r 1 Association Practitioners; Bovine open ofdistribution. access American Copyright © FOR YOUR INFORMATION L i t A Mold Problem in 1972-73 Feed Grains recognized as a serious problem by various state Gibberella Zeae and federal agencies. Research has been conducted What is it? largely by university personnel. Mycotoxins in Gibberella zeae is a mold (Fusarium roseum) grains should be recognized as emerging diseases found on com and some other field grains. It is a and of growing importance. The cold, wet growing naturally occurring fungus that is a serious problem season of 1972 was ideal for the production of during a wet, cold growing season and harvesting Fusarium mycoses. The delayed harvest contri­ period such as was experienced in 1972. The buted to the problem. Shortage of natural gas greatest problem areas in 1972 seem to be in made it more difficult to dry com. Normally, corn Southern Michigan, Northwestern Ohio, and is dried to 14% moisture. Much of this year’s com Northern Indiana — but reports indicate lesser had moisture levels ranging from 20 to 35%. contamination in a number of other corn- Twenty-three percent moisture has been recog­ producing states. nized as the minimal moisture level where Fusaria What are its effects? mycotoxin activity occurs. Three known factors produced by this mold What Treatment is Available? cause feeding problems to animals consuming it. Producers of Gibberella zeae contaminated com The “refusal factor” — animals refusing to eat it — have very little means available to reduce the the “emetic factor” — vomiting — are present in problem. Both the emetic and refusal factors are the contaminated grain, and result in reduced very stable to pH changes (pH 2.0-11.0) and to nutrition. The third factor, a plant estrogen, is heating (190°F for 5-10 minutes). The use of associated with female reproductive disorders, such roasting procedures, molasses cover up, additions as abortion and infertility, particularly in swine. A of sodium hydroxide (up to 10% of the weight of fourth factor should be mentioned — T-2 toxin, a the corn) and spraying with propionic acid and very toxic substance to both man and animals, is acetic acid, have all been useless in reducing the produced in small quantities by Gibberella zeae. refusal factor. Steam flaking (cattle feed proce­ What are the symptoms? dure) and flotation of the contaminated com in a Refusal to eat contaminated corn is the most salt solution are currently being experimented with striking symptom in swine. There also are isolated to reduce the refusal factor activity. The trials are reports that poultry and cattle will refuse to eat it. not completed but poor results were indicated in The refusal factor apparently becomes a problem the initial feedback of information in these trials. when infection occurs in about 5% or more of the What FDA is doing kernels. (The observed levels found in the field this The principal activity of FDA shall be surveil­ past year ranged from 5 to 7%). In addition, weight lance of human and animal foods to protect both loss and occasionally death may occur as toxin from food intoxications. FDA programs are regula­ levels increase. Abortions in swine are caused by tory by nature; animal or human foods the naturally occurring estrogenic factor. contaminated with Gibberella zeae. are subject to seizure. The problems of the producers, shippers, Why is FDA concerned? processors (and FDA) will be reduced if FDA The Bureau of Veterinary Medicine (BVM) is makes it clear in advance what is expected of those concerned with the effect that contaminated grain individuals and firms that are subject to the may have on the health of animals consuming provisions of the law. FDA recognizes that Gibberella zeae and, because of a potential hazard, preventive regulatory action is a necessary part of the controls that might be needed on feed grain to prevent possible transmission of a toxic residue in the regulatory equation and this will require close animal tissues. FDA’s Bureau of Foods (BF), in cooperation with the public and industry. Research addition, is concerned with both the effect of and education may also be included among the Gibberella zeae in human foods, and the potential preventive measures taken. for tissue residues entering the human food chain. Veterinarians and Commercial Feed Mixers What is the background? What is the problem ? Gibberella zeae contamination of com has been Veterinarians and feed mixers may not realize 67 their responsibility for the use of drugs and feed Unless the drug premix manufacturer has sub­ Association Practitioners; Bovine open ofdistribution. access American Copyright © additives fed to animals. Part of this responsibility mitted data for FDA’s