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1.
Abstract

Infections of Myxobolus corneus (species nova) are described from the eyes of bluegills Lepomis macrochirus from Mt. Olive, Illinois. Individual eyes had up to 36 trophozoites (0.250.8 mm in diameter) distributed peripherally around the corneal margin with few beyond the level of the inner edge of the iris. Mature spores were oval in front view and measured 8.0–10.5 um long and 6.5–9.0 μm wide. Spores of M. corneus resembled most closely those of Myxobolus cartilaginis (Hoffman, Putz, and Dunbar, 1965). Statistical comparison of spores of the two species with similarly prepared paratype material revealed that M. corneus has significantly smaller polar capsules than does M. cartilaginis. Myxobolus corneus is the fourth species of Myxobolus to be reported from bluegills in North America.  相似文献   

2.
Abstract

The ranavirus, epizootic hematopoietic necrosis virus (EHNV), is endemic to southern Australia with natural outbreaks resulting in mass mortality events in wild Redfin Perch Perca fluviatilis (also known as Eurasian Perch) and less severe disease in farmed Rainbow Trout Oncorhynchus mykiss. To further investigate the host range for EHNV, 12 ecologically or economically important freshwater fish species from southeastern Australia were exposed experimentally to the virus. A bath-challenge model at 18 ± 3°C was employed with limited use of intraperitoneal inoculation to determine if a species was likely to be susceptible to EHNV. Of the species tested, Murray–Darling Rainbowfish Melanotaenia fluviatilis and Dewfish Tandanus tandanus (also known as Freshwater Catfish) were considered to be potentially susceptible species. EHNV was isolated from approximately 7% of surviving Eastern Mosquitofish Gambusia holbrooki, indicating this widespread alien fish species is a potential carrier. The infection of Silver Perch Bidyanus bidyanus and Macquarie Perch Macquaria australasica and the lack of infection in Murray Cod Maccullochella peelii peelii and Golden Perch Macquaria ambigua ambigua after exposure to EHNV via water confirmed earlier data from Langdon (1989). Five other species of native fish were potentially not susceptible to the virus or the fish were able to recover during the standard 35-d postchallenge observation period. Overall, it appeared that EHNV was less virulent in the present experimental model than in previous studies, but the reasons for this were not identified.

Received May 21, 2012; accepted November 1, 2012  相似文献   

3.
Abstract

Pseudorhabdosynochus kritskyi n. sp. from gag Mycteroperca microlepis (Perciformes: Serranidae) of the Gulf of Mexico is described and differs from all known species of the genus by the shape of the vagina. It may be further differentiated from P. americanum, P. amplidiscatum, P. caballeroi, P. epinepheli, P. latesi, P. monaensis, and Cycloplectanum magnisquamodiscum in having fewer rows of scales in each squamodisc. This new species is most similar to P. beverleyburtonae, P. bocquetae, P. cupatum, P. lantauensis, P. melanesiensis, P. querni, P. serrani, P. summanae, P. vagampullum, and Cycloplectanum riouxi in having 15 or fewer squamodisc rows, but it may be separated by differences in either squamodisc morphology or differently shaped hamuli or bars.  相似文献   

4.
《African Zoology》2013,48(2):340-341
A junior homonym was detected among fossil echinoid genera and the following replacement name is proposed: Ekerekeia nom. nov. for Farquharsonia Currie, 1927 (nec Collin, 1922). Accordingly, new combinations are herein proposed for the species currently included in this genus: Ekerekeia crenulata (Kier 1972) comb. nov. from Farquharsonia crenulata Kier, 1972 and Ekerekeia somaliensis (Currie, 1927) comb. nov. from Farquharsonia somaliensis Currie, 1927.  相似文献   

5.
Summary

In this communication the test procedure is described for an indirect enzyme‐linked immunosorbent assay (ELISA) for the detection of antibodies against bovine leukosis virus (BLV). Test sera are incubated in polystyrene microtiter plates sensitized with a partly‐purified preparation of BLV. Bovine antibodies are detected with anti‐species immunoglobulin conjugated to the enzyme horseradish peroxidase, followed by the addition of the enzyme substrate.  相似文献   

