TRACE ELEMENTS IN ANIMALS 137 



loss of appetite with a general degeneration in the condition of 

 the animal. Internally, the proportion of dry matter in the 

 blood is low, being only 13-14 per cent instead of the normal 

 18-20 per cent, while both the iron content and haemoglobin 

 content are generally very low. From what is now known of the 

 part played by copper in haemoglobin formation these are the 

 symptoms which might be expected to result from a shortage 

 of copper. 



That a particular substance is concerned in the disease is 

 indicated by the fact that moving affected animals to land on 

 which reclamation disease does not occur brings about rapid 

 improvement in the animals. That the shortage is not due to 

 iron or manganese, but probably to copper, is indicated by 

 analyses of the hay from farms in which the disease occurs. 

 Such analyses show that there is no constant shortage of either 

 iron or manganese, but that there is consistently an abnormally 

 low content of copper, namely 2-3 p.p.m. and sometimes even 

 less than 1 p.p.m., whereas hay from normal farms contains 

 from 6 to 12 p.p.m. 



Support for the attribution of licking sickness to copper 

 deficiency was obtained by Sjollema by dosing affected animals 

 with copper sulphate. 



Later Sjollema (1938) described another disease of animals 

 which he also attributed to copper deficiency, both cattle and 

 goats being affected. The chief symptoms of this disease, which 

 occurs only on fine dry sandy soils, are diarrhoea, wasting, and in 

 black cattle, loss of colour in the coat which becomes brown-grey. 

 The disease is apparently not the same as licking sickness. 



The evidence adduced by Sjollema in support of copper 

 deficiency as the cause of this second disease is similar to that 

 respecting licking sickness. Thus the copper content of the 

 blood, fiver and milk of affected cows and goats was abnormally 

 low, ana so was the hair of affected cows. The grass and hay 

 from farms on which the disease occurred were low in their 

 content of both copper and manganese, but the quantity of the 

 latter appeared more than adequate for the needs of the animals. 

 The hay was also poor in zinc, but the blood of affected animals 

 contained a normal amount of this element and the liver a 

 higher content than the normal. As regards iron the content of 



