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1.
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   
2.
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   
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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   
5.
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   
6.
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   
7.
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   
8.
Expression of L-selectin was determined by single- and two-colour immunofluorescence on granulocytes, peripheral blood mononuclear cells (PBMC) and blasts of bovine origin by means of a monoclonal antibody IVA94 which recognizes bovine L-selectin (CD62L). Cells were separated from peripheral blood of healthy cattle and colleagues infected with bovine leukaemia virus (BLV). BLV-infected animals comprised lymphocytotic and non-lymphocytotic cows. L-selectin was expressed on 90-98% of granulocytes in all tested animals. The percentage of PBMC expressing L-selectin was lower in cattle with persistent lymphocytosis than in non-lymphocytotic or BLV-free cattle, and inversely correlated with lymphocyte counts. The ratio of B lymphocytes stained for L-selectin was significantly decreased from 60.2 +/- 1.9% in BLV-free cattle to 43.8 +/- 3.6 and 22.5 +/- 5.7% in non-lymphocytotic and lymphocytotic cattle, respectively. B-lymphocytes stained for L-selectin exhibited about 50% reduction in L-selectin expression in BLV-infected cattle compared with BLV-free cattle, as judged by the mean fluorescence intensity (MFI). The percentage of L-selectin-positive PBMC not bearing surface immunoglobulin M (predominantly T lymphocytes) was comparable in BLV-free and BLV-infected cattle. However, L-selectin expression on T lymphocytes was reduced (about 50%) in BLV-infected cattle, as judged by the MFI. We suppose that BLV infection results in a decreased L-selectin expression on lymphocytes, and accordingly, it may contribute to deregulation of the host immune system.  相似文献   
9.
Anholocyclic strains ofSitobion avenae (F.),Rhopalosiphum padi (L.) andRhopalosiphum maidis (Fitch) were detected on winter barley and wheat in autumn, 1995 in South Moravia, the Czech Republic. Anholocycly was proved by samples docummenting the species composition and population structure of aphids in 20 localities throughout the area. Natural enemy presence was also determined and the species are listed. Anholocycly established in the cereal aphids in the target area is discussed in relation to a similar evidence known from the north-west Europe and some parts of the Mediterranean.  相似文献   
10.
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