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131.
Occurrence of reproductive disorders in pig herds with and without Chlamydia suis infection – statistical analysis of breeding parameters 下载免费PDF全文
Krzysztof Rypuła Aleksandra Kumala Katarzyna Płoneczka‐Janeczko Paweł Lis Ewa Karuga‐Kuźniewska Krzysztof Dudek Ireneusz Całkosiński Patrycja Kuźnik Paweł Chorbiński 《Animal Science Journal》2018,89(5):817-824
Chlamydiae are frequently encountered Gram‐negative intracellular eubacteria that can cause clear manifestations or clinically asymptomatic disorders. C. suis and other chlamydia are primarily isolated in cases of reproductive disorders. This study was performed to estimate the impact of Chlamydia suis infection on reproduction in sows by analyzing reproduction rates and breeding parameters. The test was conducted on first generation (F1) pigs from Polish Landrace (PL) × Polish Large White (PLW). Sixty‐four herds were investigated and 500 vaginal swabs were collected. Isolation of DNA was carried out directly from the swabs. All samples were analyzed for Chlamydia suis by real‐time PCR with a locked nucleic acid (LNA)‐containing probe. To analyze the impact of chlamydia infection on reproductive parameters, evaluation questionnaires were used. Reproductive problems were found in 77.3% of the farms tested. The receiver operating characteristic curve indicated that in the farms with 10 up to 120 sows, there were higher reproductive problems with chlamydia infection than in smaller and bigger pig farms. The most common problems were estrus repetition, which was reported by 57.81% of the surveyed farms, and the birth of dead piglets, which was reported by 31.25% of the investigated pig farms. Abortions, which were reported by 28.12% of the surveyed farms, were the least common reproductive disorders. 相似文献
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Guillén Llera JL López García ML Martín Reinoso E De Vivar González R 《Veterinary parasitology》2002,109(3-4):185-190
A mixed indirect fluorescence antibody test (IFAT), based on cultured promastigotes Leishmania infantum and formol-inactivated suspension of cells infected with the bacteria Ehrlichia canis, was applied to make a differential diagnosis between canine ehrlichiosis and leishmaniosis. A titre greater than 80 was considered positive for antibodies to E. canis and suggestive of antibodies to L. infantum. Positive sera were titrated subsequently by serial dilutions to confirm antibodies positive to Leishmania and establishing the antibody titre of both pathogens. Fluorescence was absent with negative control sera and background staining was minimal. No serological cross-reactions between positive sera for L. infantum or E. canis were detected. Results obtained by mixed IFAT did not differ when the same serum IFAT standard was compared. The test showed equivalent sensitivity (100%). The specifities were 100% for L. infantum and 98.5% for E. canis. The equivalence in sensitivity was confirmed by calculating the correlation coefficient between IFAT standards and mixed IFAT (r>or=0.99 for both pathogens). The results of our investigations demonstrated that mixed IFAT is a specific means of establishing serological differential diagnosis of canine leishmaniosis and ehrlichiosis. 相似文献
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von Blumröder D Schares G Norton R Williams DJ Esteban-Redondo I Wright S Björkman C Frössling J Risco-Castillo V Fernández-García A Ortega-Mora LM Sager H Hemphill A van Maanen C Wouda W Conraths FJ 《Veterinary parasitology》2004,120(1-2):11-22
Various existing serological tests were compared with a standard panel of 523 sera in a multicentred study across Europe. Well characterised sera from animals that were experimentally or naturally infected with Neospora caninum as well as sera from cattle deemed uninfected with N. caninum were provided by the participants of the study and analysed in several commercial (CHEKIT Dr. Bommeli/Intervet, CIVTEST BOVIS NEOSPORA Hipra, Cypress Diagnostics C.V., Herd Check IDEXX, Mastazyme MAST Diagnostics, P38-ELISA Animal Welfare and Food Safety GmbH (AFOSA)) as well as in-house assays (five ELISAs and one IFAT). Most tests showed a high level of agreement in the interpretation of the test results (positive or negative). A further distinct increase in agreement between tests was obtained after the application of standardised cut-offs offered by a two-graph receiver operating characteristic analysis. This procedure allows a standardised interpretation of results obtained with different tests used in independent, parallel seroepidemiological studies. 相似文献
