A pilot study that involved surveying sheep disease on four farms in the eastern wheatbelt of Western Australia has shown how regularly WA farmers routinely check the health of their sheep.
Department of Agriculture and Food, Western Australia veterinarian Dr Roy Butler, who spoke about the study at the Australian Sheep Veterinarians conference, said that some of the most frequent observations made were death, skin lesions and lameness.
“The key purpose of the study was to find out how often farmers were inspecting their sheep and whether it was often enough to detect disease before it had spread to multiple animals or multiple animals had died. We also wanted to get an idea of the number and type of diseases occurring on sheep farms.
The four participating farms were fairly large, from 2,800 to 4,400 hectares and had between 500 to 1,700 merino sheep.
“Given the size of the farms and number of sheep involved, farmers tended to observe one to two groups of sheep at least every two days during routine husbandry activities such as feeding, watering or moving between paddocks, as well as shearing and drenching.
“Inspections for the primary purpose of checking the health of sheep were less frequent and mainly occurred during lambing,” he said.
Each farmer’s recorded observations of disease were collected during monthly visits to the farms.
“In most cases deaths related to either infant lambs or from complications to female sheep while giving birth and dog attacks. Most causes of lameness were a result of injury or bacterial arthritis and lice and flystrike were the usual culprits behind skin lesions.”
According to Dr Butler there was only one disease outbreak that prompted a farmer to report outside Dr Butler’s scheduled monthly visit during the survey period.
“One farmer noticed two dead sheep and by the end of the outbreak around 40 sheep had died as a result of lactic acidosis – grain overload or poisoning.
“This type of passive surveillance provides valuable information on disease occurrence in livestock in Australia. In this particular study, only small numbers of sheep became ill or died. But many of the syndromes that were observed were consistent with some clinical signs of various emergency animal diseases not present in Australia.
“It’s vital that farmers call a vet to investigate whenever livestock die unexpectedly so that we can rule out any diseases that could affect public health or trade. Laboratory data from these investigations is also used to support Australia’s excellent animal health status,” he said.