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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
965.
Marcilla MG Schauvliege S Segaert S Duchateau L Gasthuys F 《Veterinary anaesthesia and analgesia》2012,39(1):49-58
ObjectiveTo investigate the influence of a dexmedetomidine constant rate infusion (CRI) in horses anaesthetized with isoflurane.Study designProspective, randomized, blinded, clinical study.AnimalsForty adult healthy horses (weight mean 491 ± SD 102 kg) undergoing elective surgery.MethodsAfter sedation [dexmedetomidine, 3.5 μg kg?1 intravenously (IV)] and induction IV (midazolam 0.06 mg kg?1, ketamine 2.2 mg kg?1), anaesthesia was maintained with isoflurane in oxygen/air (FiO2 55–60%). Horses were ventilated and dobutamine was administered when hypoventilation [arterial partial pressure of CO2 > 8.00 kPa (60 mmHg)] and hypotension [arterial pressure 70 mmHg] occurred respectively. During anaesthesia, horses were randomly allocated to receive a CRI of dexmedetomidine (1.75 μg kg?1 hour?1) (D) or saline (S). Monitoring included end-tidal isoflurane concentration, cardiopulmonary parameters, and need for dobutamine and additional ketamine. All horses received 0.875 μg kg?1 dexmedetomidine IV for the recovery period. Age and weight of the horses, duration of anaesthesia, additional ketamine and dobutamine, cardiopulmonary data (anova), recovery scores (Wilcoxon Rank Sum Test), duration of recovery (t-test) and attempts to stand (Mann–Whitney test) were compared between groups. Significance was set at p < 0.05.ResultsHeart rate and arterial partial pressure of oxygen were significantly lower in group D compared to group S. An interaction between treatment and time was present for cardiac index, oxygen delivery index and systemic vascular resistance. End-tidal isoflurane concentration and heart rate significantly increased over time. Packed cell volume, systolic, diastolic and mean arterial pressure, arterial oxygen content, stroke volume index and systemic vascular resistance significantly decreased over time. Recovery scores were significantly better in group D, with fewer attempts to stand and significantly longer times to sternal position and first attempt to stand.Conclusions and clinical relevance A dexmedetomidine CRI produced limited cardiopulmonary effects, but significantly improved recovery quality. 相似文献
966.
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
967.
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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970.
Sameh A. Abdelnour Mohamed E. Abd El‐Hack Mahmoud Alagawany Mayada R. Farag Shaaban S. Elnesr 《Journal of animal physiology and animal nutrition》2019,103(2):477-484
Bee pollen (BP) is one of the most useful therapeutic products favoured by natural medicine scientists because of its possible nutritional and medical applications. It exhibits many impacts such as antimicrobial, immunostimulating, antioxidants and hepatoprotective. Furthermore, BP has some useful therapeutic features in numerous pathological situations such as its impact to normalize wound healing. Based on previous literatures, the level of BP supplement in livestock and poultry ranged from 0.1 to 20 g/kg diet. This variation depends on the species, physiological status, age and purpose of addition; so far generally, it accepted to use the level with no side effects. It has been observed that BP enhanced growth performance, immunity responses and blood variables and had hypoglycaemic activity by reducing the lipid in the blood and carcass. Also, BP contains more nutrients, which stimulate faster differentiation and proliferation of the cells of immune system of birds. Therefore, the present review recommends that BP supplementation (up to 20 g/kg diet) had possible beneficial impacts, antioxidants and protective activities on most of the production, productive and health patterns of livestock. 相似文献