不同钙水平日粮对云南半细毛羊泌乳期能量代谢的影响

本试验旨在研究不同钙水平日粮对泌乳期云南半细毛羊能量代谢的影响。选取50只年龄接近的经产二胎云南半细毛羊做同期发情处理，产羔前15 d按体重随机分为5个处理组，每组10只母羊，各组试验羊饲喂钙水平分别为0.35%、0.42%、0.61%、0.75%和0.96%，日粮其他营养成分保持一致。正试期90 d。结果表明：①消化能和代谢能：在泌乳前期、中期和后期，0.42%、0.75%和0.96%钙水平组显著或极显著高于0.35%和0.61%钙水平组（P < 0.05；P < 0.01）。②泌乳净能：泌乳前期不同钙水平组差异不显著（P > 0.05）；中期0.42%和0.96%钙水平组显著高于0.35%钙水平组（P < 0.05）；后期0.35%钙水平组最低，其余4个钙水平组间差异不显著（P > 0.05）。③总能消化率：泌乳前期0.35%和0.96%钙水平组显著高于0.42%钙水平组（P < 0.05）；中期0.35%钙水平组显著高于0.42%和0.75%钙水平组（P < 0.05）；后期不同钙水平组间无显著差异（P > 0.05）。④总能代谢率：泌乳前期和后期不同钙水平组差异均不显著（P > 0.05）；中期0.35%钙水平组显著高于0.42%、0.61%和0.75%钙水平组（P < 0.05）。⑤消化能代谢率：泌乳前期0.75%钙水平组比0.61%和0.96%钙水平组显著增加（P < 0.05）；中期0.35%钙水平组显著高于0.96%钙水平组（P < 0.05）；后期不同钙水平日粮组间差异不显著（P > 0.05）。综上所述，无论在泌乳前期、中期还是后期，云南半细毛羊母羊的消化能和代谢能摄入量均以0.42%钙水平组最佳，泌乳中期泌乳净能以0.42%钙水平组最高，泌乳前期和中期总能消化率则以0.35%钙水平组最高，泌乳中期总能代谢率、消化能代谢率均以0.35%钙水平组最高。因此，日粮钙水平在0.35%~0.42%之间时有利于云南半细毛羊泌乳期母羊的有效能摄入量和能量的利用效率。

A Effects of Different Dietary Calcium Levels on Energy Metabolism of Yunnan Semi-Fine Wool Sheep During Lactation

The purpose of this experiment was to study the effect of different calcium(Ca) levels on energy metabolism of Yunnan semi-fine wool sheep during lactation.50 Yunnan semi-fine wool sheep were randomly divided into 5 groups according to their weights 15 days before lambing.Each group was fed with 10 ewes.The calcium levels of each group were 0.35%,0.42%,0.61%,0.75% and 0.96% respectively.The normal trial period was 90 days.The results showed that:① DE and ME:0.42%,0.75% and 0.96% Ca level groups were significantly higher than 0.35% and 0.61% Ca level groups (P < 0.05;P < 0.01).② Net energy of lactation(NEL):There were no significant difference in different Ca levels of diets in the early lactation period (P > 0.05);In the middle period,0.42% and 0.96% Ca level groups were significantly higher than 0.35% Ca level group (P < 0.05).In the later period,0.35% Ca level group was the lowest,and there were no significant difference among the other four Ca level groups (P > 0.05).③ DE/GE:0.35% and 0.96% Ca levels in the early lactation group were significantly higher than 0.42% Ca levels (P < 0.05).0.35% Ca levels in the middle lactation group were significantly higher than 0.42% and 0.75% Ca levels (P < 0.05).There was no significant difference between different Ca levels in the later lactation group (P > 0.05).④ ME/GE:There was no significant difference in different Ca levels in the early and late lactation (P > 0.05).In the middle stage,0.35% Ca level group was significantly higher than 0.42%,0.61% and 0.75% Ca level groups (P < 0.05).⑤ ME/DE:0.75% Ca level group in the early lactation period was significantly higher than 0.61% and 0.96% Ca level groups (P < 0.05).0.35% Ca level group in the middle period was significantly higher than 0.96% Ca level group (P < 0.05).There were no significant difference under different Ca level diets in the later period (P > 0.05).In conclusion,no matter in the early stage,middle stage or later stage of lactation,the intake of digestive energy and metabolizable energy of Yunnan semi-fine wool sheep were the best in the 0.42% Ca level group,the highest in the 0.42% Ca level group in the middle stage of lactation,the highest in the 0.35% Ca level group in the early and middle stage of lactation,and the highest in the 0.35% Ca level group in the middle stage of lactation.Therefore,when the dietary Ca level was between 0.35% and 0.42%,it was beneficial to the effective energy intake and energy utilization efficiency of Yunnan semi-fine wool ewes during lactation.