Determination of backfat thickness with transrectal ultrasonography in cattle

Abstract

The purpose of this study is to determine the Body Condition Score (BCS), which is subjectively measured in dairy cattle with inspection and palpation of backfat thickness, objectively by using transrectal ultrasonography examination method after delivery. Fortyfour cows, randomly selected from 350 dairy cattle with average 650 kg live weight and 2 -6 lactation number have been used. Cows have been separated in two groups according to BCS; which are: Group 1 (BCS ≤ 3) 22 cows ("V" shape observed upon lateral view of pelvis, BCS equal to or below 3) and Group 2 (BCS ˃ 3) 22 cows ("U" shape observed upon lateral view of pelvis, BCS above 3). Subcutaneous fat thickness have been determined by examining body thickness using ultrasonographic imaging above the skin. In this study, ultrasonographic images were obtained by transrectal ultrasound examination method for the first time, and backfat thickness was determined and presented for literature. In the transrectal ultrasound examination; A hand-held probe was inserted from the rectum after rectum is cleared, it was pushed forward inside the cavum pelvis, and measurements were performed on the fat tissue between the muscle and skin layers by scanning vertically using the probe on the sacral region between the upper parts of last lumbar vertebrae, sacrum and tuber coxae. Corresponding images resulting from the examination were saved on the ultrasonography device, and evaluated after being transferred in software. In result of this study, backfat thickness of BCS ≤ 3 and BCS ˃ 3 groups were determined according to ultrasonography examination method, and a difference was observed between groups (p<0,05). TMR (Total Mixed Ration) analysis had been done. In this study 305-day milk yields have been determined and no difference has been determined between groups (p˃0,05).