For many mixed ( and equine!) practitioners the thought of the castration season can fill vets with an impending sense of doom. There aren’t many of us in the equine industry that can’t tell, or know someone that can tell, a horror story about castrating colts. The areas I practiced in, in England were not areas for large scale breeding, or certainly weren’t in comparison to Ireland, so my exposure to castrating was relatively minimal. In our small two vet practice in Co. Down, we did nearly 60 castrations last season and I hope we’ve continued to tailor our technique into something others may find useful.
I believe the decision-making process starts when you get an understanding of the type of client you are castrating for. Are they experienced and will they be able to offer help? Have they every experienced an equine castration, and could they be more of a hindrance than a help? Do they have adequate facilities and/or space to perform the castration. Will the castration be carried out under standing sedation or general anaesthesia or should the animal be brought to the clinic for the procedure? We are fortunate at Ringneill in having an experienced assistant that accompanies the vets to every castration. This allows us to know each of our roles and makes for a smooth expereince for the patient, client and veterinary team. If you are new to castrating, I think it’s a very good idea to have someone assist you that has experience with castrations.
En route to the farm we usually call the client and request a bucket of warm water and an old towel. On arrival the first decision is location. (I used to conduct all my castrations standing, simply because I didn’t have an assistant with me, in the last year I have decided to do all my castrations under general anaesthesia – I would be hard pressed to ever go back to doing them standing!!) Having made the decision to do the castration under GA look for a large, flat and clean open area on a forgiving surface.
Sand schools or lunge pens are a great surface and can offer fantastic grip for the patient when coming round from anaesthesia. Fields can also be the perfect environment making sure they are not on a hill is essential. Make sure the area you pick is not close to any streams, rivers, fences or hedges as recovery from anaesthesia can be unpredictable.
Often ill-handled, the colt is sedated in the stable then walked out to the surgical site. Sedation with an alpha 2 and an opioid (detomodine and butorphanol) to a level where they become unresponsive to external stimuli (clapping the ear). Before I administer any more drugs I ensure two testicles have descended. I administer the antibiotic, tetanus antitoxin and non-steroidal. Ketamine is then administered to induce. Once administered I then take the colt myself asking all others to stand well back. I encourage the colt into a sitting position by pushing my weight back onto the shoulder with one hand and steering the head with the other. Once on the ground they eyes are covered and within 30 seconds the animal is flipped into dorsal recumbency. It’s much easier at this stage to keep the head and neck out straight for balance. One assistant should now place a leg either side of the neck facing the horses back end with one leg in each hand and balancing one knee on either shoulder of the colt. I always advise the person to keep their head on the midline in case a front leg would kick out. A brief surgical scrub before injecting 15-20mls local anaesthetic directly into each spermatic cord – this makes for less bleeding at surgical site compared to injecting directly into the testicle.
Following a surgical prep myself (I only wear sterile gloves in closed castrations) and the a final prep of the colt I stand directly behind the animal, with each of my knees resting on the inside of either hing leg. Having grasped the testicle in my hand and placing pressure behind it to put tension on the skin, I make a linear incision adjacent to midline. I continue to incise through both layers of tunic until the testicle is exposed. Pressure behind the testicle will encourage extrusion. At this stage I cut the ligament of the tail of the epididymis using my blade to allow separation of the tunic from the testicle.
Once the cremastor and spermatic cord have been stripped back of fasica, the emasulators are applied as close to the skin as possible (nut to nut). This process is then repeated on the other side. After a few minutes the emasculators are removed and cords assessed for any signs of bleeding.
Once happy, I hold the skin incision open and away from the abdomen to allow visualization of the stump as it regresses inguinally. Satisfied there is no bleeding, I use traction on the skin incision to widen the surgical site to allow adequate drainage over the coming days and weeks. In the majority of cases you will have plenty of time to perform the procedure without needing to top up the anaesthesia. The animal is then rolled into lateral recumbency, headcollar removed and towel left over eyes. It is best to leave the animal alone in a quiet space under close observation to recover.
The, now gelding, will usually be up on their feet within 10-30 minutes. I warn the owners the the incision will bleed and is normal as long as drops of blood can be counted. The surgical site will swell and swelling to the size of the testicles is acceptable. I advise there shouldn’t be anything ever dangling from the surgical site. I always aim to castrate in the morning in case any complications to occur to give me time to deal with them. I always keep my phone close to hand for any queries that may arise. The animals are best turned out 24 hours after castrating and encouraged (chased if needed) to have 15 minutes exercise at a trot daily, to encourage the surgical site to remain open and drain. Finally, owners are advised to keep geldings away from mares for 6 weeks.
Chris graduated from The University of Nottingham in 2013. Following graduation he completed an equine internship at Oakham Equine Hospital. Following his year at Oakham Chris moved to a position as an ambulatory vet at Rossdales Hertferdshire. Chris later re-joined the ream at Okaham with both ambulatory and hospital based roles. Chris later practiced at Tullyraine Equine Clinic, Co. Down, where he further developed his interest and experience in lameness and poor performance. Chris is an accredited FEI treating vet, and has experiene working at the races both at Down Royal and Downpatrick racecourses. In April 2019 Chris became a partner at Ringneill Equine Clinic, Co. Down, where they have made significant advances locally through investment in multiple new imaging modalities including digital readiography and gastroscopy. The work undertaken at Ringneill ranges from race duties, to pleasure ponies and Olympic dressage and event riders.