Temperature Change Within the Rumen, Crop Area, and Rectal Area when Liquid of Various Temperatures Was Fed to Calves

Temperatures in the rumen, crop area, and rectal area of calves were recorded with a radio telemetry system.Mixtures of milk and water at 8, 17, and 37 C were fed.Temporal patterns of the post-feeding body temperatures are presented.The transient effects on body temperature resulting from the liquid intake were a function of the temperature and quantity of liquid ingested.Often when the body temperatures returned to their prefeeding values a positive temperature gradient with body depth was noted.The post-feeding temperature drop was the most prominent feature of the temperature responses.After ingesting 2.7 kg of liquid at 17 C the average decrease in rumen temperature was 7.2 C.