USING EXAMINATIONS OF YOUNG BLACK-HEADED GULLS (LARUS-RIDIBUNDUS) FOR THE DETECTION OF SALMONELLAE IN THE ENVIRONMENT

During June 1991, cloacal smears from nestlings and chicks of black-headed gull (Larus ridibundus) of the nesting colonies in the middle reservoir of the water system Nove Mlyny (Breclav district) were examined for the presence of salmonellae. On 13 June 1991, 96 yo ng gulls were examined and Salmonellae were found in 20 gulls (i. e. 20.83 %), the serotypes being Salmonella typhimurium and S. derby. On 25 June 1991, 171 juvenile gulls were examined and salmonellae were found in 63, i. e. 36.84 % (S. typhimurium, S. enteritidis, S. agona, S. montevideo, S. derby, S. hadar, S. infantis and S. abony. On 16 May 1991, 79 eggs of black-headed gulls from the same colony were examined and no salmonellae were found. It was proved that the water flowing into the reservoir from the river Jihlava and river Svratka in June 1991 was contaminated with salmonellae (i. e. S. typhimurium, S. montevideo). Examinations of the juvenile black-headed gulls can be used for the detection of the occurrence of salmonellae in the water.