Abstract
This study investigated the anatomical and histological characteristics of the abomasum in weaned Holstein calves under two feeding regimens: high-quality alfalfa hay and starter concentrate. The calves were raised under an accelerated feeding system (milk diet provided at 20% of their body weight). This study aimed to determine the effects of diet on the development of the abomasum during the early life stages of calves, which is crucial for digesting both milk and solid feed. Twenty newborn male Holstein calves were randomly assigned to either diet group and monitored from 56 to 60 days of age. Organ weight, abomasal curvature length, and number of abomasal folds were measured. Histological slides were prepared for microscopic examination. No significant differences in anatomical and histological parameters were observed between the two dietary groups, suggesting that both diets provided adequate nutritional support for development. Although the quantity of feed differed, the primary component, milk, remained consistent, contributing to balanced nutrition. This study emphasized the importance of early nutrition in calves and its influence on the anatomical and histological development of the abomasum. However, potential subtle differences warrant further investigation to determine long-term consequences on digestive health and efficiency.