174 MILK AND ITS HYGIENIC RELATIONS 



Experiments on Rabbits. These have been carried out by 

 several observers, but young rabbits appear to thrive no better 

 upon cows' milk than do young guinea-pigs. This is probably 

 owing to the great difference in composition between rabbits' milk 

 and cows' milk, as some reduction in the mortality was obtained 

 when cream and sugar were added to the milk. 



Experiments on Dogs. A considerable amount of work has 

 been carried out on puppies in order to ascertain any differences 

 which may exist between the nutritive value of raw and boiled 

 cows' milk. It appeared that in every instance the breast-fed 

 puppies were very greatly superior to' any of the artificially-fed 

 ones at the end of the experiments, which lasted a considerable 

 time in each case. As regards the series of artificially-fed animals, 

 the gain in weight in relation to the food was either almost identical 

 or showed a slightly higher figure for the dogs fed on boiled cows' 

 milk. 



Experiments on Kittens. Comparatively little work has been 

 carried out upon kittens. Although the kitten, when it reaches the 

 age when it can leave its mother, appears to be able to utilise cows' 

 milk very readily, it would seem that until this period has been 

 reached cows' milk, whether raw or boiled, is not a suitable food 

 for kittens. Most of the animals upon which these experiments 

 were carried out either died or apparently would have died, had 

 the experiments been continued. 



Experiments on Pigs. Here also a good deal of work has been 

 carried out. Speaking generally, the results are very similar to 

 those obtained by experimentation on puppies. In every case 

 the breast-fed pigs were superior to the artificially-fed ones, not 

 only during the experiment, but also later, when the experiment 

 had ceased for some considerable time. The milk used for the 

 artificially-fed pigs was of the highest quality, but two pigs were 

 fed on market milk, in one case raw and in the other boiled. It 

 appeared that in the pigs fed on the best milk, a slight superiority 

 was noticed in the raw milk as against the boiled milk. In the 

 pigs fed on market milk, however, the reverse was the case. 



Experiments on Goats. Briining and Briickler both fed kids 

 upon raw and boiled cows' milk. The small number of animals 

 available reduces somewhat the value of the experiment ; as, how- 

 ever, they show the same general features as those just considered, 

 they afford useful corroborative evidence. 



General Summary. Summarising the results of work upon 

 animals, the superiority of breast-feeding may be regarded as the , 

 most striking feature. In regard to artificial feeding, very little 

 difference, if any, appears to be detected between the different 

 forms of milk that is, raw or boiled. In some instances the boilecl 

 milk appears t6 be better utilised than the raw, while in one or two 

 cases the reverse is found to be the case. Generally, however, no 

 marked difference was shown. 



