The objective of this study was to determine whether nutrient digestibility and reproductive performance of pregnant mink(Neovison vison) were affected by different dietary protein levels. One hundred and twenty femal...The objective of this study was to determine whether nutrient digestibility and reproductive performance of pregnant mink(Neovison vison) were affected by different dietary protein levels. One hundred and twenty female mink were randomly assigned to four groups, receiving diets of fresh material with different protein levels. The dietary protein levels,expressed as percentage of dry matter(DM),were 32,36, 40 and 44% respectively. These values corresponded to average 320, 360, 400 and 440 g protein/kg DM, respectively. Results were as follows. All of crude protein digestibility, nitrogen(N) intake, N retention increased along with dietary protein level increasing. Low protein level(32%) significantly reduced the above indicators(P < 0.05). DM digestibility and ether extract digestibility were not affected by dietary protein level. Results of mated females, barren females, kids per litter, live born kids per mated female, birth survival rate, and birth weight showed that mink achieved optimal reproductive performance when dietary protein level was 36%. In conclusion, dietary protein was anticipated to significantly influence some nutrients' utilization. Adopting the appropriate dietary protein level allow better reproduction performance. The most preferable reproductive performance was achieved when diet contained 275.5 g digestible protein per kg DM for female mink in gestation.展开更多
本文基于不同分析和取样方法研究褪黑激素对育成期母貂行为分配的影响。从貂场中随机选取当年出生的6只未埋植褪黑激素、6只埋植褪黑激素的美国短毛黑母貂。采用高清摄像头分别在埋植褪黑激素后的第30天(Ⅰ期)、第60天(Ⅱ期)、第75天(Ⅲ...本文基于不同分析和取样方法研究褪黑激素对育成期母貂行为分配的影响。从貂场中随机选取当年出生的6只未埋植褪黑激素、6只埋植褪黑激素的美国短毛黑母貂。采用高清摄像头分别在埋植褪黑激素后的第30天(Ⅰ期)、第60天(Ⅱ期)、第75天(Ⅲ期)记录所有水貂的行为。埋植褪黑激素对水貂行为分配的影响,混合线性模型(mixed linear model,MLM)和广义线性混合模型(generalized linear mixed model,GLMM)对于水貂的位置、采食、修饰、异常和饮水行为的分析结果不同,广义线性混合模型的分析结果更符合褪黑激素已知的作用效果;瞬时取样间隔≤1.5 min时,水貂的所有行为比例与连续取样无显著差异(P>0.05)。由此可以推断,广义线性混合模型更适合无法正态化的实验数据的分析;采用瞬时扫描取样法研究水貂行为分配,扫描时间间隔以1.5 min为宜。展开更多
基金The financial support is from Special Fund for Public Welfare Technology Research of Agricultural Industry(200903014)Supporting Plan for Scientific and Technological Research of Jilin Province(20090238)
文摘The objective of this study was to determine whether nutrient digestibility and reproductive performance of pregnant mink(Neovison vison) were affected by different dietary protein levels. One hundred and twenty female mink were randomly assigned to four groups, receiving diets of fresh material with different protein levels. The dietary protein levels,expressed as percentage of dry matter(DM),were 32,36, 40 and 44% respectively. These values corresponded to average 320, 360, 400 and 440 g protein/kg DM, respectively. Results were as follows. All of crude protein digestibility, nitrogen(N) intake, N retention increased along with dietary protein level increasing. Low protein level(32%) significantly reduced the above indicators(P < 0.05). DM digestibility and ether extract digestibility were not affected by dietary protein level. Results of mated females, barren females, kids per litter, live born kids per mated female, birth survival rate, and birth weight showed that mink achieved optimal reproductive performance when dietary protein level was 36%. In conclusion, dietary protein was anticipated to significantly influence some nutrients' utilization. Adopting the appropriate dietary protein level allow better reproduction performance. The most preferable reproductive performance was achieved when diet contained 275.5 g digestible protein per kg DM for female mink in gestation.
文摘本文基于不同分析和取样方法研究褪黑激素对育成期母貂行为分配的影响。从貂场中随机选取当年出生的6只未埋植褪黑激素、6只埋植褪黑激素的美国短毛黑母貂。采用高清摄像头分别在埋植褪黑激素后的第30天(Ⅰ期)、第60天(Ⅱ期)、第75天(Ⅲ期)记录所有水貂的行为。埋植褪黑激素对水貂行为分配的影响,混合线性模型(mixed linear model,MLM)和广义线性混合模型(generalized linear mixed model,GLMM)对于水貂的位置、采食、修饰、异常和饮水行为的分析结果不同,广义线性混合模型的分析结果更符合褪黑激素已知的作用效果;瞬时取样间隔≤1.5 min时,水貂的所有行为比例与连续取样无显著差异(P>0.05)。由此可以推断,广义线性混合模型更适合无法正态化的实验数据的分析;采用瞬时扫描取样法研究水貂行为分配,扫描时间间隔以1.5 min为宜。