The use of ultrasound for assessment of muscle area and depth in postmortem preweaned Holstein dairy calves

Abstract

Real-time ultrasound is a noninvasive, quantifiable method of measuring body composition in livestock. Ultrasound has not been used to document changes in body composition in preweaned calves. The prewean growth period is a critical stage of calf development. An assessment of growth may include weighing of calves or postmortem evaluation of fat deposits in the perirenal area and coronary groove. None of these parameters offer real-time information, and an antemortem evaluation of body condition is needed. The purpose of this study was to validate the use of ultrasound for the measurement of the longissimus dorsi muscle (ribeye) linear depth and the external carpi radialis (front) and the semitendinosus (hind) muscle area in postmortem preweaned Holstein calves. Our objective was to determine the relationship between the carcass and ultrasound measurements for the ribeye depth and the front and hind muscle area. If validated, ultrasound may be used antemortemly in future scientific studies to assess muscle deposition in preweaned calves.