Development and implementation of a training program to ensure high repeatability of body condition scoring of dairy cows

Abstract

A body condition score (BCS) in dairy cattle is a subjective assessment of the proportion of body fat that she possesses and is a common measure used in animal welfare assessment. The objectives of our study were to develop and implement a training program to produce highly repeatable BCS by many assessors as part of a cross-Canada epidemiological study on dairy cow comfort and welfare. In preliminary studies, we established that without any proper standard operating procedures (SOP) to describe the practical steps of the process and good standard reference for each score, assessors provided with a BCS chart scored with each other only with substantial agreement within 0.5 points and moderate agreement on exact score (mean weighted kappa coefficient=0.79 and 0.46, respectively). Detailed SOP were developed to assess BCS in 4 locations on a dairy farm. Assessing BCS presented more challenges in some locations (when cows exited the milking parlor, when the assessor was located outside the freestall pen) than others (when cows were headlocked at the feed bunk, when assessor was located inside the freestall pen). Additionally, training material and a training procedure were developed to ensure that future assessors would achieve almost perfect repeatability with the trainer within 0.5 points (weighted kappa coefficient >0.80). Twelve trainees followed this training and their repeatability was assessed using photographs in classroom sessions and live observations on farm over a 1-wk period. Repeatability was maintained above target agreement at periodic checks over the 6 mo of on-farm data collection. Two trainers were used as a reference standard to which all trainees were compared. This study demonstrates that to obtain reliable measures, a training program must include validated procedures to help assessors cope with a variety of farm setups. Regular repeatability checks are essential to ensure that the reference standard is maintained over time and to secure high data quality. This method to develop a training program as well as the training program implemented can be used as a model to successfully train on-farm assessors.

Comparison of a classical with a highly formularized body condition scoring system for dairy cattle

“…Such a diagnosis might even not need an accuracy of 0.25 increments, which is however necessary for differentiated body condition curves in normal healthy cows (cf. Vasseur et al, 2013). The weakness of the system for thinner cows may be partly explained by the difficulty to assess the pin bone region correctly.…”

Prevalence of and risk factors for hock and knee injuries on dairy cows in tiestall housing in Canada

“…Body condition score was recorded on a 5-point scale in 0.25 increments (Ferguson et al, 1994), using the procedure described in Vasseur et al (2013).…”

Correlación entre el pH ruminal y el índice de condición corporal en vacas con acidosis ruminal subaguda

“…Given the current and different feeding management conditions hubo una correlación significativa (p<0.01) (r=0.622) entre BCS y pH ruminal, observada en este estudio. Las alteraciones de la BCS podrían estar relacionadas con varias razones, es decir, un nivel adecuado de nutrición y una ración bien diseñada podría afectar el peso corporal de las vacas junto con la conversión de los tejidos para aumentar la productividad (24)(25)(26).…”