UBC Theses and Dissertations
Lameness and lying behaviour in grazing dairy cows Thompson, Alexander John
Lameness is a serious welfare issue for dairy cows. To date, the majority of studies have focused on its effect on health and behaviour at the herd-level. The objectives of this study were to identify firstly, between-cow and secondly, within-cow changes in lying behaviour associated with consistent and changing lameness status in grazing dairy cows. Previous studies of lying behaviour in grazing dairy cows have not considered the effect of precipitation, thus a third aim was to determine the effect of precipitation on lying behaviour. A total of 252 dairy cows from 6 pasture-based farms in southern Brazil were gait scored weekly to assess lameness using a 5-point scale (1 – 5, numerical rating score [NRS]) for 4 consecutive wk. Cows were considered to have consistent lameness if they were scored as lame (NRS ≥ 3) on each of the 4 visits and considered to have a changing lameness status if scored as being non-lame (NRS < 3) on at least one of the 4 visits. Cows classified as having a changing lameness status were further classified as developed, recovered, or inconsistent. Lying behaviour was recorded continuously using leg-mounted accelerometers. Cow-level variables included parity, days in milk, and body condition score. Since only one primiparous cow was identified as lame at each of the 4 visits, the between-cow analysis of lameness was run on multiparous cows only. The overall prevalence of clinical lameness on the first visit was 39%, with a development and recovery rate of 16% and 10% over the 4 visits, respectively. The between-cow effect of consistent lameness status on daily lying time and number of lying bouts was dependent on precipitation. There was no within-cow effect of changing lameness status on any of the lying behaviours. Precipitation decreased daily lying time, increased mean lying bout duration, and decreased the daily number of lying bouts. The results of my research provide the first evidence that the effect of consistent lameness status on lying behaviour is dependent on rainfall in grazing dairy cows. Future work measuring lying behaviour of grazing dairy cows should include precipitation as a co-variate.
Item Citations and Data
Attribution-NonCommercial-NoDerivatives 4.0 International