DISEASES OF THE GENERATIVE ORGANS. 173 



retained witliiii tlie iilxloiiu'ii ; (A) inllaiiinialion of the testicles, re- 

 sulting in induration; (c) tatty defeneration of tlie testicles, in stal- 

 lions liberally fed on starchy feed and not sufficiently exercised; (d) 

 fatty degeneration of the excretory duets of the testicles {ruj^a dtfe- 

 renthi): (< ) inllannnation or ulceration of these (hicts; (/) intlani- 

 mation or ulceration of the nuicous nienihrane covering the penis; 

 {(j) injui'ies to the })enis from blows (often causing paralysis) ; (h) 

 uarty growths on the end of the penis; (/) tumors of other kinds 

 (largely pigmentary), affecting the testicles or penis; {j) nervous 

 diseases "which abolish the sexual appetite or that control the museles 

 which are essential to the act of coition; (/. ) azoturia with resulting 

 weakness or paralysis of the nniscles of the loins or the front of the 

 thigh (above the stifle) ; {I) ossification (anchylosis) of the joints 

 «d' the back or loins, which render the auinuil unable to rear or 

 inount; {m) spavins, ringbones, or other painful ati'ections of the 

 hind limbs, the pain of which in mounting causes the animal to sur- 

 denly stop short in the act. In the first three of these only (a, 6, 

 and c) is there real sterility in the sense of the nondevelopment or 

 impei-fect de\elo])ment of the male vivifying eleuient (spermatozoa). 

 In the other examples the secretion may be imperfect in kind and 

 amount, but as copulation is prevented it can not reach and imj^reg- 

 nate the ovum. 



In the mare barrenness is e(jually ilue to a variety of cause's. In 

 a number of breeding studs the proportion of sterile mares has 

 \ aried from I'O to 40 per cent. It may be due to : {a) Imperfect 

 develoi)ment of the ovary and nomnaturation of ova; {h) cystic 

 or other tumors of the ovary; {c) fatty degeneration of the ovary 

 in very obese, paujpered mares; {d) fatty degeneration of the excre- 

 tory tubes of the ovaries (Fallopian tubes) ; {c) catarrh of the womb, 

 with mucopurulent discharge; (/) irritable condition of the womb, 

 with profuse secretion, straining, and ejection of the semen; {y) 

 nervous irritability, leading to the same expulsion of the male ele- 

 ment; {h) high ccmdition (plethora), with profuse secretion and 

 excitement; (/) low condition, with imperfect maturation of the 

 (ua and lack of sexual desire; {)) poor feeding, overwork, and 

 chronic debilitating diseases, as leading to the condition just nauied; 

 (A) closure of the neck of the womb, temporarily by spasm or per- 

 manently by inllammatiijii and induration; (/) closure of the en- 

 trance to the vagina through imperforate hymen, a rare, though not 

 unknown, condition in the mare; (m,) acquired indisposition to breed, 

 seen in old, hard-worked mares which are first put to the stallion 

 when aged; in) change of climate has repeatedly been followed l)v 

 barrenness; (o) hybridity. which in male and feuiale alike usually 

 entails sterilitv. 



