[Detection of antibiotics and/or chemotherapeutic agents in slaughtering pigs by a captive impedance measurement using the M 120 Bactometer]. / Het aantonen van antibiotica- en/of chemotherapeutica in slachtvarkens door middel van capacitieve impedantiemeting met een Bactometer M 120.

A study was performed to compare the use of capacitive impedance measurement with EEC 4-plate method for the detection of antibacterial residues. Urine, meat, kidney and spleen were the matrices used in the impedance measurement. Meat was used in the EEC 4-plate method. Capacitive impedance measurement is quick, relatively simple, and reliable method, in which objective interpretation of the test results is guaranteed by automatic apparatus. Using meat and kidney as matrices, the test appears to be an efficient screening test for export meat and edible offal. As far as domestic Meat Inspection legislation is concerned, the test described may provide more specific information than the methods presently in use.

Survival of Campylobacter jejuni during Poultry Processing and Pig Slaughtering.

Experiments were done to assess the survival of Campylobacter jejuni during different stages of poultry processing and pig slaughtering. Natural sources of Campylobacter contamination, i.e., spinchiller water, chicken intestinal contents and pig feces, were used for this purpose. C. jejuni in chicken intestinal contents had D-values ranging from 0.18 to 0.39 min at 60°C to 1.96 to 10.82 min at 52°C. Experiments with surfaces of pig carcasses contaminated with pig feces and held in the cooling room of a pig slaughterhouse showed an overnight reduction of Campylobacter until below the detection level. Further experiments in the laboratory showed that this reduction was due to drying of the skin surface. C. jejuni was very sensitive to drying. When contaminated spinchiller water was spread on tiles of different materials (aluminium, stainless steel, Formica and ceramic), the organism survived as long as a moistened surface could be observed. They could not be isolated once surfaces were visually dry. Freezing affected C. jejuni only during the first few hours; after an initial drop of number, Campylobacter could survive on chicken carcasses and chicken livers at -20°C for more than 64 and 84 d, respectively.

[A semi-solid enrichment medium in the isolation of Salmonella from minced meat (author's transl)]. / Het isoleren van Salmonellae uit gemalen vlees met behulp van een halfvast selectief ophopingsmedium.

A semi-solid enrichment medium as described by Chau and Huang (4) was modified and tested for suitability to isolate Salmonella from minced meat. The technique was found to be more rapid (averaging one day) as well as more sensitive than the usual technique with tetrathionate brilliant green bile broth incubated at 43% C (2.2 per cent more isolations).

[The effect of resuscitation on the results obtained in identification of enterobacteriaceae by the API system (author's transl)]. / De invloed van resuscitatie op de resultaten bij identificatie van entero-bacteriaceae met het analytical profile index (A.P.I)-systeem.

During studies on the reliability of the API system, the question arose whether the small proportion of adequate results in cultures stored at 4 degrees C could be attributable to this method of storage. Therefore, the reactions of those cultures which had caused most problems were studied following periods of storage ofone day, six weeks and nine weeks at 4 degrees C, and in the freeze-dried state. Storage in particular conditions was found to have a definite effect on the reliability of the API system so that a period of resuscitation of forty-eight hours in a bouillon at 37 degrees C is required to restore the cultures to normal.