Showing posts with label tail docking. Show all posts
Showing posts with label tail docking. Show all posts

October 10, 2011

Sheep husbandry - docking lambs' tails

By Dr Clive Dalton


Docking lambs' tails
R
emoving lambs' tails has been a standard part of sheep husbandry from early times, mainly to prevent the formation of soiled wool or 'dags' sticking to the wool of sheep eating lush pasture. Removing soiled wool or dagging has always been one of the least popular jobs on a sheep farm.

Hill and mountain sheep in Britain for example, and sheep in dry desert areas do not need docking, as their normal diet is made up of dry herbage which does not produce soft faeces which then stick to the wool around the britch.

The other important reason for not docking hill and mountain sheep breeds in cold climates is that the tail protects the udder and rear end and is a said to be a source of fat which the sheep can use in times of poor nutrition.

It is done for these reasons:
  • First to prevent blowflies laying their eggs among the dung and the maggots hatching out and eating into the sheep's flesh. In the worst cases flyblown sheep can die very quickly.
  • Lambs sucking daggy ewes get dung on their heads and this makes them prone to blowfly attack.
  • To prevent the soiled wool from contaminating the clean wool of the sheep with green dung stain which then costs money to scour out.
  • The NZ Shearer's Union requires all sheep put up for shearing to have been dagged. This is to prevent shearers picking up bacterial diseases such as campylobacter and salmonella from the dung.
  • For cosmetic reasons - there's nothing worse than looking at a flock of sheep with rear ends caked with dags.
Consumer concerns
An ever increasing number of people these days think food comes from supermarkets. They have no reason to believe anything else, as they are totally ignorant of what goes on in the production end of the agricultural or horticulture industry.

But they are concerned about animal welfare issues, which they learn about via television - usually when there is a crisis which has good media attraction. The docking of lambs' tails is one of those issues, highlighted by an inquiry I had from a researcher at a major UK supermarket chain, about the tails of New Zealand lambs being too short and causing concern.

NZ Code of Welfare:

Fortunately in New Zealand we’re well covered in the new Animal Welfare (Painful Husbandry Procedures) Code of Welfare 2005 as part of the Animal Welfare Act 1999. Here’s some key points from it.


Minimum Standard No. 4 – Tail docking of sheep

(a) Tail docking of sheep must only be undertaken where there is significant risk of faecal and urine contamination, and/or flystrike, that leads to poor hygiene, health and welfare and/or failing to do so adds a significant cost to the system.

(b) While complying with Minimum Standard 2(a), tail docking without pain relief must be performed when sheep are as young as possible, and not greater than six months of age.

(c). When tail docking a sheep over the age of six months, pain relief must be used.


Minimum Standard 2a says that:

‘Painful procedures must not be performed on newborn animals less than 12 hours old where handling, pain and post-operative complications are likely to compromise survival through impairing maternal bonding and/or colostrum intake.’

Minimum Standards will stand up in a court of law but the Codes also have ‘Recommended Best Practice’ which do not have the legal power of a Minimum Standard. But they are meant to be followed as part of ‘Best Practice’.


Recommended Minimum Standard

For tail docking of lambs, the Recommended Minimum Standard says that ‘when sheep are tail docked, their tails (excluding any wool) should be left long enough to cover the vulva in females and at a similar length in males.’


Why Kiwis dock too short?

If you have ever been in a docking gang on a big farm, you know why. When lambs are coming at you at great speed, you have to hit the right spot on the tail with the hot cauterising iron or the ring pliers without delay. You are not allowed much time to decide which is the correct spot. The greater concern is that you may leave the tail too long, (which will upset shearers later on), rather than dock the lamb too short.


Consumers's concerns must be recognised

But from now on ‘getting it right’ has become an important priority from what folk are thinking and clearly dictating as they push their trolleys around the supermarkets of the world.


It’s no good us thinking shoppers don’t know anything about sheep farming. They don’t. But this is no reason to ignore the messages about buying lamb they are sending via the supermarket checkout.


Stud breeders

These in my view are the worst offenders at docking too short, as it seems that a very short dock, or none at all does a better job of showing off a ram’s meaty rear end.


