EDINBURGH, Scotland, Aug. 9 (UPI) -- Drug-resistant parasites wreaking havoc on Scotland's sheep and cattle industry were targeted this week under a new government veterinary testing program.
Responding to calls for help from farmers who say their herds are experiencing an alarming increase in sometimes-fatal "liver fluke," Scottish Chief Veterinary Officer Sheila Voas Wednesday announced a new effort to stop the spread of the parasitic flatworms.
"Liver fluke is a serious condition which appears to be on the increase, spreading across Scotland into previously fluke-free areas," she said. "There is also evidence that it is becoming resistant to drugs commonly used to treat the disease, which is why it is so important we establish the best ways of preventing and controlling its spread."
As part of the new effort, sheep will be tested on Kinaldy Farm in Fife by experts from Scotland's Rural College and the Moredun Research Institute, with the results to be passed along to farmers.
The Scottish National Farmers Union urged action in April after first-quarter results from abattoirs showed 36.5 percent of sheep livers tested positive for fluke, up from last year's record total of 29.1 percent.
Positive tests in cattle livers, meanwhile, increased from 11 percent in last year's first quarter to 17.2 percent this year, causing what NFU President Nigel Miller called "a huge degree of loss to Scotland's livestock sector" and "a massive welfare and production challenge for our farmers."
"Veterinary reports indicate that liver fluke has devastated ewe health in some flocks over the past few months while in cattle, even low levels of infection can pull down performance, slow growth rates and increase days to slaughter."
Liver fluke is a large internal parasitic flatworm, picked up by livestock via a mud snail while eating infected plants. It is especially prevalent around muddy ponds and lower pastures.
Incidences took a jump to record levels in 2012, ascribed to an extremely wet spring and summer. But despite much drier and hotter weather this year, the disease is continuing to spread.
It is sometimes fatal to young sheep and its presence can reduce the market value of the infected livestock by as much as 15 percent. There are no vaccines to protect against it, and only one drug -- Triclabendazole or TCBZ -- has ever proven effective against it.
However, reports of resistance against the drug have been noted worldwide, including in Britain, creating a need for early detection.
"This summer season has seen a high prevalence of liver fluke in all ages of sheep submitted for post-mortem examination," Jill Thomson, veterinary manager at Scotland's Rural College, said in announcing the new program.
"A worrying trend has been the appearance of clinical fluke problems as early as June whereas historically, it has been a problem for farms from late-summer onwards. Information on these changing trends is vital for effective health planning purposes."
Swiss veterinary drug manufacturer Novartis has also urged sheep and cattle farmers to step up their fluke prevention efforts.
Fiona Anderson of Novartis Animal Health told The Scottish Farmer in June previous fluke prevention systems were unlikely to control the problem this year.
"There has been a massive increase in the level of fluke on all farms," she said. "Twenty years ago, we never saw liver fluke on the East Coast, but it's there now and ever more present on the West Coast, therefore the treatment of liver fluke is no longer straightforward."