VII. The Reproductive processes of certain mammals. Part VII. - Seasonal variation in the reproductive organs of the male hedgehog

Abstract

The seasonal changes in the genital tract of the male hedgehog, notably the enormous hypertrophy of the accessory sexual glands in the spring and summer, early attracted the attention of biologists. The first important account of the reproductive cycle was given by Marshall (1911) who described the histological condition of the testis at different seasons and found that the production of spermatozoa commenced as early as January and continued to the end of September. The summer and winter appearance of the prostate and Cowper’s glands was described by Griffiths (1890), and in 1926 Pellegrini published observations on the secretory cycle in the interstitial cells of the testis. Courrier (1927) studied the cyclic changes in the various organs and gave a full bibliography of work on the male hedgehog. Animals with restricted reproductive activity have already proved valuable for experimental research (Hill and Parkes, 1932 ; Bissonnette, 1932), and earlier workers recognized the suitability of the hedgehog in this connection. Marshall (1911), by castrating hedgehogs at various phases of the reproductive cycle, showed that the periodic hypertrophy and continued activity of the accessory glands was controlled by the testes, and Courrier extended and confirmed his findings. The hedgehog should prove useful in a wide range of experimental work, for, besides possessing remarkable accessory glands, it is probably the only mammal with abdominal testes that can be easily obtained in England and kept in captivity. Although the general nature of the reproductive cycle has been described, previous authors have been content to examine a few animals only, and it was therefore thought desirable to examine a series sufficiently large to provide an adequate quantitative basis for experimental work. In addition, the large number of immature animals obtained supplied information on the rate of development of the genital tract before the first breeding season.