Damage caused by short docking

Short docking damages the tissues around the anus and can affect the sheep’s ability to defaecate properly hence causing more dags. A lambs tail needs to be long enough to wag!


Lamb tail docks
In your photos you can clearly see the caudal folds with ligaments that run alongside the anus and under the rectum, so when the tail is lifted the rectum is lifted and poo (even runny poo) is directed away from the body. Short tails can't do that and the poo slitters down the back end.

What is the correct length?

Tail ring in correct position on female lamb's tail.
The dock should be long enough to cover the vulva.

Tail ring in correct position on male lamb's tail.
It dock should be a similar length as in the female.





January 2, 2009

Sheep Farm Husbandry - Castration and Tail Docking


Castration, tail docking, age, methods, welfare issues

By Dr Clive Dalton

These procedures have been carried out for centuries, castration to reduce the number of males on the farm, and docking tails to avoid the growth of dags that attract blowflies. So the term “docking” for both these operations, done at the same time.

Both involve animal welfare issues as they are done by farmers (and not by veterinarians), and no anaesthetics are used

Castration
At what age?
  • Ram lambs grow much faster and are leaner than castrates (wethers) and so make more money in the meat trade. So don’t castrate them if you don’t need to and if you have a good market for them.
  • On large farms the risks of stray ram lambs disappearing and turning up again to mate ewes before they are discovered is a real one, so castrating all unwanted males is sound management.
  • It’s recommended that castration should be done after maternal bonding has been completed (i.e. 12-24 hours) and before 6 weeks of age.
  • Under current law it is an offence to castrate any sheep over 9 months old unless it is done by a veterinarian who will use some form of anaesthetic.
Methods
Rubber rings
  • Using rubber rings is the most humane method.
  • A ring is stretched with special pliers and placed around the neck of the scrotum.
  • The rule is simple – make sure that before the ring is released that both testicles are below the ring and the rudimentary teats are above it.
  • Hold the testicles down with your free hand in the scrotum while you release the ring to make sure they don’t escape back above the ring.
  • It’s best to do the lambs between 7-10 days old.
  • Lambs feel pain as judged by them lying down and kicking from 5-15 minutes but then they show no more obvious distress.
Two nicely docked lambs. Tails will drop off in about 10 days. They are marked on the tail to help check on mothering up
Knife
  • This used to be the standard method before rubber rings were invented.
  • It is not recommended now because it’s slow and the risks of infection, bleeding from the wound, hernias and blowfly attack is very possible.
  • The bottom of the scrotum is cut with a sharp knife or scalpel and the testicles pulled out or “drawn”.
  • They are slippery and hard to hold and pull out. Old shepherds used to draw them with their teeth!
  • Research has shown it is much more painful than the rubber ring method.
  • Surgical castration should only be done by a veterinarian using pain control.

Emasculator pliers
  • These pliers (called the Burdizzo emasculatome) crush the spermatic cords making the ram infertile.
  • They are slow and clumsy and are not used much now.
  • There is always doubt about the result too as you cannot see the end result of the action.
The cryptorchid procedure
  • This is also called the “short scrotum method” and is where a rubber ring is put around the scrotum so it will eventually drop off, leaving the testicles up against the body wall.
  • The higher temperature this creates makes the sperm infertile while the ram gets the growth benefit of the male hormones while being infertile.
  • Be warned though – an odd cryptorchid may not be completely infertile and may be able to get females pregnant.

Tail docking
At what age?
  • The minimum standard says tail docking must only be done if there is a significant risk of faecal or urine contamination, or blowfly strike that will lead to poor hygiene and health. So if you cannot justify it – then don’t do it.
  • Without pain relief - dock lambs as young as possible, and not older than 6 months of age.
  • Beyond 6 months you must use pain relief which may mean the costs of a veterinarian.
  • Generally docking should be done after maternal bonding has been completed (i.e. 12-24 hours). But some farmers dock with rubber rings when tagging the lambs and claim it does not affect bonding.

What length to leave the dock?


