PubMed · 15154717
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
Kate O'Rourke. 2004-05-15. Evaluating humane slaughter.. https://pubmed.ncbi.nlm.nih.gov/15154717/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
OBJECTIVES: Two multiresistant Salmonella enterica subsp. enterica serovar Agona isolates from pig carcasses were investigated for antimicrobial resistance genes and their location with particular reference to the detection of class 1 integrons. METHODS: The two S. Agona isolates were investigated for their in vitro susceptibility to antimicrobial agents and their plasmid content. The resistance genes and class 1 amplicons were identified by PCR assays. Amplicons of class 1 integrons were cloned and sequenced. Transferability of resistance plasmids was confirmed by conjugation. RESULTS: Both S. Agona isolates carried conjugative plasmids of approximately 150 kb which harboured all resistance genes detected in the respective isolates. S. Agona 231 was resistant to chloramphenicol by catA1, to tetracycline and minocycline by tet(B), and to sulphonamides by sul1. In addition, it harboured a streptomycin resistance gene strA and a class 1 integron with a new aadA variant designated aadA23, which mediates resistance to streptomycin and spectinomycin. S. Agona 242 also carried the genes catA1, tet(B), and sul1. Moreover, it harboured a second sulphonamide resistance gene, sul2, and a class 1 integron with intact gene cassettes carrying new variants of the trimethoprim resistance gene dfrA15b or the chloramphenicol resistance gene cmlA4. The third gene cassette consisted of a truncated aadA2 gene. CONCLUSIONS: The results of this study show that large conjugative multiresistance plasmids are present in S. Agona from pigs. Analysis of the class 1 integrons revealed the presence of new variants of resistance genes so far not detected in Salmonella isolates.
After the foot-and-mouth disease (FMD) epidemic in Dumfries and Galloway in south-west Scotland in 2001, serosurveillance of sheep remaining in the 3 km radius Protection Zones around Infected Premises (IPS), and within a 10 km radius of IPS, revealed no evidence of infection. The epidemic was brought under control by a range of traditional techniques: slaughter of all animals on IPS and of veterinary-assessed Dangerous Contacts (DCS), movement restrictions, biosecurity, tracing of potential sources and spread of virus, and surveillance of At-Risk premises. Novel pre-emptive slaughter of FMD-susceptible animals on premises contiguous to IPS, and small ruminants and pigs on premises within 3 km of IPSs, commenced after the epidemic had peaked. Most of the traditional control procedures were undertaken quickly and with appropriate priority. Animals on IPS were usually slaughtered within one day of confirmation, and veterinary-assessed DCS within two days of confirmation of relevant IPS (a median of two days). The pre-emptive contiguous and 3 km culls took somewhat longer (medians of five and 17 days, respectively). IPS were most commonly identified as a result of reporting by farmers or their veterinarians (72 per cent of IPS); veterinary clinical patrols identified 16 per cent, while veterinary assessment of DCS and tracing each identified 5 per cent. No evidence of infection was found on any pre-emptively contiguously culled premises, and IPS were declared only on three 3 km cull premises. The time from estimated first lesion to end of slaughter on an IP was found, by regression analysis, to be a key component in effective control, manifested by a reduction in the estimated dissemination rate (EDR); there was little evidence that the intensity of contiguous culling affected the EDR. Patrols and serological surveillance of residual animals within 10 km of IPS, supported by more extensive evidence from elsewhere in the UK, suggested that cryptic infection in sheep was not widespread. Ultimately, there was insufficient evidence to support the effectiveness of 3 km pre-emptive culling as a control procedure.
The present study investigates the combined effects of feed-induced increase in polyunsaturated fatty acids (PUFA) content and/or alpha-tocopherol content in pig muscles and preslaughter stress on cell integrity. Cell integrity was determined by plasma lactate dehydrogenase (LDH) activity, and antioxidative status of muscle was measured by activities of the antioxidative enzymes catalase, superoxide dismutase, and glutathione peroxidase. Preslaughter stress increased LDH activity, reflecting loss in cell membrane integrity independent of increased content of PUFA and/or alpha-tocopherol. However, feed-induced increase of PUFA decreased the LDH activity in plasma immediately after slaughter. Catalase activity in the muscle tissue increased as a consequence of the high-PUFA diet, which may indicate an increased demand caused by introduction of oxidative labile PUFA.