The failure of the oesophageal groove reflex, when fluids are given with an oesophageal feeder to newborn and young calves.

The fate of colostrum and other fluids given with an oesophageal feeder was studied in newborn calves and in young calves up to 3 weeks by means of radiological techniques. Any fluid given with an oesophageal feeder was found in the forestomachs, since it apparently did not induce an oesophageal groove reflex. Also when suckling was induced during feeding with the oesophageal feeder, the oesophageal groove reflex did not occur. The outflow of colostrum and other fluids from the forestomachs to the abomasum and small intestine occurred for the most part within 3 hours. Only the emptying of the ventral ruminal sac was sometimes delayed for 24 or 48 hours. The results obtained in calves up to 3 weeks old did not differ from those obtained in newborn calves. It was concluded that although colostrum given by oesophageal feeder entered the forestomachs, the rapid flow to the abomasum and small intestine created the conditions for a sufficient absorption of immunoglobulins. Application of colostrum with an oesophageal feeder in newborn calves promises to be a timesaving and effective method for creating an optimum passive immunity of the calves.