Docking and castrating
Docking is when the tail is shortened. Castration is when the
testicles are removed or destroyed. Both are
routine management practices on most sheep farms in the United States and other developed countries. According to
the last (USDA APHIS) NAHMS Study, 78.6 percent of US sheep operations docked lambs (2010); 81.5 percent of lambs were docked. Three quarters of US operations castrated ram lambs. The average age of castration was 24.7 days.
Docking
Docking improves the health and welfare of sheep and lambs. It
prevents fecal matter from accumulating on the tail and hindquarters
of the animal. Research has shown that tail docking reduces
the risk of fly strike (wool maggots), while having no ill effects on lamb
mortality or production.
Docking facilitates shearing and crutching. It makes it easier to observe the ewe's vulva and udder and detect potential birthing and milking problems.
Some markets (lamb buyers) discriminate against tailed lambs, since having
a tail lowers the dressing percent (yield) of the lamb. On the other hand, ethnic buyers of
lambs often prefer undocked lambs. For the Muslim Festival of
Sacrifice, unblemished lambs are usually preferred.
An unblemished lamb is one that has not been docked, castrated,
or had its horns removed.
At the same time, not all sheep require tail docking. Because hair sheep lambs do
not have long, wooly tails, it is usually not necessary to shorten their tails. Lambs
from the Northern European short-tail breeds also do not require
docking. Fat-tailed sheep are usually not docked. Some producers
of wooled lambs do not dock their lambs or they only dock the
ewe lambs. If lambs are sold at a young age or their hindquarters can be kept clean, it may be possible to leave their tails on, without affecting their health and hygiene. Wooled lambs that go to pasture generally require docking.
Sheep breeds that generally do not require tail docking
Hair sheep |
Short-tailed
sheep |
American Blackbelly
Barbados Blackbelly
Damara
Dorper
Katahdin
Pelibüey
Royal White®
Santa Inês
St. Augustine
St. Croix
West African |
East Friesian
Finnsheep
Gotland
Icelandic
Romanov
Soay
Shetland |
It is natural for a sheep to have a tail. The tail does not interfere with breeding or lambing. The tail protects the ewe's vulva and udder from weather extremes. To some extent, sheep use their tail to scatter their feces. Tail length is the most heritable trait in sheep. A sheep's tail is halfway between the length of its two parents. Scientists are trying to breed wooled sheep with short tails that do not require docking.
Banding
The easiest and most common method of tail docking is to apply
a rubber ring (or band) to the tail using an elastrator or ring extender. Banding
is a bloodless method of tail docking. The band cuts off the
blood supply to the tail, causing the tail to atrophy and fall off in several weeks.
Some producers cut the tail off before it falls off.
Banding causes some pain to the lamb, but the pain is generally short-lived.
Pain varies by lamb and may have to do with placement of the band, on or between vertabrae. Pain can be reduced if a clamp (Burdizzo) is applied across the tail immediately
distal to the ring. The use of a local anesthetic, such as lidocaine,
can be used to reduce the pain felt by the lamb. However, this
is not usually practical as lidocaine is not available for purchase
over-the-counter.
Only veterinarians may prescribe the use of lidocaine. Over-the-counter pain relievers may be available in other countries to producers. There is a new tool called Numnuts® that provides pain relief at the same time it bands. It is unknown if the product will ever be available in the US. The Callicrate Wee Bander™ has been advocated as a more humane method of banding tails, as it utilizes higher tension banding. However, there is no research to support this claim.
Lambs should be at least 24 hours old before bands are applied; otherwise, banding may interfere with bonding and colostrum intake. Bands should only be applied during the lamb's first week
of life. In fact, there is a law in the United Kingdom that restricts
banding to the first week of a lamb's life. Though not mandated, producers in the U.S. and other countries are encouraged to follow this practice.
When bands are used to dock tails, it is very important
that lambs be protected against tetanus (clostridium tetani; lockjaw), as the
rubber ring creates an anaerobic (without oxygen) environment that is favorable
to the tetanus organism.
