Studies on Oxyspirura mansoni, the Tropical Eyeworm 
of Poultry. II. Life History 
Calvin W, Schwabe^ 
This paper, the second in a series, presents 
the results of a study made in Hawaii of the 
life history of Oxyspirura mansoni, the tropical 
eyeworm of poultry. This nematode has been 
shown by previous investigators to possess a 
digenetic life cycle in which it utilizes as the 
definitive host many species of domestic and 
wild birds and, as the secondary host, a single 
species of burrowing cockroach, Pycnoscelus 
surinamensis. 
The parasite is widely distributed in the 
warmer parts of the world. It has been re- 
ported from Brazil (de Magalhaes, 1888; 
Almeida, 1933), China (Cobbold, 1880), 
Indo-China (Fielding, 1928^), Mauritius 
(Emmerez and Megnin, 1901), Reunion 
(Ozoux, 1910), British West Indies (Hutson, 
1943), Formosa (Kobayashi, 1927), British 
and Dutch East Indies (Picard, 1929; Field- 
ing, 1928^), Florida and Jamaica (Ransom, 
1904), Hawaii (Wilcox and McClelland, 
1913), Guam (Fielding, 1928^), and Samoa 
(Alicata, personal communication). Its near 
relative (or synonym), Oxyspirura parvovum, 
has been reported from Australia by Dodd 
(1909). 
Apparently Manson’s eyeworm has ap- 
proximately the same circumtropical distri- 
bution as its intermediate host (reviewed in 
Schwabe, 1949). Neither parasite nor host is 
known to exist in Hawaii at altitudes exceed- 
ing 3,000 feet. 
^Department of Zoology and Entomology, Univer- 
sity of Hawaii. Present address: Department of Bac- 
teriology, School of Veterinary Medicine, Alabama 
Polytechnic Institute, Auburn, Alabama. Manuscript 
received May 16, 1950. 
The eyeworm is considered important eco- 
nomically in many tropical and subtropical 
areas. The roach is objectionable not only in 
that it serves as the vector for the eyeworm, 
but also because it reportedly damages both 
roots and bark of certain ornamental and crop 
plants (reviewed by Schwabe, 1949) • Previous 
to this study the development of the larval 
and adult stages of this parasite was not well 
known. 
MATERIALS AND METHODS 
Surinam roaches in all stages of develop- 
ment were easily collected from soil beneath 
chicken houses and in chicken yards. Because 
the incidence of natural infection with the 
parasite among such roaches approached 100 
per cent, only laboratory-raised nymphs were 
employed in the experimental infections. 
Adult Pycnoscelus surinamensis females were 
housed individually in 4-inch glass stacking 
dishes. A 3 -inch disk of filter paper was placed 
in each dish to provide a hiding place for the 
roaches during the daytime. Nymphs, iso- 
lated at birth, were housed together in the 
same manner as the adults. The roaches 
thrived on a diet of whole-wheat bread and 
water. 
Embryonated eggs for infecting laboratory- 
raised roaches were obtained by macerating 
gravid female worms. This procedure proved 
more satisfactory than the involved method 
of concentration and separation of embryo- 
nated eggs from the feces of infected birds. 
The gravid worms were taken from the eyes 
of infected chickens obtained from poultry 
farms in Manoa Valley and Waialae, Hono- 
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