was a greater demand for water with increasing temperature and there was a decrease in food intake, but there were no differences for the consumption of nutrients (EEC, CP and NDF). Thus we can say that Anglo Nubian goat breed is demonstrated highly-adapted conditions studied.