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Two new species of habronematid nematodes are described in birds from the Area de Conservacion Guanacaste, Costa Rica. Torquatoides trogoni n. sp., in Trogon massena, can be distinguished from T. torquata, T. bengalensis, and T. crotophaga in lacking lateral alae. Among species lacking lateral alae, the new species differs from T. balanocephala in having 14 versus 8-10 cephalic cuticular plaques, 21-22 versus 13-17 pairs of preanal papillae, and a beak-shaped versus U-shaped gubernaculum. The new species differs from T. singhi in body length, in having 21-22 versus 10 pairs of precloacal papillae, longer spicules, and larger eggs. The new species differs from T. crotophaga, the only other species known from Central America, in lacking lateral alae, and having 14 versus 6 cephalic cuticular plaques, 21-22 versus 17 pairs of precloacal and 3 versus 2 pairs of postcloacal papillae, and a gubernaculum. Excisa ramphastina n. sp., in Ramphastos sulfuratus, can be distinguished from E. excisa, E. biloba, E. buckleyi, E. dentifera, and E. khalili in having 1 lateral ala versus none, cervical papillae anterior versus posterior to the nerve ring, and asymmetrical caudal alae. Excisa ramphastina is similar to E. curvata in having cervical papillae anterior to the nerve ring but differs in having 1 lateral ala versus none, asymmetrical caudal alae, an average spicule ratio of 1:4.4 versus 1:3.3, and 4 versus 2 pairs of sessile papillae. The new species differs from E. columbi in having 1 versus 2 lateral alae, in the length of the spicules, in having a different spicule ratio, and in the numbers of sessile papillae.  相似文献   

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Breeding birds in the tropical rain forests of Kibale National Park, Uganda   总被引:2,自引:0,他引:2  
A combination of trapping and foot surveys was used to assess the breeding status of birds in unlogged and logged sites in the tropical rain forest of Kibale National Park, Uganda. Breeding of forest edge and gap species was greatly enhanced by logging, whereas crevice and hole nesting specialist breeders were adversely affected. Egg‐laying periods corresponded to higher rainfall regimes at the nearby field station. The relevance of these findings to bird conservation is discussed.  相似文献   

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Cyathostoma lari Blanchard, 1849 is a nematode which parasitizes the orbital and nasal cavities of gulls (Laridae), the crow family (Corvidae) and occasionally other species of birds. It has not, apparently, been reported in birds of prey, although two other species, C. americana and C. brodskii , have been recorded in the air sacs of raptors in North America and the USSR.
This report describes infection by nematodes, provisionally identified as C. lari , in the orbital cavities of two kestrels ( Falco unnunculus ) and a common buzzard ( Buteo buteo ). A single specimen was also recorded in the lower eyelid of a sparrowhawk ( Accipiter nisus ). There was no evidence of pathogenicity in the kestrels and buzzard, but in the sparrowhawk the parasite was possibly associated with damage to the eyelid.  相似文献   

