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1.
This report concerns a collection of parasitic worms from South Africa, and contains a new species of monogenean, Gyrodactylus transvaalensis, six species of adult trematodes, including a new species of Phyllodistomum.P. van der waali, two metacercariae of the Family Clinostomidae and three of the Order Strigeida, as well as two species of cestodes, and larvae of the nematode genus Contracaecum. The adults of previously-known helminths are redescribed, with some remarks on their systematics and biology. Accompanying the material of the new gyrodactylid monogenean there is a specimen which is thought to be a giant of the new form, and this appears to be the first recorded suggestion of the occurrence of gigantism in the Monogenea, and in fact in any kind of helminth. 相似文献
2.
Sharpsnout bream (Diplodus puntazzo) has been used in Adriatic aquaculture for less than a decade, but the decreasing trend of rearing this species will probably
result in its complete substitution by more exploited sea bream (Sparus aurata). Only two facilities still rear both fish species in neighbouring cages in monoculture. A switch of parasites was observed
between sparids during monitoring of the gill monogeneans of farmed fish. In wild fish of the Adriatic Sea, Lamellodiscus elegans (Monogenea: Monopisthocotylea) has previously been reported in annular (Diplodus annularis), and two-banded sea bream (D. vulgaris) and sharpsnout bream (D. puntazzo), and the present study confirmed its presence also in sea bream, in low prevalence and abundance. The exclusively sea bream
monogenean Sparicotyle chrysophrii (Monogenea: Polyopisthocotylea) was also isolated from sharpsnout bream, showing prevalence and abundance values even higher
than in its resident host. In the occurrence of L. elegans in sea bream, the opportunistic switch resulted in lower abundance and prevalence than in the original host, while in the
second case of switching the monogenean S. chrysophrii showed better reproductive capacity on a new host (sharpsnout bream). Both cases point to the possible enlargement of parasite
host range. 相似文献
3.
《African Zoology》2013,48(2):371-377
The parasitic gill monogenean Pseudodactylogyrus anguillae is alien to Africa. In an investigation of 227 longfin eel, Anguilla mossambica, and 26 mottled eel, Anguilla marmorata, sampled from four river systems in the Eastern Cape, South Africa, this parasite was only present on the gills of A. mossambica sampled from the Great Fish River system. In the Great Fish River, it infected 73.2% of the sampled population at a mean intensity of 63.8±34.3 parasites per fish. High prevalence and intensity are indicative of a well-established alien invasive parasitic species. Results showing the absence of P. anguillae from the co-occurring but less abundant A. marmorata indicate that this species may be less susceptible to P. anguillae infection. 相似文献
4.
P. Ie F.N. Mouton 《African Zoology》2013,48(4):319-324
A new species of girdled lizard in the Cordylus genus is described from the south-western Cape, South Africa. Unlike other Cordylus taxa the new form usually has only two supraciliaries per side, the posterior parietals are usually separated mesially by a small post-interparietal scale and the lateral body scales are larger than the dorsal scales. The relationships of this new form to other members of the Cordylus group are discussed. 相似文献
5.
M. B. McCarthy K. S. Townsend P. J. Johnson A. M. LaCarrubba D. L. Voelkl D. H. Volkmann 《Equine Veterinary Education》2021,33(8):e273-e279
A 10-week-old Westphalian filly was presented for vaginal discharge of 14-days' duration. Examination revealed a partial vaginal septum and pyometra. Two Group B streptococcal pathogens (Streptococcus dysgalactiae subspecies equisimilis and Streptococcus equi subspecies zooepidemicus) were isolated from the uterus. Pyometra was successfully treated using endoscopically facilitated removal of intraluminal exudate and locally and systemically administered antimicrobials. The filly was reported to be progressing well at 12 months following treatment with no further evidence of disease. Pyometra has not been previously reported in foals, and vaginal septum is evidently rare in this species. These abnormalities should be considered when young fillies develop purulent vaginal discharge. 相似文献
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7.
