222 Bulletin 158. 



is a direct cause." Thus he has pointed out that "certain tracts 

 of the country are not suited to the manufacture of cheese as the 

 excess of certain salts in the soil which are taken up in unusually 

 large quantities b}^ the forage plants, tend to produce a con- 

 tinuous looseness of the bowels." It is well known to American 

 cheese buyers that the most desirable flavors are not found in 

 cheese made from the milk of cattle pastured on certain swampy 

 or new lands. The cause here, is due to the tainting of the milk 

 through the physiologic effect of certain of the plants eaten by 

 the cattle. A familiar analogous illustration is found in the well 

 known flavors imparted to the milk and butter when cattle are 

 fed upon turnips or grazed in a pasture where wild onions are 

 abundant. 



Some dairymen in this country believe that the trouble is 

 attributable to certain abnormal conditions attending parturition. 

 This is based on the observation that frequently, if not always, a 

 few cows in one or more of the dairies furnishing milk to the 

 troubled factory retain the placenta or afterbirth at the time of 

 parturition, and that the conditions thus brought about, cause 

 the subsequent odors in the curd made from the milk. 



The painstaking investigations of Russell indicate that the 

 cause of the particular odors and flavors in question are of bac- 

 terial origin, and that they have nothing in common with those 

 due to volatile or other substances in the food. Guillebeau has 

 found a close relation existing between the bacteria that are able 

 to produce an infectious mammitis and some forms capable of 

 gas evolution. Several times "gassy" milk has been traced 

 directl}' to animals suffering, from an acute inflammation of the 

 udder in which it has been affirmed that the organisms producing 

 the disease were a direct cause of the gas production in the milk. 

 Guillebeau* found three bacilli which he believed to be the cause 

 of inflammation of the udder, and which possessed the power of 

 causing a well marked cavernous structure in the cheese. 



In the summer of 1897, an opportunity arose to inquire into 

 the cause of ' ' gassy ' ' curds and taints in a factory receiving 

 milk from a dairv in which there had been considerable trouble 



* Quoted by von Freudenreich. Dairy Bacteriology, page 57, EngUsh 

 translation bv Davis. 