6.
Abstract

Morphological studies were carried out on adult postmetamorphic females of three native South American genera of Lernaeidae (Crustacea: Copepoda: Cyclopoida) and these were compared with the imported species Lernaea cyprinacea. Two of the native species represent new genera, which are described as Amazolernaea sannerae gen. et sp. nov. and Bedsylernaea collaris gen. et sp. nov. The third native species had already been described as Perulernaea gamitanae Thatcher and Paredes, 1985. Amazolernaea sannerae from the cichlids Cichla monoculus and speckled pavon C. temensis was characterized as having four similar petal-like anchors, a long slender neck, thoracopods 1 and 2 close together, and a genital pore located equatorially in the well-developed hindbody. Bedsylernaea collaris differs from all known lernaeids in having a large inflated head region with one bulbous anchor on either side, a slender neck, a stout hindbody with a large pregenital prominence, a genital pore that is anterior to the midpoint on the hindbody, and collar-like extensions on the anterior extremity of the hindbody. Perulernaea gamitanae has two large and two small unbranched anchors, a long neck with prominent glands, and an elongate hindbody with a genital pore that is posterior to the midpoint. In contrast, all valid species of Lernaea have four frequently branching anchors, a neck region and hindbody that are not well defined, a short abdomen, and a genital pore at or near the posterior extremity.  相似文献   

7.
Abstract

Observations were made on the feeding and host selection behavior of the aegid isopod Rocinela angustata. Host susceptibility was assessed by placing isopods into laboratory tanks containing 14 common species of Alaska marine fishes. Five species of Sebastes and Blepsias bilobus were attacked within a few minutes of the introduction. Five species—Enophrys bison, Eumicrotremus orbis, Hexagrammos lagocephalus, Pleuronectes asper, and Pholis laeta—were attacked 10–24 h after introduction of the isopods. Three species—Podothecus acipenserinus, Liparis gibbus, and Lycodes brevipes—were not successfully attacked, even when held in isolation with an isopod for 14 d. Starved isopods isolated with B. bilobus attached to fish within 1 h and remained attached 4–14 d. The isopods reattached 1–4 d after detachment. Isopod digestive tracts cleared within 24 h after detachment.  相似文献   

8.
Background: Natural autoantibodies (N(a)ab) were found in every species tested so far, and are likely important in maintaining homeostasis.

Objectives: (1) To determine N(a)ab in Bos taurus calves, (2) evaluate effects of diet and age on N(a)ab binding repertoires in calves, and (3) delineate bovine liver cell lysate (BLL) antigens related with variation in rumen score and body weight.

Animals and methods: Effects of age and diet on staining of BLL fragments by IgM and IgG antibodies in serum samples collected at 20 or at 26 weeks of age from bull calves either fed a restricted or ad libitum diet were analyzed using quantitative Western blotting. Correlations between fragments stained and grouping of calves were done by Principal Component Analysis (PCA). Redundancy analysis (RDA) was done to relate rumen score and body weight variation at slaughter at 27 weeks of age with stained BLL fragments.

Results: In sera from all calves IgM and IgG antibodies binding BLL antigens were found. Corresponding fragments were stained, but quantitative differences in staining intensities were related to diet and age for both IgM and IgG. PCA revealed that age had a greater influence than diet on BLL fragment staining. RDA suggested that staining by IgM or IgG of specific BLL fragments was related with variation in rumen score and body weight.

Conclusions and clinical importance: Analyses of N(a)ab in serum could be a potential tool to estimate the health status of cattle, and be used to evaluate effects of husbandry practices.  相似文献   

9.
Abstract

Very heavy infections of Trichodina spheroidesi apparently killed wild specimens of orange filefish Aluterus schoepfi and whitespotted filefish Cantherhines macrocerus in Puerto Rico. Possibly it is a primary pathogen under some conditions. The hyperparasite Endosphaera engelmanni occurred in this protozoan, and thus the range of both parasites was extended from the temperate zone to the tropics. Sand drums Umbrina coroides, collected off Humacao, Puerto Rico, had heavy infections of Cryptocaryon irritans, which has seldom been shown to injure wild fishes. We have not seen other examples of these diseases in more than 3,000 specimens of 270 species of wild marine fishes examined in Puerto Rico, although Cryptocaryon irritans is common in local marine aquarium fishes. Sharpnose puffers Canthigaster rostrata often cause outbreaks of Cryptocaryon irritans when placed in marine aquaria.  相似文献   

10.
Summary

A large Babesia species occurs in sheep on the North Sea islands of the Netherlands. The tick Haemaphysalis punctata is a vector. Its pathogenicity appears to be low. It is morphologically similar to a Turkish strain, considered to be B. motasi, which is also transmitted by Haemaphysalis ticks. It differs from the Turkish parasite serologically as well as in cross‐immunity tests and in not being effective to goats.

