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991.
Joiner KS Hoerr FJ Ewald SJ van Santen VL Wright JC van Ginkel FW Toro H 《Avian diseases》2007,51(3):758-763
Infectious bronchitis (IB) disease progression in vaccinated chickens after challenge was evaluated in a single commercial line of layer chickens presenting two different major histocompatibility complex (MHC) B complex genotypes. MHC B genotypes were determined by DNA sequence-based typing of BF2 alleles. In total, 33 B2/B15 and 47 B2/B21 chickens were vaccinated with an Ark-type IB virus (IBV) attenuated vaccine and challenged with Ark-type IBV field isolate AL/4614/98 14 days later. Additional chickens of both genotypes served as unvaccinated/challenged and unvaccinated/nonchallenged controls. Clinical signs, histopathologic analysis, detection of IBV genomes in tears, and IBV-specific immunoglobulin A (IgA) in tears were used to evaluate disease progression and immune response. The incidence of IBV respiratory signs was significantly higher in B2/21 than in B2/B15 MHC genotype birds. However, neither the severity and duration of respiratory signs nor the severity and incidence of histologic lesions differed significantly with MHC genotype. The levels of IBV-specific IgA in tears of vaccinated and challenged chickens did not differ significantly between MHC genotypes. IBV genomes were present in the tears of vaccinated and challenged birds, and the incidence of detectable IBV genomes did not vary significantly with MHC B genotype. From an applied perspective, these results indicate that vaccinated commercial outbred chickens with these MHC genotypes are equally resistant to IBV. 相似文献
992.
REASONS FOR PERFORMING STUDY: Previous studies have suggested that temporomandibular joint (TMJ) kinematics depend on the type of food being masticated, but accurate measurements of TMJ motion in horses chewing different feeds have not been published. HYPOTHESIS: The temporomandibular joint has a larger range of motion when horses chew hay compared to pellets. METHODS: An optical motion capture system was used to track skin markers on the skull and mandible of 7 horses as they chewed hay and pellets. A virtual marker was created on the midline between the mandibles at the level of the 4th premolar teeth to represent the overall motion of the mandible relative to the skull during the chewing cycle. RESULTS: Frequency of the chewing cycles was lower for hay than for pellets. Excursions of the virtual mandibular marker were significantly larger in all 3 directions when chewing hay compared to pellets. The mean velocity of the virtual mandibular marker during the chewing cycle was the same when chewing the 2 feeds. CONCLUSIONS: The range of mediolateral displacement of the mandible was sufficient to give full occlusal contact of the upper and lower dental arcades when chewing hay but not when chewing pellets. POTENTIAL RELEVANCE: These findings support the suggestion that horses receiving a diet high in concentrate feeds may require more frequent dental prophylactic examinations and treatments to avoid the development of dental irregularities associated with smaller mandibular excursions during chewing. 相似文献
993.
Incisional complications following exploratory celiotomy: does an abdominal bandage reduce the risk?
REASONS FOR PERFORMING STUDY: Post operative complications following exploratory laparotomy can be potentially life-threatening, increase post operative morbidity and result in an increase in the length of hospitalisation of the affected individual. No study has evaluated the efficacy of specific strategies to reduce the incidence of post operative incisional complications. HYPOTHESIS: The use of an abdominal bandage following colic surgery through a celiotomy incision would significantly reduce the prevalence of post operative incisional complications. METHODS: A controlled, randomised clinical trial to test the hypothesis was devised. Horses eligible for inclusion in the study were assigned randomly either to the study or control group following recovery from general anaesthesia. Any post operative incisional complications occurring during hospitalisation were recorded. Long-term follow-up was obtained via telephone questionnaires. Absolute risk reduction (ARR) and number needed to treat (NNT) were calculated. Multivariable analyses were conducted for all outcomes of interest. RESULTS: There was an ARR of the likelihood of developing a post operative incisional complication of 45% when using compared to not using an abdominal bandage in the post operative period. Therefore, it would be necessary to treat 2.2 horses with an abdominal bandage in order to prevent one horse developing any post operative incisional complications. CONCLUSIONS: Although incisional complications continue to be a problem following an exploratory celiotomy for colic, the proportion of horses affected was significantly reduced by use of a bandage. POTENTIAL RELEVANCE: Using an abdominal bandage following an exploratory laparotomy may help reduce the prevalence of post operative incisional complications, and prevent the development of potentially life-threatening complications. 相似文献
994.
