Developmental processes of omasal motility in calves.

Abstract

Developmental processes of omasal motility under normal feeding conditionwere studied. Two male Holstein calves were rumenfistulated at an early age. Intra-luminal pressure changes in the reticulum, and the omasal canal and body were recordedsimultaneously on kymographic paper at regular intervals beginning at 2 or 3 weeks ofage.Cyclic contractions of the omasal canal which coincided with those of the reticulumwere first observed at 4-6 weeks of age. Contractions of the omasal body began to berecognized at 8 weeks of age. When the contraction of the omasal body was first observed, it showed a slow and irregular pattern. With the advance in age, it increased slowly infrequency and became more periodic. Then such a contraction of the omasal body ascould be seen generally between diphasic contractions of the reticulum in adult cattlewas first observed at 29-32 weeks of age.