There may be a group of morphologically similar parasites with serological differences and different infectivity for sheep and goats. As it is impossible to know which one is to be considered as the original B. motasi, we designate the Dutch parasite as B. motasi (Netherlands). Anaplasma mesaeterum was found to occur on the island of Texel as well as on Ameland, where it had been found initially.  相似文献   

11.
Summary

Data are presented on the incidence of various streptococcal infections in pigs in the Netherlands. 314 Strains isolated in the course of routine post‐mortem diagnosis were examined. The most frequently occurring streptococcus was S. subacidus (bio) type II which was isolated in 31.2% of the cases.

S. suis type 2 (Serogroup R) and S. equisimilis (Serogroup C) constituted 16.2% and 13.7% of the isolates respectively. Besides meningitis, endocarditis and polyserositis S. suis type 2 infections may frequently be associated with pneumonia (42%).

The biochemical profiles of the various S. suis and S. subacidus (bio) types are presented. The profile of both species is almost identical. It seems justified to use the name S. suis for strains with this characteristic profile and to abandon the name S. subacidus. Haemolysis does not appear to be a suitable characteristic to screen for S. subacidus/S.suis types. In comparing three serological methods for typing S. suis type 2, gel precipitation using Fuller's extract and slide agglutination give an almost 100% correlation. These two methods are recommended for serotyping.  相似文献   

12.
Summary

The influence of temperature (10° C and 20° C) on pharmacokinetics and metabolism of sulphadimidine (SDM) in carp and trout was studied.

At 20° C a significantly lower level of distribution (Vdarea ) and a significantly shorter elimination half‐life (T (½>) β) was achieved in both species compared to the 10° C level. In carp the body clearance parameter (ClB (SDM) was significantly higher at 20° C compared to the value at 10° C, whereas for trout this parameter was in the same order of magnitude for both temperatures.

N4‐acetylsulphadimidine (N4‐SDM) was the main metabolite of SDM in both species at the two temperature levels. The relative N4‐SDM plasma percentage in carp was significantly higher at 20° C than at 10° C, whereas there was in trout no significant difference.

In neither species was the peak plasma concentration of N4‐SDM (CmaxN4‐SDM)) significantly different at two temperatures.

The corresponding peak time of this metabolite (Tmax (N4‐SDM)) was significantly shorter at 20° C compared to 10° C in both carp and trout.

In carp at both temperatures, acetylation occurs to a greater extent than hydroxylation. Only the 6‐hydroxymethyl‐metabolite (SCH2OH) was detected in carp, at a significant different level at the two temperatures. Concentrations of hydroxy metabolites in trout were at the detection level of the HPLC‐method (0.02‐μg/ml). The glucuronide metabolite (SOH‐gluc.) was not detected in either species at the two temperatures.  相似文献   

13.
Abstract

AIMS: To obtain information and compare the prevalence of Chlamydiaceae in riverine buffalo (Bubalus bubalis) and cows (Bos taurus) in Egypt with and without clinical signs of reproductive disease.

METHODS: Vaginal swabs and blood samples were collected from animals attending Governmental Veterinary Clinics without (buffalo n=39, cows n=20) and with (buffalo n=63, cows n=53) signs of reproductive disease. Serum samples were tested for antibodies to Chlamydiaceae using complement fixation testing (CFT). Vaginal swabs were tested for Chlamydiaceae following inoculation into Vero cells and 6-day-old embryonated chicken eggs, using modified Giménez and immunoperoxidase staining, PCR analyses targeting the omp2 gene, and Restriction Fragment Length Polymorphism PCR (RFLP-PCR) for species identification.

RESULTS: Antibodies to Chlamydiaceae were detected in 30/39 (77%) and 50/63 (79%) buffalo without and with signs of reproductive disease, respectively, and 10/20 (50%) and 39/53 (74%) of cows with and without signs of reproductive disease, respectively. Positive samples from PCR analysis were identified in 31/39 (79%) and 37/63 (59%) buffalo without and with signs of reproductive disease, respectively, and 12/20 (60%) and 46/53 (89%) of cows without and with signs of reproductive disease, respectively. Using RFLP-PCR, 57/68 (84%) of samples from buffalo, and 47/58 (81%) from cows, were identified as Chlamydophila psittaci and the reminder as Cp. abortus. From the CFT and PCR results there was no significant difference in the prevalence of positive samples between species, or between animals without or with signs of reproductive disease.

CONCLUSION: The presence of anti-Chlamydiaceae antibodies in 77% of the animals with signs of reproductive disease and the detection of Chlamydiaceae in 72% of vaginal swabs of the animals suggest a pathogenic role by Chlamydiaceae in riverine buffalo and cows. The main Chlamydiaceae found in the genital tract of cattle in Egypt were Cp. psittaci and Cp. abortus.

CLINICAL RELEVANCE: Chlamydophila spp. should be included in diagnostic algorithms for reproductive disorders, in order to assess the real burden of Chlamydophila associated disease in buffalo and cattle and to evaluate the potential value of vaccines.  相似文献   

14.
Background: Both Bovine herpesvirus (BoHV-1) and Bubaline herpesvirus (BuHV-1) have been reported to cross the species barrier. Antibody seroconversion in glycoprotein E (gE) blocking ELISA during BuHV-1 infection has been documented. Recent diagnostic efforts have focused on the development and application of discriminatory tests to distinguish between infections with BoHV-1 and BuHV-1.

Objective: To evaluate the impact and distribution of these two infections in water buffalo farms in two regions (Piedmont (n = 3) and Campania (n = 10), Italy) where infectious bovine rhinotracheitis control programs have been implemented.

Animals and methods: Sampling was carried out on 13 buffalo farms comprising 1089 animals using specific gE-indirect ELISA's test able to discriminate among BoHV-1 and BuHV-1 infections.

Results: 59.0% of animals reacted positive to ELISA (irrespective of whether BoHV-1 or BuHV-1 antigen was used) and 86.4% of these were reactive to BuHV-1 only, whereas 11.8% showed absorbance values for both antigens and were classified as inconclusive. There was a statistically significant age-related difference in BuHV-1 infection rates but not in overall individual (47% vs. 58%) or herd prevalence (100% vs. 90%) of infection between the two regions.

Conclusion: The low percentage of sera reactive to BoHV-1 (1.8%, 12/643) indicates that BuHV-1 may be the main circulating alphaherpesvirus infection in Mediterranean water buffalo in the two study areas. Since Bubalus bubalis is included in Directive 64/432/EEC on animal health problems affecting intra-community trade in bovine animals, diagnostic testing with nonspecific ELISA for BoHV-1 infection in buffalo may yield false-positive reactions. This scenario could lead to economic losses and hamper buffalo trade and movement, particularly for reproduction purposes.  相似文献   


15.
Abstract

Aphanomyces piscicida is an important pathogen that plays a role in the morbidity and mortality of various fish species around the world. The poor quality of current identification techniques for this fungus led to the development of highly sensitive and specific polymerase chain reaction (PCR) techniques. Primers derived from the ITS1 and ITS2 regions of A. piscicida NJM 0204 were designed for the detection and identification of fish-pathogenic A. piscicida, with the potential for the diagnosis of mycotic granulomatosis (MG). Polymerase chain reaction amplification showed that the primer set was specific only to fish-pathogenic A. piscicida, not to non-fish-pathogenic Aphanomyces, Saprolegnia spp., Achlya spp., Dictyuchus spp., and Lagenidium spp. In addition, PCR revealed an improved sensitivity sufficient to detect A. piscicida in artificially infected goldfish Carassius auratus. Results demonstrated that the PCR method established in this study is effective for the detection and identification of A. piscicida with MG.  相似文献   

