Survey of equine castration techniques, preferences and outcomes among Australian veterinarians.

This research study aimed to gather information on the methods, preferences, and outcomes of horse castration among Australian veterinarians. The study also aimed to understand how veterinarians use and experience the Henderson castrating instrument, and if there were any links between demographics, castration methods, techniques, and complications.

Methodology

• The study used an online survey to gather responses from members of the Australian Veterinary Association’s Special Interest Group, Equine Veterinarians Australia (EVA).
• Information about the survey was disseminated via the EVA e-newsletter, and veterinary practices featured on the EVA website were directly contacted.
• The researchers used Fisher’s exact test to understand the relationship between ligation (tying off) and complications.
• A generalised linear model with a negative binomial family was applied to discover associations between count response variables and categorical independent variables.

Findings

• The study received 138 responses, equivalent to a 13.1% response rate. These respondents had conducted 5330 castrations over preceding 12 months.
• The results showed castrations were most commonly performed in the field, utilising emasculators, on anesthetized horses, via an open approach, and without ligation of the spermatic cord.
• Use of emasculators reported the following complications: swelling (25%), haemorrhage (5%) and infection (5%).
• About 10% respondents used the Henderson instrument for castration, and its use was associated with fewer reports of postoperative swelling compared to emasculators.
• The rates of evisceration (removal or exposure of internal organs) were similar for both Henderson and emasculator methods (at 0.43% and 0.9%, respectively).

Conclusion

• The study found that the preferences for castration techniques varied among the respondents.
• The study’s reported complication types and rates align with those reported in other countries.
• The data suggests that the use of the Henderson instrument may be associated with less postoperative swelling, which warrants further investigation in a controlled study.