Abstract
The aim of this study was to evaluate the duration of estrus suppression after a double administration of the anti-GnRH vaccine Improvac® (Zoetis Schweiz GmbH, 2800 Delémont) in cows. Furthermore, it should be investigated, if a third administration could prolong the effect of the cycle suppression. A total of 21 cows (more than four weeks post partum) were vaccinated twice, at least 35 days apart, with 2 ml Improvac® (0.4 mg of a GnRH-analogon) subcutaneously on one side of the neck. Over a period of 368 days and in the course of 18farm visits these cows were examined gynecologically and re-vaccinated if they showed signs of estrus behaviour or ovarian activity. After the second vaccination the cycle of the cows was suppressed for an average period of 114 days (59-175 days) and the effect could be prolonged by a booster of the vaccine for another 127days in three cows. Estrus behaviour was absent for a longer period than ovarian activity was. The vaccine was tolerated well: apart from slight swelling at the injection site, no side effects were observed. Our results demonstrate that two immunizations with Improvac® are an easily applicable method for the suppression of cyclic activity in cows for a mean period of 114 days. The duration of cycle suppression was prolonged by a booster of the vaccination.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.