When first acquiring sheep or moving to a new area it is a good idea to make contact with your vet. They will be only too pleased to help you put together a flock health plan and will also be aware of any problems specific to your area. Below are a few of the more common tasks and problems.
Worming
How often you worm very much depends on the stocking density on the land, whether the land has had sheep on in the past, where the sheep came from and what other animals have grazed the land. Mixed grazing by cattle/horses and sheep, either simultaneously or in rotation will tend to reduce the parasite challenge for both species since each species eats parasite larvae indiscriminately, but only the larvae specific to the host species can usually survive.
In recent years there has been evidence of increasing worm resistance to anthelmintics and there has been a change in the general advice given. More and more animal keepers are taking faecal egg counts to assess flock burden and the type of worm/worms to be treated. Good up to date information can be obtained from www.scops.org.uk. It is also a good idea to consult with your vet who will help you devise a programme that is suitable for your sheep and the area you live in.
Foot Care
Sheep’s feet need checking regularly and if overgrown given a light trimming taking care to leave sufficient wall to take the weight of the sheep. Most outbreaks of lameness in sheep are caused by either interdigital dermatitis (scald) or footrot.
Individual cases of scald can be treated using oxytetracycline aerosol spray. If many animals are affected a solution of either 10% zinc sulphate or 3% formalin in a footbath provides a good means of control.
Footrot can be treated with an injection of long acting antibiotic together with removal of debris from the foot and an application of anti-bacterial spray. However, the bacteria responsible for footrot can persist in the soil and cause constant re-infection. If this is the case it may be necessary to talk to your vet about vaccinating.
Further information on foot care can be found on www.nadis.org.uk.
Shearing
Shetlands can be sheared or ‘rooed’. The latter is a form of ‘plucking’ when the wool is ‘ready’. During the winter the wool growth in primitive sheep slows down but once the spring conditions arrive, or after lambing, the growth starts again causing a distinct ‘rise’ or line to show in the fleece.
On some Shetlands this 'rise' is so marked that it causes the old fleece to break away and this is when it can be ‘rooed’.
In others the fleece does not come away easily and it is better to shear just on or below the old fleece line and so avoid contaminating your fleece with the new growth. If you hand shear then you have the distinct advantage of being able to select the optimum shearing time for each individual sheep; if you use a contractor then of course you are tied to his timetable.
Flystrike
Flystrike is caused by the sheep blowfly which usually lays its eggs in damp or dirty fleece, however if the atmospheric conditions are favourable even clean sheep are at risk. Vigilance is needed throughout the high risk months. When the maggots hatch they burrow into the flesh injecting a toxin into the wounds which will send the sheep into shock and possibly eventual death if not treated in time.
The blowfly is active in the south from April to December and in the north from June to November.
Affected sheep are often on their own, restless, with head looking back. They may bite, kick or rub at the struck area. On closer examination the wool overlying struck areas may be discoloured, moist and foul smelling, even if this is not the case take the time to part the wool down to the skin. Flystrike is always better caught early and before too much damage has occurred. 80% of flystrikes occur on the breech so crutching is beneficial.
Prior to shearing the sheep are very vulnerable to strike but it should be noted that the application of insecticide formulations can spoil fleeces which are to be processed. After shearing the sheep is safe until the wool has grown a few centimetres, then a preventative spray such as Clik, Vetrazin or Crovect can be applied.
Vaccinations
Some breeders use a programme of vaccination against many of the common diseases including the Clostridials and Pasturella. The most commonly used product is Heptavac P+. After the initial two injections, 4-6 weeks apart, only an annual booster is required which is usually given 4 weeks before a ewe lambs, so that the protection will be passed temporarily on to her offspring.
Blue Tongue
Blue tongue is a disease caused by a virus spread by biting midges which affects ruminants. The current disease situation is that GB was officially declared to be free from blue tongue on 5 July 2011. This means that we will no longer be able to vaccinate against BTV8 or any other serotype under EU law.
Schmallenberg Virus
This virus is a livestock disease that has been detected in Belgium, Germany, I Netherlands and the UK. It is transmitted by biting midges. In sheep the virus causes abnormalities in animals born alive or dead at term or aborted. Malformations include bent limbs, fixed joints, twisted neck or spine and domed appearance to the skull. Some are born with an outwardly normal appearance but may be blind or suffer from fits. The foetal deformities vary depending on when the infection occurred during pregnancy.
Check with your vet for the latest treatment or vaccine for this disease.