21 October 2010

3 minute read

Europe

Luke O'Grady, a speaker at the Cattle Association of Veterinary Ireland's autumn conference, says cow nutrition has an influence on many production diseases and issues associated with these, such as retained afterbirths.

A bolus is a guaranteed means of ensuring cows are not affected by low intakes of selenium, a trace element that is key to preventing retained afterbirths.

"Nutrition is a very important component in preventing retained placentas," Mr O'Grady told the conference at Enfield, County Meath.

The incidence of retained placentas is highly variable between farms and also varies from year to year but Mr O'Grady said the target should be less than 10 per cent of the herd.

The repercussions of this condition are severe metritis, poor fertility, lost milk production and, as a consequence, an increased cull rate. Mr O'Grady said many cases of retained placentas are linked to poor nutrition.

"When you go to investigate the problem on farm, in around half of the cases the blame lies with the nutrition being fed," Mr O'Grady told the gathering of vets.

He described selenium as a very important trace element in the expulsion of foetal membranes.

"When there is low selenium in a herd, cases of retained foetal membranes will be worse," he explained.

For this reason it is vital to examine the diet of the dry cow, in particular during the transition period prior to calving.

"You have to look at what's going into the cows, what supplements they are getting," said Mr O'Grady.

"My personal preference is boluses and injections as these guarantee that the animal is getting what she needs."

Veterinarian Les Porter, of Animax Ltd, which produces trace element boluses, is delighted that Mr O'Grady endorses boluses as a preventative against retained placentas.

"The benefit of boluses is that a cow gets all four key trace elements - selenium, cobalt, copper and iodine - to protect her health at calving while an injection only delivers a single trace element. There is also the associated risk of an abscess developing at the injection site," said Mr Porter.

Phil Rogers was involved in research at Teagasc that led to the development of Animax trace element boluses. He agreed that in Ireland very few farms have a single deficiency.

It is very common to have all four minerals deficient on the same farm, he said.

Reflecting on the development of the boluses, he said: "We didn't want a piecemeal system where some farmers were giving cobalt, some copper and so on.

"One of the systems we developed then in relation to multiple trace elements was Ionox which included cobalt, selenium and iodine and that was further developed by the company to include copper which is the main problem so all four elements are present today."

This bolus is known as Tracesure Cu/I.

Mr Rogers said giving boluses to cows in the run up to calving can go a long way to cutting down the number of retained placentas.

"With self feed silage it's very difficult to dose properly with a mineral and in that situation there is a lot to be said for boluses," said Mr Rogers.

A delegate at the CAVI conference, veterinary surgeon Joe O'Keeffe, of Kinnegad, County Westmeath, has been using boluses in his suckler herd for years as a means of safeguarding against retained placentas and to improve fertility.

Mr O'Keeffe says use of the bolus method of trace element supplementation has rocketed in recent years. "Everyone is using them now and they are finding they can't work without them," he said.