Bundaberg Hospital   07 4151 5044
Gin Gin Clinic   07 4157 3991
Bargara Clinic   07 4130 5003
Pet Superstore   07 4152 5939
24 Hour Emergencies:

Animal Care Library

Use our Animal Care Library for quick, easy access to our most common animal care problems. Use our Animal Care Library for quick, easy access to our most common animal care problems. Use our Animal Care Library for quick, easy access to our most common animal care problems.

Search Library

Hairy Caterpillars and Abortions Species: Horses

Hairy caterpillars are now proven causes of horse abortions and the birth of sick foals. Breeding horses is a roller coaster ride and over the years the improvements in management by owners, information and research available to veterinarians, vaccinations and the availability of advanced equiptment, has lead to improvements in breeding success and efficiency.

One thing that has recently got a lot of interest is abortions related to the hairy caterpillars. The link between these caterpillars and horse abortions was first suspected in 2001. Now it is recognised in many areas with several different breeds of these caterpillars.

The current research suggests that mares can abort from eating whole caterpillars and also from eating parts of the carterpillars. The important parts of the caterpillar are the skins that they shed when they are growing. These skins are left behind in the 'bags' when the caterpillars move out of the trees and can blow about in the breeze for large distances as each skin can weigh as little as 0.01 of a gram. The abortions in mares can be early term or late term abortions.

The early term abortions often have no signs that the mare has lost her foal and have been reported between 32-140 days of pregnancy. Some mares loosing their foals at this stage will show a vaginal discharge as the only external sign.

The late abortions have been found from mid-term pregnancy through to full term pregnancy and most mares do not show any signs prior to aborting. Some foals go through the full pregnancy and then are delivered with intact membranes ('red bag' deliveries) and the foal may not survive even with intensive care.

Prevention of these losses:

Browse the Library

Browse by Species


Bladder stones, parvovirus, chocolate poisoning, anal gland disease and more... Learn more...


Multi cat households, feline aids, feline lower urinary tract disease (flutd), feeding cats and more... Learn more...


Worming, hoof abcesses, winter check list for old horses, colic and more... Learn more...


Parrot fever, stress in birds and more... Learn more...


Three day sickness, pregnancy testing, tick fever, bull testing and more... Learn more...

Small Ruminants

Pulpy kidney disease, worms, alpaca answers and more... Learn more...