Do you know which of these sheep has sheep scab?
Not sure? Only guessing?
Of course you are. It is impossible for you to be certain that either sheep has sheep scab without a diagnosis. Yet every year thousands of sheep are treated on the basis that people think they know. Getting it wrong it will waste your time and money, risk the health of the sheep and result in unnecessary use of products, delay the animal recovering resulting in financial losses and increasing the risk of resistance in the future.
What is sheep scab?
Sheep scab is a major source of economic loss in affected flocks and is a serious threat to sheep welfare. Infestations can be very debilitating with significant loss of condition, secondary infections, hypothermia and eventually deaths. Sheep scab is notifiable in Scotland.
Sheep scab is actually an acute or chronic form of allergic dermatitis caused by the faeces of the Sheep scab mite is Psoroptes ovis. The mite is just about visible to the naked eye and can only remain viable off the host (sheep) for 15-17 days. There are no other hosts for these mites, although they can remain viable on cats. The life-cycle takes 14 days.
Sheep scab can be contracted via any contact with live mites. This is usually through sheep-to-sheep contact at market, in livestock lorries, shared rubbing posts etc. However, shearing combs and cutters, contaminated clothing, tags of wool or scab attached to brambles bushes etc. can also spread scab.
Sheep scab is mainly a winter disease, with most cases occurring between September and April, although a significant number of cases do occur in the summer months, particularly on animals still full fleeced (lambs, hoggs etc) and on "ridges" of longer fleece on poorly shorn sheep.
During the early stages of sheep scab, infestations are not obvious and animals often appear clinically normal. Early disease is involves low mite numbers and very small lesions which are virtually undetectable. Sheep with early infestations may show no signs or simply be restless, rubbing against fence posts, have soiled and stained areas of wool toss their heads or have deranged or tags of fleece. At these early stages, sheep can look perfectly normal and can unknowingly be introduced to a flock.
Later stages of infestation see high mite numbers the lesions spread. Scab mites cannot feed on the hardened scab so they are forced to go to the edge of the lesion, making it spread out. Rubbing and head tossing becomes more and more excessive, areas of wool loss may appear often with open, bleeding wounds. Sheep rapidly lose condition and serious cases will start fitting.
Get a diagnosis
If you suspect your sheep have sheep scab, don’t guess, contact your Vet and get a diagnosis before deciding what action to take. Test available include examining skin scrapings taken from suspect sheep and a recently blood test recently developed by Moredun. This detects antibodies to a specific protein found only in the sheep scab mite, which means that the test can accurately determine there or have been are scab mites present. The test can also detect scab mite infestation at an early stage, before the onset of clinical symptoms.
1. Establish where the scab came from
If purchased or incoming sheep review quarantine protocols.
Neighbours (see below)
2. Contact neighbours with sheep in adjacent fields to warm them and/or suggest they treat at the same time as you for maximum effect and protection.
3. Check common fence-lines for gaps/shared rubbing areas. Consider double fencing any in contact with high risk neighbours.
Always read the manufacturer's instructions before use. Withdrawal periods are subject to change and it is the user’s responsibility to ensure withdrawal period is adhered to.
|Injectable Products For Scab||Company||Chemical||Use And Protection Against Infestation||Meat Withdrawl Period|
|Cydectin 1%||Zoetis||Moxidectin||Prevention - one injection protects against infestation for 2 days. Treatment - two injections 10 days apart||70 days|
|Cydectin 20mg/ml LA injection (2%)||Zoetis||Moxidectin||Prevention against infection or reinfection - 60 days after one injection.Treatment - one injection in base of the ear.||104 days|
|Dectomax 10mg/ml Solution for Injection for Cattle and Sheep||Elanco AH||Doramectin||Treatment : one injection. Avoid contact with untreated or infected and treated flocks for 14 days.||70 days|
|Ecomectin 10mg/ml Solution for Injection||Eco Animal Health||Ivermectin||Treatment: Two injections 7 days apart.||42 days|
|Ivomec Classic||Merial AH||Ivermectin||Treatment: two injections 7 days apart.||37 days|
|Noromectin 1% Multi Injection||Norbrook Labs||Ivermectin||Treatment: Two injections 7 days apart||42 days|
|Panomec Injection for Cattle, Sheep and Pigs||Merial AH||Ivermectin||Treatment: Two injections 7 days apart.||37 days|
|Paramectin Multi Injection||Norbrook Labs||Ivermectin||Treatment: Two injections 7 days apart.||42 days|
|Premadex 1% Injection||Downland||Ivermectin||Treatment: Two injections 7 days apart.||43 days|
|Qualimec Injection 10mg/ml Solution for Injection||Elanco AH||Ivermectin||Treatment: Two injections 7 days apart.||42 days|
|Zermex 1% Injection||Downland||Moxidectin||Prevention - one injection protects against infestation for 28 days. Treatment - two injections 10 days apart.||70 days|
|Zermex 20mg/ml LA for injection (2%)||Downland||Moxidectin||One injection for treatment and prevention. Persistency of reinfection - 60 days.||104 days|
|Plunge Dips For Scab Control||Company||Chemical||Treatment And Protection||Meat Withdrawl Period|
|Osmonds Gold Fleece Dip||Bimeda||Diazinon||Treatment and up to 4 weeks protection.||49 days|
|Paracide 62||Animax Ltd||Diazinon||Treatment and up to 4 weeks protection.||70 days|