Williams R B, Gobbi L
Schering-Plough Animal Health, Breakspear Road South, Harefield, Uxbridge, Middlesex UB9 6LS, UK.
Avian Pathol. 2002 Jun;31(3):253-65. doi: 10.1080/03079450220136567a.
A live attenuated anticoccidial vaccine (Paracox) was compared with a nicarbazin-monensin anticoccidial drug shuttle programme in three crops of Italian broilers, comprising a total of 290,405 chickens. All birds received the antibiotic growth promoter avilamycin. No coccidiosis was evident during the trials, but the occurrence of oocysts in the litter demonstrated that a natural challenge was present. Vaccinated birds consistently performed at least as well as those treated with the anticoccidial drug shuttle. The final mean weights of vaccinated birds were significantly greater (P < 0.001) than those of birds treated with anticoccidial drugs, both for females at 36/37 days and males at 56 days. Feed conversion ratios, total mortality including culls, the proportion of rejects at the processing plant, and the moisture content of the litter were not significantly different between the two control methods. Growth curves showed that there was no post-vaccinal growth check in the vaccinated birds and no intolerance of the anticoccidial drug treatment. There was no overall seasonal effect, regardless of treatment, on the performance of the three crops reared from November 1997 to July 1998. These findings suggest that the use of this vaccine is likely to enable the replacement of anticoccidial drug shuttle programmes in broilers reared under conditions similar to those used in these Italian flocks.
在三组意大利肉鸡中，将一种活的抗球虫疫苗（Paracox）与尼卡巴嗪-莫能菌素抗球虫药穿梭方案进行了比较，三组肉鸡共计290,405只。所有鸡只都接受了抗生素生长促进剂阿维拉霉素。试验期间未发现明显的球虫病，但垫料中卵囊的出现表明存在自然感染。接种疫苗的鸡只表现始终至少与接受抗球虫药穿梭方案治疗的鸡只一样好。在36/37日龄的母鸡和56日龄的公鸡中，接种疫苗的鸡只的最终平均体重均显著高于（P < 0.001）接受抗球虫药治疗的鸡只。两种控制方法之间的饲料转化率、包括淘汰鸡在内的总死亡率、加工厂的拒收比例以及垫料的水分含量均无显著差异。生长曲线表明，接种疫苗的鸡只接种后没有生长停滞，对抗球虫药治疗也没有不耐受情况。从1997年11月至1998年7月饲养的三组肉鸡，无论采用何种处理方式，均未发现总体季节性影响。这些研究结果表明，在与这些意大利鸡群类似的饲养条件下饲养的肉鸡中，使用这种疫苗可能能够替代抗球虫药穿梭方案。
