Triaxial accelerometers for recording grazing and ruminating time in dairy cows: An alternative to visual observations
Triaxial accelerometers for recording grazing and ruminating time in dairy cows: An alternative to visual observations
Date
2017
Authors
Adolfo Armando Rayas-Amor, 0000-0002-5958-8721
ERNESTO MORALES_ALMARAZ, 0000-0003-0675-2193
RODOLFO VIEYRA-ALBERTO, 0000-0001-5889-1203
ANASTACIO GARCÍA MARTÍNEZ, 0000-0001-8021-5412
Carlos Galdino Martinez-Garcia, 0000-0001-9924-3376
Rosy Cruz-Monterrosa, 0000-0003-2859-013X
Genaro Miranda-de la Lama, 0000-0002-6848-1010
Journal Title
Journal ISSN
Volume Title
Publisher
Elsevier
Australian Veterinary Behaviour Interest Group: a special interest group of the Australian Veterinary Association
International Working Dog Breeding Association
Australian Veterinary Behaviour Interest Group: a special interest group of the Australian Veterinary Association
International Working Dog Breeding Association
Abstract
Description
he aim of this study was to validate the recordings of a commercial triaxial accelerometer (HOBO Pendant G data loggers) with respect to visual observations of grazing and ruminating time of dairy cows. Seven lactating Holstein cows with a mean body weight of 602 ± 45 kg were used for the study. Grazing and ruminating times were recorded using HOBO loggers (31.5 hours of total observations for grazing and ruminating) that were attached to the lateral-medial side of the jaw using a strap attached to the head of each cow in a position such that the X-axis was parallel to the ground, the Y-axis was perpendicular to the ground pointing upward, and the Z-axis was parallel to the ground pointing away from the sagittal plane; these relative positions were defined when the cow was in a natural head-up position. Median acceleration (m/s2) readings in the X-axis >0.175 and <0.95 indicated grazing activity, whereas readings in the Z-axis >-0.275 and <0.0875 indicated ruminating activity. The degree of vertical tilt (° Y-axis) was used to determine grazing position (readings >0° and <61°) and ruminating (readings >0° and <25.8°). Results showed a significant (P < 0.001) relationship of estimated grazing time against visual observations when acceleration (X-axis) was used only; nonetheless acceleration (Z-axis) was not significant (P > 0.05) for estimating ruminating time. When acceleration and tilt were used for estimating grazing (X- and Y-axis) and ruminating (Z- and Y-axis) time, the slope in both showed a significant (P < 0.001) relationship. The prediction R2 in both activities indicated that acceleration (X- and Z-axis) and tilt (Y-axis) of HOBO loggers explained 0.961 and 0.945 of the variance in visual observations per cow/day. Therefore, the validation of the HOBO loggers was successful on a per cow/day and per day basis.
Keywords
CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA