Epidemiological evaluation of the salmonella-controlling effect of a nationwide use of a competitive exclusion culture in poultry.

The purpose of the study was to evaluate the salmonella contamination-controlling effect of a nationwide use of a competitive exclusion culture in poultry. During a 5-yr period, a bacterial flora from caecum of adult birds was given to broiler chickens in order to control salmonella infection. The culture was given on 144 occasions to a total of 2.86 million chickens. The base for the evaluation was the compulsory and regular control for salmonella contamination conducted according to the salmonella control program applied to Sweden. Epidemiological evaluation, especially in relation to the use of the culture during a period when salmonella was spread from a feed factory, strongly supports the conclusion that the culture has a salmonella contamination-preventing effect under field conditions, as earlier had been found in laboratory studies. Questionnaires answered by producers did not indicate significant adverse effects of the treatment.

Animal consumption of antibiotics and chemotherapeutic drugs in Sweden during 1980, 1982 and 1984.

The total animal consumption of antibiotic and chemotherapeutic drugs in Sweden during 1980, 1982 and 1984 has been studied. The study also included coccidiostatic, antiparasitic and antimycotic drugs. The total animal consumption during the years mentioned was 66.1, 68.8 and 72.6 tons of active substance, respectively, and the amount of antibacterial drugs for therapy was 28.7 (43.4%), 29.1 (42.5%) and 34.1 (47.0%) tons, respectively. Tetracycline, penicillin, sulphonamide and aminoglycoside were the four major groups of antibiotics used for therapy of bacterial infections in animals. The consumption was related to the metabolic bodyweights of animals which were the potential consumers. A comparison was also made with the corresponding human consumption during 1980. The data on antibiotic consumption can be divided by county and compared to the animal population and disease situation in each county. This study thus offers a good base for further investigations on different aspects of the use of antibiotics.

Benefit/cost aspects on voluntary control of bovine leukosis.

An organized voluntary control of bovine leukosis, motivated by export interests, has existed in Sweden since 1969. Owing to reduced prospects for export, the economic justification for the control has been questioned. The present study comprises programs and economical calculations for a twenty-year period and considering three different modes of action, namely A. Continued organized control. B. Discarding of all precautionary measures. C. Private voluntary control based on herd examination and certain precautions in restocking routines. Cost/benefit ratios, net present value (NPV), and effective interest rate (IRR) have been calculated. Profitability throughout was found to be worst in alternative A, similar in the B and C alternatives at a low export rate, and best in alternative C in the case where exports comprise at least 60 animals per year.