EXPERIMENTAL DATA OF RAW AND BOILED MILK 179 



difference between the mice of the different batches. Some digestive 

 disturbances were present, but these were obviated by preventing 

 the contamination of the food by faeces. 



Experiments on Rats. Some experiments were carried out by 

 myself on rats, but the animals, though young, were no longer of 

 an age when suckling is necessary. The rats were fed in batches 

 of one dozen upon raw, boiled, and dried milk, and a little bread. 

 In one series those fed upon dried milk showed a slightly more 

 rapid gain in weight than those fed upon boiled milk, and these 

 again a rather more rapid gain than those fed upon raw milk. In 

 two other series fed upon raw and boiled milk respectively, no 

 difference could be detected between the rats of either series. 



In making any deductions from these experiments bearing on 

 the feeding of infants the sources of fallacy are, that the rats were 

 no longer of suckling age, and that they received bread as well as 

 milk. As, however, all the batches received the same percentage 

 of milk and bread per kilo, of body- weight, it may reasonably be 

 inferred from these experiments that rats just past the suckling 

 age are able to utilise dried and boiled milk fully as well as raw milk. 



Experiments on Rabbits. It appears that rabbits are scarcely 

 suitable animals for the purposes of such experiments, nor are 

 they at all easy to use. 



It is difficult to get young rabbits to drink out of a bottle ; also 

 rabbits' milk is much richer in fat than cows' milk and thus com- 

 plications are introduced as to the amount of food required to 

 supplement mother's milk. 



Bnining (3) (1906) carried out some experiments on young 

 rabbits five days old. One rabbit of the litter was left with its 

 mother, another was given raw cows' milk with the addition of 

 cream, and the other boiled cows' milk, also with the addition of 

 cream. The rabbit fed upon raw milk died upon the eleventh 

 day of the experiment, and the one fed upon boiled cows' milk 

 was in a greatly inferior condition to the one left with its mother. 

 No comparisons are possible between the effects of the raw and 

 boiled cows' milk since one of the animals died. 



Moro (1907) fed young rabbits upon both human and cows' 

 milk, raw and boiled. Nearly all the animals died, in spite of the 

 fact that they took the food well. If they were allowed mixed 

 feeding of rabbits' milk and cows' milk they rarely showed any 

 untoward symptoms, and if these occurred the attack was warded 

 off by stopping the cows' milk and giving only mother's milk. 

 The addition of cream and sugar to the cows' milk gave better 

 results and the animals lived longer. It seems, therefore, that 

 young rabbits do not thrive either on raw or boiled cows' milk or 

 human milk, and hence are hardly suitable for making deductions as 

 to the relative nutritive value of raw and boiled cows' milk as 

 a food for infants. 



Experiments on Dogs. A considerable number of experiments 



N 2 