  • The tail dock (the bit left) should be long enough to wag!
  • A good guide is that the dock should cover the vulva of a ewe lamb and be the equivalent length in males down to the bald bit on the underside of the tail. This is clearly stated in the MAF Sheep Code of Practice.
  • If the lamb is able to raise it’s dock when defaecating, it lifts the supporting tissue around the anus (the caudal folds) so can direct any diarrhoea which is common on New Zealand pastures away from the body.
  • If the dock is too short, the dung runs down its legs and into it’s crutch.
  • Leave the tail on any ram lamb that you cannot locate the testicles – it’s a good visual sign when drafting. It’s a ‘long tailer” and hence a cull.
This ram's tail dock is far too short, and you can see
the damage done to the tail ligaments. The
MAF Sheep Code of Welfare has been ignored

Methods
Rubber rings
  • Use rubber rings when lambs are 7-10 days old, and the tail should drop off 10-14 days later.
  • Don’t cut the tail off below the ring as the blood can attract blowflies.
  • Check the scar on the tail stump incase it has gone septic and attracts blowflies. This does not often happen.
Cauterisation
  • Here a gas-heated iron is used to both cut and cauterise the tail in one action.
  • Correct pressure on the iron is important to make sure the stump has been cauterised during the cutting action. A steady slow action is needed.
  • You soon learn to get it right if you have to hold a bleeding tail stump between your fingers, and cauterise it with the hot iron while the lamb is kicking with the pain!
  • Check that no docks are bleeding before returning lambs to their mothers. Any that are bleeding will have to be re cauterised.
  • Blowfly repellant can be applied to the dock if flystrike is a problem.
  • Don’t dip the lamb’s backside in a drum of sheep dip as the fluid rapidly becomes contaminated with blood and dung over time and does more harm than good.
Knife
  • This was the old method but has been shown to be much more painful than rubber rings and it should not be used.
  • The blood from newly-cut tail docks only attracts blowflies.
General comments on docking


  • Only dock lambs on dry days and try to keep the docking area clean. This is easy when lambs are docked in the paddocks they were born in, but if done in the regular sheep yards is often more difficult.
  • Keep the equipment clean by occasionally washing with disinfectant.
  • Operators should also try to keep their hands and overalls clean
Disclaimer
This material is provided in good faith for information purposes only, and the author does not accept any liability to any person for actions taken as a result of the information or advice (or the use of such information or advice) provided in these pages.

September 4, 2008

Lamb’s tail docks are too short


This ram's tail is too short. It should be about 80mm longer

Docking is in full swing and too many farmers are not heeding the MAF Sheep Welfare Code and are docking their lambs’ tails too short. The rule is simple to remember – “the dock should be able to wag”!

Docking is done under considerable time pressure on farms, and when using rubber rings, the fastest method is to push the ring along the tail until the pliers hit the lamb’s body before release. This is too short, as the ring needs to be released to leave a dock that will cover the vulva on a female lamb and the equivalent length on a male. This needs a bit more care and time to get into the routine. The same happens with the hot iron guillotine – the dock can be removed too short.

There are very good animal welfare reasons for these recommendations on length of dock. If the lamb can wag its dock, then the muscles and surrounding tissue that control the anus are not damaged, and the lamb will then be able to project any faeces, especially from spring pasture away from the body and remain much cleaner. Otherwise dung runs down the lamb’s back end, causing dags that attract blowflies and this means more work and expense in prevention and treatment.

This advice is based on research reviews from New Zealand and Australian studies which also showed that using rubber rings caused less total stress than the old method of surgical docking with a knife.

The tail dock should certainly not be any longer than this recommended length as it causes extra work and cost in dagging, crutching and shearing. Studies have shown that correctly-docked lambs are generally less daggy than those docked too short.

A tail should drop off in about 10 days after docking and it’s important to check that all the wounds are clean and dry so not to attract blowflies. Tails should be allowed to drop off on their own accord and not be cut off below the ring as this again may attract blowflies that can start to be active very early in the year.

The Code of Recommendations for the Welfare of Sheep is available from the Ministry of Agriculture and Forestry, PO Box 2526, Wellington.