102 



THE TRICHOMONADS 



the mere presence of an organism in a 

 lesion is no proof that it caused the lesion. 

 There is no satisfactory proof that T. gal- 

 liiutru))! by itself is capable of causing 

 disease, and the weight of evidence is 

 against it. Delappe (1957) infected chick- 

 ens and turkeys experimentally with a 

 strain of T. galliiianiDi isolated from 

 liver lesions of a turkey with histomonosis, 

 but was unable to produce either symptoms 

 or lesions. The possibility has still not 

 been completely eliminated, however, that 

 a Penlalrichomonas may exist which is 

 pathogenic (see below). 



Epidemiology: Birds become infected 

 by ingestion of trichomonads in contamin- 

 ated water or feed. McLoughlin (1957) 

 found that one-week-old turkey poults were 

 more susceptible than 9-week-old ones. 

 He also found that T. gcilliiiarnni survived 

 for 24 hours but not for 48 hours in cecal 

 droppings at 37" C, and for 120 hours at 

 6' C. 



Cultivation : T. gnlUnanuv is readily 

 cultivated in the usual trichomonad media. 



TRICHOMONAS ANATIS 

 (KOTLAN, 1923) 



Synonym : Tetratrichomonas anatis. 



Host : Domestic duck. 



Location : Posterior part of intes- 

 tinal tract. 



Geographic Distribution : Europe 

 (Hungary). 



Morphology : The body is broadly 

 beet-shaped, 13 to 27 by 8 to 18 fx, with 4 

 anterior flagella, an undulating membrane 

 extending most of the length of the body, a 

 free trailing flagellum, a costa and a 

 fibrillar axostyle. 



TRICHOMONAS ANSERI 

 HEG^fER, 1929 



Hosts : Domestic goose, baby chick 

 (experimental). 



Morphology : The body is oval, 6 to 

 9 by 3. 5 to 6. 5(i with a mean of 8 by 5jx . 

 Four anterior flagella appear to arise in 

 pairs from 2 blepharoplasts. The undulat- 

 ing membrane extends almost the full 

 length of the body. A free trailing flagel- 

 lum and a costa are present. The axo- 

 style is broad and hyaline, extending a 

 considerable distance beyond the body. 

 There is no chromatic ring at its point of 

 emergence from the body. The nucleus is 

 characteristic, completely filled with min- 

 ute chromatin granules and also with a 

 single large karyosome usually at one 

 side. The cytostome is prominent. Many 

 specimens have large bacteria in the en- 

 doplasm. 



Location : Ceca. 



Geographic Distribution : United 

 States (Maryland). 



Prevalence : Unknown. 



Remarks : Hegner (1929) found a very 

 few of these trichomonads in cecal material 

 from a goose. He inoculated 3-day-old 

 chicks with the material /»(?r os and per 

 rectimi and the above description is based 

 on material from the chicks. 



OTHER SPECIES OF TRICHOMONAS 



Trichomonas macacovaginae Hegner 

 and Ratcliffe, 1927 occurs in the vagina 

 of the rhesus monkey. It measures 8 to 16 

 by 3 to 6 ^ and has a free posterior flagel- 

 lum, a feature which differentiates it from 

 T. vaginalis. 



T. w^/cro// Wenrich and Saxe, 1950 

 occurs in the cecum of the Norway rat, 

 house mouse, goldfen hamster, vole {Mi- 

 croliis peniisylL'a)iici<s) and other wild ro- 

 dents. It is 4 to 9 ji long. Simitch, Petro- 

 vitch and Lepech (1954) transmitted it from 

 the white mouse to the laboratory rat, guin- 

 ea pig, ground squirrel (Citellus citelliis), 

 dog and cat, but were unable to infect the 

 chicken and a human volunteer. Wenrich 

 and Saxe (1950) transmitted if from the vole 

 to the laboratory rat, hamster and guinea 

 pig, but could not infect a human volunteer. 



