Effects of Ambient Temperature on Milk Production of Nubian and Alpine Goats

Sets of six Nubian and six Alpine goats were housed at 20, 27, and 34°C during each of two lactation trials. In the first trial, milk production from Nubians and Alpines was similar, but Nubians ate more and had lower milk to feed ratios than Alpines. In the second trial, Nubian milk, solids, fat, and N production (averaged over the entire temperature range) were only 62, 71, 75, and 80% of the respective Alpine component production, despite the fact that Nubian milk had higher percentages of solids, fat, and N than Alpines. Although Alpines ate more than Nubians in the second trial, these Alpines exhibited higher milk solids to feed intake ratios. Significant breed by temperature interactions observed during the second trial indicated that increasing temperature depressed milk, solids, fat, and N yields more in Alpines than in Nubians.