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Isabelle Ferreira Sheila C. Rahal Noeme S. Rocha Ana H. Gouveia† Thais P. Corrêa Yuri K. Carvalho Vanderlei S. Bagnato† 《Veterinary dermatology》2009,20(3):174-178
Photodynamic therapy (PDT) using a haematoporphyrin derivative (Photogem®, General Physics Institute and clustes Ltda) as photosensitizer and light emitting diodes (LEDs) as the light source was evaluated in 12 cats with cutaneous squamous cell carcinoma. Lesions were illuminated with LEDs, (300 J/cm for 30 min) 24 h after the administration of the photosensitizer. Clinical responses were classified as complete disappearance of the tumour with total re-epithelialization; partial response (a reduction greater than 50%); and no response (less than 50% reduction). Tumours localized to the pinna treated with one ( n = 3) or two ( n = 4) applications of PDT yielded no response. Highly invasive tumours of the nose and nasal planum also showed no response, after two treatments ( n = 2). A combination of PDT and surgery was performed in three cases. Two cats showed partial response and one complete response with one application of therapy 30 days after nasal surgery. Small and noninfiltrative lesions ( n = 3) of the nasal planum showed a PR with one application ( n = 2) and a CR with two applications ( n = 1). This study shows that PDT using Photogem® and LEDs can provide local control of low-grade feline squamous cell carcinoma. The addition of PDT to surgery in more invasive cases may help prevent recurrence. 相似文献
136.
María Fuentes-Rubio José J. Cerón Carlos de Torre Damián Escribano Ana M. Gutiérrez Fernando Tecles 《Canadian journal of veterinary research》2014,78(2):127-132
The purpose of this research was to study changes in the salivary proteome of healthy pigs in stressful situations to identify any potential new salivary biomarker of stress. Three groups of animals were subjected to 3 stress models: snaring restraint followed by simulated sampling of vena cava blood; brief transport by road; and restriction of movement in a digestibility cage. Saliva was obtained from each animal before and 15 and 30 min after the induction of stress. The samples from the animals that showed the greatest increase in salivary cortisol concentration were pooled and run on 2-dimensional gels. Coomassie Brilliant Blue R-250 was used for spot detection and mass spectrometry for spot identification. Statistical analyses showed that 2 proteins had significant differences in expression before and after the induction of stress. These proteins were identified as odorant-binding protein and fragments of albumin. Further studies will be necessary to confirm the value of using these proteins as salivary biomarkers of stress in pigs. 相似文献
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Structural development of Pacific red snapper Lutjanus peru from hatching to the onset of first feeding 下载免费PDF全文
Iram Zavala‐Leal Silvie Dumas Edgar O. López‐Villegas Renato Peña Mauricio Contreras‐Olguín Laura Flores‐Montijo José De La Cruz‐Agüero 《Aquaculture Research》2015,46(5):1162-1174
Successful rearing of larval fish requires culture conditions and feeding strategies matching the ontogenetic status of larvae. This study describes the external morphology and development of organs and structures involved in the feeding process (i.e. sensorial organs, mouthparts and digestive system) from hatching until first feeding in Pacific red snapper. Hatching occurred 26 h after fertilization at 26°C and total length (TL) was 2.45 ± 0.08 mm. The larvae showed an undifferentiated eye and digestive tract. At 48 hah, TL was 3.31 ± 0.12 mm. Yolk and oil globule were still present. The mouth was still closed, but the Meckel's, quadrate, hyoid and hyomandibular cartilages were present. The retina was formed by 5 layers, and a thin layer of pigment epithelium was observed in the outer nuclear layer (ONL). At 70 hah, TL was 3.44 ± 0.22 mm. A remnant of oil globule was still present. The mouth and anus were open. At 93 hah, the number of cones in the ONL of the retina have increased and there was more pigment in the pigment epithelial layer. A joint between Meckel's and the quadrate cartilage and also a joint between the hyomandibular cartilage and the skull were present. The presence of live feed was detected in the digestive tract of these larvae. Based on these observations, the Pacific red snapper larvae is functional to start ingesting live feed between the 3rd and 4th day after hatching. 相似文献