Effects of Different Dietary Energy Level and Semen Collection Frequency on Buck's Semen Quality in Cashmere Goats

The experiment was aimed to study the effects of dietary energy level on body weights, serum testosterone concentrations and semen quality of Shaanbei White cashmere goat bucks.A total of 12 healthy bucks were selected and divided into 4 groups according to randomized block design with 3 replicates per group, each replicate included 1 buck.Four diets were formulated by the recommendation of NRC (1981, 2007) at 85%, 100%, 115% and 130%.The results showed as that the dietary energy level had extremely remarkable effect on bucks' ADG in each stage (P< 0.01).The weight of bucks in groups Ⅰ and Ⅱ decreased firstly then increased while there were a trend of increasing firstly then decreasing then increasing again in groups Ⅲ and Ⅳ.Serum testosterone levels and ejaculations under the frequency of two times per five days were higher as compared to the frequency of four times per five days.Dietary energy levels had extremely significant influence on serum testosterone concentrations and the number of effective sperms (P< 0.01), and ejaculations and sperm destiny significantly (P< 0.05).The ejaculations, sperm destiny and the number of effective sperms in group Ⅲ were optimum.There was dietary energy×semen collection frequency interaction on serum testosterone concentration (P< 0.01).It could be concluded that the appropriate ME requirement of Shaanbei White cashmere goat bucks was 12.08 MJ/d.