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Fish associations with different types of littoral habitats were studied in four canyon‐shaped reservoirs in the Czech Republic in years 2010 and 2011 by gillnets. Two to three habitats per reservoir–beaches (former meadows), stump fields (former forest) and rubble slopes–were defined and sampled along the longitudinal axis of reservoirs. Effects of reservoir, habitat and locality (position along longitudinal axis) on fish biomass, abundance and species structure were tested for juvenile and adult fish separately. Hierarchical analysis of variance revealed that habitats differed significantly in fish biomass and abundance. Redundancy analysis showed that analysed environmental variables had significant influence on fish community structure. Most variability in community structure was explained by reservoir and then by combination of habitat and slope steepness. Locality position had the smallest influence on community structure. For both adult and juvenile fish total abundance and biomass, the most inhabited habitat was beaches; rubble slopes were the least inhabited. Habitat associations differed among species. Among adults, bream Abramis brama, white bream Blicca bjoerkna and roach Rutilus rutilus were associated with beaches and stump fields, whereas perch Perca fluviatilis, ruffe Gymnocephalus cernuus, asp Aspius aspius and pike Esox lucius were associated with rubble slopes. Bream, white bream, bleak Alburnus alburnus, roach, ruffe and pikeperch Sander lucioperca were associated with beaches among juveniles, whereas the only juvenile associated with rubble slopes was perch. We showed that most common species are associated with distinct habitats and also that utilisation of various littoral habitats differs in general.  相似文献   
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Plant Foods for Human Nutrition - The purpose of this study was to compare the yield, chemical composition, antimicrobial and antioxidant properties of essential oils isolated from leaves of Laurus...  相似文献   
4.
Hygiene and sanitation play a major role in any effective disease control programme for poultry production and processing premises. Various deficiencies in disinfection may induce that chains of infections are not broken from one stock to another. The present study investigated the efficacy of disinfection on a broiler farm and in a plant processing poultry from the investigated farm. Besides inspection of disinfection, the influence of contamination on broiler carcasses and consequences of this contamination on sanitation of the processing lines were studied. Swabs from surfaces coming into contact with the handled raw material were taken and evaluated. The results obtained by a standard microbiological swab method were evaluated and compared with an ATP-bioluminescence method. The investigations included determination of total counts of microorganisms, coliform bacteria and moulds. When employing the standard plate-count method, the total counts of microorganisms (TCM) reached <1, 1-100 and >100 CFU in 0, 12 and 88% swabs on poultry farm and in 22%, 36% and 42% swabs in the processing plant, respectively. The bioluminescence method was used only in the processing plant and contamination corresponding to <100, 100-300 and >300 relative light units (RLU) was detected in 80%, 10% and 10% swabs respectively.  相似文献   
5.
Four laboratory-hatched European kestrels Falco tinnunculus L. were fed on laboratory mice and common voles Microtus arvalis Pallas previously inoculated with different doses of sporulated oocysts of Caryospora kutzeri B?er, 1982. Two kestrels that were fed infected mice shed C. kurtzeri oocysts 6 days after ingesting murine tissues. To compare direct and indirect transmissions, two of the kestrels were subsequently directly inoculated with 10(5) sporulated C. kutzeri oocysts and became patent on days 8 and 9 and shed caryosporan oocysts up to day 25 post inoculation. Additionally, four mice were inoculated with 10(6) oocysts in order to examine mouse tissues for the presence of developmental stages of C. kutzeri. No coccidian stages were found in the tissues of inoculated mice. The experiment showed that developmental stages of C. kutzeri are able to survive in mouse tissues and cause infection of suitable host after their ingestion.  相似文献   
6.
Parasitological examination of two ornate Nile monitors Varanus ornatus (Daudin, 1803) imported from Benin revealed the presence of a new species of Caryospora. Oocysts of Caryospora varaniornati sp. n. are spherical to slightly subspherical, 12.0 (11-12.5) x 11.5 (11-12) microm, without amicropyle and oocyst residuum, and occasionally possessing one small polar granule. Sporocysts are broadly ellipsoidal, 8.8 (8.5-9.5) x 6.7 (6.5-7) microm; a lentil-like Stieda body is present, ca. 0.5 x 1 microm; substieda body not visible. Experimental infection of a closely related host, Varanus niloticus (L.), did not lead to the oocyst excretion despite the fact that one of the experimentally inoculated monitors was immunosuppressed by dexamethasone. Histological examination did not reveal stages of coccidian development. Therefore, it is possible that C. varaniornati is strictly host specific.  相似文献   
7.
