The Veterinary Laboratory Agency has been using a Metrohm 757 analyser to detect selenium - an important trace element - in the blood of horses from the royal stables
The Clinical Chemistry Unit of the Veterinary Laboratory Agency (until recently part of MAFF but now Defra) in Shrewsbury has recently invested in a Metrohm 757 Computrace analyser in order to analyse selenium in the blood of some very special horses from royal stables.
Selenium as a trace element is vital to the well being of horses.
Elevated levels of selenium can lead to hoof damage and then lameness.
Previously the fluorimetric selenium method involved the use of a potent carcinogenic compound, and Alan Hunt was keen to update this method with a more sensitive and safer technique.
Alan is delighted with his Computrace analyser and now uses it for all the routine selenium analysis. Selenium levels are important not just to horses but to all farm animals such as cattle, sheep and pigs.
A deficiency can cause a condition known as White Muscle Disease, which causes a massive necrosis of striated muscle.
The muscle enzyme CPK has reference values in farm species between 20-200 but during white muscle disease values can go up to 60,000 and higher.
Selenium is analysed by the Computrace analyser not only in body tissue such as liver, kidney, heart, serum and blood but also in hay, straw, silage and feed such as pellets.
The next project for the Computrace Analyser is the analysis of cobalt in sheep and cows. The levels of cobalt in an animal are linked to the levels of Vitamin B12.
Sheep have very high Vitamin B12 requirements.
If they are put to pasture on land with low levels of elemental cobalt the rumen organisms cannot manufacture sufficient Vitamin B12 and they then develop a condition known as 'Pine' in which they rapidly loose weight and fade away.
When given cobalt as a treatment however they quickly recover.
What remains a puzzle is that the same phenomenon does not occur in cows.
When the cows are on the same pasture they do not show any signs of Pine, yet their Vitamin B12 levels are very low.
So low in fact that they are sometimes below the limits of detection of the method used.
So it has been decided that the levels of cobalt will be used as one of the ways of investigating the balance between cobalt and vitamin B12 in sheep and cows.
The Veterinary Laboratories Agency of Defra has established The Clinical Chemistry Unit at Shrewsbury as a Centre of Excellence for the biochemical and toxicological testing of blood and tissue samples collected from farm animals.
The lab is involved in the diagnosis of routine metabolic problems, nutritional infertility investigations, trace element and vitamin deficiencies and problems due to a range of toxic heavy metals."
