by George Looby, DVM
The January issue of Consumers Report featured an article summarizing the findings of a group of investigators from the magazine who conducted a representative sampling of pork products from several sources to determine their level of bacterial contamination. It is recognized that while the animal is alive, most edible parts are sterile but during and after slaughter the potential for contamination rises significantly. Today’s packing house environment is far superior to that which existed years ago but the potential for contamination still exists with the need for speed on the processing line sometimes compromising good sanitation despite.
The flora of the intestinal tract is most common source of accidental contamination. The gut of all animals — as well as man — contains a virtual garden of bacteria and other microbes both good and bad.
One of the organisms found in 59 percent of the samples collected by Consumers Report investigators was Yersinia enterocoitica which can cause gastrointestinal symptoms in humans and is especially severe in children. Even though it can cause some very unpleasant symptoms it is necessary for very large numbers of a certain serotype of that organism be present in order for it to cause symptoms. Cathy Cochran, a spokesperson for the USDA Food Service and Inspection, stated that the current testing methods do not differentiate between those strains of the organism that cause disease and those that do not. Since 2005 there have been just two reported Yersinia outbreaks in the country, one in pasteurized milk and the other in raw pork chops. Proper cooking would have prevented the problem with the pork chops. Cautionary statements about the proper cooking of pork products go back to biblical times and when first advocated by public health officials, it was to kill trichinosis, which was common in garbage fed hogs. Dr. H. Scott Hurd, former USDA Deputy Undersecretary for Food Safety and now veterinary epidemiologist at Iowa State stated that the organism is fairly common in raw pork and the concern about the organism is low enough that the USDA does not test for it. The consumer should be aware that most of the unprocessed products they consume on a daily basis are not sterile. Proper handling, preparation and cooking is very important in insuring that when it is placed on the table it is safe as possible for consumption.
Another additive of concern noted in the Consumer Report article was a drug called ractopamine which is added to the ration of pigs to promote a leaner carcass. It was originally developed for the treatment of asthma in humans. Consumers prefer a lean cut when purchasing almost any piece of meat and that demand has been met in some measure with the addition of ractopamine to the diets of a variety of meat producing animals and birds. Meeting that demand has not been without controversy. Consumers do not want unknown additives in the products they consume. The FDA has set a limit of 50 parts per billion (ppb) in muscle tissue and the survey conducted by Consumers Report found that in those 240 samples they tested, 20 percent had detectable levels of the drug. However, Dr. Hurd estimates that an adult would have to eat about 700 pounds of raw pork daily for years to have a noticeable effect from the drug.
The question of antibiotics fed to food-producing animals has gone unresolved for many years without a final, definitive resolution to the problem. Consumers have strong concerns about the presence of antibiotics in the food they eat both from the presence of an adulterant in their hamburgers but even more about the development of superbugs that are resistant to a growing number of commonly used antibiotics. Producers on the other hand have found that adding appropriate antibiotics to the rations of their meat-producing animals acts as a growth stimulant, increases feed efficiency and reduces the incidence of subclinical disease in the herd or flock. It is projected that over the next 50 years the demand for food worldwide will increase by 100 percent. If these predictions are correct, the pressure on agriculture to meet this demand will mean that all available resources will have to be brought into play. This may mean that some as yet to be developed technologies must be developed.
This spring the FDA is holding a series of meetings so the public be given the opportunity to provide their input on problems that will be facing livestock producers and veterinarians arising from the agencies move to require veterinary oversight of the therapeutic use of certain medically important antimicrobials. Comments also may be made to the FDA Docket No. FDA-2012-N-1046 at any time.
The FDA has worked with the USDA and other groups to develop a plan it believes will be successful in reducing antibiotic resistance while at the same time avoiding adverse effects on animal health and the animal agricultural industry as a whole. The FDA has laid the groundwork for such changes by preparing three references that help explain the proposed changes. First is a guideline entitled “Judicious Use of Medically Important Antimicrobials in Food-Producing Animals.” This publication lays the groundwork for the phasing out of production uses of antimicrobials important in treating humans. This would include using these products for growth stimulation and increasing feed efficiency in livestock and poultry. Further provisions would be made to insure there was veterinary oversight of those medications used for therapeutic purposes. The second guideline is designed to assist pharmaceutical companies in making the necessary voluntary labeling changes to remove production use and insure that veterinary oversight was necessary for those used for therapeutic purposes. A third draft proposal is designed to improve the efficiency of existing Veterinary Feed Directive (VFD) requirements. VFD drugs are new animal drugs intended for use in or on animal feed which are limited to use under the professional supervision of a licensed veterinarian.
In a nutshell what this means is that once these proposed changes go into effect, a producer will no longer be able to buy medicated feed or animal drugs directly from a supplier unless the producer has a valid prescription or order from a licensed veterinarian. The impact of these proposals is obviously yet to be seen. Everyone involved in the production chain will feel some impact and as to how it will play out is a long way from resolution.