Concentrations of Fecal Volatile Fatty Acid and Lactic Acid in Neonatal Foals

Abstract

To clarify intestinal fermentation in newborn foals, fecal pH, volatile fatty acid (VFA), and lacticacid were analyzed in 113 fecal samples from 40 nursing neonates between birth and 7 weeks of age. Average values were fecal pH-7.52, VFA-0.26%, and lactic acid-0.01%(fresh basis). Mean molar ratioswere as follows: acetic acid 64%, propionic acid 21%, and butyric acid 15%. Large individual differences were observed in fecal pH, lactic acid, and VFA levels and ratios. Though fetal feces on birth day contained less VFA, fecal-VFA levels tended to rise thereafter, with maximum concentration occurring from 1 day to 1 week of age. Extremely high concentrations of lactic acid occurred in some fecalsamples on 0 and 1 day and 1 week of age. After declining at 1 week of age, fecal pH then tended to increase. It was concluded that it is possible for gut fermentation to produce VFA in neonatal foalsimmediately after colostrum feeding.