11 



pure bred animals, in all probability some have been omitted. The* 

 records show that nearly all were acquired by gifts from friends of 

 the college although a few were bought. 



Within the time mentioned at least fifty pure bred bovines were 

 acquired and owned by the college together with some twenty 

 lots of other domestic animals consisting of sheep, swine and horses. 

 These animals were collected from three different countries, eight or 

 nine states, about fifty towns, and can be traced to at least fifty 

 separate herds. In most instances, only the herds are referred to in 

 which the animals were, immediately before coming into the posses- 

 sion of the college. Taking into consideration the history of the pure- 

 bred stock that may have been omitted, together with the grade 

 animals that were frequently added to the herd, it would lie safe to- 

 estimate that about seventy-five towns and one hundred herds were 

 represented in the college herd during the twenty-seven years between 

 the acquisition of the fii'st two bull calves and the last animals 

 purchased. 



Without doubt many of the pure bred cattle came from old estab- 

 lished herds which were kept in close warm stables and were forced 

 to the production of large quantities of milk, in fact were kept under 

 the conditions favorable to the development of tuberculosis. 



The course pursued in the early days of the college for the collec- 

 tion of a herd was decidedly bad, viewing the subject from the 

 standpoint of to day and knowing what we now do of the causes,- 

 spread and propagation of the infectious diseases of animals. For 

 it has been repeatedly demonstrated that all contagious diseases of 

 both men and animals are the most common along the lines of traffic 

 and also when persons and animals are collected together in large 

 numbers or when there is frequent change of location. These condi- 

 tions are most favorable for the existence and rapid spread of the 

 infectious material which gives rise to this class of diseases. That 

 this was the case with the herd under consideration appears in the 

 study of tuberculosis in the college herd. 



The first knowledge that we have of the existence of tuberculosis 

 in the college herd dates back to about the year 1871 . At that time- 

 a fat cow was sold to a butcher in North Amherst and at the time of 

 slaughter it was found that the pleural surface of the thorax was- 

 thickly studded with large and small nodular growths, some of whicL 

 were filled with pus and others with caseous or calcareous material. 

 The true nature of these excrescences was not recognized. No one- 



