54 



INTERNAL SECRETIONS OF THE OVARY 



copulation, and, as originally shown by Heape (288) in the 

 rabbit, and Marshall (441) in the ferret, ovulation is dependent 

 upon copulation. Both animals have a well-developed pseudo- 

 pregnant period after sterile copulation, during which the ovary, 

 uterus, and mammary glands undergo growth similar to that 

 found during at least the first half of pregnancy. 



.^ 





■'-.^■i.'i^^fV'r 



Fig. 27. — Uterus of Pseudo-Pregnant Rabbit. 

 The stromal glands are greatly developed. 



Rabbit. The histological and physiological changes occurring 

 during the fertile cycle of the rabbit have been extensively 

 studied by Ancel and Bouin (27, 29, 30-4, 75-7) and by Ham- 

 mond (264). The changes which take place are very marked in 

 the uterus, ovaries, and mammary glands. The vaginal cycle is 

 less clear, though changes have been described by Tsu (617) and 

 Courrier (139). Since oestrus is persistent, the only cycle is that 

 of anoestrus, oestrus, pregnancy, and lactation. If the animal 

 becomes pregnant at the beginning of the breeding season a 

 condition of cestrus will reappear immediately after parturition 

 and will continue during lactation. Pregnancy, however, does 

 not usually occur during lactation, as the blastocysts fail to 