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A postmortem survey of 57 horses in tropical northern Queensland revealed 41 (89%) infected with intestinal strongyles. Thirty-five strongyle species (8 large strongyles and 27 small strongyles [Cyathostominae]) were recorded of which 9 species are reported from Australia for the first time. The 14 most prevalent small strongyles were Cyathostomum catinatum (in 76% of horses), Cyathostomum coronatum (65%), Cyathostomum pateratum (33%), Cyathostomum labiatum (30%), Cylicostephanus calicatus (70%), Cylicostephanus longibursatus (67%), Cylicostephanus goldi (43%), Cylicostephanus minutus (26%), Cylicocylus nassatus (67%), Cylicocyclus leptostomus (41%), Cylicocylus insigne (41%), Cylicocyclus radiatus (33%), Cylicocyclus brevicapsulates (22%), and Poteriostomum imperidentum (24%). The remaining cyathostomes were each found in less than 15% of horses. The 4 most common large strongyles were Triodontophorus serratus (30%), Strongylus vulgaris (28%), Strongylus equinus, and Strongylus edentatus (both 22%). The number of species of small strongyles per horse showed a marked variation (mean 10.3, range 2-21) but bore no relationship to either the total number of strongyles per horse, age, sex, and breed of horse, or season. Total number of strongyles per horse (mean 15,890, range 20-165,000) was less than in recent surveys in Europe and the U.S.A. Most horses had low worm burdens, whereas a very small number were heavily infected. Ninety-seven per cent of the total strongyle counts were small strongyles. Strongylus species contributed just over 1%. Small numbers of large strongyles per horse were usual with T. serratus (mean 570), S. vulgaris (mean 330), and S. equinus (mean 330) the most numerous.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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The pathology induced by the nematode Camallanus cotti in the aquarium fishes Beta splendens (beta fish) and Poecilia reticulata (guppy) consisted of gross and microscopic lesions, the former characterized by abdominal swelling with reddish parasites protruding from the anus in both fish hosts and the latter, similar in the beta fishes and guppies, by hemorrhage, congestion, edema, a few glandular elements, and extensive erosion areas in the rectum mucosa, with a marked thickening of the wall and absence of inflammatory infiltrate. Lesions were associated with the presence of several worms attached to the wall or free in the rectal lumen. This is the second reference of the parasite in Brazil and the first report of pathological findings related to this nematode species that is also briefly redescribed and illustrated for the first time on the basis of Brazilian samples.  相似文献   

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A new species of Parahadjelia occurs in the muscovy duck, Cairina moschata (Linnaeus, 1758), from the Area de Conservacion Guanacaste, Costa Rica. The new species differs from Parhadjelia neglecta Lent and Freitas, 1939, in the body size, in the spicules shape and ratio of spicules, and in having 2 pairs of sessile papillae near the tail tip of the male. The characters exhibited by P. neglecta and the new species validate its generic status distinct from Hadjelia.  相似文献   

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In 1991, a vasectomy program was initiated at the Wildlife Conservation Park/Bronx Zoo to minimize the population growth of resident Canada geese (Branta canadensis). Sixty‐nine males were vasectomized over a 6‐year period. From 1994 to 1998, egg fertility was examined in females paired with vasectomized and non‐vasectomized geese. Of the 340 eggs laid by females paired with vasectomized males, 12% were fertile. In comparsion, of the 526 eggs laid by females paired with non‐vasectomized males, 90% were fertile. The vasectomy procedure was easier to perform on males captured during the breeding season than on those captured during molt owing to the enlarged size of the vas deferens. Where resident Canada goose populations are small and resources available, the implementation of a vasectomy program can be effective in reducing population growth. Zoo Biol 19:35–40, 2000. © 2000 Wiley‐Liss, Inc.  相似文献   

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Ventral cord and vulva development are analyzed in a large sample of nematode species of the suborder Cephalobina. We find a specific range of evolutionary variations at distinct developmental steps. (1) Unlike Caenorhabditis elegans and relatives, the vulva is formed from the four precursor cells P(5-8).p or, exceptionally, from P(6, 7).p only. (2) The vulval competence group is restricted to these four cells or is larger. (3) The fates of more anterior and posterior Pn.p cells vary between closely related species (mostly cell death versus epidermal fate). (4) The mechanism of vulval cell fate patterning varies within a single genus, even between strains of the same species. (5) We describe the first example of a vulval cell lineage that is asymmetric between the anterior and the posterior sides of the vulva. For a selection of the investigated taxa, phylogenetic trees were constructed in order to map vulval characters and infer evolutionary polarities. We can conclude that in this group, death of the Pn.p cells probably constitutes a derived character state compared to a syncytial fate. Rhabditophanes sp. and Strongyloides ratti are placed as sister taxa, probably sharing an exclusive common ancestor in which the number of precursor cells forming the vulva was reduced from four to two.  相似文献   

