雌性水貂准备配种期日粮适宜脂肪水平的研究

为探讨水貂准备配种期日粮脂肪水平对日粮中营养物质消化率和水貂氮代谢的影响,确定水貂准备配种期日粮适宜脂肪水平。试验选取体重相近的健康母貂120只,随机分成4组,每组30只,分别饲喂以黄花鱼、膨化玉米和动物下脚料等配制的鲜全价饲料。饲粮蛋白质水平相同,为34%,脂肪水平分别为日粮干物质的8%、12%、16%和20%,试验从12月初至配种前,试验中期进行水貂消化代谢试验。结果表明:日粮脂肪水平对水貂干物质消化率和蛋白质消化率影响差异不显著(P>0.05),日粮脂肪水平对日粮中脂肪的消化率有极显著的影响(P<0.01),随着脂肪水平的增加,脂肪消化率有增加的趋势。准备配种期当日粮脂肪水平达到12%以上时,水貂的日采食量,日氮食入量和氮沉积极显著降低(P<0.01),当日粮脂肪水平为8%时,水貂的采食量与日粮脂肪水平为12%组差异不显著(P>0.05),蛋白质消化率、氮食入量、氮沉积都显著高于其他脂肪水平日粮组(P<0.01),同时粪氮和尿氮排出量与其他脂肪组差异不显著(P>0.05)。综合以上指标,考虑节能环保,并能有效提高水貂饲料利用率,减少饲料成本,得出准备配种期水貂日粮脂肪水平为8%即可满足水貂的生产需要。

Evaluation of Different Dietary Fat Levels on Preparative Mating Female Minks

The experiment was conducted to evaluate the regularity of digestibility and metabolism of diets with different fat levels of female minks on preparative mating period,and to determine the prime fat level of diet.120 healthy female minks with same body weight were randomly assigned into four groups with 30 replicates each.The treatments were individually fed fresh diets with 8%,12%,16% and 20% fat levels,the protein level of diets were 34%.The main ingredients of diets were corvina,extrusion corn,animal offal etc.The trial was carried out from early February to the date before mating,the balance experiment of minks were started during the middle experimental period.The results showed that the fat level of diets did not affect the digestibility of dry matter and protein(P>0.05),but the digestibility of fat was influenced with different dietary fat level(P<0.01),and the digestibility of fat was increased by the dietary fat level increasing.When the dietary fat level reached to 12% of diets,the daily feed intake,daily nitrogen intake and nitrogen retention of minks significantly reduced(P<0.01).Daily feed intake was no significant difference between 8% and 12% fat level treatments(P>0.05),digestibility of protein,nitrogen intake and nitrogen retention of 8% fat level treatment were significantly higher than those in the other groups(P<0.01),but the urine nitrogen and feces nitrogen were similar among all groups(P>0.05).Considering all the factors,the level of dietary fat should be about 8% of diet to meet the requirements of preparative mating minks,furthermore,the 8% fat level of diets for minks would be benefit in terms of reducing feed expenses and improving the feed utilization rate.