【作者】 王静；

【导师】 李光玉；

【作者基本信息】 中国农业科学院 ， 农业推广硕士（专业学位）， 2018， 硕士

【摘要】 本论文以生长期（育成期和冬毛期）水貂为研究对象,通过固定钙磷比,配制不同维生素D和钙水平的水貂饲粮,研究饲粮不同维生素D和钙水平对生长期水貂生产性能的影响,以筛选出水貂育成期和冬毛期适宜饲粮维生素D和钙水平,为指导实际生产提供理论依据。本研究包括两部分:第一部分:育成期水貂饲粮适宜维生素D及钙水平的研究随机选取（60±5）日龄健康短毛黑公貂117只,随机分成9组,每组13个重复,每个重复1只。试验采用3×3双因素随机试验设计,基础饲粮中维生素D水平为2 100 IU/kg,钙水平为2.3%,钙磷比固定为2:1。设3个维生素D（以维生素D₃形式）添加水平（0 IU/kg、2 000 IU/kg、4 000IU/kg）和3个钙添加水平（0%、0.4%和0.8%）。九组饲粮维生素D和钙水平分别为:Ⅰ组（2 100IU/kg×2.3%）、Ⅱ组（4 100 IU/kg×2.3%）、Ⅲ组（6 100 IU/kg×2.3%）、Ⅳ组（2 100 IU/kg×2.7%）、Ⅴ组（4 100 IU/kg×2.7%）、Ⅵ组（6 100 IU/kg×2.7%）、Ⅶ组（2 100 IU/kg×3.1%）、Ⅷ组（4 100IU/kg×3.1%）、Ⅸ组（6 100 IU/kg×3.1%）,预试期13 d,正试期60 d。结果表明:1)饲粮维生素D和钙水平对育成期水貂的末重、平均日增重、料重比均有极显著影响（P<0.01）,末重、平均日增重均以Ⅷ组最高,Ⅰ组最低;料重比Ⅷ组最低,Ⅰ组最高。2)育成期水貂脂肪消化率Ⅱ、Ⅳ、Ⅴ组极显著高于Ⅶ、Ⅷ组（P<0.01）。0.8%钙添加水平的干物质排出量显著高于（P<0.05）、脂肪消化率极显著低于（P<0.01）另两个水平。2 000 IU/kg维生素D添加水平的干物质排出量极显著低于（P<0.01）、干物质消化率和脂肪消化率显著高于（P<0.05）另两个水平。3)氮沉积随饲粮钙水平的升高而增加,以钙添加水平为0.8%时最高（P<0.05）。维生素D添加水平为2 000 IU/kg时育成期水貂的净蛋白质利用率、蛋白质生物学价值显著高于另两个水平（P<0.05）。4)粪钙、粪磷随着钙水平的升高而显著增加（P<0.05）。维生素D添加水平为2 000 IU/kg时,钙、磷消化率最高（P<0.05）。5)维生素D添加水平为2 000 IU/kg时,血清总蛋白浓度、25-羟维生素D浓度显著高于4 000IU/kg维生素D添加水平（P<0.05）。0%钙添加水平的血清25-羟维生素D浓度显著低于另两个水平（P<0.05）。结论:综合各项指标,在本试验条件下,配制维生素D和钙不同梯度的日粮,通过生长性能、营养物质消化率、氮代谢、钙磷代谢、血清生化等指标,得出当日粮中钙磷比为2:1时,育成期水貂饲粮维生素D水平为4 100 IU/kg,钙水平为3.1%时,水貂能获得较好的生产性能。第二部分:冬毛期水貂饲粮适宜维生素D及钙水平的研究随机选取（135±5）日龄健康短毛黑公貂117只,随机分成9组,每组13个重复,每个重复1只。试验采用3×3双因素随机试验设计,基础饲粮维生素D水平为2 300 IU/kg,钙水平为2.0%,钙磷比固定为1.7:1。设3个维生素D（以维生素D₃形式）添加水平（0 IU/kg、2 000 IU/kg、4 000IU/kg）和3个钙添加水平（0%、0.4%和0.8%）。九组饲粮维生素D和钙水平分别为:Ⅰ组（2 300IU/kg×2.0%）、Ⅱ组（4 300 IU/kg×2.0%）、Ⅲ组（6 300 IU/kg×2.0%）、Ⅳ组（2 300 IU/kg×2.4%）、Ⅴ组（4 300 IU/kg×2.4%）、Ⅵ组（6 300 IU/kg×2.4%）、Ⅶ组（2 300 IU/kg×2.8%）、Ⅷ组（4 300IU/kg×2.8%）、Ⅸ组（6 300 IU/kg×2.8%）,预试期13 d,正试期60 d。结果表明:1)水貂料重比组间存在极显著差异（P<0.01）,Ⅱ组最低。维生素D和钙水平分别对料重比有显著（P<0.05）和极显著的影响（P<0.01）。2)钙水平对脂肪消化率有极显著的影响（P<0.01）,0.8%钙添加水平极显著低于另两个水平（P<0.01）。3)饲粮维生素D和钙水平对水貂氮代谢指标无显著影响（P>0.05）。4)0%钙添加水平极显著降低粪钙、粪磷含量（P<0.01）,提高钙磷消化率（P<0.01）。0² 000IU/kg维生素添加D水平显著提高钙消化率（P<0.05）,极显著降低粪磷含量（P<0.01）,提高磷消化率（P<0.01）。5)维生素D添加水平为2 000 IU/kg时,血清总蛋白浓度显著提高（P<0.05）,甘油三酯浓度显著降低（P<0.05）。钙添加水平为0.8%时,血清高密度脂蛋白浓度显著提高（P<0.05）,低密度脂蛋白浓度极显著降低（P<0.01）。6)钙添加水平为0%时,水貂皮长显著增加（P<0.05）。7)0.8%钙添加水平显著提高水貂心脏指数、肝脏指数、脾脏指数（P<0.05）,0² 000 IU/kg维生素D添加水平极显著提高水貂肾脏指数（P<0.01）。8)当维生素D添加水平为2 000 IU/kg时,水貂十二指肠维生素D受体蛋白和维生素D结合蛋白基因表达量最高。结论:综合各项指标,在本试验条件下,配制维生素D和钙不同梯度的日粮,通过生长性能、营养物质消化率、氮代谢、钙磷代谢、血清生化、脏器指数等指标,得出当日粮中钙磷比为1.7:1时,冬毛期水貂饲粮维生素D水平为2 300⁴ 300 IU/kg,钙水平为2.0%时,水貂能获得较好的生产性能。更多还原

【Abstract】 This study was conducted to study the effects of different dietary vitamin D and calcium levels at a fixed ratio of calcium to phosphorus on production performance of mink in growth period(including growing period and fur-growing period).The purpose is to screen out the suitable level of vitamin D and calcium for mink in growing period and fur-growing period which can provide the theoretical basis for guiding the actual production.The paper consists of two parts:Part 1: Optimum level of vitamin D and calcium in growing minkOne hundred and seventeen healthy male minks at the age of(60±5)days with the similar body weight were randomly divided into 9 groups with 13 replicates each and 1 mink per replicate.Nine experimental diets were formulated