维生素K3对14日龄北京鸭凝血时间和维生素K依赖蛋白的影响

旨在研究维生素K₃对1~14日龄北京鸭凝血时间和维生素K依赖蛋白的影响，筛选评价肉鸭维生素K营养状况的敏感指标，并得到育雏期北京鸭饲粮维生素K₃适宜添加量。试验采用单因子完全随机试验设计，设6个维生素K₃添加水平（0、0.5、1、2、3和4 mg·kg^-1），通过在玉米-大豆分离蛋白型基础饲粮中添加6个不同添加水平亚硫酸氢钠甲萘醌配制试验饲粮。将180只1日龄健康雄性北京鸭随机分为6个处理组，每处理组5个重复，每重复6只鸭。试验期14 d。结果表明：不同添加水平维生素K₃对1~14日龄北京鸭平均日增重、平均日采食量和料重比等生长性能指标未产生显著影响（P>0.05）。0和0.5 mg·kg^-1维生素K₃添加组凝血酶原时间显著高于2、3、4 mg·kg^-1维生素K₃添加组（P<0.05）。0 mg·kg^-1维生素K₃添加组血清凝血酶原前体蛋白水平显著高于0.5、1、2、3、4 mg·kg^-1维生素K₃添加组（P<0.05）；0 mg·kg^-1维生素K₃添加组血清羧化不全骨钙素水平显著高于2、3、4 mg·kg^-1维生素K₃添加组（P<0.05）。以凝血酶原时间、血清凝血酶原前体蛋白和羧化不全骨钙素为评价指标，采用折线模型估算1~14日龄北京鸭维生素K₃需要量分别为2.00、0.56和1.27 mg·kg^-1。综上，饲粮中添加维生素K₃可增强肉鸭凝血功能，降低血清凝血酶原前体蛋白和羧化不全骨钙素水平。在本试验基础饲粮条件下，以凝血酶原时间为评价指标，采用折线模型估测1~14日龄北京鸭维生素K₃需要量为2.00 mg·kg^-1。

Effects of Vitamin K3 on Coagulation Time and Vitamin K-Dependent Proteins of 14-Day-Old Pekin Ducks

This experiment was conducted to investigate the effects of vitamin K₃ on coagulation time and vitamin K-dependent proteins of 14-day-old Pekin ducks. In order to screen sensitive indicators reflecting the nutritional status of vitamin K in meat ducks, and determine the vitamin K₃ requirements of Pekin ducks. An one-factor completely randomize design with 6 vitamin K₃ supplemental levels (0, 0.5, 1, 2, 3 and 4 mg·kg^-1) was used in this experiment. The diets were formulated by adding 6 different levels of menadione sodium bisulfite to the corn-soybean isolate basal diets. A total of 180 one-day-old male Pekin ducks were randomly divided into 6 groups with 5 replicates each group and 6 ducks per replicate. The experiment lasted for 14 days. The results showed as follows: Different vitamin K₃supplemental levels had no significant effect on the average daily gain, average daily feed intake and ratio of feed to gain of Pekin ducks from 1 to 14 days of age (P>0.05). The prothrombin time of the 0 and 0.5 mg·kg^-1 vitamin K₃ supplemental level groups were significantly higher than those of 2, 3, and 4 mg·kg^-1 vitamin K₃ supplemental level groups (P<0.05). The level of serum PIVKA-Ⅱ content of the 0 mg·kg^-1 vitamin K₃ supplemental level group was significantly higher than those of the 0.5, 1, 2, 3, 4 mg·kg^-1 vitamin K₃ supplemental level groups (P<0.05); The level of serum undercarboxylated osteocalcin content of the 0 mg·kg^-1 vitamin K₃ supplemental group was significantly higher than those of the 2, 3, 4 mg·kg^-1 vitamin K₃ supplemental level groups (P<0.05). Taking prothrombin time, serum PIVKA-Ⅱ and undercarboxylated osteocalcin as evaluation indicators, vitamin K₃ requirements of Pekin ducks from 1 to 14 days of age was determined as 2.00, 0.56 and 1.27 mg·kg^-1 by broken-line regression models. In conclusion, the supplemental of vitamin K₃ to the diet could enhance coagulation performance, decrease the levels of serum vitamin K-dependent proteins such as the PIVKA-Ⅱ and undercarboxylated osteocalcin. Under the condition of this experiment, according to prothrombin time, the evaluation of vitamin K₃ requirements of Pekin ducks from 1 to 14 days of age was 2.00 mg·kg^-1 by broken-line regression models.