Continuous Computer Acquisition of Feed and Water Intakes, Chewing, Reticular Motility, and Ruminal pH of Cattle
The monitoring of feeding, chewing, and ruminal activity was integrated into one data acquisition system for continuous measurement of 12 dairy cows. Feed mangers were hung from single-point load cells for measurement of feed disappearance from individual stalls. Water flow meters, inserted in supply lines for each stall, generated pulse output for electronic summation of water intake. Jaw movements were detected with a water-filled tube connected to a pressure transducer under the cow's jaw to determine chewing activity. Similar tubes were used to detect contractions in the reticulum. Ruminal pH was monitored continuously with an electrode and pH transmitter. All signals were processed and recorded on a microcomputer using commercially available computer hardware and software. One file was written for each cow monitored. Data were interpreted using algorithms developed with SAS software. Two studies were conducted with 10 lactating cows to evaluate the performance of acquisition hardware, protocols, and interpretation algorithms. Use of only one algorithm to interpret behavior of many cows sacrificed accuracy of bout time borders for some individual cows. Nonetheless, high correlations (r ≥ .85) between computer-interpreted and manually determined variables indicated that performance of the acquisition system was acceptable. With continuous measurement of many cow feeding variables, a more complete understanding of dietary effects on digestive function and performance is possible.