Effects of Cold Exposure on Some Physiological Productive and Metabolic Variables in Lactating Dairy Goats

摘要

In the current study the impact of cold temperatures (CT; −3 to 6 °C) on milk production and metabolism was evaluated in dairy goats. Compared to goats in thermoneutral conditions (TN; 15 to 20 °C), CT goats produced lower amounts of milk, but their milk contained more fat and protein. Consequently, the yield of energy-corrected milk did not vary between TN and CT goats. Additionally, feed intake did not vary between treatments. The CT goats mobilized body fat reserves to spare glucose and cover the increased needs for heat production under low temperatures. In conclusion, CT goats produced lower milk yield, but their milk contained greater fat and protein compared to TN goats. Furthermore, cold temperatures induced metabolic changes that included body fat mobilization without changes in blood insulin values.