title: Minimized Bolus-Type Wireless Sensor Node with a Built-In Three-Axis Acceleration Meter for Monitoring a Cow's Rumen Conditions.
abstract: Monitoring rumen conditions in cows is important because a dysfunctional rumen system may cause death. Sub-acute ruminal acidosis (SARA) is a typical disease in cows, and is characterized by repeated periods of low ruminal pH. SARA is regarded as a trigger for rumen atony, rumenitis, and abomasal displacement, which may cause death. In previous studies, rumen conditions were evaluated by wireless sensor nodes with pH measurement capability. The primary advantage of the pH sensor is its ability to continuously measure ruminal pH. However, these sensor nodes have short lifetimes since they are limited by the finite volume of the internal liquid of the reference electrode. Mimicking rumen atony, we attempt to evaluate the rumen condition using wireless sensor nodes with three-axis accelerometers. The theoretical life span of such sensor nodes depends mainly on the transmission frequency of acceleration data and the size of the battery, and the proposed sensor nodes are 30.0 mm in diameter and 70.0 mm in length and have a life span of over 600 days. Using the sensor nodes, we compare the rumen motility of the force transducer measurement with the three-axis accelerometer data. As a result, we can detect discriminative movement of rumen atony.
authors.affiliation: Faculty of Engineering, Kyushu University, Fukuoka 819-0395, Japan. nogami.hirofumi.406@m.kyushu-u.ac.jp.|Research Center for Ubiquitous MEMS and Micro Engineering (UMEMSME), Advanced Industrial Science and Technology (AIST), Tukuba 305-8564, Japan. nogami.hirofumi.406@m.kyushu-u.ac.jp.
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Nogami
authors.affiliation: National Institute of Animal Health, National Agriculture and Food Research Organization (NARO), Tukuba 305-0856, Japan. sarai@affrc.go.jp.
authors.forename: Shozo
authors.initials: S
authors.lastname: Arai
authors.affiliation: Research Center for Ubiquitous MEMS and Micro Engineering (UMEMSME), Advanced Industrial Science and Technology (AIST), Tukuba 305-8564, Japan. hironao.okada@aist.go.jp.
authors.forename: Hironao
authors.initials: H
authors.lastname: Okada
authors.affiliation: Research Center for Ubiquitous MEMS and Micro Engineering (UMEMSME), Advanced Industrial Science and Technology (AIST), Tukuba 305-8564, Japan. chou-ran@aist.go.jp.
authors.forename: Lan
authors.initials: L
authors.lastname: Zhan
authors.affiliation: Research Center for Ubiquitous MEMS and Micro Engineering (UMEMSME), Advanced Industrial Science and Technology (AIST), Tukuba 305-8564, Japan. toshihiro-itoh@aist.go.jp.|Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa 277-8563, Japan. toshihiro-itoh@aist.go.jp.
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Itoh
mesh_terms: D000138:Acidosis; D000818:Animals; D002417:Cattle; D002418:Cattle Diseases; D004032:Diet; D005260:Female; D006863:Hydrogen-Ion Concentration; D007774:Lactation; D012417:Rumen
keywords: animal health monitoring system; bolus type wireless sensor node; rumen monitoring