REPRODUCTIVE SYSTEM GENERALLY. 257 



extreme limits ; but, according to other observations, in 

 582 mares, the shortest being 78 days before the expiration 

 of 12 months, the longest 58 days after the full term had 

 passed, making the extraordinary difference between the 

 two extremes of 13G days, or 4 months and 16 days be- 

 tween the births of two animals of the same species. 



Parturition or foaling. — The premonitory symptoms of 

 foaling are a sudden enlargement of the udder ; sometimes 

 milk may be expressed from the teats ; and when such is 

 the case, provided it does not alarm the mare, she should 

 always be milked ; the vulva protrude, and become vascu- 

 lar ; and when the act has commenced, the tail is erected ; 

 a shyness, a restless shifting and change of place, with 

 some heaving of the flanks and some acceleration of the 

 pulse, are also usually present. The painful contractions 

 of the uterus now call in the aid of the abdominal muscles ; 

 deep inspirations are made, to enable the diaphragm to 

 assist in forcing the uterine contents backwards, by which 

 the mouth of the womb is dilated, and the attachment 

 of the chorion is separated. As the propelhng efforts be- 

 come more violent, the hind legs are set wide apart : the 

 membranes now protrude in the form of a bladder ; which 

 bursting, the liquor amnii floods down, and often brings 

 with it the young one, particularly in large roomy mares, 

 who have had several foalings. At other times the act is 

 more protracted, and the head, \vith the fore legs, are more 

 gradually protruded into the vagina ; when, after several 

 severe efforts, more or less protracted, the foal is born, and 

 its descent to the ground commonly ruptures the umbilical 

 cord ; the afterbirth occasionally accompanies the foal ; 

 and when this is not the case, the whole often comes away 

 very soon after, or may be long and dangerously delayed. 



Lactation. — As soon as the foal comes into the world, it 

 is interesting to observe how soon it begins to suck ; which, 

 however, with a weakly foal, it may occasionally be prudent 

 to assist it in doing, by supporting it to the teats. The 

 first milk, instead of being prejudicial, is beneficial ; as by 

 its purgative qualities it brings away the contents of the 

 foetal alimentary canal. Sometimes the mammae refuse their 

 office, or do not yield sufficient milk ; or a mother may die : 



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