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Outdoor production of poultry is rapidly increasing, which could be associated with increased risks for exposure to different environmental sources of Salmonella. We report a comparison on the occurrence of Salmonelladuring 2007–2015 in broilers and laying hens in outdoor and indoor production subjected to the same requirements for the prevention and control of Salmonellaas applied in Sweden. Our results give no indication that, during the period studied, the exposure to Salmonellain outdoor poultry production was higher than in the indoor production. The annual incidence of Salmonellainfected flocks in outdoor production remained at a very low and at a similar level as for indoor production. For laying hens the annual proportion of birds in test positive flocks ranged from 0 to 1.3% for indoor production from 0 to 2.0% for outdoor production. For broilers the proportion of Salmonellainfected flocks (2013–2015) was 0.16% for indoor, and 0% in outdoor production. The difference was not statistically significant and was further reduced when flocks infected due to vertical transmission or from a hatchery source were excluded. It should, however, be considered that the number of outdoor flocks included in this evaluation is very small and continuous evaluation is needed. New animal production systems, including those driven by consumer and welfare demands, may be associated with a higher risk for the exposure of potential pathogens to food animals and possibly also subsequent outbreaks of food borne infections. In this study no increase in the risk for exposure of flocks to Salmonellain outdoor poultry production was found. The situation may well change and the possibility of Salmonellacontamination in outdoor poultry production requires continuous attention.

The Swedish control program for salmonella includes restrictions and on-farm control measures when salmonella is detected in a herd. Required control measures are subsidised by the government. This provides an opportunity to study costs for on-farm salmonella control. The aim of this study was to describe the costs for on-farm salmonella control in Swedish cattle herds and to investigate the effects of herd factors on these costs in dairy herds. During the 15 years studied there had been a total of 124 restriction periods in 118 cattle herds; 89 dairy herds, 28 specialised fattening herds and three suckler herds. The average costs per herd for on-farm salmonella control was 4.60 million SEK with a median of 1.06 million SEK corresponding to approximately 490 000 and 110 000 EUR. The range was 0.01 to 41 million SEK corresponding to 1080 EUR to 4.44 million EUR per farm. The costs cover measures required in herd-specific control plans, generally measures improving herd hygiene. A mixed linear model was used to investigate associations between herd factors and costs for on-farm salmonella control in dairy herds. Herd size and length of the restriction period were both significantly associated with costs for on-farm control of salmonella with larger herds and longer periods of restrictions leading to higher costs. Serotype detected and administrative changes in the Swedish Board of Agriculture aiming at reducing costs were not associated with costs for on-farm salmonella control. On-farm control of salmonella in Swedish cattle herds incurred high costs but the costs also varied largely between herds. Larger herds and longer restriction periods increased the costs for on-farm control of salmonella in Swedish dairy herds. This causes concern for future costs for the Swedish salmonella control program as herd sizes are increasing.

The prevalence of Salmonellain food producing animals is very low in Sweden due to rigorous control programmes. However, no active surveillance is in place in sheep. The authorities decided to perform a prevalence study in sheep herds because findings at slaughter indicated that sheep associated S. diarizonae(S. entericasubspecies diarizonaeserovar 61:(k):1, 5, (7)) might be common in sheep. Sampling was stratified by herd size in two groups, small herds with ≤ 30 animals and large herds with > 30 animals. In each stratum, 237 herds were selected at random. Faecal samples received from 244 out of the 474 randomly selected herds were analysed. A total of 40 of 100 (40%) of large herds and 17 of 144 (12%) of small herds were positive. The overall adjusted prevalence was 17.6% (95% CI, 12.9-22.2). Sheep associated S. diarizonaewas detected in all counties (n= 21). Scientific opinions and an evaluation of on-farm control measures performed concluded that the impact of sheep associated S. diarizonaeon human health is very low, and that risk management measures applied in response to findings of sheep associated S. diarizonaein sheep or sheep meat can be expected to have very little impact on reducing risks to human health. As a result, Swedish authorities decided to make an exemption for sheep associated Salmonella diarizonaein sheep and sheep meat in the current Salmonellacontrol measures. Sheep associated S. diarizonaeis endemic in Swedish sheep herds. It is more common in large herds and not limited to certain parts of the country. The responsible authorities concluded that current risk management actions regarding sheep associated S. diarizonaein sheep and sheep meat are not proportional to the risk. This is the first time in the history of the Swedish Salmonellacontrol programme that an exemption from the legislation has been made for a specific serovar. If there is any future indication of an increasing risk, due to e.g.change in the pathogenicity or development of antimicrobial resistance, the risk assessment will be re-evaluated and control measures reinforced if needed.

The Swedish Salmonellacontrol program has been running for decades and has resulted in a low prevalence of Salmonellain Swedish food producing animals. Routine bacteriology is used to detect Salmonella, however, bacteriology is time consuming, costly and has a low sensitivity. Different enzyme-linked immunosorbent assays (ELISAs) have been developed for detection of antibodies against SalmonellaDublin and S. Typhimurium in bovine bulk milk, individual milk samples as well as in sera. Screening bulk milk for antibodies against Salmonellaspp. could improve the cost-effectiveness of the surveillance in Swedish dairy cattle, but as characteristics of tests may vary in different populations, tests should always be evaluated in the specific population where they will be used. Hence, the aim of this study was to evaluate the specificities of three bovine ELISAs when used to analyse bulk milk samples from Swedish dairy cattle. A second aim was to compare the performance of the two Dublin ELISAs tested.

The Swedish salmonella control programme covers the entire production chain, from feed to food. All salmonella serotypes are notifiable. On average, less than 20 cases of salmonella in food-producing animals are reported every year. In some situations, the cases would be expected to cluster geographically. The aim of this study was to illustrate the geographic distribution of the salmonella cases detected in pigs, cattle and sheep.

The fox tapeworm Echinococcus multilocularis has foxes and other canids as definitive host and rodents as intermediate hosts. However, most mammals can be accidental intermediate hosts and the larval stage may cause serious disease in humans. The parasite has never been detected in Sweden, Finland and mainland Norway. All three countries require currently an anthelminthic treatment for dogs and cats prior to entry in order to prevent introduction of the parasite. Documentation of freedom from E. multilocularis is necessary for justification of the present import requirements.

This paper presents Salmonella data from animals, feedstuffs and feed mills in Sweden between 1993 and 1997. During that period, 555 isolates were recorded from animals, representing 87 serotypes. Of those, 30 serotypes were found in animals in Sweden for the first time. The majority of all isolates from animals were S. Typhimurium (n = 91), followed by S. Dublin (n = 82). There were 115 isolates from cattle, 21 from broilers, 56 from layers and 18 from swine. The majority of these isolates were from outbreaks, although some were isolated at the surveillance at slaughterhouses. The number of isolates from the feed industry was similar to that of the previous 5-year period. Most of those findings were from dust and scrapings from feed mills, in accordance with the HACCP programme in the feed control programme. It can be concluded that the occurrence of Salmonellain animals and in the feed production in Sweden remained favourable during 1993–97.