by using 3 × 3 double factorial experimental design.The level of vitamin D in basal diet was 2 100 IU/kg and the level of calcium was 2.3% and the ratio of calcium to phosphorus was 2:1.The three supplementary levels of VD were 0 IU/kg,2 000 IU/kg and 4 000 IU/kg respectively;The three supplementary levels of calcium were 0%,0.4% and 0.8% respectively.The vitamin D and calcium in nine experimental diets were group Ⅰ(2 100 IU/kg×2.3%),group Ⅱ(4 100 IU/kg×2.3%),group Ⅲ(6 100 IU/kg×2.3%),group Ⅳ(2 100 IU/kg×2.7%),group Ⅴ(4 100 IU/kg×2.7%),group Ⅵ(6 100 IU/kg×2.7%),group Ⅶ(2 100 IU/kg×3.1%),group Ⅷ(4 100 IU/kg×3.1%),group Ⅸ(6 100 IU/kg×3.1%),respectively.The pretrial lasted for 13 days,and the formal trial lasted for 60 days.The results showed as follows:1)Dietary vitamin D and calcium levels had extremely significant effects on the final weight,average daily gain and F/G(P<0.01),and the final weight and average daily gain was the highest in group Ⅷ,the lowest in group Ⅰ,F/G was just the opposite.2)The fat digestibility in groups Ⅱ,Ⅳ and Ⅴ was extremely significantly higher than those in groups Ⅶ and Ⅷ(P<0.01).The dry matter output of growing mink reached the highest when the dietary calcium supplementary level was 0.8%.The fat digestibility was extremely significantly lower when the dietary supplementary calcium level was 0.8% than that when the dietary calcium supplementary level was 0% and 0.4%(P<0.01).Dry matter output reached the lowest when the dietary vitamin D supplementary level was 2 000 IU/kg.The dry matter digestibility and fat digestibility reached the highest when the dietary vitamin D supplementary level was 2 000 IU/kg.3)Nitrogen retention showed a tendency to increase with the increase of dietary calcium level,and it was the highest at the 0.8% calcium supplementary level.Net protein utilization and protein biological value reached the highest when the dietary vitamin D supplementary level was 2 000 IU/kg.4)Fecal calcium and phosphorus increased with calcium levels(P<0.05).When the supplementary vitamin D level was 2 000 IU/kg,the digestibility of calcium and phosphorus were the highest(P<0.05).5)Serum TP and 25-OH-VD concentration at a VD supplementary level of 2 000 IU/kg was significantly higher than 4 000 IU/kg VD supplementary level(P<0.05).Serum 25-OH-VD concentration at 0% calcium supplementary levels were significantly lower than the other two supplementary levels(P<0.05).Conclusion: Comprehensive analysis of various indicators,under the conditions of this experiment,the diet of VD and calcium with different gradients was prepared.The growth performance,nutrient digestibility,nitrogen metabolism,calcium and phosphorus metabolism,serum biochemistry and other indexes was assayed.The results showed that when the ratio of calcium and phosphorus in the diet was 2:1,the VD level of the diet was 4 100 IU/kg and the calcium level was 3.1%,the growing mink obtained a better production performance.Part 2: Optimum level of vitamin D and calcium in fur-growing minkOne hundred and seventeen healthy male minks at the age of(135±5)days with the similar body weight were randomly divided into 9 groups with 13 