Rodents are reservoirs of various types of hantavirus, some of which are agents of hantavirus pulmonary syndrome in humans. Each hantavirus is associated with a single rodent host species but successive spill‐over events may eventually lead to host‐switching and new species’ becoming host of a given pathogen. This study aims to gain an understanding of the spatial ecology of two hantavirus‐host species, Akodon azarae, and Oligoryzomys flavescens, by identifying factors modulating their home range sizes and stability, and by evaluating intra‐ and interspecific spatial aggregation for these species and a third one—Oxymycterus rufus—living in sympatry. For this, eleven capture‐mark‐recapture surveys were carried out, spanning 22 months. We found that A. azarae males have larger and more mobile home ranges than females, independently of the season. Consequently, males could likely have a more relevant role in the transmission of hantavirus because of their greater exposure both to a higher number of contacts between individuals and viral contamination of the environment. Contrasting, O. flavescens individuals showed negligible displacements of their home range through time, which could limit the range of hantavirus spread in host populations. Since O. flavescens is host to Lechiguanas hantavirus (pathogenic to humans) this result encompasses epidemiological relevance, for it may imply the existence of local foci of infection. Additionally, individuals of both species performed excursions outside their home ranges. These events could enable hantavirus spread over distances beyond the normal range of movements and lead to new hantavirus outbreaks in formerly non‐infected rodent populations, favoring the persistence of the virus in nature. 相似文献
8.
Giuseppe Paladini Andrea Gustinelli Maria L. Fioravanti Haakon Hansen Andrew P. Shinn 《Veterinary parasitology》2009,165(3-4):290-297
The monogenean Gyrodactylus salaris Malmberg, 1957 is considered one of the most important parasites of wild salmonids in the European Community due to the heavy ecological and economical damage it has inflicted on Atlantic salmon (Salmo salar) parr populations. Rainbow trout (Oncorhynchus mykiss) is susceptible to G. salaris and can act as a suitable carrier host and, consequently, its trade in EU territory is restricted in relation to the status of “recognized free” zones. Despite the economic importance of rainbow trout farming in Italy, information on the Italian gyrodactylid fauna is lacking and prior to this study, G. salaris had not been officially reported. During a routine health examination of farmed rainbow trout stock throughout Central and Northern Italy in 2004–2005, five fish farms were found to be infected with G. salaris alongside three other gyrodactylids. Morphological and molecular characterisation confirmed the presence of G. salaris, Gyrodactylus teuchis Lautraite, Blanc, Thiery, Daniel et Vigneulle, 1999 and Gyrodactylus derjavinoides Malmberg, Collins, Cunningham et Jalali, 2007, while Gyrodactylus truttae Gläser, 1974 was identified by morphological analysis only. The findings from this study extend the distribution of G. salaris within Europe and highlight the importance of the rainbow trout trade in its dissemination. 相似文献
9.
Michael J. Myers Karyn D. Howard Joseph C. Kawalek 《Journal of veterinary pharmacology and therapeutics》2021,44(1):58-67
This study was initiated to determine whether a comparative pharmacokinetic (PK) approach could be used to expand the pool of approved anthelmintics for minor ruminant species. Accordingly, the PK profiles of six anthelmintics (levamisole, albendazole, fenbendazole, moxidectin, doramectin, and ivermectin) in sheep, goats, and cattle were determined. The PK values determined for each anthelmintic included Tmax, Tlast, Cmax, AUC, AUC/dose, and Cmax/dose. The results of this study demonstrate that a comparative PK approach does not show commonality in the way these six anthelmintics are individually processed by these three ruminants. While some drugs demonstrated identical PK profiles between sheep and goats, none of these drugs demonstrated PK profiles in sheep and goats comparable to the PK profiles found in cattle. The results from this study suggest drug approval across these three ruminants is not a viable concept. However, the resulting PK profiles for each combination of drug and ruminant species represents a new dataset that can be used to support the US FDA Center for Veterinary Medicine's Minor Use/Minor Species indexing process for drug approvals in minor species such as sheep and goats. 相似文献
10.
Herrera E Rivera A Palomares EG Hernández-Castro R Díaz-Aparicio E 《Tropical animal health and production》2011,43(6):1069-1070
The purpose of this study is to determine the etiology of abortions presented in a goat herd declared as free of brucellosis
and vaccinated with RB51 located in Mexico. The serological diagnosis of brucellosis in 33 animals was performed. The study
included three goats that aborted in the last third of gestation and 15 goats that gave birth normally; samples of milk and
vaginal exudate were subjected to bacteriological study. All animals were negative for serological diagnosis, and isolation
of Brucella melitensis was achieved in a single goat from vaginal exudate. However, the particularity is that this goat was negative to the card,
indirect ELISA, and radial immunodiffusion tests. Isolation of a field strain was confirmed by biochemical test resistance
to rifampicin and PCR. It is concluded that a goat which aborted in the last third of gestation was found spreading B. melitensis through vaginal discharge despite being vaccinated with RB51 and seronegative for brucellosis. 相似文献
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12.
