World Journal of Zoology 4 (1): 37-41, 2009
ISSN 1817-3098
© IDOSI Publications, 2009
Corresponding Author: Atef I. Saad, Department of Zoology, Faculty of Science, South Valley University, 81528, Aswan, Egypt
37
A Lungworm Nematode from Amphibian Hosts at Aswan Governorate, Egypt
Atef I. Saad, R. Khalifa and N. Mostafa
1 2 1
Department of Zoology, Faculty of Science, South Valley University, Aswan, Egypt
1
Department of Parasitology, Faculty of Medicine, Assiut University, Egypt
2
Abstract: Females of Rhabdias species were obtained from the lungs of the maculated toad Bufo regularis in
Aswan, Egypt. The parasitized protandrous hermaphroditic female was described in details and was compared
with the previously described species from Egypt. The present specimen was characterized by possessing a
swelling cuticle at the anterior end, which extended to the posterior end; having four lips and two teeth; small
buccal capsule; short oesophagus and large egg size. The present authors preferred to stop the identification
of the parasite at the generic level for more studies on its life cycle to obtain males. Also, it was noticed that
a lot of new species of Rhabdias, were described during this decade all over the world based on minor
characters as shape and width of oesophagus in relation to intestine; a character which was found to be
affected and changed by ageing. Currently, authors suggested that those species should be revised on basis
of the life cycle and on the male characters as well as females' characters.
Key words: Rhabdias Bufo Female Parthenogenetic Protandrous Aswan
INTRODUCTION MATERIALS AND METHODS
Family Rhabdiasidae includes about 70 nominal 850 toads were collected by hand and then
species and possessing the alternation of two generations deposited in herpetological bags for transport.
(heterogony) in their life histories. One generation is Animals were killed. Each host was subsequently
hermaphroditic and inhabits the lungs of amphibians and necropsied and the organs were examined for
some reptiles. The other one is gonochoristic and dwells helminths using a stereoscope. Lung worms were
in the hosts' faeces. The comprehensive information on initially placed in saline (0.65%); afterwards they
the development of Rhabdias bufonis (Schrank, 1788) were killed by immersion in hot 70% ethanol and
Stiles and Hassall, 1905 is expanded. In this species, eggs stored in 70% ethanol containing 5% glycerin.
of parasitic hermaphrodites pass from the host lungs into Nematodes were cleared with glycerin in temporary
the intestine, accumulate in colon and, thereafter, are cast preparations. Drawings were made with the aid of a
out of the host organism in faeces. The free-living stages drawing tube. Measurements were given in
develop in the droppings. Larvae from the eggs of micrometers unless otherwise stated. Minimum and
hermaphrodites reach maturity as males and females of maximum limits were given followed by mean value in
gonochoristic generation. The latter give rise to the parentheses. Some photomicrographs were taken from
hermaphroditic generation larvae which develop in unstained fixed specimens. Ault females were deposited
droppings up to the third stage. At this stage the larvae in the Department of Zoology, Faculty of Science, Aswan
become infective and are able to continue development and the Department of Parasitology, Faculty of Medicine,
only after the penetration into the host [1-2]. Fifty-nine Assiut, Egypt.
Rhabdias species have been described; thirteen of them
were distributed on Ethiopian, Nearctic, Neotropical, RESULTS
Oriental and Palearctic realms were described in recent
years [3-4]. There are few studies dealing with parasites of The present species was collected from the lungs of
amphibians and reptiles in Egypt [5-8]. During this study the maculated toad Bufo regularis. All worms were only
a species of Rhabdias was collected from endemic toad females. The percentage of infection was 25.9% (220
from Aswan as part of a biodiversity inventory of of 850 specimens) and the worm burden was 1-6 per
parasites of amphibians. host.