If the lamb's dam was not vaccinated or her vaccination status
is unknown, the tetanus anti-toxin can be administered at
the time of tail docking. The anti-toxin provides immediate
short-term immunity whereas tetanus toxoid, while longer
lasting, takes 10 days to 2 weeks to elicit any immune response.
Other tail docking methods
An electric docking iron cuts and cauterizes the tail simultaneously
and is probably the most humane method of tail docking. It can
be used on older lambs.
It is more commonly used by larger producers who batch process lambs. An emasculator has both a cutting and crushing mechanism. It can be used for tail docking. The crushing mechanism seals the blood
vessels on the tail remaining on the lamb, while the cutting edge
effectively removes the tail. The emasculator should be left on
the tail for approximately 30 seconds to help prevent bleeding.
A Burdizzo is similar to an emasculator except it does not have
a cutting mechanism. A knife should be used to cut off the tail
(inside the Burdizzo). A "baby" (9 in.) burdizzo should
be used for lambs. It is not recommended that tails be cut off with a knife or scalpel, as this technique can cause excessive bleeding. It is also the most painful method tail docking.
How long?
There is some disagreement with regards to how long the
docked tail should be. In the United Kingdom, it is a law that
the tail stub (dock) be left long enough to cover the ewe's vulva
and ram's anus. Most other countries follow similar practices.
It is a good management practice.
The American Veterinary Medical Association, American Association
of Small Ruminant Practitioners, and American Sheep Industry Association
recommend that tails be removed no shorter than the distal
end of the caudal tail fold. Tails docked shorter than this may
result in an increased incidence of rectal prolapses among lambs
fed concentrate diets. This is because short-tail docking damages
the muscles and nerves used by the lamb's anus.
Ultra-short tail docking may also contribute to the incidence
of vaginal prolapses, though there is no research data to support
this claim. However, New Zealand researchers found that short-docked
ewes suffered higher rates of carcinoma of the vulva. Regardless, there is no justification for ultra-short tail docking for cosmetic reasons.
All lambs should be docked by the time they are 12 weeks old,
regardless of the method used. If older lambs and mature sheep
are to be docked, the procedure should be performed by a veterinarian using general anesthesia.
Though banded lambs are most vulnerable, immunity from tetanus
is recommended for all docking methods.
Castration
The need for castration is varies and is based on the management
needs of the farm and preference of the market place. Ram
lambs grow faster and have better body composition than wether lambs, and when ram lambs
are marketed at a young age (less than 6 months), commercial lamb buyers usually do not discriminate in price. Ethnic lamb buyers
often prefer intact (or entire) males and usually pay a premium for them.
Rams are almost always preferred for the Muslim Festival of Sacrifice.
It is usually not necessary to castrate ram lambs for the freezer (or
locker) trade or when selling lamb directly to consumers, as there is no siginificant difference in the taste or
tenderness of the meat from a young ram lamb versus a wether or
ewe lamb. Older rams may have a slight taste difference and may not be as desirable for direct marketing. On the other hand, some consumers may prefer the taste of a male.
During harvest, it can be more difficult to remove the pelt (skin) from a ram lamb, especially one that has started to develop secondary sex characteristics. Ram lambs are typically dirtier at the time of slaughter. It may be advisable to castrate ram lambs that cannot be marketed by the time they are six months old.
Most importantly, wether lambs are easier to manage and eliminate
the possibilities of early and/or unwanted pregnancies. When ram lambs
are kept intact, it is necessary to wean and separate them from their dams and female pen (or pasture) mates by the time they are 4 months
of age (later for later maturing breeds). If this cannot be done, ram lambs should be castrated.
There are not many producers have not had ewes bred "accidently" by ram lambs.
Male lambs sold for grazing or as pets should be castrated as
they will be easier to manage.
