ARMIES of pathogenic bacteria are toughened up in a mini “boot camp” when they are engulfed by protozoans in the guts of their bovine hosts.
The conventional view was that single-celled protozoans living in the guts of ruminants were benign, supplying the beasts with nutrients by digesting plant matter and bacteria before being digested themselves. Now a team at the National Animal Disease Center in Ames, Iowa, has revealed protozoans’ darker side.
The researchers collected protozoans from the stomachs of cattle and mixed them with a strain of salmonella that fends off digestion by protozoans. Calves fed salmonella that had…