replicates each and 1 mink per replicate.Nine experimental diets were formulated by using 3 × 3 double factorial experimental design.The level of vitamin D in basal diet was 2 300 IU/kg,and the level of calcium was 2.0%,the ratio of calcium to phosphorus was 1.7:1.The three supplementary levels of VD were 0 IU/kg、2 000 IU/kg and 4 000 IU/kg respectively;The three levels of calcium were 0%,0.4% and 0.8% respectively.The vitamin D and calcium in nine experimental diets were group Ⅰ(2 300 IU/kg×2.0%),group Ⅱ(4 300 IU/kg×2.0%),group Ⅲ(6 300 IU/kg×2.0%),group Ⅳ(2 300 IU/kg×2.4%),group Ⅴ(4 300 IU/kg×2.4%),group Ⅵ(6 300 IU/kg×2.4%),group Ⅶ(2 300 IU/kg×2.8%),group Ⅷ(4 300 IU/kg×2.8%),group Ⅸ(6 300 IU/kg×2.8%),respectively.The pretrial lasted for 13 days,and the formal trial lasted for 60 days.The results showed as follows:1)There was an extremely significant difference between F/G of mink and the lowest was in group Ⅱ(P<0.01).The calcium levels had a significant effect on the F/G(P<0.05),while the vitamin D levels had an extremely significant effect on the F/G(P<0.01).2)The calcium levels had an extremely significant effect on fat digestibility(P<0.01),0.8% calcium supplementary level was significantly lower than 0% and 0.4% calcium supplementary levels(P<0.01).3)The dietary levels of vitamin D and calcium had no significant effect on nitrogen metabolism index of mink(P>0.05).4)0% calcium supplementary level extremely significantly decreased fecal calcium and fecal phosphorus content(P<0.01),and increased calcium and phosphorus digestibility(P<0.01).Vitamin D supplementary levels of 0~2 000 IU/kg significantly increased calcium digestibility(P<0.05),extremely significantly reduced the fecal phosphorus content(P<0.01)and increased the phosphorus digestibility(P<0.01).5)The serum TP concentration significantly increased(P<0.05)and serum TG concentration significantly decreased(P<0.05)when the vitamin D supplementary level was 2 000 IU/kg.When the calcium supplementary level was 0.8%,the serum HDL concentration of mink significantly increased(P<0.05),and the concentration of LDL extremely significantly decreased(P<0.01).6)When the calcium supplementary level was 0%,the skin length of mink significantly increased(P<0.05).7)0.8% calcium supplementary level significantly increased mink heart index,liver index and spleen index(P<0.05),Vitamin D supplementary level of 0~2 000 IU/kg extremely significantly increased mink kidney index(P<0.01).8)when the vitamin D supplementary level in mink diet was 2 000 IU/kg,the relative expression of VDR and DBP genes in duodenum of mink was the highest.Conclusion: Comprehensive analysis of various indicators,under the conditions of this experiment,the diet of VD and calcium with different gradients was prepared.The growth performance,nutrient digestibility,nitrogen metabolism,calcium and phosphorus metabolism,serum biochemistry,organ index and other indexes was assayed.The results showed that when the ratio of calcium and phosphorus in the diet was 1.7:1,the VD level of diet was 2 300~4 300 IU/kg and the calcium level was 2.0%,the mink during fur-growing period obtained a better production performance.更多还原