Repeatability of some animal related variables in dairy cows and buffaloes

The aim of this study was to evaluate the repeatability of some animal related variables which could be used in protocols developed for assessing animal welfare at farm level. Recordings were performed in seven dairy farms (four for cattle and three for buffaloes). For each farm 30-40 animals (15-20 primiparous and 15-20 multiparous) at a lactation stage of 100-160 days were selected. Observations were conducted by a team of 8 trained assessors. The animals were observed in three occasions at 3 week intervals. Each animal was always assessed by the same observer. The variables collected for each animal were the following: behaviour during milking (stepping and kicking from the attachment to the removal of cups); avoidance distance (distance between the observer and the point at which the cow moved); lameness (score ranging from 0 - not lame - to 3 - very lame); cleanliness (the pelvis was divided into five areas and rated on a scale with 0: clean and 2: very dirty). For each farm and each variable repeatability was computed using the Kendall coefficient of concordance (W). A ratio between the variance of the animal and the sum of the latter with the error variance was also calculated using a model with one factor (animal), to have a further measure of the precision of observations. These two methods yielded similar results. In particular, in dairy cattle a high repeatability for avoidance distance, stepping and cleanliness was observed, whereas for buffaloes avoidance distance, stepping and kicking were the repeatable variables.