98 VEGETABLE PARASITES. 



VII. Thrush in Poultry. 



Two known cases of ' Thrush ' in Poultry are the 

 only records w r e have ; these were observed by E berth 

 and Martin, and are recorded respectively in ' Vir- 

 chow's Archiv/ iii. p. 528, and in l Jahresber. d. 

 Thierarznei-Schule in Mtinchen,' 1882-3, p. 125. 



Many cases of so-called 'Thrush' in fowls have 

 been mistaken instances, the true cause of the white 

 creamy growths being the Sporozoa, &c, described 

 in the article on Diphtheria (p. 4). True 'Thrush' 

 is due to a fungus known as Saccliaromyces albicans. 

 These two instances recorded were found on exami- 

 nation to be due to the same fungus that is found in 

 the ' Thrush ' of children and calves. There were 

 found in the fowl examined by Eberth several white 

 deposits adhering to the mucous membrane of the oeso- 

 phagus, similar in external appearance to those found 

 in children. These two cases are interesting, but 

 of little practical importance, as Thrush appears not 

 only to be rare but not to attack healthy birds. 



These are the only three groups of vegetable 

 parasites known to me as affecting Fowls. 



Bacilli. 

 Bacilli, although sometimes regarded as belonging 

 to the vegetable kingdom, have such unique charac- 

 ters, both pathologically and physiologically, that 

 they are best separated as a distinct group of disease- 

 producing forms of life. Hence Fowl Cholera &c. 

 are not dealt with in this Manual. 



