Over the years several letters and articles in The Scientist have expressed concern about the use of antibiotics in domestic animal production and the potential for selection of antibiotic-resistant bacteria. Recently, an American Academy of Microbiology report called for efforts to develop new agricultural methods that reduce dependence on antibiotics, such as the use of competitive exclusion bacteria in poultry to combat the Salmonella problem.1 While the competitive exclusion approach in poultry and other livestock has received considerable interest and funding in recent years, it should be noted that other approaches are also being investigated in ruminant animals (i.e., beef and dairy cattle).
One focus of my laboratory for the past 15 years has been to examine alternatives to antibiotics for ruminant animals. Under some dietary conditions, lactate can accumulate in the rumen and decrease ruminal pH. Because the animals do not feel well (i.e., acid indigestion), they eat less ...
