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Pork has been traditionally considered an important source of human Toxoplasma gondii infection. Pigs, as other meat‐producing animals, can become infected by the ingestion of oocysts that are shed in the environment by infected cats or by the consumption of cysts present in tissues of infected mammals, commonly small rodents. The objective of this study was to investigate the level of T. gondii infection in swine from southern Chile that can be associated with the ingestion of oocysts and therefore exposure to a contaminated environment. A total of 340 serum samples from swine were obtained from three commercial slaughterhouses located in the Araucania and Los Rios Regions from southern Chile. Study animals originated from local farms, mainly small commercial producers, and the meat is sold locally. Overall, 8.8% (30/340) of the samples showed T. gondii‐specific IgG antibodies. Of these sero‐positive animals, 80% (24/30) were also positive for antibodies specific against the oocyst stage of the parasite, indicating that animals had been infected recently by the ingestion of oocysts. The observed results suggest a high level of environmental contamination with oocysts on the farms of origin. In addition to the food safety problems associated with the consumption of meat from infected animals, the high level of environmental contamination on the farm represents a direct health risk for people living and/or working on these farms. Consequently, there is a need to develop on‐farm monitoring programmes and identify risk reduction strategies (food storage, water purification, rodent control and contact with cats) that are appropriate and cost‐effective for informal and outdoor type of farms. 相似文献
905.
Gil de los Santos JR Storch OB Fernandes CG Gil-Turnes C 《Veterinary microbiology》2012,156(3-4):448-451
The probiotic properties of Pichia pastoris and of a recombinant P. pastoris containing the Clostridium perfringens alpha toxin gene were evaluated in broilers. One-day-old chicks randomly divided in four groups were fed with commercial feed devoid of antibacterials. The control group (1) received plain food, while the other groups were supplemented with either P. pastoris (2), the recombinant P. pastoris (3) or Bacillus cereus var. Toyoi (4). At day 49, live weights, feed efficiency and seroconversions were higher (P<0.05) in the supplemented groups than in the control groups. Group 3 showed the best results, while group 2 had lower weight gain than groups 3 and 4 although food conversion was better than in group 4. Seroconversions were not different (P>0.05) among the supplemented groups. Adverse reactions were not observed in histopathologic evaluation. We concluded that P. pastoris and the recombinant P. pastoris could be used as probiotics in broilers. 相似文献
906.
Jack‐Yves Deschamps Jean‐Michel Gaulier Guillaume Podevin Yan Cherel Nicolas Ferry Françoise A Roux 《Veterinary anaesthesia and analgesia》2012,39(6):653-656
Case history and presentationTwo non-human primates (Macaca fascicularis), weight 3.5 kg, enrolled in an experimental protocol received a 25 μg hour?1 transdermal fentanyl patch for postoperative analgesia. The following day both animals were clinically normal, but after a new induction of anaesthesia with ketamine, they developed severe and prolonged respiratory distress, profound coma and myosis.Management and follow-upAttempted reversal with naloxone was ineffective. After several hours of ventilation, both primates eventually died, 7 and 15 hours after ketamine injection, respectively. In both cases, the patch was discovered in the animal's cheek pouch. Subsequent fentanyl serum concentration measurements (8.29 and 14.80 μg L?1) confirmed fentanyl overdose.ConclusionsThis report of two fatal intoxications in non-human primates secondary to ingestion of a transdermal fentanyl patch demonstrates that this method of analgesia is inappropriate for non-human primates, because of their tendency to chew almost anything they can reach. 相似文献
907.
T. Jaroensong Y. Endo S.‐J. Lee A. Kamida M. Mochizuki R. Nishimura N. Sasaki T. Nakagawa 《Veterinary and comparative oncology》2012,10(4):274-282
To determine the influence of the transplantation site of canine osteosarcoma (OS) cell lines on tumour growth and pulmonary metastasis, three OS cell lines were transplanted into nude mice via subcutaneous (SC), intratibial (IT) or intravenous (IV) injection. IT‐xenografts exhibited greater potential for developing primary masses and pulmonary metastasis than SC‐xenografts. In IT and IV xenografts, lung micrometastases along with phosphorylated ezrin–radixin–moesin (p‐ERM) overexpression were found in mice xenografted with HMPOS and OOS cells after 1 week and metastasis was found with decreased p‐ERM expression at later time points. The expression of ezrin and p‐ERM in the primary tumours of IT‐xenografted mice was higher than those in SC‐xenografted mice with HMPOS and OOS cells. The results suggest that the orthotopic transplantation site plays an important role in the spontaneous metastasis of canine OS and that ezrin phosphorylation may be involved in the early metastatic mechanism of canine OS cells. 相似文献
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