The cost of providing animal feed to livestock and poultry accounts for 60-70 percent of the total outlay of running a livestock or poultry business. Reducing this expense has been the goal for generations of farmers. Use of enzymes in animal feed make this goal a reality, and modern farmers have achieved phenomenal gains in the efficient and economical production of livestock. The use of enzymes in farm animal nutrition has been an important part of achieving this success while maximizing the health of the animals and minimizing the impact on the environment.

This journal provides insight as to why Bacillus subtilis is such a remarkably diverse bacterial species – capable of growth within diverse environments including the gastrointestinal tracts of animals. Though dated, the article shows that this highly diverse bacteria has always been widely used for animal husbandry and other applications.