K. Donat and colleagues reported on the successful control and likely eradication of MAP from a 450-cow commercial dairy herd in Germany. This case study, lasting a decade (2012-2022), was published in the Open Access journal Animals March 21, 2024.
The above graph was generated from the study data provided in Table 1 of the publication (red bars) with the addition of a logarithmic regression line (dotted black line). The herd had a high infection rate in 2012 with 17.83% of cows being fecal culture-positive and from 2020 to 2022 the herd had zero culture-positive cows.
ABSTRACT
This longitudinal case study provides an in-detail report of the process towards the elimination of Mycobacterium avium subsp. paratuberculosis (MAP) from a closed 450-head commercial dairy herd. In parallel, two diagnostic approaches were applied to all cows in annual intervals during 2012–2022: detection of MAP in individual faecal samples by bacteriological cultivation on solid medium and detection of MAP-specific antibodies by ELISA. For each annual sampling, the kappa coefficients for test agreement and the survival rates of MAP-positive and MAP-negative cows were calculated. Applying a multivariable linear regression model revealed a significantly lower fat-corrected 305-day milk yield for MAP-positive cows. The true prevalence of MAP shedders reduced from 24.2% in 2012 to 0.4% in 2019 and during 2020–2022, no MAP shedder was identified. Test agreement was generally low and bacteriological cultivation showed positive results earlier than the ELISA. In the first years of control, the survival of MAP shedders was longer than in the final stage. In conclusion, the elimination of MAP from a dairy herd might be feasible within a decade. Changes in the test agreement must be considered. Timely removal of MAP shedders, hygienic calf rearing, and colostrum supply are key for successful control.
COMMENTS
This publication is worth reading in detail, especially for dairy producers and veterinarians focused on dairy cattle. The basic principles also apply to other animal species. This case study contains many useful observations. Here is just one example: “….the farmer observed better fitness in multiparous cows and a more pronounced drop in milk of MAP shedders of second and higher parity. This was worth spending EUR 57,963 (US $62,887) on paratuberculosis control during 11 years, which is approximately EUR 11.70 (US $12.69) per cow per year.”
There are several important lessons from this case study and here is my list of important lessons, based both on this publication and others like it:
- Paratuberculosis control takes time and therefore patience.
- Farmer engagement and continuous support is vital for success.
- Veterinary supervision and monitoring are a critical, and often overlooked, part of the program.
- Herd management changes are essential for effective paratuberculosis control.
- Regular herd testing to identify the most infectious cows for segregation at calving time and then culling is necessary.
- Governmental programs with funding to offset the costs of paratuberculosis control help make control programs financially feasible for producers.
- Paratuberculosis eradication can be achieved.