Effect of Various Dietaries on the Anatomical Development of the Stomach in the Calf

Abstract
Twenty-seven newborn calves were allotted to 3 major dietary groups: milk (Group A); milk, hay, and grain (Group B); milk plus various substances administered into the rumen (Group C). Except when sacrificed earlier, calves received colostrum ad libitum from their respective dams for 3 days following birth. In Group A, 3 calves were sacrificed at one day of age, one at 3 days, two at 4 wk, two at 8 wk, and two at 12 wk. In Group B, 3 calves were sacrificed at 4 wk, two at 8 wk, and two at 12 wk. All calves in Group C were sacrificed at 8 wk. After sacrifice, each calf was subjected to systematic dissection of the abdominal region. The size and position of various organs in the abdominal cavity of calves fed milk only and milk plus the experimental dietary supplements were compared to those of calves fed a normal diet of milk, hay, and starter. Papillary growth in the rumen was stimulated by the administration of at least 43 m of C3 or C4 volatile fatty acids. Administration of milk into the rumen also stimulated papillary growth. The introduction of plastic sponges into the reticulo-rumen promoted an increase in capacity and muscular development. Feeding hay and starter in addition to milk resulted in forestomach development which included papillary and muscular growth of the reticulo-rumen and pigment deposition in the rumen muscosa. Histological observations suggest that the origin of this pigment probably is the rumen contents in animals fed hay and grain. Extensive papillary development was observed in rumens of zero- to three-day-old calves. Older milk-fed calves showed less development; thus early post-natal regression is suggested.