利福昔明乳房注入剂(干乳期)对奶牛的安全性研究

Study on The Safety of Rifaximin Intramammary Infusion (Dry Period) in Dairy Cows

关键词:  利福昔明乳房注入剂  干乳期  安全性

Key words:  Rifaximin  intramammary infusion (dry  period), Dry  period, Safety

摘要:

【目的】研究利福昔明乳房注入剂(干乳期)对健康奶牛的正常体温、日产奶量、奶中体细胞数和乳房内菌群的影响。【方法】选择健康泌乳期奶牛12头,给药前1 天和给药前0天,统计记录各试验奶牛的直肠温度、日产奶量、检测每个乳区采集奶样的体细胞数,并对给药前0天的奶样进行病原菌分离检测。每头入选奶牛的四个乳区分别单次灌注利福昔明乳房注入剂,在给药后的第1、3、5、7、10 天分别记录每头奶牛的日产奶量；在给药后的第12 小时、3、5、7、10 天分别采集奶样进行体细胞检测,同时检查直肠温度；在给药后的第10 天对采集的奶样进行病原菌检测。比较奶牛用药前后直肠温度、日产奶量、奶中体细胞数和病原菌的变化。试验期间对给药奶牛进行连续观察,记录奶牛是否出现红、肿、热、痛等临床症状。【结果】给药前1 天、给药当天和最后一次给药后的第1、3、5、7、10 天,试验奶牛的日产奶量平均值分别为30.5、30.3、29.8、30.3、30.0、30.9和31.0 kg,相互之间无显著性差异(P＞0.05)；给药前后各时间点采集的奶中体细胞数大都维持在30-50万/mL；给药前后各时间点测得的奶牛直肠温度无显著性差异(P＞0.05)；病原菌检测结果显示,在给药前0天分离到7株大肠杆菌、6株链球菌和9株葡萄球菌,给药后第10 天采集的奶样中未检测到大肠杆菌和葡萄球菌,仅检测到1株链球菌。与给药前相比,奶中的病原菌数量有所减少,无新增感染。【结论】利福昔明乳房注入剂(干乳期)对奶牛正常体温、产奶量、奶中体细胞数无不良影响,该制剂对于奶牛是安全的。

Abstract:

ABSTRACT: [Purpose] This study was to evaluate the effect of rifaximin intramammary infusion (dry period) on cows’ normal body temperature, daily milk output, number of somatic cell count (SCC) in milk and bacteria in udders. [Method] 12 healthy lactating cows were selected, and the rectal temperature, daily milk output and SCC were recorded 1 and 0 day before administration, and the pathogenic bacterias were isolated and detected from the milk samples 0 day before administration. Rifaximin intramammary infusion was injected into four udders of each cow once. The milk production of each cow was recorded on the 1, 3, 5, 7 and 10 d after administration. Milk samples were collected at 12 h, 3, 5, 7 and 10 d after administration for SCC and rectal temperature was recorded simultaneously. On the 10 d after administration, milk samples were collected for pathogen detection. The changes of rectal temperature, daily milk output, SCC and pathogenic bacterias in milk were compared before and after treatment. During the experiment, continuous observation was carried out on the cows to record whether there were red, swelling, heat, pain and other clinical symptoms. [Results] On 1 d before administration, the day of administration and the 1, 3, 5, 7 and 10 d after the administration, the average daily milk production of experimental cows was 30.5, 30.3, 29.8, 30.3, 30.0, 30.9 and 31.0 Kg respectively, there was no significant difference between them (P>0.05); the SCC in milk collected at each time point before and after administration were mostly maintained between 300000-500000 /ml; there was no significant difference in rectal temperature measured at each time point before and after administration (P>0.05); The detection results of pathogenic bacteriashowed that 7 strains of E.coli, 6 strains of Streptococcus and 9 strains of Staphylococcus were isolated 0 d before administration, but no E.coli and Staphylococcus were detected in the milk samples collected 10 d after administration, only 1 strain of Streptococcus was detected. Compared with before administration, the number of pathogenic bacteria in milk decreased and there was no new infection. [Conclusion] Rifaximin intramammary infusion (dry period) has no adverse effects on normal body temperature, milk production and SCC in milk, which is safe for dairy cows.