Rickets In Hoggs In South West Scotland

SRUC Veterinary Services diagnosed rickets in hoggs on several farms during late winter/early spring 2019 so it is worth keeping an eye out for this condition over the next few months, particularly as sheep return from their winter grazings. 

The problem is most common in hill lambs wintered away on good dairy grazing.  However we have also seen it in hoggs on their holding of birth, and in pregnant hoggs. 

Improved nutrition triggers fast growth at a time when cutaneous production of Vitamin D from sunlight is lacking, and animals are reliant solely on dietary Vitamin D.  Vitamin D deficiency results in impaired calcification of new bone and widening of growth plates as shown below.  Affected hoggs may appear stiff or reluctant to move, with recumbency in some cases.  Carpal valgus may be seen.  Both black and white faced hoggs can be affected and the problem may not be noticed until they return home.  Treatment is by supplementation of Vitamin D via concentrates or drench. 

Edinburgh Vet School have developed a test for serum Vitamin D and we are working with them to try and learn more about this condition and how best to treat it.  It is of note that some samples taken and tested in January had undetectable 25(OH) vitamin D3 concentrations, probably not surprising given the weather!

We would be interested to hear about any suspect cases, please contact your nearest disease surveillance centre with any information.

Posted by Veterinary Services on 04/02/2020