995.
Silva EF Brod CS Cerqueira GM Bourscheidt D Seyffert N Queiroz A Santos CS Ko AI Dellagostin OA 《Veterinary microbiology》2007,121(1-2):144-149
The main goal of this study was to obtain new isolates of Leptospira spp. from sheep. A total of 10 kidney samples and 44 blood samples were collected from sheep slaughtered in Pelotas, Southern Brazil. One isolate was obtained which was identified by 16S rRNA gene sequencing and serogrouping to be Leptospira noguchii serogroup Autumnalis. Microscopic agglutination test (MAT) evaluation revealed that 4.5% of the sheep sera reacted against the Autumnalis serogroup. This is the first report of isolation of L. noguchii from sheep. Together these findings indicate that L. noguchii infections may be a potentially important veterinary problem in this domestic animal species. 相似文献
996.
Antúnez K Piccini C Castro-Sowinski S Rosado AS Seldin L Zunino P 《Veterinary microbiology》2007,124(1-2):178-183
Paenibacillus larvae is the causative agent of American Foulbrood (AFB), a severe disease of honeybees (Apis melifera). The aim of this work was to develop a strategy for the subtyping and the epidemiological analysis of P. larvae. Phenotypic characterisation, susceptibility to several antibiotics, electrophoresis of whole bacterial proteins, rep-PCR, ribotyping and DGGE were assessed using a collection of P. larvae isolates from different Uruguayan and Argentinean locations. Results indicated that there are two P. larvae genotypes circulating in Uruguay ERIC I-BOX A (worldwide distributed) and ERIC I-BOX C (exclusively detected in Argentina until this study). These results suggest that P. larvae isolates had moved between Argentina and Uruguay, probably through the Uruguay River. Patterns of whole bacterial proteins, DGGE and ribotyping did not improve the P. larvae intraspecific discrimination. Antibiotic susceptibility assays showed that 100% isolates were OTC-sensitive and 22% (belonging to ERIC I-BOX A group) were sulfisoxazole-resistant. This work may contribute to the elucidation of basic aspects related to the epidemiology of AFB in Uruguay and in the region. 相似文献
997.
The objective of this study was to test for correlations between alopecia and ruminal drinking in young calves. 331 calves up to an age of 31 days were tested for evidence of generalized hair loss daily during their stay in the clinic. Incidence of diarrhoea and the results of ruminal fluid and blood analysis were compared between the groups with and without alopecia. Calves with alopecia showed a significantly higher incidence of diarrhoea and of ruminal acidosis persisting for at least 24 hours. Blood analysis revealed significant differences in degree of acidosis, in concentrations of D-lactate, urea, and creatinine in serum as well as in the activities of glutathione peroxidase, aspartate amino transferase, and creatine kinase. Alopecia in calves is correlated to longer periods of diseases, which are known to be accompanied by the production of D-lactate in the gastrointestinal tract, such as diarrhoea and ruminal drinking. The question, whether alopecia is due to formation of toxic substances or to deficiency of essential substances can not be answered. 相似文献
998.
Diallo IS Hewitson G Wright LL Kelly MA Rodwell BJ Corney BG 《Veterinary microbiology》2007,123(1-3):93-103
A multiplex real-time PCR was designed to detect and differentiate equid herpesvirus 1 (EHV-1) and equid herpesvirus 4 (EHV-4). The PCR targets the glycoprotein B gene of EHV-1 and EHV-4. Primers and probes were specific to each equine herpesvirus type and can be used in monoplex or multiplex PCRs, allowing the differentiation of these two closely related members of the Alphaherpesvirinae. The two probes were minor-groove binding probes (MGB) labelled with 6-carboxy-fluorescein (FAM) and VIC for detection of EHV-1 and EHV-4, respectively. Ten EHV-1 isolates, six EHV-1 positive clinical samples, one EHV-1 reference strain (EHV-1.438/77), three EHV-4 positive clinical samples, two EHV-4 isolates and one EHV-4 reference strain (EHV-4 405/76) were included in this study. EHV-1 isolates, clinical samples and the reference strain reacted in the EHV-1 real-time PCR but not in the EHV-4 real-time PCR and similarly EHV-4 clinical samples, isolates and the reference strain were positive in the EHV-4 real-time PCR but not in the EHV-1 real-time PCR. Other herpesviruses, such as EHV-2, EHV-3 and EHV-5 were all negative when tested using the multiplex real-time PCR. When bacterial pathogens and opportunistic pathogens were tested in the multiplex real-time PCR they did not react with either system. The multiplex PCR was shown to be sensitive and specific and is a useful tool for detection and differentiation of EHV-1 and EHV-4 in a single reaction. A comprehensive equine herpesvirus disease investigation procedure used in our laboratory is also outlined. This procedure describes the combination of alphaherpesvirus multiplex real-time PCR along with existing gel-based PCRs described by other authors. 相似文献
999.
