Australia-New cattle disease are we becoming to health concious.

Pestivirus is the latest buzz word in the beef industry.

In fact it’s been an underlying problem for 80pc of breeding herds across all breeds in Australia for many years.

Due to the complexity of this viral infection, Pestivirus is largely ignored while the symptoms and financial losses have been dismissed or attributed to other reproductive and production problems.

Pestivirus is widespread in Australia, mainly in cattle.

Some adult cattle are immune to the disease, while others are life-long carriers.

If a foetus becomes infected within the first three to four months of gestation then it will fail to develop antibodies towards the virus.

In these cases the animals often die before birth or shortly after.

Symptoms of Pestivirus infection include diarrhoea, respiratory problems and bleeding disorders.

Marc Greening, Injemira Poll Hereford and Hereford Stud, Book Book, NSW says there are numerous, simple questions to firmly ascertain whether your herd has a potential problem.

"Fertility is the first; does your breeding herd meet expectations regarding conception rates?" Mr Greening said.

"Next is deaths, is there evidence of still born calves or calves that perish within days of birth that in the past have been put down to scours or other problems?

"Consistency; do you have an uneven drop of calves with large weight variance at weaning?

"Finally appearance; is there general poor health in some calves up to two years of age with excess mucosal discharge and a ’woody’ appearance?

"If the answer to any of these questions is yes, due to a greater understanding of the problem there is a simple strategy to test and subsequently move your herd to a Pestivirus free status."

He points out from a commercial breeder’s perspective, the largest economic loss is the reduction of fertility in their herd.

The exposure through nose to nose contact of previously unexposed females at the time of joining or within the first 100 days of pregnancy is when the herd will suffer the most.

Leading cattle veterinarian, Andrew Todd, Holbrook Veterinary Centre, NSW, recommends conducting serology tests on a random sample of heifers at the pre-joining stage to assess the level of natural immunity within that breeding group.

Then a vaccination strategy can be undertaken if required.

Mr Greening added the most cost effective way to gradually move your herd to a free status is via a ’two-shot’ vaccination program to maiden heifers six to eight weeks prior to joining, followed by another vaccination two to four weeks prior to putting the bulls out.

In subsequent breeding years a single booster vaccination prior to joining for the remainder of the females breeding life will ensure a productive Pestivirus free status.

The introduction of sires into breeding programs has to be also monitored to ensure no persistently infected (PI) sires are introduced.

All sires used in the program should receive vaccination prior to joining.

"Breeders should discuss and encourage their bull suppliers to implement a Pestivirus strategy within their respective stud herd," Mr Greening said.

"It’s too great a risk purchasing untested and non-vaccinated bulls."

Mr Greening said from a seedstock perspective, further steps can be implemented to ensure that the seedstock supplier is providing bulls that aren’t persistently infected and have immunity to Pestivirus.

"At Injemira and some other leading stud herds we’ve introduced the ’ear notch’ test along with vaccination of heifers and natural exposure strategies," he said.

"The end result being, that all future sires sold at our sales are free of Pestivirus and only require booster shots for the duration of their breeding life.

"It’s a relatively small expense, incorporated in full bull health treatments enabling us (Injemira) to offer a complete package."

Injemira will be conducting its 38th annual Bull Sale on 26th February, 2009, at Kiloran, Book Book outside Wagga Wagga, NSW, with this year’s offering including 52 fully tested and vaccinated breed leading Poll and dehorned Hereford bulls.

Experts on the disease will be in attendance at the sale to answer all questions regarding Pestivirus.