M.N. SKOV, B. CARSTENSEN, N. TORNO šE AN D M . MA DS E N. 1999. The present study compares four different sampling methods potentially applicable to detection of Salmonella in broiler flocks, based on collection of faecal samples (i) by hand, 300 fresh faecal samples (ii) absorbed on five sheets of paper (iii) absorbed on five pairs of socks (elastic cotton tubes pulled over the boots and termed 'socks') and (iv) by using only one pair of socks. Twenty-three broiler flocks were included in the investigation and 18 of these were found to be positive by at least one method. Seven serotypes of Salmonella with different patterns of transmission (mainly horizontal or vertical) were found in the investigation. The results showed that the sock method (five pairs of socks) had a sensitivity comparable with the hand collection method (60 pools of five faecal samples); the paper collection method was inferior, as was the use of only one pair of socks. Estimation of the effective pool sizes for the different methods was also carried out.

Eight different serotypes of Erysipelothrix rhusiopathiae were isolated from 39 outbreaks of erysipelas in poultry, serotypes 1, 5, 6 and 9 being most prevalent. More than one serotype was demonstrated in five outbreaks. Only White Leghorns were affected as far as erysipelas in chickens is concerned, and 94% of the flocks were kept on sloping wire floors of the Pennsylvania system. No relationship between serotype, host predilection and virulence was observed, nor was there a seasonal distribution. The epidemiological and preventive aspects of the present findings are discussed.