The goal of this study was to investigate the feasibility of ultrasonographic assessment of reticuloruminal motility in 45 healthy cows. The transducers of five ultrasound machines were connected to a digital video recorder and placed simultaneously at five sites on the left side of the cows to scan the reticulorumen (reticulum; ruminal atrium; dorsal sac of the rumen; left longitudinal groove; ruminal recess, caudodorsal and caudoventral blind sacs). The video streams from all five ultrasound machines were recorded synchronously with the same time line and displayed on a single monitor. Time 0 was defined as the start of a biphasic reticular contraction. The reticulum was visualised in all cows and had 11.0 ± 2.12 biphasic contractions in 9 min. The ruminal atrium was visualised in 40 (89%) cows and had 10.7 ± 2.10 contractions in 9 min, which started at the time point 5.0 ± 0.83 sec and lasted 7.0 ± 2.14 sec. Contractions of the dorsal sac of the rumen, visible in all cows, were visualised in 29 (64%) cows. There were 9.5 ± 1.8 contractions in 9 min that started at the time point 4.0 ± 0.85 sec and lasted 8.2 ± 1.04 sec. The left longitudinal groove was seen contracting in 39 (87%) cows. There were 10.2 ± 1.98 contractions in 9 min that started at the time point 4.1 ± 1.81 sec and lasted 7.8 ± 1.19 sec. Contractions of the ventral sac of the rumen (ruminal recess) were seen in 31 (69%) cows. There were 7.5 ± 2.59 contractions in 9 min that started at the time point 14.3 ± 4.30 sec. Contractions of the caudodorsal and caudoventral blind sacs were seen in 34 (76%) cows. There were 9.0 ± 2.75 (1.0 ± 0.31) contractions/min and 9.4 ± 2.09 (1.0 ± 0.23) contractions/min of the dorsal and ventral blind sacs, and they started at the time points 6.2 ± 1.32 sec and 21.3 ± 6.20 sec, respectively. Primary contraction cycles were seen in all cows and secondary cycles in 22 (49%) cows. The former were complete in 37 (82%) cows and incomplete in 8 (18%). There were 11.0 ± 2.12 primary and 4.5 ± 2.15 secondary cycles in 9 min, and the ratio between primary and secondary cycles averaged 2.4:1. Ultrasonography is suitable for the assessment of reticuloruminal motility
Animals Cattle