Lipids and their Role in the Metabolism of Semen 133 



functions of the prostate gland (Hopkins, 1911; Eadie, 1948^, b). 

 They do not seem to occur either in the dog or the rat. The total 

 lipid content of the dog prostatic fluid ranges from 30 to 40 

 mg./lOO ml. (Huggins, 1947) and the lipid phosphorus from M 

 to 2-2 mg. P/100 ml. (Moore et al, 1941). There exists a condition 

 known as the 'benign prostatic hypertrophy', which is common to 

 dog and man. In the dog, however, this condition is not associated 

 with the occurrence of corpora amylacea or any other spheroidal 

 nodules but consists of cystic hyperplasia (Huggins and Clark, 

 1940). In the bull, lipid-laden cells form a highly characteristic 

 component of the seminal vesicle epithelium, and the cavities of 

 the tubules in the seminal vesicles contain an abundance of eosino- 

 philic granular secretion (Mann, Davies and Humphrey, 1949). The 

 extent to which organs other than the seminal vesicle and prostate, 

 contribute to the lipid or sterol content of semen, has not been 

 hitherto studied in much detail. In this connection, however, an 

 interesting observation of Ward and Moore (1953) deserves to be 

 mentioned, concerning the occurrence of 7-dehydrocholesterol in 

 the preputial gland and epididymis of rat. 



