Difficult conditions this spring have put sheep farmers under pressure with many reporting an upsurge in cases of coccidiosis – detected by an oocyst count from faecal samples taken from scouring lambs.

Vet, Jenny Hull, a partner with Black Sheep Farm Health in north east England, says this should be done at the earliest opportunity to allow for early diagnosis and treatment.

“A cold, wet and late spring including some snow has put this season’s lambs under particular pressure,” explains Dr Hull.

“Slow grass growth may have also compromised the ewes’ milk production, adding nutritional stress and further increasing the lambs’ susceptibility to disease.”

The situation has also been compounded this year by a build-up of the pathogen in muddy conditions and often seen around troughs inside and out, when lambs have had to be housed for longer, and worsened by a lack of bedding where straw has been scarce.

Her advice is to keep a particular eye on lambs aged three weeks or more whose maternal passive immunity will have started to decline.

“Lambs are particularly susceptible to coccidiosis from four to six weeks. Those which are scouring or stunted, or groups of lambs whose growth appears uneven, should be sampled, ideally by testing around 10 lambs in each batch."

Once the vet has diagnosed coccidiosis, she advised the use of Baycox® as it contains the ingredient, toltrazuril, which treats all stages of the pathogen and is therefore effective for longer than other products

She also recommends specification testing which is offered through vets, free of charge by Bayer to supporting practices, which identifies which strain of coccidiosis is on the farm.

“There are 11 species of coccidiosis which infect sheep, but only two are pathogenic. It’s the pathogenic species which cause disease and significant clinical problems if the lambs are not treated.

“Speciation testing identifies if the cocci present is pathogenic, and so will help with developing a treatment plan for the following year, when it will also be important to practise good husbandry aimed at coccidiosis prevention,” she said.

This includes avoiding faecal contamination, providing clean bedding and regularly moving feed hoppers.

“There is also no reason why Baycox® should not be used for prevention, on farms with a confirmed history of coccidiosis. This will prevent clinical signs and reduce the shedding of oocysts, which are an important element of the disease’s spread.

“Clinical coccidiosis causes severe damage to the intestine and is one of the most economically significant diseases in sheep due to its impact on growth rates. However, early treatment is effective and will bring a performance payback,” concluded Dr Hull.