Johne's is a wasting disease which initially presents no signs, passing unnoticed in the farm system until its latter stages - by which time, it has already spread to other animals in the herd.
Through DairyNZ, New Zealand dairy farmers contribute $500,000 to the Johne's Disease Research Consortium (JDRC) established two years ago to develop practical tools to ensure Johne's is not a threat to New Zealand's agricultural economy or trade. Meat & Wool, AgResearch, DeeResearch, FRST, Massey University, LIC and University of Otago are also involved in the research which has a total spend of $9.5 million over five years.
DairyNZ chief scientist, Professor Eric Hillerton, is one of eight consortium directors. He says the research will provide quicker identification of infected animals and improved disease management for better animal health, along with more efficient production.
Initial results of the research, which began in 2008, show that 20 percent of New Zealand dairy farms have cases of Johne's disease on their properties in the last three years. Of those, 2 percent are suspected cases, while 18 percent are confirmed.
The JDRC research will provide a greater understanding of the disease and its importance to the New Zealand dairy industry - how to detect Johne's and develop a strategy to manage it.
Johne's disease results from an infection common in ruminant animals (cattle, deer, sheep, goats and wildlife) caused by a bacterium called Mycobacterium avium subspecies paratuberculosis (MAP).
Animals are usually infected shortly after birth but do not present signs until much later, when wasting and diarrhoea leads to emaciation. Often, cattle are culled before this stage. It affects the intestine, it has no signs until it becomes more acute with age and animals become thin and don't produce.
Will we be Johne's-free?
We probably will not eradicate Johne's, because the bacteria are found in wildlife species and survives in soil, so rather than eradicating the disease, it becomes a control issue. The disease exists here and we need to know about it and what its impact might be.
JDRC research has four key focus areas - improved diagnosis; understanding the biology of the disease; finding a gene-marker for resistance to Johne's; and a herd management programme to identify cost-effective procedures to reduce production losses.
We need a reliable diagnosis tool because what we have at present is not sufficient - the tests are similar to TB tests and can confuse, are slow and somewhat unreliable.
The research is underway through Massey University, LIC, AgResearch and Otago University.