16.
Abstract

Serological detection of bacterial pathogens in fish tissue is an important tool for surveying epidemiological situations. Whenever antibacterial treatment of fish is recommended, it becomes necessary, however, to culture the pathogen for sensitivity testing. An enzyme-linked immunosorbent assay (ELISA) was developed to identify Aeromonas salmonicida in culture. This serological identification can partly substitute for biochemical characterization of the organism and thus decrease the time between isolation and sensitivity testing by at least 3 d. The ELISA works with only one bacterial colony and yields results within 4 h. During this time, a bacterial suspension can be prepared for the resistance test. The specificity of an antiserum, raised in rabbits, against whole cells of A. salmonicida can be increased by adsorption with strains of cross-reacting species. However, difficulties arise when serologically heterogeneous species (e.g., A. hydrophila) are used as the cross-reacting bacterium. In the present study, severalfold adsorption with four isolates did not totally rule out cross-reactivity against additional strains. Therefore, the strain in question should also be checked for colony morphology, production of pigment, or presence of cytochrome oxidase to validate the serologically obtained result.  相似文献   

17.
Thirteen nematode species are recorded from Botswana. Illustrations are given for Ecuménicas monohystera (de Man, 1880) Thome, 1974; Eudorylaimus diadematus (Cobb in Thorne & Swanger, 1936) Andrássy, 1959; Labronema mauritiense Williams, 1959; Disoolaimus brevis Siddiqi, 1964; D. major Thorne, 1939; Aporcelaimellus adriaani Botha & Heyns, 1990; A. micropunctatus Botha & Heyns, 1990; A. papillatus (Bastian, 1965) Baqri & Khera, 1975; A. parapapillatus Botha & Heyns, 1990 and a specimen belonging to Prodorylaimus or to Laimydorus. Measurements are given for the above-mentioned species as well as for Discolaimium simplex Siddiqi, 1965 and Discolaimoides bulbiferus (Cobb, 1906) Heyns, 1963. A new Mesodorylaimus species viz. M. usitatoides is described. For the first time males are described for A. adriaani and A. micropunctatus. Discolaimus paramajorCoomans, 1966 is considered a possible synonym of D. major.  相似文献   

18.
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19.
Abstract

The nearly complete small subunit 16S ribosomal RNA (rRNA) gene sequence amplified by polymerase chain reaction was determined for Flavobacterium psychrophilum (formerly Flexibacter psychrophilus) by using automated nucleotide sequencing. The sequence was found to be 1,465 base pairs (bp) in length, a size consistent with previously determined sequences for 14 other bacterial species from various taxa, including the yellow-pigmented bacteria. Sequence signatures confirmed that this organism was a member of the bacterial division Bacteroides–Flavobacterium. Parsimonious and additive phylogenetic trees were constructed with homology, and pairwise evolutionary distances were used to estimate phylogenetic relationships. Data show that F. psychrophilum, F. columnare, and Flexibacter maritimus are closely related, have a common descent, and represent a distinct group within the division Bacteroides–Flavobacterium. This group also included other organisms from the genera Flavobacterium and Cytophaga. Further, Flavobacterium aquatile, the type species for the genus Flavobacterium, was also determined to be a member of this “Flavobacterium–Cytophaga–Flexibacter subcomplex.” This supports previous assertions that the type strain of Flavobacterium should be changed to a more representative species such as Flavobacterium breve.  相似文献   

20.
Certain aquatic Oligochaeta live successfully in organic-polluted waters while others cannot tolerate such conditions. Tubifex tempUtoni Southern and Llmnodrttus hoffmeisteri (Clap.), two non-gilled species, are compared to Branchiura sowerbyi (Beddard) and Dero nivea (Aiyer), two gilled species, concerning their haemoglobin concentration, the influence of low oxygen availability on the respiration rate and their reactions in an oxygen gradient. In contrast with L. hoffmeisteri and T. templetoni where a very narrow range of respiration dependency (pO2, 0-12 mm Hg) is found, B. sowerbyi and D. nivea have a level of respiratory dependence from pO2, 0-131 mm Hg. Haemoglobin concentrations are 6,238 - and 6,452 g/100 cm2 blood in L. hoffmeisteri and T. templetoni and 3,011 and 1,611 g/100 cm2 in B. sowerbyi and D. nivea respectively. In the oxygen gradient all four species have a preference for water with a high oxygen content.  相似文献   

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