D.H.S. Kerimuir 《African Zoology》2013,48(3):194-209
Large-fish population changes in the Sanyati Basin of Lake Kariba between 1960 and 1975 are evaluated and discussed. The early lake population following closure of the dam wall in 1958 was similar to the pre-impoundment riverine population with Labeo spp., Distichodus spp., Clarias gariepinus and two characid species dominating gill-net catches. Exceptions were mormyrids, scarce in the new lake although abundant in the river, and Oreochromis mortimeri, scarce in the river but expanding rapidly in the lake. Productivity in the new lake in terms of ichthyomass relative to later years was high. In later years following closure several of the early abundant mostly potamodromous species declined rapidly (C. gariepinus, Labeo spp., Distichodus spp.,) and by 1975 they were unimportant. Mormyrids, cichlids and two silurid species increased significantly in catches as did the characin, Hydrocynus vittatus; the latter as a result of the expansion of the freshwater sardine population, from 1970. While early populations were essentially herbivorous later populations were largely insectivorous/molluscivorous. Concomitant with these changes new species appeared, while a few disappeared. Possible sources of origin of the new arrivals are discussed. Salient features of the entire evolutionary process are summarized, while some of the lessons leamt from Kariba, and a few recommendations arising from this, are listed in the conclusion. 相似文献
13.
H. Kunz 《African Zoology》2013,48(3):186-189
A new species of the genus Parategastes Sars, 1904 (Copepoda, Harpacticoida) was found during an ecological study of zooplankton in Langvlei, one of the Wilderness Lakes near George on the southern Cape coast. The species, Parategastes coetzeel, is described and a key is given for the identification of the various species of Parategastes. 相似文献
14.
Sessile peritrichs (Ciliophora: Peritricha) were collected from freshwater fish in lakes, rivers, streams and fish-ponds in the Transvaal, South Africa Nine species of the genus Apiosoma Blanchard, 1885 are described, i.e. seven new species; A. caulata sp.n., A. curvinucleata sp.n, A. micralesti sp.n., A. mothlapitsis sp.n., A. obliqua sp.n., A. phiala sp.n. and A. viridis sp.n., and two known species; A. nasal is (Timofeev, 1962) and A. piscícola Blanchard, 1885. One new species of the genus Ambiphrya Baabe, 1952 is described, i.e. A. neobolae sp.n. A new sgenus, Scopulata gen.n. is proposed for species with a broad scopula and compact macronucleus. Two previously described Scyphidia species are incorporated in this genus, i.e. S. dermata (Viljoen & Van As, 1983) comb.n. and S. epibranchialis (Viljoen & Van As, 1983) comb.n., as well as a new species, S. constricta sp.n. Compendiums of all the known fish-associated species of these genera are provided. 相似文献
15.
The spatial genetic structure of a species, and whether distinct genetic lineages are present, is strongly influenced by their biology and habitat requirements. Given habitat specificity and low vagility, many herpetofaunal species are reservoirs for high levels of cryptic diversity; chameleons are a case in hand. The common flap-necked chameleon Chamaeleo dilepis has a large range that spans much of sub-Saharan Africa. Within South Africa, the species is largely confined to the north-eastern and central areas of the country, and occurs from the coastal forests in southern KwaZulu-Natal westwards into Namibia. Their large range, together with anecdotal evidence that there is considerable morphological and phenotypic diversity across the range, suggests a questionable taxonomy with possible cryptic lineages. The aims of the present study were to investigate whether C. dilepis is genetically structured across parts of its South African range, and whether this species (as it currently stands) might include cryptic lineages. To this end, 72 C. dilepis individuals sampled from four localities across South Africa (Gauteng, n = 2; KwaZulu-Natal, n = 2) were sequenced for two mitochondrial markers (ND4 and 16S). The phylogenetic results suggest that C. dilepis is indeed spatially structured. In addition, the large sequence divergence values between groups strongly suggests the presence of cryptic lineages and, pending the inclusion of more data from a larger geographic range, the group may be in need of a taxonomic revision. 相似文献
16.
Unrecognized diversity in New Guinean crayfish species (Decapoda,Parastacidae): The evidence from molecular data 
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下载免费PDF全文 The phylogenetic relationships among imported ornamental crayfish belonging to the genus Cherax were inferred from a combined dataset of 3 mitochondrial genes (COI, 16S and 12S) and by comparison with available GenBank sequences of 14 Cherax species. Furthermore, the concordance of previously described species obtained from a wholesaler (Cherax boesemani, C. holthuisi and C. peknyi) with available GenBank sequences was verified based on COI with special respect to comparison with sequences assigned as Cherax species. Recently described species C. gherardiae, C. pulcher and C. subterigneus belong to the northern group of Cherax species. Comparison and analysis with other GenBank COI sequences show previously unreported diversity of New Guinean species, suggesting 5 putative new species. Surprisingly, species assigned to the subgenus Astaconephrops do not form a monophyletic clade; this subgenus should be reappraised relative to the purported typical morphological characteristic of the uncalcified patch on male chelae. Increasing importation of crayfish underscores the importance of accurate species identification. Use of basic molecular methods is a necessary requisite for documenting occurrence, abundance and population trends of target species. Consequently, it helps to support eventual conservation decision‐making by stakeholders. 相似文献
17.
