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A TEXTBOOK OF PHYSIOLOGY 



Weaning. The milk of a mother begins to decrease in quantity 

 at the end of the sixth or seventh month. It is therefore desirable that 

 the child should be partially weaned at this time. A further reason 

 is that the mother's milk is deficient in iron, and this deficiency begins 

 to be felt about this time. It has been shown that the young embryo 

 has stored within it sufficient iron to last it until it can begin to take 

 other food. Thus, in the case of the rabbit, the embryo has enough 

 iron stored until the young animal begins to run about and take green 

 food. 



FIG. 191. PROTEIN REQUIRED FOR WEIGHT AND SURFACE AT DIFFERENT AGES. 



(Waller.) 



IF, W Body weight in kilos (1 mm.= l kilo); S, $=body surface in square metres 

 (1 cm. = l square metre); s, a body surface per 1 kilo body weight in square 

 cms. (1 cm. = l gramme); N, N= protein per kilo body weight in grammes 

 (1 cm. = l gramme). 



During the period of lactation, the mother's dietary must be 

 liberal in the more nutritious foodstuffs. It must be remembered 

 that she is called upon to supply amounts varying from 20 grammes 

 on the first day up to about 1,000 grammes at the end of the sixth 

 or seventh month. As far as possible, also, she must be spared from 

 grief or anxiety, which seriously affect the m ; lk, causing digestive 



