Dealing with B.S.E.
January 01, 1997
by Teresa Acklin
E.U. feed industry discusses problems raised by "mad cow disease."
No single strategy can be adopted by countries in order to protect themselves and control the spread of bovine spongiform encephalopathy, according to feed industry representatives attending the first Worldwide Feed Industry Summit on B.S.E. held in London last year.
Compound feed industry leaders from around the world met in closed session to discuss the ramifications of B.S.E., also know as "mad cow disease," for the industry. They agreed that B.S.E. was no longer just a problem for the United Kingdom, where an outbreak of the disease among herds sparked a public health panic and global bans on British beef, but an international problem that would require every country using rendered materials in livestock rations to formulate and adopt its own safeguards and control procedures.
B.S.E. is a disease of the brain that causes a deterioration of cognitive functions and a loss of motor skills in affected animals. The disease has raised great concern because of the possibility of a link between meat from afflicted animals and Creutz-feld-Jakob Disease, which causes similar symptoms and brain damage in humans.
Although no single, universal answer to the problems raised by B.S.E. surfaced at the summit, held under the auspices of the International Feed Industry Federation, the conference did identify a range of ways to tackle the variety of problems.
"The group agreed that countries can be divided in two where B.S.E. is concerned — those that have it in their national dairy and cattle herds and those that do not," said Roger Gilbert, I.F.I.F. secretary and moderator of the two-day meeting. "Where B.S.E. has been identified in the animal population, everything must be done to eliminate it."
The possibility that B.S.E. can be transmitted by ruminant-to-ruminant feeding has led many countries to ban the use of certain animal protein byproducts in feed. But Mr. Gilbert said simply outlawing rendered products, such as meat and bone meal, blood meal and tallow, from inclusion in animal rations was not a solution.
"Not only are these products a traditional and valuable source of protein and minerals for livestock rations, but in many countries animals are eating only those parts of the carcass that we as humans consume in other countries," he explained. "The issue of cannibalism was discussed. This practice struck a cord with compounders who agreed that while it was not aesthetically appealing, it was considered a totally safe practice until the appearance of B.S.E."
The group learned that the species barrier to B.S.E. transmission is very strong, indicating that non species-to-species feeding of rendered products is safe. However, the dilemma some countries face is how to separate products in the rendering process and to keep them separate throughout the feed processing chain.
"Cross contamination is almost impossible to avoid," Mr. Gilbert said.
The summit participants agreed that in the production of rendered products, "fallen animals" must be treated separately in some circumstances from healthy animal carcasses that have been properly slaughtered.
Ray Bradley, the B.S.E. coordinator at the Central Veterinary Laboratory in the United Kingdom, told delegates that measures taken in the past year greatly had lowered the danger of dairy cows contracting B.S.E. The risk, he said, had "gone from the height of the ceiling in this room to the thickness of the carpet, to the thinness of a piece of paper."
Mr. Bradley also noted the need for the feed and meat processing industries to make sound risk assessments, develop risk management strategies and to communicate these to all involved parties, from clients through to consumers. These plans and strategies are particularly critical as research continues on the causes and effects of B.S.E. and possible links to human illnesses, he said.
"The next 12 months will be an important period in which the progress of this new strain of C.J.D. — if any — may become apparent and results of the research to evaluate any possible connection with B.S.E. will start to come forward," he said.
But Mr. Bradley noted that even if no connections could be proved, preventing transmission of any disease through feed, including scrapie as well as B.S.E., should be an industry objective.
"Much research needs to be done to advise how this can be done effectively while maintaining the nutritional quality of feed containing animal products," he added.
The group also heard from the dean of the medical school at the University College of London, who has been closely associated with the investigation into the strain of C.J.D. in humans thought to be linked to B.S.E. He said there was no conclusive evidence to date, but the incubation period and other similarities suggested a link.
The delegates agreed that even where there is no risk from B.S.E. whatsoever, the public perception issue must be addressed.
"It is not good enough to say a population is now free of the disease," Mr. Gilbert said. "Our customers, and in turn the consumer, must be absolutely confident that the safety issues have been properly resolved and that the risk from eating beef and beef products is no greater than the risks associated with eating other foodstuffs."
The slaughter of all calves imported into the Netherlands from the United Kingdom underscored the importance of public perceptions. In terms of risk, these animals would have produced the safest meat of any bovine animal anywhere, he said.
"However, we cannot expect politicians nor the public to have confidence until the disease has been isolated and rooted out of the national population," he said.
I.F.I.F. President Henk van de Bunt said the summit offered all those involved in compound feed manufacturing an opportunity to learn first-hand about B.S.E.
"(The meeting) helped us in determining what we can and should be doing to ensure our industries take the correct action to maintain the quality of feed products our customers have come to expect from us," Mr. van de Bunt said. "We believe that can be achieved without the unnecessary removal from the food chain of a valuable protein and nutrient source that comes in the form of rendered products."