274 



PIASMODIUM. HAEMOPROTEUS AND LEUCOCYTOZOON 



of wild ducks, geese and swans, including 

 the Canada goose, whistling swan, wood 

 duck, pintail, green-winged teal, Aus- 

 tralian teal, blue-winged teal, mallard, 

 black duck, white-winged duck, cotton teal, 

 Australian sheldrake, wattle duck, shov- 

 eller, Baer's pochard, ring-necked duck, 

 white-eyed duck, rufous -crested duck, 

 baldpate, common goldeneye, surf scoter, 

 old squaw and common merganser (Levine 

 and Hanson, 1953; Herman, 1954; Fallis 

 and Wood, 1957). 



infected birds is 14 to 21 days. Schizogony 

 has not been described, and the details of 

 sporogony in the midge are still to be 

 worked out. Fallis and Wood found ooki- 

 netes in the midge stomach 36 hours after 

 ingestion; they found structures which they 

 regarded as oocysts on the stomach wall, 

 and other structures which they regarded 

 as sporozoites in the salivary glands. 



Pathogenesis : H. nettionis is only 

 slightly if at all pathogenic. 



Location : The gametocytes are in 

 the erythrocytes. Schizogony occurs in 

 the endothelial cells of the blood vessels. 



HAEMOPROTEUS MELEAGRIDIS 

 N. SP. 



Geographic Distribution: Worldwide. 



Hosts : Domestic and wild turkey. 



Prevalence : Common. This species 

 is a parasite of wild waterfowl which may 

 infect domestic ducks in heavily endemic 

 regions. 



Morphology : Only the sexual stages 

 are found in the red blood cells. Except 

 early in an infection, young stages are 

 absent or rare. The mature macroga- 

 metes and microgametocytes are elongate 

 and sausage-shaped, partially (or some- 

 times completely) encircling the host cell 

 nucleus, often displacing it. There is fre- 

 quently a narrow band of cytoplasm be- 

 tween the parasite and the host cell nucleus, 

 Free macrogametes and microgametocytes 

 may occasionally be found; these are usu- 

 ally round. The macrogametes and micro- 

 gametocytes contain a few to 30 or more 

 (usually 12 to 24) pigment granules which 

 are usually coarse and round and tend to 

 be grouped at the ends of the cell. The 

 host cell is not enlarged. 



When stained with a Romanowsky 

 stain, the cytoplasm of the microgameto- 

 cytes is pale blue or almost colorless and 

 their nuclei are pale pink and diffuse, 

 while the cytoplasm of the macrogametes 

 is darker blue and their nuclei are com- 

 pact and dark pink or red. 



Life Cycle : The vector of H. nettionis 

 was first discovered by Fallis and Wood 

 (1957). It is the biting midge, Cidicoides. 

 The prepatent period in experimentally 



Location : The gametocytes are in 

 the erythrocytes. 



Geographic Distribution : North 

 America. 



Prevalence : Uncommon. Haemo- 

 proteus sp. was reported from 1 out of 4 

 domestic turkeys in the District of Colum- 

 bia and vicinity by Wetmore (1941), from 

 a turkey poult from Texas by Morehouse 

 (1945), from 5 of 97 eastern wild turkeys 

 (of which 4 had been reared in captivity) 

 in Pennsylvania by Kozicky (1948), from a 

 flock of turkeys in North Dakota by Goldsby 

 (1951), from 3 out of 10 turkeys in South 

 Carolina by Atchley (1951), from 1 out of 

 2 wild turkeys in Georgia by Love, Wilkin 

 and Goodwin (1953) and from 42% of 52 

 birds in a flock of domestic turkeys in 

 South Carolina by Bierer, Vickers and 

 Thomas (1959). 



Morphology : Only Morehouse (1945) 

 described the macrogametes and micro- 

 gametocytes. They are elongate, sausage- 

 shaped, curve around the host cell nucleus 

 and occupy about 1 2 to 3 4 of the host cell. 

 Their surface is usually in close contact 

 both with the host cell nucleus and host cell 

 wall. The macrogametes measure 14 to 

 19 by 2 to 4 ^ with a mean of 17 by 3 fi . 

 They contain 18 to 48 (mean, 27) round or 

 irregular pigment granules. Their nuclei 

 measure 2 to 6 by 2 to 3 fx with a mean of 

 4 by 2(i and are ovoid or irregular in shape. 



