Selenium, vitamin E and polyunsaturated fatty acid concentrations in goat kids with and without nutritional myodegeneration

Abstract

Mean selenium and vitamin E (α-tocopherol) concentrations in the liver, myocardium and skeletal muscle of nine goat kids with nutritional myodegeneration (NMD) were significantly lower than those in a group of nine kids dying from other causes. Each of the 18 kids was from a different property in the southern half of the North Island. The polyunsaturated fatty acid composition of the liver, myocardium and skeletal muscle was not significantly different between the two groups, but the overall level of peroxidisable polyunsaturated fatty acids appeared high in both groups.

A further 21 kids with confirmed NMD and live ‘controls’ submitted as routine cases to Pahnerston North Animal Health Laboratory, were included with the above 18 kids in a comparison of liver selenium and α-tocopherol concentrations. Kids with NMD had liver selenium concentrations ranging from 170– 1100 (mean = 380) nmol/kg and α-tocopherol from 0.7–11.0 (mean =2.2) μmol/kg. In control kids, the liver selenium concentration ranged from 530–4300 (mean = 1220) nmol/kg and α-tocopherol from 1.7– 14.0 (mean = 5.6) μmol/kg. Although these ranges overlapped, the results suggest that liver selenium concentrations <500 nmol/kg and α-tocopherol concentrations <2.5 μmol/kg should be regarded as deficient. Liver selenium concentrations from 500–1100 nmol/kg and α-tocopherol concentrations from 2.5-10 μmol/kg should be considered marginal.

Goat kids appear to require more selenium than lambs or calves which may explain the higher prevalence of NMD in kids. In some cases, however, the disease is associated with low α-tocopherol suggesting that supplementation with selenium alone may not always be sufficient.