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This paper discusses the field experience obtained after the implementation of Salenvac vaccination in layers in the United Kingdom and in broiler breeders in The Netherlands. Based on the experience in both countries it is concluded that the use of the inactivated Salmonella Enteritidis vaccine Salenvac clearly reduced the spread of Salmonella.

The use of Flavomycin as part of a Salmonella control program is discussed and results of trial data presented

Salmonella shedding in a total of 36 416 BUT breeding turkeys was studied following intramuscular vaccination with Salenvac in two production cycles. Flock A received a 1ml dose twice i.m. at week 20 and 27. Flock B received a 0.5 ml dose of the vaccine three times at week 8, 20 and 27.

Before vaccination samples were taken because of production problems and10.6% were Salmonella positive. Eggs showed a high rate of Salmonella contamination. Seven out of 11 strains serotyped were identified as S. Enteritidis.

Vaccinated period: No Salmonella was isolated from day-old or growing poults. In flock B S. Enteritidis was isolated at week 52.

The ELISA test at week 54 indicated low serum antibody titres (positive=2, negative=201 and doubtful=74 out of 277 animals). Following the vaccination procedures Salmonella-associated losses and condemnations were reduced to one third of the level observed prior to vaccination. After vaccination the hatching performance improved, the quality of the day old poults was better and performance figures were higher.

The protective effect of two vaccination programs using Salenvac was verified in laying birds. Vaccination was intramuscular at 1 day old and again at 4 weeks of age (V2), or at 1 day and 4 weeks with a third dose at 18 weeks of age. (V3). At 8, 17, 23, 30 and 59 weeks of age, challenge S. Enteritidis (5 to 7,5) X 107 colony forming units was given intravenously . For all age groups, both vaccination programs reduced significantly the number of tissues and faecal samples that were culture positive for the challenge strain. For laying birds, fewer eggs (p<0.001) were culture positive for S. Enteritidis after challenge from vaccinated laying birds (56/439 batches of eggs) than unvaccinated birds (99/252 batches). The data gives compelling proof that the vaccine is efficacious and may contribute to the reduction of layer infection and egg contamination.

A live vaccine based on an attenuated Salmonella Gallinarum 9R strain is in use in a Salmonella Enteritidis control program in commercial layer flocks in The Netherlands. In a field study the potential spread of the vaccine strain from vaccinated flocks to non-vaccinated flocks was studied. No evidence was found for the fecal spread of the vaccine strain.

The high cost of rearing pathogen-free poultry, coupled with increases in importation from non-European countries where hygienic measures may be less stringent indicates that biological approaches to control of infection with food-borne pathogens will continue to be important. The major measures are dealt with in this review, together with the positive and negative aspects of these approaches. They include antibiotic therapy and prophylaxis, competitive exclusion using intestinal flora preparations, live and killed vaccines and the increasing interest in exploiting natural genetic resistance to infection and disease.

A study to measure the growth rate of Salmonella Enteritidis (SE) in eggs at different temperatures. SE was inoculated into the yolk and albumen, the growth was measured over two days at 4C, 8C, 15C, 27C, 37C.

SE counts in the albumen declined at 4C, 8C and 15C and remained constant at 27C and 37C. On the vitelline membrane and in the yolk SE counts decreased at 4C and 8C but increased at 15C, 27C and 37C.

The study showed the importance of storage temperature in prevention of SE growth. Shell eggs for pasteurization should be fresh and stored at low temperatures.

This article discusses issues that determine the way that poultry is produced. Emphasis is given to the success of Salmonella control in the UK.

There was a dramatic reduction in Salmonella Enteritidis in poultry meat and eggs following regulatory activities in the early 1990’s. Vaccination of poultry against Salmonella played an important role in drastically reducing Salmonella contamination of table eggs.

Antibiotic resistance of Salmonella Typhimurium DT104 and the implications for use of anti-microbials in poultry is discussed. The consequence of withdrawing antimicrobial therapy and growth promoters often results in untreated conditions that are detrimental to the welfare of poultry.

Poultry welfare and the need to provide a suitable environment for the birds is also discussed.

The Dutch poultry industry has been rather successful in the battle against Salmonella typhimurium and enteritidis. The reduction in the incidence of infected flocks is remarkable. Unfortunately a new Salmonella strain has taken over the role and is now challenging the industry..

Salmonellosis is a serious illness transmitted by various serotypes of Salmonella that are present as contaminants in chicken carcasses, eggs, and egg products. In a review, Bäumler and colleagues suggest that the increased incidence of food-borne Salmonella since the late 1960s is due to the emergence of one particular serotype, S. Enteritidis, as a major poultry-associated pathogen. Through retrospective analysis of epidemiological data on the prevalence of Salmonella in humans and poultry, the authors propose that the culling of poultry infected with two related Salmonella serotypes (that carry a common antigen, O9) depleted flock immunity, enabling S. Enteritidis to fill the niche left by the elimination of the avian pathogens.

Samples collected from wild animals shot during hunting were examined for verocytotoxin-producing Eschericia coli (VTEC 0157) and thermophilic Campylobacter and Salmonella spp. VTEC 0157 was only isolated from 1 wild boar. Salmonella species were only isolated from gulls. Thermophillic Campylobacter species were commonly isolated from all species except deer.