Significant sums of money will be invested in flock replacements over the coming months through the purchase of breeding rams or female replacements.

There are very few farms operating a 100% closed breeding policy, with rams purchased periodically.

A robust quarantine protocol is important from two perspectives – to safeguard your investment and reduce the risk of bringing disease on to the farm.

Two components

There are two main components of a good quarantine protocol - administering health treatments to reduce known disease risks and keeping animals quarantined for a sufficient period so that if animals exhibit disease symptoms action can be taken before the risk is spread to the entire flock.

The longer newly purchased animals can be kept away from animals currently on the farm the better.

As a general rule, breeding animals should be quarantined for a minimum of 21 days and preferably 28 days before joining the rest of the flock.

On arrival to a farm, sheep should be housed or held in a yard for a period of 24 to 48 hours until the initial health treatments are administered.

Some people like to join a new ram with some companion animals to help them settle on arrival to the farm. Once this happens, then these animals should also be treated similarly.

Anthelmintic resistance

Despite efforts to increase awareness, the incidence of anthelmintic resistance continues to grow across all livestock enterprises.

It has long been known that there are issues with benzimidazoles or white drenches, but more farmers are now worryingly identifying resistance with avermectin- and levamisole-based products.

Animals should be dosed to reduce the risk of bringing worms or liver fluke parasites on to the farm which have developed resistance against anthelmintics and flukicides.

The latest advice is to treat sheep with a moxidectin-based product and a new-generation wormer on arrival to the farm.

Startect is still not available to farmers in Ireland currently, while reports suggest there has been some recent supply issues with Zolvix, which should hopefully be sorted now.

Zolvix is a prescription-only medicine and as many veterinarians do not stock it as standard, it is important to order it well in advance of when it will be required.

Sheep should be treated on arrival and kept off pasture for 24 to 48 hours

Where there is no chance of implementing this option then the next best option for most farms is treating purchased sheep with a moxidectin-based product and a levamisole-based wormer.

Sheep should be treated on arrival and kept off pasture for 24 to 48 hours, so that worm eggs present in the gut will not pass on to pasture.

Following treatment, sheep should be turned out to pasture that is referred to as dirty - that is ground that has been previously grazed by sheep.

Liver fluke

The risk of liver fluke will be influenced by the ground on which sheep were grazing prior to purchase and the time of year.

Where the health status cannot be identified, then animals should be treated as potentially posing a liver fluke risk.

The current advice is to use a product containing trichlabendazole and another product with an active ingredient, such as closantel, to safeguard against liver fluke resistance to trichlabendazole.

External parasites

When it comes to external parasites, dipping is the optimum method for controlling external parasite risks, such as sheep scab, lice, ticks, etc.

For complete control, sheep should be immersed for 60 seconds, with their head plunged under the solution at least once.

There is no one product outside of dipping that will control all external parasites in one treatment.

There are injectable products that will treat sheep scab, while certain pour-ons will provide cover for lice, ticks, etc.

Given the increase in anthelmintic resistance to avermectin-based products, Teagasc is recommending against the use of avermectins for routine treatment to control sheep scab.

The preference, where at all possible, is to carry out plunge dipping to address external parasites.

Lameness control

In terms of lameness, the most damaging risk is the introduction of contagious ovine digital dermatitis (CODD).

It can be identified by an infection at the coronary band and, in advanced cases, the hoof horn will be lifting away from the band.

It is important to check sheep closely for this ailment, as once it establishes in a flock it is hard to get on top of. Treatment options are limited and require veterinary approval.

Footrot is also a significant risk and, again, sheep should be examined for signs of the disease.

Sheep should be footbathed as a precautionary measure and a treatment plan should be put in place for any lame sheep.

Isolate any sheep from the rest of the flock until you are sure all problems have been addressed.

Footbathing will not cure footrot and antibiotic treatment may also be necessary.

There is one option for vaccination for footrot, with Footvax offering preventative and also treatment properties.

Vaccination considerations

Vaccinations are not cheap to administer, but their cost can be justified given the level of damage that can occur if there is an outbreak of an abortion-causing agent, pneumonia, clostridial diseases or, as mentioned already, diseases causing lameness.

Their use can be reduced in some cases by purchasing from known high-health status flocks.

The three main ones to consider are clostridial disease, enzootic abortion and toxoplasmosis.

Where the status is unknown for clostridial diseases, sheep will need a primary treatment post-arrival followed by a booster vaccine.

Unfortunately, the incidence of enzootic abortion or chylamdia abortus, a highly contagious abortion-causing disease of sheep that hits in late pregnancy, is steadily increasing.

The only vaccine available is Enzovax, which is administered at least four weeks before the start of the breeding season.

It can be administered at the same time as Toxovax, which prevents toxoplasmosis, and must be administered at least three weeks before the start of the breeding season.

Iceberg diseases

Sheep farmers need to be mindful of a range of other diseases, such as ovine pulmonary adenocarcinoma (OPA) or Jaagsiekte, caseous lymphadenitis (CLA), Johnes disease and maedi-visna.

These are hard to distinguish and strengthen the argument for implementing as long a quarantine period as possible and purchasing where possible from known sources.