Energy requirements for maintenance and growth of Canindé goat kids

Abstract

Accurate values for energy requirements are necessary for the proper feeding management of goats. The aim of this study was to estimate the energy requirements for maintenance and growth of Canindé goat kids. We used 33 castrated goat kids with an average initial weight of 15.62±0.87kg. Five of them (baseline) were slaughtered at the beginning of the experiment to determine the initial body composition. The other goats (n=28) were assigned in a randomized block design into seven groups of four animals each. The diet consisted of 55% forage (Tifton) and 45% concentrate. The treatments consisted of four levels of intake: ad libitum and 80%, 60% and 40% of the ad libitum intake. Each group was slaughtered when the animal from the ad libitum level reached 26.55±0.65kg. We used the comparative slaughter method to assess body composition and calculate the nutritional requirements. Body composition varied from 177.43 to 166.98g of protein, from 127.92 to 193.46g of fat and from 2.15 to 2.69Mcal of energy per kg of empty body weight (EBW). The ratio of empty body weight/body weight was 0.81. The net energy requirements for maintenance were estimated at 52.64kcal/kg EBW0.75. The net requirements to gain ranged from 2.96 to 4.84Mcal/kg EBW gain for the castrated indigenous goat kids weighing between 15kg and 25kg. The energy requirements to maintenance of indigenous goat kids are lower, which might indicate different adaptive capabilities, but these goats require more energy to gain and to accumulate fat in their body.