Nutritional requirements of nursing Nellore calves

Revista Brasileira de Zootecnia

Paulino, Pedro Veiga Rodrigues¹  Fonseca, Emílio Alves²  Fonseca, Mozart Alves²  Henriques, Lara Toledo¹  Silva, Leandro Diego da²  Benedeti, Pedro Del Bianco²  Valadares Filho, Sebastião de Campos²  Detmann, Edenio² 

[1] UFPB;UFV

关键词: efficiency;    energy;    lactating cows;    milk energy;    macromineral;    protein     Introdução O desenvolvimento do bezerro está diretamente associado à quantidade de leite fornecida ao animal e ao período de aleitamento (Roy;    1990);    uma vez que o leite é naturalmente o alimento desses animais em uma fase mais jovem e sua composição é compatível com a exigência nutricional neste estádio do desenvolvimento;   

DOI  :  10.1590/S1516-35982012000500019

学科分类：兽医学

来源: Universidade Federal de Vicosa

【 摘 要 】

This experiment was carried out to evaluate the nutritional requirements of protein, energy and macro minerals for Nellore calves from birth to 180 days. A total of 20 calves, 10 males (M) and 10 females (F) with average body weight (BW) of 30±3 kg were used. Soon after birth, four (2 males and 2 females) calves were slaughtered to estimate initial body composition of animals that remained in the trial. At 90 days, another eight calves were slaughtered (4 males and 4 females), and the remaining animals were slaughtered at 180 days. Besides milk, the calves were fed with corn silage ad libitum and commercial concentrate set at a maximum of 0.5 kg/animal/day. Two digestibility assay were conducted at 30 and 90 days to estimate the energy intake of the calves. After slaughtered all calves had their right half-carcasses dissected. The content of protein, energy and minerals were estimated by the equation Y = a. EBWb, where EBW is the empty body weight. The relationship EBW/BW of calves was 0.9622 and EBWG/BWG was 0.958, where G is the gain. The net requirements of protein and energy increased with increasing body weight, while calcium decreased. The metabolizable protein requirements for gain of 1 kg BW were 216.96 and 261.98 g for calves with 100 and 200 kg respectively. The following equations are recommended to estimate the body content of preweaning Nellore calves: protein (g/day) = 0.135 × EBW1.0351; energy (Mcal/day) = 1.1798 × EBW1.1805; calcium (g/day) = 0.091 × EBW0.6019; phosphorus (g/day) = 0.00894 × EBW0.9629; sodium (g/day) = 0.00126 × EBW0.9791; magnesium (g/day) = 0.000405 × EBW0.9827; potassium (g/day) = 0.00165 × EBW0.9364.

【 授权许可】

CC BY-NC