A serological survey for bovine viral diarrhoea virus (BVDV) antibodies on a collection of 1295 serum samples obtained from 6-12 months old cattle originating from 45 farms in Slovakia was carried out. On 13 farms more than 90% of the examined animals were seropositive, on 14 farms 71-90% seroprevalence was observed, on 13 farms only 50-70% animals were found to be positive for BVDV antibodies, while the remaining 5 farms showed fewer than 50% seropositive animals. The average incidence of BVDV antibodies (around 70%) was similar as determined 30 years ago. Of 84 serum samples from seronegative animals originating from 14 farms in which 70-98% seropositivity was observed, six were positive in Ag-BVDV ELISA indicating persistently infected (PI) cattle. On a farm to which animals were imported from abroad, a BVD outbreak was observed. Of 110 animals tested, four were positive in Ag-ELISA indicating the presence of PI cattle on this farm. Genetic typing of two isolates from imported animals performed by RT-PCR (324/326 primers from 5'-UTR), sequencing of PCR products and computer-assisted phylogenetic analysis revealed that they belong to BVDV-1 h group.  相似文献   
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Saliva-activated transmission of Borrelia afzelii Canica, Nato, du Merle, Mazie, Baranton et Postic, 1993 was demonstrated using salivary gland extract (SGE) from Ixodes ricinus (L., 1758) ticks and C3H mice. Injection of Borrelia spirochaetes together with SGE increased the level of bacteraemia and accelerated the appearance of bacteria in the urinary bladder, compared with the injection of spirochaetes alone. More I. ricinus nymphs became infected when feeding on mice inoculated with B. afzelii plus SGE. Analysis of cytokines produced by cells of draining lymph nodes from SGE-treated mice showed a suppression of proinflammatory cytokines IFN-gamma, IL-6 and GM-CSF following a transient upregulation in comparison with the control mice infected without SGE.  相似文献   
10.
"Kennel cough" in dogs in animal shelters is readily transmissible, reduces adoption rates, and commonly leads to the euthanasia of affected dogs. In cats, tracheobronchitis, conjunctivitis, and pneumonia have been associated with Bordetella bronchiseptica infection-but most cases of upper-respiratory infection (URI) probably are caused by herpesvirus and calicivirus, and many B. bronchiseptica culture-positive cats are clinically normal. Our prospective observational study was undertaken to document the contribution of B. bronchiseptica to disease in cats and dogs from two animal shelters undergoing outbreaks of canine kennel cough, to evaluate whether cross-species transmission might have occurred, and to determine if the presence of infected cats represented a risk to dogs. Clinically defined cases of kennel cough in dogs and URI in cats were investigated in two shelters by calculating clinical-disease incidence, alveolar-lavage cytological examination, bacterial and viral cultures, antibiotic-susceptibility testing, and molecular fingerprinting by pulsed-field gel electrophoresis.In a 40-cat and 40-dog "no-kill" shelter, the prevalences of culture positivity were 47% for B. bronchiseptica and 36% for calicivirus at the same time as two resident dogs demonstrated clinical cough. When no dogs had kennel cough 3 months later, 10% of cats were B. bronchiseptica-culture-positive and 63% calicivirus positive. In a large traditional shelter, the incidence of kennel cough in dogs increased over 12 weeks to a maximum of 19 cases/week/120 dogs, during which time the culture prevalence was 23% for B. bronchiseptica in dogs and 47% in cats. Three to 6 months before the kennel-cough epidemic, no dogs or cats were B. bronchiseptica positive. Very little genetic variability was detected in isolates from these shelters; all isolates except one corresponded to a single strain type which was identical to the pattern in a vaccine used in these shelters. Isolates from other cats, a horse, a llama, and a sea otter were genetically distinct from the shelter isolates. There was widespread resistance to cephalosporins and ampicillin, but low or no resistance to amoxicillin/clavulanate, trimethoprim-sulfamethoxazole, tetracycline, and enrofloxacin. Greater percent resistance was observed in the traditional shelter than in the no-kill shelter and feline isolates were more likely to be resistant than canine isolates.  相似文献   
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