Exigências nutricionais de caprinos da raça alpina em crescimento. 1.Exigência nutricional de cálcio para mantença: Frações endógenas e abate comparativo

Abstract

This experiment was conducted to estimate the dietary calcium maintenance requirements for kid goats in the growing phase by the endogenous loss method and comparative slaughter technique. Twenty-one male, four-month-old kid goats, average live weight of 20 kg, were used. Three animals were slaughtered at the beginning of the experiment and the other 18 animals were distributed to three isocaloric and isoproteic diets with three levels of calcium (Ca) (.04,.12, and .24%). The experimental period was 27 days with a 20-day adaptation period and seven days of total fecal and urine collection. At the end of the collection period, three animals were slaughtered from each treatment. Average values for the absorption coefficients were: -1.01, .35, and .77; for fecal loss: 35.24, 37.36, and 55.59 mg of Ca/W.75/day; for urinary loss: 3.72, 4.17, and 4.71 mg of Ca/W.75/day; and for Ca balance: -21.26, 15.80, and 54.24 mg of Ca/W.75/day for the three respective Ca treatments. Fecal and urinary endogenous losses were estimated to be 27.77 and 3.25 mg of Ca/W.75/day, respectively. The estimated dietary Ca maintenance requirements were 40.82 mg of Ca/W.75/day and 52.85 mg Ca/W.75/ day by the endogenous fractions loss and the comparative slaughter techniques, respectively.