Hyperlipemia highly prevalent in aged and ill donkeys
MedWire News: Hyperlipemia is a common disorder affecting donkeys and is associated with mortality rates of around 50%, UK researchers have found.
They say that donkeys typically develop hyperlipemia in response to stress or primary illness and urge veterinarians to intervene to manage the condition and its risk factors.
The study was undertaken by Faith Burden and colleagues from The Donkey Sanctuary in Devon, UK, and aimed to identify potential risk factors for hyperlipemia in a population of aged donkeys.
The team retrospectively identified 449 donkeys diagnosed with clinical hyperlipemia between January 2005 and December 2008 and matched each animal with two healthy control donkeys.
Among the animals with hyperlipemia, the mean age was 28.6 years and the median body condition score was 3 out of 5. There were 226 females, 220 geldings, and three stallions; animals tended to be normal weight or overweight rather than underweight.
Interestingly, nearly three-quarters of hyperlipemic animals had concurrent disease compared with just 6% of healthy animals. The most common concurrent illnesses were liver disease, colic, kidney disease, respiratory disease, and laminitis.
In multivariate analysis, several factors emerged as independent predictors for hyperlipemia. These were older age (odds ratio [OR]=1.26); concentrate feed (OR=1.87); cardboard bedding (OR=3.86); weight loss of more than 10 kg in the previous month (OR=6.40); recent transfer to a new site (OR=3.94); concurrent disease (OR=76.98); recent history of poor appetite (OR=3.23); recent weight loss (OR=2.03); dental disease (OR=1. 73); and antibiotic therapy (OR=0.30).
Hyperlipemic donkeys were nearly twice as likely to die as healthy donkeys, with crude mortality rates of 48.5% versus 28.9%.
Interestingly, mortality rates were significantly associated with peak serum triglyceride concentrations, rising from 41% at levels of 4.4-8.0 mmol/L through to 76% at levels greater than 20.0 mmol/L.
Commenting on their study, Burden et al say that donkeys seem frequently to develop hyperlipemia in response to stress or other illness, and that this reaction is most pronounced in older animals.
"The mere fact of the donkey being ill is more important than the specific disease process that put the donkey at risk," they remark, adding that their results "confirm the long-held belief that every sick donkey must be considered either to have hyperlipemia or to be at great risk of developing hyperlipemia."
The team concludes: "The study provides useful insights into health and management risk factors that may be focused on to further decrease the risk of hyperlipemia both in the population of donkeys studied and in the donkey population as a whole."
By Joanna Lyford