DISEASES OF CATTLE 157 



probably have disclosed an imperfectly formed ovary incapable of 

 bringing ova to maturity. 



A bull and cow that have been too closely inbred in the same line 

 for generations may prove sexually incompatible and unable to gen- 

 erate together, though both are abundantly prolific when coupled 

 with animals of other strains of blood. 



Finally a bull may prove unable to get stock, not from any lack 

 of sexual development, but from disease of other organs (back, loins, 

 hind limbs), which renders him unable to mount with the energy 

 requisite to the perfect service. 



CONGESTION AND INFLAMMATION OP THE TESTICLES (ORCHITIS). 



This usually results from blows or other direct injuries, but may 

 be the result of excessive service or of the formation of some new 

 growth (tumor) in the gland tissue. The bull moves stiffly, with 

 straddling gait, and the right or left half of the scrotum in which the 

 affected testicle lies is swollen, red, and tender, and the gland is 

 drawn up within the sac and dropped down again at frequent inter- 

 vals. It may be treated by rest; by 1^ pounds Epsom salts given in 

 4 quarts of water; by a restricted diet of some succulent food; by 

 continued fomentations with warm water by means of sponges or 

 rags sustained by a sling passed around the loins and back between 

 the hind legs. The pain may be allayed by smearing with a solution 

 of opium or of extract of belladonna. Should a soft point appear, in- 

 dicating the formation of matter, it may be opened with a sharp 

 lancet and the wound treated daily with a solution of a teaspoonful 

 of carbolic acid in a half pint of water. Usually, however, when the 

 inflammation has proceeded to this extent the gland will be ruined 

 for purposes of procreation and must be cut out. (See "Castration") . 



INFLAMMATION OF THE SHEATH. 



While this may occur in bulls from infection during copulation 

 and from bruises, blows, and other mechanical injuries, the condition 

 is more common in the ox in connection with the comparative inac- 

 tivity of the parts. The sheath has a very small external opening, 

 the mucous membrane of which is studded with sebaceous glands 

 secreting a thick, unctuous matter of a strong, heavy odor. Behind 

 this orifice is a distinct pouch, in which this unctuous matter is liable 

 to accumulate when the penis is habitually drawn back. Moreover, 

 the sheath has two muscles (protractors) which lengthen it passing 

 into it from the region of the navel, and two (retractors) that shorten 

 it passing into it from the lower surface of the pelvic bones above. 

 The protractors keep the sheath stretched so that it habitually covers 

 the penis, while the retractors shorten it up in the act of service, so 

 that the penis can project to its full extent. In stud bulls the fre- 

 quent protrusion of the erect and enlarged penis and the retraction 

 and dilatation of the opening of the sheath serve to empty the pouch 

 and prevent any accumulation of sebaceous matter or urine. In the 

 ox, on the other hand, the undeveloped and inactive penis is usually 

 drawn back so as to leave the anterior preputial pouch empty, so that 

 the sebaceous matter has space to accumulate and is never expelled 

 by the active retraction of the sheath and protrusion of the erect penis 



