DAIRY: TRUE CASES & STORIES - JOHNE'S INFORMATION CENTER

Eradication of Johne’s
disease in 12 months!

photo with permission from Dairy Today, May 1997

A Wisconsin farm family purchased a dairy farm in 1983. They bought cows from other farms and begin modernizing the facilities. Herd production steadily climbed until 1990 when both total herd production and production per cow started declining. The rapid eradication program began in July 1995.

Graph illustrating effects of Johne's treatment program In 1993 and 1994 they had some mortalities in bred heifers. Eventually, a diagnosis of Johne’s disease was made in the herd. By that time, it was estimated that over 30% of the adult herd was M. paratuberculosis-infected. The farm family applied for a grant from the Wisconsin Milk Marketing Board to try new diagnostic tests for Johne’s disease in combination with an aggressive Johne’s disease control program to eradicate the infection from their herd. This study was initiated in July 1995 in cooperation with the University of Wisconsin School of Veterinary Medicine.

The objective of the study was to show it is FEASIBLE to eradicate Johne’s disease with existing diagnostic tools and aggressive management. It was not designed to find the most cost-effective method.

Key elements of the rapid eradication program were:

1.	Improved calf management:
	-	prompt removal of calves from cows after birth
	-	feeding ONLY milk replacer to calves after 24 hours of age
	-	new calf rearing facilities using calf hutches
2.	Culling of all heifers less than 2 years old because a high (>80%) M. paratuberculosis infection rate (culture and gamma interferon-positive animals).
3.	Culling of all adult cattle that tested positive to any one of three diagnostic tests used: serum antibody ELISA, fecal culture by the BACTEC method, and gamma-interferon assay.
4.	Replacement of culled adult cattle with cows from a totally test-negative herd (ELISA and gamma-interferon tests). An article based on an interview of farm family was published in Dairy Today, May 1997. The article emphasizes concerns over the inability of conscientious dairy producers to guarantee that heifers that test-positive for Johne’s disease go to slaughter and not into other herds. Download the Dairy Today article.

The details of the rapid eradication project were reported at the 1998 annual meeting of the American Association of Bovine Practitioners.

Download the
6 page manuscript.

Graph illustrating effects on milk production \Milk production did not improve dramatically after elimination of Johne’s disease from the herd in July 1996. This was largely due to the lack of dairy replacements caused by elimination of all heifers from the farm and the fear of bringing Johne’s disease back into the herd by purchase of animals. As a result, the herd became older and animals that would normally have been culled for low production were kept in the herd. Milk production records through the end of year 2000 are shown here. We hope to update this data annually.

Photo of news clipping In desperate need of herd replacements, in the spring of 1998 Pat Kling drove 4 hours to a herd auction in Kiel, WI. They selected this herd sale because it was advertised as being 100% test-negative for BVD and Johne's disease (by ELISA) and so felt fairly safe from re-introduction of the infection to their herd (the newspaper ad for this action is shown here) . Pat bought 4 cows for herd replacements. Pat said that these cattle sold for above normal market value and that in her opinion, "the ELISA results were a major factor". Several other farmers she talked to at the sale agreed. This is an example of how smart buyers can avoid Johne's disease and how smart sellers can profit from having a test-negative herd.

Lessons learned from this on-farm study:

1.	Control programs work: Johne’s disease can be eradicated from dairy herds. It should be noted that on this farm cattle were grazed on pastures during the summer months. Although these same pastures were used prior to the eradication effort, as of February, 2001 there is no evidence of re-infection of the herd grazed on these pastures.
2.	Johne’s disease has a significant impact on milk production.In spite of extensive investigations by the Food Animal Production Medicine group at the University of Wisconsin School of Veterinary Medicine, no other problems were identified on the farm that could account for the declining milk production.
3.	In heavily infected herds the infection pressure can be so great that cattle less than two years old can develop clinical Johne’s disease and die. Any herd that is experiencing clinical Johne’s disease in home-raised heifers before calving, or during their first lactation, likely has a high infection rate in the herd.
4.	Failure to detect Johne’s disease early can lead to high infection rates that become expensive both due to the impact on herd productivity and due to the cost of controling or eliminating the infection.

Epilogue: Photo of one of the Kling's cows.
The Kling family was a little discouraged in 1995 because of all the problems in the herd. Today, however, this farm family is glad to be in the dairy business. Their herd is healthy and productive. They look forward to freshening 13 heifers in the Spring of 2001 and expect this to boost herd production. The Klings continue testing for Johne’s disease annually and plan to join the U.S. Voluntary Johne’s Disease Herd Status Program for cattle. This farm family have become strong supporters of Wisconsin’s efforts to control Johne’s disease.

After reviewing the first version of this story the Klings wanted to stress this point to website visitors:"It is OK to talk about Johne's disease. It is of utmost importance that we talk openly about how to manage and eradicate this disease that can have such a detrimental impact on the dairy industry."