Banding
As with tail docking, there are many techniques that
can be used to castrate ram lambs. The easiest and most common method of castration is the rubber ring or band. Using an elastrator tool (or ring extender), the band is
placed above the testicles, around the neck of the lamb's scrotum. Care should be taken not to place the band over the lamb's rudimentary teats. Banding will cause the
testicles and scrotum to shrivel up and fall off in a few weeks. As with docking, the shriveled scrotum may be removed before it falls off. Both testicles must be below the placement of the band. If one
testicle is missed, it will be retained in the belly cavity,
resulting in a "bucky" lamb that will have male characteristics.
Castration by banding causes some pain to the lamb, but the pain is generally short-lived. Lambs should be castrated at a young age, preferably between 1 and 7 days of age. Castation in the first 24 hours may interfere with bonding and colostrum intake and is not recommended. As with tail docking, pain can be reduced
if a clamp (using Burdizzo) is applied immediately before or after application
of the ring.
Some veterinarians advocate the use of lidocaine
to reduce the pain felt by the lamb; however, lidocaine is not
available for purchase over-the-counter. The new Numnuts® tool provides pain relief at the same time it bands. As with banding tails,
lambs should be protected against tetanus via passive immunity
or use of the tetanus anti-toxin at the time of castration.
Surgical castration
The testicles may be surgically removed. With this method, a sharp knife or scalpel
is used to remove the bottom one-third of the scrotal sac. The
testicles are removed and the wound is allowed to drain and
heal naturally.
Sometimes, people use their teeth to remove the tiny testicles. It is essential that proper aseptic technique be used when the
surgical method of castration is used.
According to research conducted in Great Britain, surgical castration
is the most painful method of castration, as lambs surgically castrated have higher amounts of cortisol in their bloodstream as compared to lambs castrated using other methods. Surgical castration also has the greatest potential for bleeding, infection, and fly infestation (maggots).
Surgical castration should only be done before or after fly season.
Emasculator
A Burdizzo emasculatome is a tool that is used to crush the spermatic
cord, which crushes the blood vessels, thus depriving the testicles
of blood supply and causing them to shrivel up and die. The Burdizzo
does not break the skin. Each cord should be crushed separately.
The cattle-size Burdizzo should not be used to castrate lambs.
The baby Burdizzo should be used.
Other methods
There is an "All-in-One" tool that can be used to
perform surgical castrations. The teeth of the All-in-One tool
are used to grab the testicles after cutting off the bottom
one third of the scrotum with the scissors portion of the tool.
So far, chemical castration has not proven to be effective or
practical.
The Callicrate Bander™ is another option for castration. It utilizes high tension banding and has been advocated for delayed castration. There are also claims that the Callicrate Bander™ is more humane than traditional banding. However, Australian research showed that the Calllicrate "Wee" Bander™ did not reduced pain in 10 week old lambs. In fact, their research showed that it may be more painful early after castration.
Lambs should be castrated by the time they are twelve weeks of
age, regardless of the method used. In the United Kingdom, veterinarians
must perform all castrations in ram lambs over 3 months of age.
Though banded lambs are most vulnerable, immunity from tetanus
is recommended for all castration methods.
Short-scrotum rams
An alternative to castrating is to make short-scrotum ram. A short scrotum ram is a ram whose testicles have been
pushed up into the body cavity and had its scrotum removed. It is the same as a cryptorchid. The band is placed below the testicles. The scrotum will atrophy and fall off.
Less pain is associated with making a short scrotum 'ram' versus
a wether lamb. It is also easier to do. As compared to wether lambs, short scrotum "rams" grow faster and produce leaner carcasses. Though they still retain their testicles, short scrotum rams are usually infertile, because they lack the thermoregulation necessary for spermatogenesis. For spermatogenesis to occur there must be a several degree temperature difference between the testicles and body.
The probability of sterility is increased, if the procedure is performed at a young age (less than 10 days). Low ferility has been observed in short shortum rams that were castrated at older ages. It is important to note that short-scrotum rams will still demonstrate male behavior, as their testicles still produce testosterone, the hormone responsible for male characteristics.
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