View Full Version : The Viral Menace

16-03-04, 04:33 PM
I was reading an article recently written by Steven Tanner BVSc and thought I would post this for some breeders out there.

Many mares are now at or approaching the halfway stage of their pregnancy. Viral abortion can be heartbreaking - a healthy mare one day, aborting mare the next, and all due to a silent infection contracted days, weeks or months earlier. Also frustrating and often costly is the situation where your horse, in work for months gets the 'flu just before the big day and cannot be ridden or performs poorly.

Equine Herpesvirus may be the culprit in both situations. Equine Herpesvirus principally effects the reproductive and respiratory systems causing abortions and respiratory infections, and in rare cases the central nervous system is affected.

There are 2 types of Herpesvirus in Australia, EHV1 and EHV4. EHV4 causes common respiratory infection and infrequently causes abortion. Often referred to as a 'cold' or the 'virus' in some animals, it may lead to bronchopneumonia. EHV1 commonly causes abortion and low percentage of respiratory infections. The neurological form, which can be seen as wobbling, paralysis and death, is an allergic reaction to EHV1

Respiratory infection presents as depression, fever, nasal discharge, congestion and a cough. Jaw lymph nodes swell and can become painful for extended periods. Training and competition with the sick horse must be stopped until infection resolves. Performance will be poor and serious complications can follow if adequate rest is not undertaken.

EHV1 abortions occur without warning, usually in the last 3 months of pregnancy. Exposure of pregnant mares to the virus may result in the fetus dying. This may occur witin days of infection or months later. The pregnanct mare is outwardly normal one moment and expels a dead fetus or a live but weak foal with dies soon after. Because the mare is outwardly normal she may infect other mares at the same time. Some infected animals become persistent silent shedders of the virus for their life, infecting other horses but not showing any signs of infection themselves.

Vaccination with Duvaxyn EHV1.4 is your mare's only protection against viral abortion and your performance/show horse's protection against viral respiratory infection. Mares require multiple vaccinations during pregnancy. Performance horses require regular vaccinations to protect them against respiratory infections with initial vaccinations 4 weeks apart then 6 monthly boosters.

*** This all pretty scary stuff really. Hope it helps you out there with your mares, I know mine are all lining up for their needles this week***

Lisa Wright
10-04-04, 02:15 PM
I hope all goes well
I will send you a vaccination program for your horse if you like it it can be filled in for each of your horses with the the card staying with the horse so its history is there for other owners vacc every 6 mth first at 6 mth of age
double thumbs up
jd wright vet con
dick wright Equine Specialist

16-04-04, 10:37 AM
Hi Lisa
I have sent you an email regarding your kind offer of a vaccination card. Many thanks for this - it would be most appreciated.

I am glad that someone actually read the post, as I was trying to alert breeders on this subject. Many breeders were affected by this viral menace last year, and we had one mare sucumb to the infection.

Fortunately we pounced on the problem and isolated her, vaccinating the others and didnt loose any more foals.

After talking to vets in our area, it was definately something that was affecting many mares in our district. We have put into place strict protocols now, where our mares are kept separate from outside mares and even our horses that are out competing do not come into contact with the breeding mares at all. We certainly dont take on the 'she'll be right mate' attitude anymore. Our babies are far to precious to mess about with - hence happy healthy mums and bubs in the paddocks!