Daly JM Sindle T Tearle J Barquero N Newton JR Corning S 《Equine veterinary journal》2007,39(5):446-450
REASONS FOR PERFORMING STUDY: Surveillance of equine influenza viruses has suggested that strains included in currently licensed vaccines are a poor match for those predominantly circulating in the field. OBJECTIVE: To assess the ability of Duvaxyn IE-T Plus to provide cross protection against the newly evolved South Africa/4/03 (H3N8) strain of equine influenza virus. METHODS: The vaccine efficacy was evaluated by challenge infection with influenza strain A/eq/South Africa/4/03 (H3N8) 2 weeks after a primary course of 2 vaccinations with Duvaxyn IE-T Plus given at a 4-week interval. The outcome of challenge in vaccinated ponies was compared with that in unvaccinated animals. RESULTS: At the time of challenge, all vaccinated ponies had high levels of antibody to Newmarket/1/93, Newmarket/2/93 and South Africa/4/03 strains measured by single radial haemolysis. After challenge infection, there were statistically significantly decreased clinical scores and virus shedding was significantly lower in the vaccinated ponies compared to unvaccinated controls. CONCLUSION: Two doses of Duvaxyn IE-T Plus provides good clinical and virological protection against challenge with a variant virus 2 weeks after the 2 doses of vaccine. POTENTIAL RELEVANCE: When variant strains of equine influenza virus first emerge, booster immunisations with currently available vaccines may limit infection provided sufficiently high antibody levels are achieved, suggesting that vaccination in the face of an outbreak may be beneficial. 相似文献
1000.
Long MT Gibbs EP Mellencamp MW Zhang S Barnett DC Seino KK Beachboard SE Humphrey PP 《Equine veterinary journal》2007,39(6):486-490
REASON FOR PERFORMING STUDY: West Nile virus (WNV) infection is endemic and able to cause disease in naive hosts. It is necessary therefore to evaluate the safety of new vaccines. OBJECTIVES: To establish: 1) the safety of a modified live Flavivirus/West Nile virus (WN-FV) chimera by administration of an overdose and testing for shed of vaccine virus and spread to uninoculated sentinel horses; 2) that this vaccine did not become pathogenic once passaged in horses; and 3) vaccine safety under field conditions. METHODS: There were 3 protocols: 1) In the overdose/shed and spread study, horses were vaccinated with a 100x immunogenicity overdose of WN-FV chimera vaccine and housed with sentinel horses. 2) A reversion to virulence study, where horses were vaccinated with a 20x immunogenicity overdose of WN-FV chimera vaccine. Horses in both studies were evaluated for abnormal health conditions and samples obtained to detect virus, seroconversion and dissemination into tissues. 3) In a field safety test 919 healthy horses of various ages, breeds and sex were used. RESULTS: Vaccination did not result in site or systemic reactions in either experimental or field-injected horses. There was no shed of vaccine virus, no detection of vaccine virus into tissue and no reversion to virulence with passage. CONCLUSIONS: WN-FV chimera vaccine is safe to use in horses with no evidence of ill effects from very high doses of vaccine. There was no evidence of reversion to virulence. In addition, administration of this vaccine to several hundred horses that may have been previously exposed to WNV or WNV vaccine resulted in no untoward reactions. POTENTIAL RELEVANCE: These studies establish that this live attenuated Flavivirus chimera is safe to use for immunoprophylaxis against WNV disease in horses. 相似文献