The Diseases and Parasites of Wild Ruffed Grouse 241 

 Ptychostoma bonasae Tyzzer, 1930 



Cyathosoina striatum Tyzzer, 1930 



These tliree (possibly four) species of flagellates have been de- 

 scribed from the ruffed grouse. In no instance have they shown any 

 indication that they might be seriously pathogenic. They apparently 

 are a normal part of the bird's internal fauna and are not associ- 

 ated with any disease. They were found in a large proportion of 

 the birds examined by Dr. Tyzzer and reported upon by Allen and 

 Gross ( 1926 ) . These flagellates they mentioned were probably the 

 species later described by Tyzzer ( 1930 ) . Clarke ( 1936 ) reported 

 four birds from Ontario lightly infected with a flagellate tentatively 

 identified as Trypanosoma gallinarum. He noted that the organism 

 is probably more prevalent than would be indicated by the small 

 number of cases, a suggestion borne out by the prevalence reported 

 by Tyzzer, yet passing unnoticed in several other reports on grouse 

 parasites. Fisher (1939) reported one grouse from Michigan con- 

 taining flagellates of the genus Trypanosoma, identified by Stafseth 

 and Kotlan. 



Tyzzer ( 1930 ) found the two parasites he described as prevailing 

 in the ceca, over the surface of the mucosa, and occasionally found 

 in the contents of the large intestine. It appeared that of the two, 

 Ptychostoma was preponderant near the outlet of the cecum while 

 Cyathosoma occurred in the dilated portions. He noted that they 

 may be in ". . . the nature of symbionts essential to the health of 

 the mature bird . . ." but this is merely a conjecture. 



Histomonas m^eleagridis ( Smith, 1895 ) Tyzzer, 1920. This protozoan 

 is the organism that causes the disease known as "blackhead," a 

 scourge of the domestic turkey. It is a common cause of death of 

 grouse in captivity (Allen and Gross, 1926; N. Y. S. Cons. Dept. Ann. 

 Reports, 1933-42) but has not definitely been identified in wild 

 grouse. Even though this chapter intends only to cover the diseases 

 of wild grouse, this organism is included because of the great proba- 

 bility that it actually does affect the wfld birds when they come into 

 contact with poultry range. The action of the disease is so rapid that 

 infected specimens in the wild would be exceedingly difficult to 

 obtain. 



Any poultry range is apt to be infected with blackhead even 

 though the chickens or turkeys themselves do not show signs of 



