Cattle farmers get one-shot help to tackle costly ‘invisible’ disease

UK cattle farmers have a new solution available to help prevent an 'invisible' disease that has an all-too visible financial effect on calf production. Depressed growth is one of the major effects, and higher mortality rates can be another in extreme cases.

The disease is coccidiosis – one of the common causes of diarrhoea in calves, but the difficulties of diagnosis combined with a lack of awareness mean it is frequently overlooked.

The new solution for farmers is the oral anticoccidial drench Vecoxan™ from Janssen Animal Health, now licensed for use in cattle. Preventive treatment, when coccidiosis is known to be a problem on a farm, with a single dose of Vecoxan has been shown to provide a lift of 20 per cent-plus in average weight gain, says the company's Nick Burford.

Also, it reduces by 98 per cent the excretion of oocysts (eggs) that cause coccidiosis, dramatically cutting contamination of pasture and bedding where calves are housed. Oocysts can remain infective on pasture for up to two years.

The product, which works by disrupting the parasite's life cycle, has a well-proven pedigree in the UK sheep industry. Millions of doses have been given to lambs over the last eight years, contributing significantly to the industry's financial returns.

Coccidiosis is caused by calves picking up oocysts of a single-cell parasite, Eimeria, shed onto pastures in the faeces of previously infected animals. The disease presents calves with a serious uphill health struggle: one ingested oocyst can multiply to 16 million in the 17-22 days the parasite is in the animal. A calf can pick up from 5,000 to 10,000 oocysts a day from pasture or bedding.

On their way through the calf, oocysts cluster along the intestines. They destroy millions of cells in the gut lining, severely reducing the animal's ability to use feed and its capability to grow to its genetic potential.

The high numbers of oocysts produced are shed onto pasture in the dung, causing greater contamination for the present and following groups of calves. The oocysts become infective from two to seven days after being shed.

While animals showing clinical signs of coccidiosis are more badly damaged by the disease, sub-clinical coccidiosis has a greater financial impact on a herd, says Nick Burford. "A six-site trial involving 116 treated calves and a control group of 115 underlines the point."

Treated animals gained an average 16.4 kg, those with sub-clinical disease 14.4 kg (2 kg less) while clinically diseased animals gained just 9.6 kg (6.8 kg less).

Eighteen calves were clinically diseased, with lost potential growth of 122 kg. The remaining 97 calves had sub-clinical disease, and with average losses of 2kg each, it led to losses of 194 kg – a massive 61 per cent of the total.

The signs that calves are clinically diseased include anorexia, weakness, fever, diarrhoea, dehydration, anaemia and signs of abdominal pain. In severe clinical cases blood and intestinal tissue may be found in the dung.

Signs of the disease do not appear until the parasite's life cycle is almost complete. By then, most of the damage has been done. Treatment with Vecoxan will kill all organisms associated with coccidiosis within 12 hours, but clinically diseased animals may continue to scour for a few days and still lose intestinal tissue. They are likely to need further supportive treatment to overcome the effects of dehydration and secondary infection.

Says Nick Burford: "Prevention is better than cure. This metaphylactic treatment, as it is called, is the most effective way to prevent the disease in calves – treating all groups of animals with a single dose of Vecoxan simultaneously soon after they come into contact with the infection (within two weeks) and before the onset of clinical coccidiosis.

"This means treating calves about two weeks after they have been exposed to pasture or bedding likely to be contaminated with oocysts." Calves should receive 1ml Vecoxan/2.5 kg bodyweight.

Vecoxan treatment to control coccidiosis provides a number of key advantages:

 Average weight gain improvement of 20 per cent-plus

 Easy, single dose administration with a drenching gun, as part of farm calf healthcare programme

 Reduced pasture contamination – treated calves shed 98 per cent fewer oocysts

 No interference with the development of the calf's natural immunity

 Zero day meat withdrawal period.

"Coccidiosis can have dire animal welfare and financial consequences. This newly-available solution for beef and dairy farmers will take the stress out of the disease for animals and farmers alike," Nick Burford comments.