A Field Study Assessing Control of Broiler Coccidiosis by Paracox~(TM) Vaccination or by Toltrazuril (Baycox~R) Stand-Alone Treatment

摘要

Toltrazuril (Baycox~R) stand-alone treatment and Paracox-5 (live attenuated vaccine) were assessed in a field trial for broiler coccidiosis control. The feed did not contain coccidiostats or antimicrobial performance enhancers. Fifteen farms encompassing 90 flocks were followed over three trial episodes (Vaccination-1, Toltrazuril and Vaccination-2). Each episode included two successive flocks/grow-outs. Daily weight gain, feed conversion ratio, production number and mortality rate were assessed as performance parameters, indicative of coccidiosis control. No cases of clinical coccidiosis were diagnosed during the course of the trial. In general,there was a wide variability in production number within most of the farms, with only a few showing a more consistent performance. Although descriptive statistics showed small differences between the treatments, an analysis of covariance revealed no significant (P < 0.005) treatment effect on any of the four efficacy parameters. The age at processing and farm significantly affected the feed conversion ratio, daily weight gain and production number, but not mortality. Within treatment groups, the feed conversion ratio and daily weight gain were significantly influenced by the month of hatch. It was concluded that a single treatment with toltrazuril is a valuable alternative to vaccination for coccidiosis control in a rotation programme.