Fermentation of [14C]lactose in broiler chicks by cecal anaerobes

Volatile fatty acids and lactic acid were products of [14C]lactose metabolism in 10-day-old broiler chicks. The [14C]lactose and unlabeled lactose were given to chicks in combination with cultures of cecal anaerobes (direct fed microbials) from adult broiler chickens. Aliquots of these cecal anaerobes had been used previously to reduce Salmonella typhimurium colonization in broiler chicks. In the current study, chicks were treated with anaerobes and anaerobes plus lactose on the day of hatch. Chicks given lactose plus anaerobes also received unlabeled lactose in the drinking water. Chicks in all treatment groups received [14C]lactose on Day 10 posthatch. After 5 h, most of the radiolabel was detected in the foregut and intestine. Significantly lower concentrations of [14C]lactic acid were detected in the serum and foregut of chicks given anaerobes and anaerobes plus lactose than in the similar samples from control chicks. Additionally, significantly less [14C]lactic acid was detected in the feces of chicks treated with anaerobes plus lactose than in feces from control chicks and chicks receiving only anaerobes. Significant differences in the total content of volatile fatty acids and lactic acid were detected in the serum, liver, intestine, and ceca of chicks treated with anaerobes or anaerobes plus lactose. These data indicate that cecal flora utilize lactose to produce volatile fatty acids and lactic acid.