Castration is any procedure in which the testicles of a male animal are removed. The testicles of a calf produce sperm, along with hormones affecting growth and behavior. Castration has been used for centuries in domestic animals.
Calves are castrated because steers (male calves that have been castrated) have many desirable characteristics compared to bulls (male calves that aren't castrated). Steers do not grow as large and muscular as do bulls. Steers are safer to have around compared to bulls. Bulls are more likely to fight other cattle or attack people. Bulls that fight other cattle can cause broken bones and other injuries, resulting in pain and suffering in those animals. Bulls are more likely to show aggression towards people that can result in injuries and deaths. Bulls of dairy breeds are especially dangerous, as they are raised around people and do not fear them.
The meat that comes from steers is also quite different compared to meat from bulls. In general, bulls have more muscle tissue and less fat. The meat from bulls is tougher and not as pleasant for people to eat compared to meat from steers.
It is necessary to keep some bulls for breeding purposes, but it is not a good idea for all male cattle to be able to reproduce. Bulls that have the ability to pass along birth defects, some of which may result in suffering or death of the calf or its mother, need to be castrated so these conditions do not occur. Some bulls father calves that may be too large for a cow to give birth to on her own, the result of which could be a stressful, painful assisted calving, or a caesarean section.
There are two ways to castrate calves: surgical removal or stopping the blood flow to the testicles.
Surgical removal involves making a cut in the calf's scrotum (the skin surrounding the testicles) and physically removing the testicles. These organs have a significant blood supply andcare is taken to assure there is not excessive bleeding. Control of bleeding is accomplished by the surgeon crimping the cord (the structure that suspends the testicles and provides a blood supply) with a special tool, or by stretching the cord during testicle removal, which tapers the blood vessels such that external bleeding is not excessive.
The advantage to surgical removal compared to other methods is that the operation is quick and immediate, and the calf can start the healing process right away. However when using surgical castration, an open wound is created which may allow contamination and infection into the area. Other disadvantages of surgical castration include the pain that the calf experiences from the incision and testicle removal and potential severe blood loss that can result in weakness and possibly death. The process of surgical castration also presents a possible safety hazard to the surgeon as sharp surgical knives are used in the procedure.
Castration by stopping the blood flow to the testicles is usually accomplished by means of placing a tight rubber band above the scrotum. The band squeezes off the blood vessels, and all of the tissue below the band dies and eventually falls off. The advantages of banding include no blood loss, lower risk of infection, and greater safety for the operator.
Disadvantages of banding include pain for a short duration because as the tissue loses its blood supply, the nerves do too. Also, there is an area of persistent irritation above the band until the scrotum falls off and healing is complete. While bands are on the calf, research indicates that calves experience decreased feeding, walking, and weight gains, likely due to low-grade irritation from the band. The healing process can take a long period of time, six weeks or longer in bigger bulls. Banded calves are typically more susceptible to tetanus infections as well.
Calves may be castrated anytime in their lives, but the procedure needs to be done before the calves approach puberty. Usually cattle raisers castrate calves when they are young. In order to make the best use of time and help, castration is typically performed at a time when other procedures are performed. Sometimes this is done soon after birth on a calf-by-calf basis, when new calves are first tagged for identification. More commonly, an entire herd or group is castrated at once, along with vaccination, branding, or other procedures, to make good use of available help. This also minimizes the time associated with gathering and confining the herd, and the time calves are separated from their mothers for the procedures. This generally occurs before calves and their mothers are turned out to pastures and calves are 2-3 months of age or younger; or later on as cattle raisers prepare their calves for weaning and removal from summer pastures.
There are advantages for castrating calves at as young of an age as possible. Calves are easier and safer to handle. The procedures involve less tissue to remove, cut through, or fall off, and blood supplies are not as developed. This means fewer instances of complications due to infection or blood loss. Younger calves appear to be more resilient than older bulls as they heal. If the cattle raiser is supplying bulls for future breeding, it is sometimes necessary to delay the decision to castrate a bull in order to give the calf extra time to grow and demonstrate whether he will be worthy of passing on his genetics.
Anesthesia can be local in nature, in which the calf remains awake but the parts of the body that are worked on are numb and the animal does not feel pain associated with those areas, or general in nature, in which the calf is made to sleep during the procedure.
Local anesthesia can be performed by injecting anesthetic substances into the scrotum and testicles, numbing that area only, or by injecting anesthetic substances into the rear part of the spinal canal (also known as an epidural), numbing the rear portion of the calf. Administering an epidural to a calf requires technical skill. Both of these techniques are effective at preventing the calf from reacting to castration in a painful way. Both require that several minutes pass before the anesthetic is effective.
Since performing any procedure on calves requires calves being temporarily confined and separated from their mothers—which is stressful for calves—cattle raisers attempt to minimize this time interval. In most cases, the time spent waiting for anesthetic to take effect would at least double or triple the time the animal is confined and away from the other animals. Local anesthesia is not currently utilized for calf castration primarily due to this reason, in addition to the increased workload the waiting period places on the people helping process the animals.
Administering local anesthetic is not without pain itself, as needles are used to inject the anesthetic into the animal, although much likely less pain than that of castration. There are no anesthetics available that work by simply applying to the skin of cattle. Local anesthetics have a limited length of action, normally several hours, so they do not afford long-term pain relief. Although rare, epidural anesthesia can result in complications like infection and paralysis.
General anesthetics are available for cattle, but are not practical for quick procedures such as castration. They take a long time to start working and need to be precisely dosed according to the weight of the calf. Current general anesthetics used result in a calf sleeping for periods of 30-60 minutes following administration, during which time the calf is more prone to complications due to overdosing, chilling, or overheating. The calf is severely uncoordinated as it recovers, making it prone to injury. For these reasons, general anesthesia for this type of procedure creates more potential well-being problems for the calf than it solves.