Bacterial contamination in feed ingredients, formulated chicken feed and reduction of viable bacteria by pelleting.

The number of bacteria in steam-pelleted or crumbled chicken food was compared with the number in individual ingredients and in mash. A few bacteria were detected in white-fish meal processed Alaska pollack. Highest yields were from alfalfa meal. Colonies numbering 3.5 x 10(3)-4.2 x 10(5) were obtained by heart-infusion agar culture, and 2.1 x 10(2)-7.0 x 10(4) with deoxycholate hydrogen sulphide lactose agar, from 1 g mash. After pelleting or crumbling the number of colonies in 1 g was reduced to 0-1.9 x 10(3) and 0-3.0 x 10(0) respectively. Bacteria in the lactose medium, mostly coliform, were observed in only 1 of 18 samples.