Castration is a broad word that is almost known by everyone and also the activity is more common even in the many years back before civilization it was practiced. It is a common procedure which involves the destruction or removal of the testicles to stop reproduction or production of male hormones. The procedure is done either by crushing or excision. Castration is an important management practice for sheep and goat farmers to maintain control of their breeding program and successfully carry out breed improvement. Castration is the removal or destruction of the testes, epididymis and a portion of each spermatic cord from a ram/buck. In most cases, non-breeding males and males not slaughtered at a young age should be castrated. Traditionally, farmers do not castrate animals and both males and females are allowed to run together. The result is that inferior males mate with females passing on undesirable traits and the young stock produced are not very productive
Why castrate sheep and goats?
- Reduced sexual activity.
- Less likely to fight, reducing bruising and injuries to themselves and other sheep. Also allowing other husbandry practices (e.g. shearing) to be undertaken more quickly, efficiently and safely.
- Easier to keep in paddocks after the time that sexual maturity would be reached. Hence prevention of unwanted mating and pregnancies, particularly with the risk of dystocia in maiden ewes.
- Allows for management flexibility to finish lambs to meet market specifications under variable seasonal conditions.
- Wethers grow a finer wool quality than rams.
- Ease and efficiency of processing (significant increase in the cost to producer for the processing of entire males).
- Improved meat quality in sheep.
- Prevent breeding of related individuals (inbreeding) that can result in genetic defects, poor growth rate, and other problems.
- Enhance on-farm safety for animals, producers and employees. Castrated animals are usually less aggressive and easier to manage.
- Reduce goaty smell: meat from castrated males has less ‘goaty smell’ or tainted odor in the meat from intact bucks.
- Carcass composition and weight development. This is one of the main effects of castration. In general the following effects are noted:
- carcasses from castrated sheep/goats have more fat tissue
- castration could retard growth and reduce the quantity of lean meat if done late (after 6 months of age).
Guidelines for Castration
Since the consideration of animal rights there are some guidelines which have been put in place to control or guide the castration process so that animal cruelty is avoided. The following are a few of the guidelines:
- Lambs destined for slaughter before 12 weeks old, or the onset of puberty, should not be castrated.
- Castration should be done after a secure maternal bond has been established, and after the lambs are 24 hours old.
- Lambs should be castrated or made crypt orchid as young as possible and before they are 12 weeks old.
- Castration should be planned with consideration to the age of lambs, weather, staff availability and facilities, including the use of temporary or permanent yards.
- Good hygiene practices should be practised in relation to facilities, hands, handling and instruments. Disinfectant should be used and changed frequently.
- Infection should be minimised by avoiding muddy or dusty yards, and wet or humid weather. Operators should adopt appropriate strategies to minimise the risk and impact of common infections such as Clostridium Tetani through vaccination of lambs and/or their mothers. Lambs should be appropriately restrained in a lamb cradle and, when released, should land on their feet to avoid contact of the wound(s) with the ground.
- Lambs should be separated from their mothers for the shortest possible time.
- Haemorrhage should be minimised by selecting an appropriate method, preventing overheating of lambs and allowing them to settle after mustering.
- Castration should not be undertaken during extreme weather.
- Castration should be done when fly activity is minimal, or in conjunction with appropriate preventive fly strike treatment.
- Sheep should be inspected regularly and with minimal disturbance for signs of post-operative complications during the healing process, and appropriate action taken.
- Castration should be accompanied by pain relief when practical and cost-effective methods become available. Operators should seek advice on current pain minimisation strategies.
- Ewes should be managed to optimise milk production to maximize protein availability for the lamb to aid wound healing.
- After placement in paddocks, lambs should not be forcibly mustered and yarded until wounds are healed.
Age of castrating sheep and goats
Castration should take place at the youngest age possible since the stress of castration can adversely affect growth in older animals. Lambs/kids can be castrated as soon as the testicles descend into the scrotum (this can be from a few days of age to three weeks) and no sedation or pain killers are necessary if castration is done at this age. Castration becomes more difficult and painful with age and the chances of complications increase. Further, castration is accomplished more easily and the wound heals more quickly in very young animals. Castration should ideally be done at less than 3 weeks of age. Some farmers prefer to castrate male sheep/goats at a later age; in most cases after sexual maturity is attained (yearling to 2 years old). The reason given for this is that early castration can cause stunted growth, resulting in a lack of desired muscling and conformation, leading to a low market price.
Methods of Castration
There are three methods which are commonly used for castration for sheep/goats. The Burdizzo method, the banding or elastrator method and the knife (surgical) method but this article will cover only the first 2. The different methods are more suitable for different sizes and age of animals. It is good to match castration method to size and age of animal.
