Seasonal variation in voluntary feed intake and growth in cashmere bucks fed ad libitum diets of low or high quality [goats]
1994
Walkden-Brown, S.W. | Norton, B.W. (Queensland Univ., St Lucia (Australia). Dept. of Agriculture) | Restall, B.J. (New South Wales Agriculture, Wollongbar (Australia). Wollongbar Agricultural Inst.)
Diets were high (pelleted lucerne, CP 17.6 percent, ME 8.3 MJ per kg) or low (pasture hay; CP 6.9 percent, ME 6.6 mJ per kg) quality. Bucks on both diets exhibited a seasonal pattern in voluntary feed intake with maximal intakes during spring and summer, and minimal intakes during autumn. The pattern appeared to be circannual with high intakes during spring of both years. Liveweight also varied with season peaking in mid to late summer and reaching a seasonal nadir in late autumn or early winter. Change in liveweight was closely associated with digestible energy intake resulting in a growth cycle closely resembling that of voluntary feed intake. It was concluded that mature cashmere bucks exhibit an annual growth cycle with weight loss during autumn and maximal weight gains between mid-winter and mid-spring; that the growth cycle is driven primarily by changes in voluntary feed intake; and that increasing diet quality does not reduce the autumnal decline in liveweight but significantly increases liveweight gain during the seasonal peak in growth.
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