10 BULLETIN 106, U. S. DEPARTMENT OF AGRICULTURE. 



A study of Table 2 illustrates some of the influences which modify 

 the visual signs of the malady. Among the pregnant animals in 

 which the granules were not apparent macroscopically, the fetus 

 exceeded 24 inches in length in about 50 per cent of the cases ; while in 

 the earlier stages of pregnancy the granules were more generally 

 present. Among nonpregnant females the influence of pyometra and 

 recent parturition is very marked. 



Table 1 shows that many young heifers sold as veals escape the 

 infection, while spayed heifers, usually free upon the range, quite 

 generally escape. But the tables tell only a part. It was a very 

 notable phenomenon that the probability of both the presence and 

 intensity of the disease rested vary largely upon the question of 

 copulation. 



The spaying of range heifers is not generally well done. The opera- 

 tion is very carelessly and hastily performed, usually by the flank 

 method, the operator thrusting his hand through the wound, grasping 

 the ovaries and stripping them from the broad ligament between the 

 thumb and fingers. The result is that 50 to 60 per cent of them are 

 only partly spayed, some ovarian tissues are left which develop 

 ovisacs and cysts, the heifers come in estrum or are nymphomaniac, and 

 copulate freely with range bulls. The lesions of the granular venereal 

 disease are uniformly seen in such imperfectly spayed animals, and 

 show considerable intensity. In the perfectly spayed heifers the 

 vulvar mucosa is generally normal, smooth, and pale rose-red, with 

 but few if any visible nodules. 



Another striking illustration of the influence of coitus upon the 

 intensity of the disease was observed in a lot of 270 two-year-old 

 range Hereford heifers which had evidently been kept away from the 

 bull, except in the case of one individual which had, perhaps acci- 

 dentally, become pregnant. In the 269 nonpregnant animals the 

 disease was quite uniformly present, but only a few nodules were 

 seen in each individual. Careful inspection was required lest they 

 be passed over. The vulvar mucosa of the one pregnant heifer, 

 however, bore more of the granules than the other 269 collectively. 

 The entire mucosa was swollen and red, and dense masses of granules 

 crowded thickly upon each other. 



Throughout its long course the intensity of the infection rises and 

 falls, sometimes in obedience to known causes, as copulation, some- 

 times in a manner not yet understood. During the period at which 

 the disease is at its zenith few animals fail to show the clinical 

 evidences of its presence, as is shown by Table 1, according to which 

 the evidences of the disease were apparent in 95 per cent of cases. 

 This is no higher than regularly observed at this age in dairy herds. 



