Comparative efficacy of BioRelease Deslorelin® injection for induction of ovulation in oestrus mares: a field study.

This research study explores the effectiveness of BioRelease Deslorelin® (BRD) and Ovuplant® in inducing ovulation in female horses, with a particular focus on side effects at the injection site. The results confirmed that both treatments can significantly decrease the time to ovulation, but BRD was associated with far fewer injection site reactions.

Research methodology

• The study was performed on 60 horses (mares) over the course of 95 cycles. The mares’ ovarian follicular activities were monitored using ultrasonography until a follicle ≥30 mm and a specific uterine edema pattern (3) developed.
• The mares were then grouped into three treatment categories: those treated with 1.25 mg BRD, those with a single Ovuplant pellet, and a control group treated with 1 mL compound sodium lactate.
• Ultrasound monitoring of the mares’ follicular activity continued every 12 hours until ovulation was either detected or for at least five days after the treatment.
• The injection site was also monitored for reactions for at least five days post-treatment.

Research findings

• No significant difference was observed in the percentage of mares ovulating within 48 hours after receiving BRD (93.75%) or Ovuplant (87.09%).
• Compared to the control group, treatment with either BRD or Ovuplant decreased the time to ovulation significantly (P < 0.00005).
• The monitoring of the injection sites in mares showed more reactions with Ovuplant (64.5%) compared to BRD (15.6%). No injection site reactions were noted in the control group (0%). This result is also significant (P < 0.00005).

Conclusions

• The findings indicate that treating mares with a 1.25 mg dosage of BRD is as effective in inducing ovulation as treating them with Ovuplant.
• BRD has the added advantage of causing fewer injection site reactions than Ovuplant, making it a possibly safer and more comfortable intervention for the mares.