Martin BLÁHA Jiří PATOKA Bella JAPOSHVILI Marek LET Miloš BUŘIČ Antonín KOUBA Levan MUMLADZE 《Integrative zoology》2021,16(3):368-378
The phylogeny of European crayfish fauna, especially with respect to Eastern European species, is still far from being completely resolved. To fill this gap, we analyzed most of the European crayfish species focusing on the phylogenetic position of the endemic crayfish Astacus colchicus, inhabiting Georgia. Three mitochondrial and one nuclear marker were used to study evolutionary relationships among European crayfish species, resulting in the unique phylogenetic position of A. colchicus indicating independent species status to A. astacus. Phylogenetic analyses revealed a deep molecular divergence of A. colchicus in comparison to A. astacus (6.5–10.9% in mtDNA and 1.1% in nDNA) as well as to Pontastacus leptodactylus and P. pachypus (5.5–10.0% in mtDNA and 1.4–2.4% in nDNA). Absent ventral process on second male pleopod and abdominal somites II and III with pleura rounded lacking prominent spines clearly indicate taxonomic assignment to the genus Astacus; however, the species is distributed almost in the middle of Ponto-Caspian area typical by occurrence of the genus Pontastacus. Several morphological indices linked to head length, carapace, and total body length and width were found to demonstrate apparent differences between A. colchicus and A. astacus. Although this study provides a novel insight into European crayfish phylogeography, we also point out the gaps in comprehensive study of the P. leptodactylus species complex, which could reveal details about the potential species status of particular species and subspecies within this genus. 相似文献
18.
Prenatal development in greater mouse‐eared bat,Myotis myotis (Borkhausen, 1797) (Chiroptera, Vespertilionidae) 下载免费PDF全文
下载免费PDF全文 Order Chiroptera is the second largest mammal group after rodents. An understanding of the development of the bats, which is a very special mammal group in terms of their lifestyles, morphology and their ability to fly, is very important because most of the adult anatomical differences characterizing species occur during organogenesis. In this study, developmental stages were determined for Myotis myotis species based on external morphological characteristics from embryos obtained from wild‐caught pregnant females. The developmental stages of M. myotis were comparable with those of other bat species. 相似文献
19.
V.B. Whitehead 《African Zoology》2013,48(2):87-90
Fideliids are ground-nesting bees, covered in a dense pale straw to brown pile, with pollen being carried on an abdominal scopa. Fidelia paradoxa, F. villosa and F. kobrowi are restricted to flowers of the Mesembryanthemaceae, and Parafidella major and two new Parafidelia species to Grielum and Neuradopsls (Roseaceae). Parafidelia ornata collects pollen mainly from Tribulus and Tribulocarpus and P. pallidula only from Sisyndite (Zygophyllaceae). Parafidelia friesei visits flowers of Sesamum (Pedaliaceae) and Fidelia braunsiana is confined to Berkheya (Asteraceae). The rainfall pattern divides the species into early summer bees (7 species) of the winter rainfall and autumn bees (4 species) of the summer rainfall areas. Two of the above species have populations in both regions. The winter rainfall bees have a south-western distribution with Graaff-Reinet the eastern limit but the summer rainfall species occur further north, with the eastern Botswana border their eastern limit and Keimoes on the Orange River their southern limit. 相似文献
20.
A.S. Thandar 《African Zoology》2013,48(4):290-304
The sclerodactylid subfamily Sclerodactylinae is restricted to include only those forms with a short, compact, tubular calcareous ring and a new subfamily Sclerothyoninae is diagnosed to accommodate two new southern African monotypic genera Sclerothyone and Temparena, with compact but non-tubular calcareous rings. The new genera are erected respectively for Ludwig and Heding's (1935) Cucumaria? velligera and C.l chuni, formerly classified in Pentamera. This brings the total number of sclerodactylid holothurians known from southern Africa to six genera and seven species. All taxa are diagnosed and/or described, a key is provided for all southern African species and their local distributions are mapped. 相似文献