Salmonella infection in horses in England and Wales, 1973 to 1979.

This research outlines the observations and trends in Salmonella infections in horses throughout the years 1973 to 1979 in England and Wales. The study also investigates drug resistance patterns in the Salmonella strains causing these infections.

Incidents of Equine Salmonellosis

• The period from 1973 to 1979 saw fluctuations in the number of salmonellosis incidents in horses. From a total of 23 infections reported in 1973, this increased to 111 cases in 1976, marking the peak of such incidents during the period under study. However, the number of incidents again fell to 32 by 1979.
• Out of the 416 incidents identified throughout the seven-year period, Salmonella typhimurium caused 292, while 33 different serotypes caused 121 instances. In three cases, rough strains of salmonella were implicated.

Salmonella Serotypes Involved

• The study found a rise in the number of incidents caused by serotypes other than Salmonella typhimurium. There was only one such case in 1973, but this figure grew to 32 by 1976.
• There was also an increase in the variety of salmonella serotypes involved in these infections. In 1973, two different serotypes were identified, a number that spiked to 23 by 1977. However, a downward trend was observed after this peak.

Drug Resistance of Salmonella Strains

• Drug resistance monitoring was carried out on the bacterial strains from horses. The results showed resistance to streptomycin and sulphonamides in most of the Salmonella strains.
• Resistance to other antibacterial drugs was low overall. A total of 17 different antibiotic resistance patterns were identified, but it was uncommon for the strains to exhibit resistance to more than two antibiotics.