- The Burdizzo (Emasculatome) method
The Burdizzo is an instrument used to crush the spermatic cords and associated blood vessels thus destroying the blood supply for the testes. Without this blood supply, the testicles degenerate and atrophy. This method is known as a “bloodless” method since no cutting is done and when done properly even the skin is not broken. While no castration method is completely painless, the least painful is the Burdizzo method. Castration with this method can be done at any time; but when done at a later age, it may bring about a temporary shock in growth. This is the recommended method for castration by non-health professionals.
The Burdizzo must be in good condition to be a in use. The jaws must be parallel and close uniformly across their width so pressure will be evenly distributed. Keep the Burdizzo clean and oiled. Leave it slightly open when not in use. There are Burdizzos for animals of different sizes. Use the right size of burdizzo for sheep and goats. The use of burdizzos meant for cattle can tear the scrotal tissue and cause undesirable wounds.
How to perform castration using a burdizzo
- Step 1. The animal should be properly restrained by the assistant. The operator grasps the scrotum in one hand and manipulates the testes down into the scrotum. He then locates the two spermatic cords between the fingers and pushes one cord over to one side of the scrotum. This is the first cord to be crushed.
- Step 2. Place the jaws of the burdizzo onto the upper scrotum, leaving the rudimentary teats above the crushing point. Do not crush the septum or tissue between the testicles. Rather, do one side of the scrotum at a time.
- Step 3. Clamp the burdizzo over the cord on the side of the scrotum you are doing first. You cun generally hear a clicking sound as the cord is crushed. Leave the instrument closed for 20 to 25 seconds or the time it takes to count from one to 25. The spermatic cord is very elusive when you try to crush it. Be sure that you feel it within the jaws of the burdizzo before and after the jaws are closed. You can tug on the cord to see if it feels ruptured.
- Step 4. Release the Burdizzo, move it lower to a new site about 1 cm closer to the testicles and close it again to be doubly sure that the cord is crushed. A site below the first crush is chosen to minimize acute pain from a second crush.
- Step 5. Locate the cord on the other side of the scrotum and position the burdizzo over it. Close the burdizzo and repeat what you did with the first cord.
- Step 6. When you are done, you may see a mark on each side of the scrotum. The animal may be sore and move slowly for about a day. Be sure to encourage it to move around. At first the scrotum will swell up a little, but the testicles will gradually shrink over the next few weeks leaving a small scrotal sac. Even though this is supposed to be a bloodless method, it is possible to break skin with the corners of the burdizzo. Examine each crushed area carefully after castration. If the skin is broken, apply an antiseptic like alcohol. Also give an injection of tetanus antitoxin if available.
- The banding or elastrator method
This method involves cutting off the blood supply to the testicles with a heavy-duty rubber band or ring. Materials needed include an elastrator and castrating bands. An elastrator is a special applicator that stretches a heavy-duty rubber band and applies it to the neck of the scrotum. The scrotum and testes will fall off in two to 4 weeks, depending on the size of the testicles. This method is most effective for young animals whose scrotal tissues have not yet become well developed, preferably while they are 7 to 10 days of age and definitely before 6 weeks old. This is an easy method of castration provided a continuous supply of rings is available.
When using the band for castrating, be sure to check that both testicles are in the scrotum below the band. Animals castrated by this method will have a female-like appearance because of early castration. One caution in the use of this method is the potential for tetanus to occur prior to the scrotum falling off. The risk increases with increasing age of animals castrated. This method causes some stress to the animal due to the pain and discomfort experienced by the constricting band, especially for 10 to 15 minutes after the elastrator band is applied.
How to castrate lambs/kids using the elastrator method:
- Do not use rings older than 12 months to avoid breakage and to assure a tight fit. The rings must be strong enough to cut off blood flow in the arteries as well as the veins. If not, the scrotum will swell.
- Place a rubber ring over the prongs of the elastrator. Hold the elastrator with the prongs facing up. Close the handles to open the band.
- The scrotum and testicles are then passed through the expanded hole of the band. Position it as close to the animal’s body as possible with care taken not to place the band over the rudimentary teats or involve the penis.
- Release the elastrators displacing the ring from the prongs, thereby positioning the band.
- The band will return to its original shape cutting off circulation to the testicles and eventually causing all of the tissue below the band to die and fall off.
- Check to be sure both testicles are still in the tip of the scrotum and that the ring is placed properly. If not, cut the ring with scissors and repeat the procedure.
- Administer an injection of tetanus antitoxin. Even though this is a bloodless procedure, the tetanus organism can gain entry through the irritated tissue around the rubber ring.
- Check daily to be sure that the rubber band is still around the neck of the scrotum and for signs of infection.