Associations between sensor based behavioural parameters and transition disease in dairy cows

Abstract

The objective of this single cohort observational study was to analyse and determine the predominant periparturient associations of behaviour during the transition period and the onset of hypocalcemia and ketosis in dairy cows based on sensor data and blood tests. For this study data of 490 mainly Holstein Friesian cows from 8 commercial dairy farms in The Netherlands was used. The cows were all equipped with a neck and a leg sensor, attached to the neck collar and one front leg respectively, to measure the following behaviour variables: minutes of eating, -ruminating, -inactivity, -lying and the leg activity (number of steps) per cow per day. The farms were visited weekly and blood samples were taken to determine the calcium concentration (<48h postpartum) and BHBA concentration in the first week (6±3 days in milk) and second week (13±3 days in milk) of lactation. Generalised linear models with a stepwise backward procedure was used to analyse the datasets. Based on this study multiple associations were found. First of all, the average eating, ruminating and inactive time in de three weeks and last two days antepartum had a strong negative association with the calcium concentration. The first two days postpartum the calcium concentration was associated with all behavioural variables. The negative association between de calcium concentration and BHBA concentration, indicates a higher risk of developing ketosis after (sub)clinical hypocalcemia. On average the BHBA concentration in the first week postpartum was 0.034 higher for each 0.1 mmol decline of calcium concentration. For the BHBA concentration in the second week postpartum this is 0.045 higher for each 0.1 mmol decline of calcium. The negative association between the highest measured BHBA concentration within the first two weeks postpartum and the calcium concentration was a rise of 0.047 BHBA for each 0.1 mmol decline of calcium concentration. Average lying time in 6-3 weeks antepartum and 2 days antepartum and the standard deviation in the two days postpartum show a strong association with BHBA concentrations two weeks postpartum. The analysis of the behavioural variables postpartum showed significantly that the behaviour postpartum was associated with antepartum. All of the behavioural variables are associated with BHBA levels in the first week. We can conclude that behavioural sensor data output during the dry period as early as 6 weeks antepartum is associated with the calcium- and BHBA concentrations postpartum.