Salmonella and the market dairy cow: Transport contamination – risk for farm biosecurity

Floors of trucks or trailers were sampled for Salmonella before culled dairy cows were loaded from cooperating farms and auction markets in New York (East) and California (West) prior to transport to slaughter establishments. Sampling occurred during two periods, winter and summer. These vehicles were sampled again after cattle were unloaded at slaughter establishments. Four of six vehicles picking up cattle from dairy farms were positive for Salmonella spp. before cattle were loaded at East locations during winter, while five of seven were positive during the summer. One of five vehicles picking up cattle from auction markets was positive for Salmonella spp. at an East location during winter, while all four sampled during the summer period were positive. During winter at the West location all trucks or trailers were positive for Salmonella . During the summer sampling, nine of 13 vehicles that arrived at dairy farms and four of six that arrived at auction markets to pick up cattle were positive for Salmonella before cattle were loaded. Biosecurity procedures need to address the risk of Salmonella contamination from cattle transport.