Gaffky is credited with being the first to culture the causative agent of typhoid (S. typhi) in 1884. At that time, it was also known that bacteria similar to S. typhi could cause enteric disease in humans and farm animals. This was confirmed when Salmon and Smith reported the isolation of the bacteria responsible for 'hog cholera' or 'swine fever' in 1885. The name Salmonella was subsequently adopted in honour of Salmon, an American veterinary surgeon. In the early to mid-20th century, there were many pioneering studies into the identification and differentiation of Salmonella. The schemes that were developed made use of the fact that, although Salmonella show considerable antigenic diversity, they elicit two principal antibody reactions in infected animals. Thus antibodies are produced against cell-surface or somatic O antigens and flagella or H antigens. In 1929, White developed a typing scheme based on this antigenic variation, which was later modified by Kauffmann. This work enabled the differentiation of Salmonella into serovars. In the UK, as in many other countries, it is usual to supplement this with phage typing. With common serovars or phage types (PTs), it may be necessary to take identification further and include a range of molecular or genotypic typing methods

1. Animal welfare 6313
2. Birds 937
3. Dairy cows 470
4. food poisoning 2
5. Health 527
6. Meat products 4
7. milk products 6
8. Public health 151