PAN Livestock Services Ltd Director, Dr James Hanks, and Livestock Information Analyst, Dr Emma Taylor-Holt, presented research at the British Cattle Veterinary Association (BCVA) Congress 2024 at Celtic Manor in Newport, Wales on 17^th October 2024.

The National Johne’s Disease (JD) Tracker Database, which was established in Autumn 2023, is the result of a collaboration between Dairy UK, PAN Livestock Services Ltd, National Milk Records (NMR) and Cattle Information Service (CIS). The National JD Tracker Database is an anonymised InterHerd+ database containing milk recording and milk ELISA data for herds which test on a quarterly basis. From 2015 to 2023, median values for all JD Tracker parameters improved, including the milk ELISA average test value (ATV), which decreased by 43% from 9.7 to 5.7, and within-herd prevalence (based on a cut-off of 30), which reduced by 64% from 5.5% to 2.0%.

Milk ELISA positive cows are not equally distributed amongst the herds. According to 2022 data, when herds are ranked by ATV, quartile 4 herds (the ‘worst’ 25% of herds) contain 53.9%, 63.5% and 71.3% of milk ELISA tests >30, >60 and >100, respectively. These ATV quartile 4 herds also contain 50.6%, 56.6% and 64.7% of J4, J5 and priority cull cows. Based on a herd size of 226 cows, ATV quartile 4 herds contain 8.9 times more JD positive cows, 9.1 times more J5 cows and 13.2 times more priority cull cows compared to ATV quartile 1 herds. Future research could use milk ELISA data, risk assessments and qualitative methods to compare the management of JD in ATV quartile 1 herds (the ‘best’ 25% of herds) and ATV quartile 4 herds (the ‘worst’ 25% of herds).

To access the BCVA conference proceedings, please click HERE.

To access our recently published peer-reviewed paper on Johne's Disease trends, please click HERE.