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The bonobo, Pan paniscus, is one of the most endangered primate species. In the context of the Bonobo Species Survival Plan®, the Milwaukee County Zoo established a successful breeding group. Although the bonobo serves as a model species for human evolution, no prenatal growth curves are available. To develop growth graphs, the animals at the Milwaukee County Zoo were trained by positive reinforcement to allow for ultrasound exams without restraint. With this method, the well being of mother and fetus were maintained and ultrasound exams could be performed frequently. The ovulation date of the four animals in the study was determined exactly so that gestational age was known for each examination. Measurements of biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femur length (FL) were used to create growth curves. Prenatal growth of P. paniscus was compared with the data of humans and the common chimpanzee, P. troglodytes. With respect to cranial structures, such as BPD and HC, humans have significant acceleration of growth compared with P. paniscus and P. troglodytes. In P. paniscus, growth of AC was similar to HC throughout pregnancy, whereas in humans AC only reaches the level of HC close to term. Growth rate of FL was similar in humans and the two Pan species until near day 180 post‐ovulation. After that, the Pan species FL growth slowed compared with human FL. The newly developed fetal growth curves of P. paniscus will assist in monitoring prenatal development and predicting birth dates of this highly endangered species. Zoo Biol 30:241–253, 2011. © 2010 Wiley‐Liss, Inc.  相似文献   

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Spermatogenesis of five rhabditid nematodes was studied using transmission electron microscopy and is described herein. Structure and development of nematode sperm in all available representatives of the extensive order Rhabditida have been analysed and the main characteristics of each infraorder are discussed. The ancestral sperm of the order Rhabditida was reconstructed using maximum likelihood and Bayesian methods based on 44 ultrastructural sperm characters. The hypothetical ancestral spermatogenesis of the order Rhabditida agrees with the previously suggested “rhabditid” pattern and appears to be conserved throughout the order Rhabditida. Despite the enormous variation of rhabditid nematodes, few groups deviate from the ancestral pattern. This conserved pattern can be informative within the phylum Nematoda at order level, but poses limitations when used in taxonomic and phylogenetic analysis within Rhabditida.  相似文献   

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Infection and growth rates of the fowl nematode Ascaridia galli were compared in germ-free, conventional, and other gnotobiotic chickens. Uniform experimental infections induced in chickens at 7–12 days of age showed that significantly fewer (P < 0.01) worms established themselves in germ-free chickens than in chickens with conventional flora. Numbers of worms established in monoassociated hosts (Bacillus subtilis, B. cereus, and Penicillium sp.) were intermediate between those in grossly contaminated and germ-free hosts. Mean worm lengths were shorter from germ-free than conventional hosts but differences were not statistically significant. These experiments demonstrate that some A. galli larvae may establish themselves and grow for 14 or 21 days postinoculation in a germ-free environment.  相似文献   

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A survey was done in the summer months along the Alaska Highway, in other parts of British Columbia, in northern Alberta, and in the Yukon Territory for steinernematid and heterorhabditid nematodes occurring in the top 10 cm of soil. Steinernema feltiae and Steinernema spp. were found at 18 and Heterorhabditis megidis at 7 sites of 125 sampled. Most nematodes were found where visible insect infestation occurred and where human influence on the habitat was substantial (e.g., agricultural, forested and bush-hedgerow habitats); none was found in grassland or virgin forests. Heterorhabditis megidis occurred in only the southern, warmer, drier region of British Columbia. In the laboratory some steinernematid isolates and H. megidis killed Galleria mellonella larvae at 13 and 22 C, whereas some isolates of Steinernema killed the larvae at only 13 C. Steinernema spp. from three high altitude sites with low, average July temperatures (13-14 C) are cold-active in that they produced infective juveniles at 13 C and killed G. mellonella at 6 C.  相似文献   

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