重组溶葡萄球菌酶对奶牛乳房炎的疗效研究

Therapeutic Efficacy of Recombinant Lysostaphin on Bovine Mastitis

关键词:  重组溶葡萄球菌酶  奶牛  临床乳房炎  隐性乳房炎  疗效

Key words:  recombinant lysostaphin  dairy cow  clinical mastitis  subclinical mastitis  therapeutic efficacy

摘要:

以85头患乳房炎奶牛共104个乳区为研究对象，随机分为4组，每组26个，分别用重组溶葡萄球菌酶粉低（200U/乳区）、中（400U/乳区）、高（800U/乳区）三个剂量，对照组为青霉素G钠（160万IU /乳区），每天早晚挤奶后乳房内注入给药,共4天，研究不同剂量重组溶葡萄球菌酶对奶牛乳房炎的治疗效果。试验结果显示低、中、高剂量重组溶葡萄球菌酶均能有效清除感染乳区的链球菌、葡萄球菌、化脓隐秘杆菌等G 菌，大幅降低牛奶中的体细胞数，提高了奶牛的日产奶量。其中低剂量对隐性乳腺炎、临床型乳房炎的有效率和治愈率略优于青霉素G钠（P＞0.05），中、高剂量对隐性乳腺炎、临床型乳房炎的有效率和治愈率显著优于青霉素G钠（P<0.05），中、高剂量的疗效相当（P＞0.05）。因此，重组溶葡萄球菌酶是一种很好的治疗奶牛隐性乳房炎和临床乳房炎药物。

Abstract:

To investigate the therapeutic efficacy of administrating different dosage of recombinant lysostaphin (rLysostaphin) for bovine mastitis during lactation, 104 udder quarters selected from 85 cows of mastitis were randomly assigned to 4 groups. Each group included 26 udder quarters. Three treatment groups (Group I, Group II and Grouop III) were treated with intramammary rLysostaphin infusion of low, middle and high dosage twice daily for 4 days. The low, middle and high dosage were 200, 400 and 800 U rLysostaphin / Udder quarter respectively. The last group was treated with intramammary penicillin G sodium infusion (Group IV: 1,600,000 IU /Udder quarter of penicillin G sodium) as control. The results showed that the low, middle and high dosage of rLysostaphin effectively eradicated gram-positive pathogens such as Streptococci, Staphylococcus and Arcanobacterium pyogenes from infected udder quarters, decreased somatic cell count of milk secreted from infected udder quarters and increased daily milk yield. The effective rate and cure rate of low dosage (Group I) was higher than that of control group (P >0.05). The effective rate and cure rate of middle and high dosage (Group II and Group III) was significant higher than that of control group (P<0.05). The therapeutic effect of Group II and Group III was comparative (P>0.05). In conclusion, the rLysostaphin showed its high efficacy in the treatment of bovine mastitis caused by Staphylococcus and Streptococcus.