Title: Optimizing Vaccination and Artificial Insemination Protocols to Enhance Health and Reproductive Efficiency of Georgia’s Beef Cattle
Investigators:
Roberto Palomares, DVM, MS, PhD, DACT
Brad Heins, DVM, MFAM, DACVPM
If interested, please contact Dr. Roberto Palomares [email protected] or Dr. Brad Heins [email protected]. Alternatively, you may contact the UGA Large Animal Teaching Hospital at 706-542-3223.
Study description:
The goal of this study is to determine the effects of vaccination at the onset of ovulation synchronization on fertility outcomes in beef cattle. Multivalent vaccination 30 days before the breeding season has proved to effectively prevent fetal infections and pregnancy losses caused by Bovine viral diarrhea virus and Bovine herpes virus 1. Research studies have reported that extra label administration with modified-live virus (MLV) vaccines to BVDV/BHV1-naïve seronegative cattle close to the time of breeding may be associated with reduced fertility; however, other significant field trials have demonstrated that administration of an MLV vaccine concurrent with the onset of the ovulation synchronization protocol (10 days before fixed-time artificial insemination) in seropositive vaccinated cattle did not have any adverse effects on pregnancy or calf outcomes. This approach would allow for better coordination and timing for immunization, optimizing animal movement and reducing animal stress and unnecessary delays, while maintaining adequate fertility in beef cattle herds.
Inclusion criteria:
- Farms with a minimum of 35 healthy female beef cattle
- Body condition score of 6-7 on a 9-point scale
- No clinical or reproductive pathology
- Have history of previous BVDV-BHV1 vaccination and adequate BVDV & BHV1 antibody titers
Cattle will be randomized to 1 of 3 treatment groups involving type and timing of vaccination, and CIDR insertion (for ovulation synchronization). Timed artificial insemination will be performed in all the cows 62 hours after CIDR removal. Pregnancy diagnosis with ultrasound will be done 32 days after timed artificial insemination, with follow up by palpation at 90 days of gestation. During the study, a 10 mL blood sample will be collected from 10% of participating cows at each farm at the following 4 timepoints: 30 days before initiation of vaccination, at the time if CIDR insertion, at artificial insemination, and at time of pregnancy diagnosis. Blood samples will be used to determine BVD/BHV1 titers, and estradiol and progesterone concentrations. Data including pregnancy rates, calving rates, and calves growth performance will be recorded throughout the study.
Benefits to participating farms:
- Free Zoetis’ vaccines and hormones (No-cost; > $35/cow saving)
- Vaccines: CattleMaster GOLD® FP 5 L5 and Bovi-Shield GOLD® FP 5 L5
- Hormones: Factrel®, Eazi-Breed CIDR®, and Lutalyse®
- Free blood sampling and antibody testing (BVDV-1/-2 and BHV-1) on 10 % of animals.
- Genetic improvement by using semen from genetically superior sires (cattlemen’s choice)
- On-farm training and final reports (vaccination and reproductive management)
- Enhanced farm management efficiency: less animal movement and stress, reduced time delays
Producers will cover the costs of veterinary services (farm visits and professional fees) including reproductive exams, insemination, and pregnancy diagnosis at ~30 and ~90 days. Semen straws will also be selected and ordered by the producer.
Duration of study:
The study is currently OPEN and enrolling participants.
Potential benefits to veterinary medicine:
Results of this trial will be essential to prove the idea that vaccination close to the time of breeding does not affect the reproductive ability of beef cattle during the breeding season, and will help tailor novel and more efficient vaccination protocols concurrent with ovulation synchronization to provide fetal protection, while maintaining adequate fertility.
Vaccination concurrent with the initiation of the ovulation synchronization protocol would significantly enhance efficiency (effort and time) during the breeding season. This approach allows for better coordination and timing by optimizing animal movement and reducing animal stress and unnecessary delays, thus streamlining overall herd management.