review and received relates to any illegal residue left in animal tissue at approval for any new uses, he cannot mix and sell the time of slaughter. unapproved products. This also applies to other What is F D A policy ? levels of the drug alone or combinations of drugs. A veterinarian may prescribe and administer to What are veterinarians responsible for then? his patients whatever drugs or other medicaments In addition to their patient’s health and safety, he may legally obtain. This constitutes the practice veterinarians must be aware of their. possible of veterinary medicine which is subject to state liability for residues found in food derived from laws and not under FDA regulation. food-producing animals. Any prescribing of drugs How does this involve feed mills? in feed which causes a residue could result in If a veterinarian enlists the services of a feed mill federal legal action against a veterinarian for having to mix drugs into a feed on a “prescription” basis, contributed to the shipment of adulterated food. a third party to the doctor-client relationship has This is because animals moving to slaughter are 4 been introduced. This goes beyond the “practice” considered to be food under interpretation of the of veterinary medicine. This “third party” relation­ Food, Drug, and Cosmetic Act. ship makes such uses subject to FDA regulations. What should a veterinarian tell his client?, When can feed be manufactured? Aside from the usual doctor-client relationship, The feed mill is considered a commercial a veterinarian should emphasize withdrawal times operation when it adds drugs to feed. Therefore, it to livestock producers. This is especially true of is subject to the Food, Drug, and Cosmetic Act. any products he may have used in the treatment of Under this statute, a feed mill may not manu­ his clients’ food-producing livestock. Also, he facture feed unless it is approved and, as in the case should remind his client to carefully review all of new animal drugs requiring approval, the mill medicated feed labeling for warnings of proper holds an approved medicated feed application usage and withdrawal times. (Form 1800) for a drug or combination. Also, the Acknowledgemen ts feed has to be labeled in accordance with the The above information was received from l)r. Thomas B. approval. Snodgrass. Food and Drug Administration, Dallas District, 3032 Bryan Street, Dallas, Texas 75206. Are other persons responsible? No veterinarian, practicing or employed by a FDA Orders End to Use of Implants of DES feed manufacturer, nutritionist, pathologist, or any The Food and Drug Administration on April 25 manufacturer—may authorize the using of feeds with drugs or drug combinations that are not ordered an end to the use of implants of approved for animal feeds. Any individuals so diethylstilbestrol (DES) in beef cattle and sheep. doing may be held responsible if drug tissue The action is based on new scientific data residues are found in treated animals resulting from developed by the USDA and received by FDA on the use of such unauthorized medicated feeds. April 16. This study, which used a highly sensitive radioactive tracer research technique, showed the Why is there this strict control over use in feed? presence of DES in the livers of beef cattle 120 FDA reviews each drug or combination on the days after DES was implanted in the animal’s ear. basis of the data received. Approvals are given only Confirmed levels of DES ranged from 0.04 p.p.b. for certain uses or claims at certain levels. These (from a half dose of DES) to 0.12 p.p.b. (from a are published in the federal regulations. Before a full dose). FDA conducted analytical work to new animal drug is marketed, FDA does a confirm that the residues were DES. thorough preclearance review. Based on submitted Last August, FDA banned DES from use in data, the review is designed to ensure that the drug animal feed after a similar study showed residues in (1 ) will be safe and effective and (2) will not cause the livers of animals fed DES. The current study is tissue residues beyond a permitted level. the first in which residues have been traced to the Unapproved drug levels or combinations are not use of DES implants. Previously, tests conducted permitted because there is no review history of with less sensitive methods had not shown the data that substantiates their safety and effective­ presence of DES residues after use of implants. ness. In today’s order, FDA rejected requests for a What about other drug uses? hearing from the six manufacturers of DES The same requirements prevail for manu­ implants. The agency ordered an end to all further facturing any medicated feed or custom mix. use of implants, effective April 27. Animals already 6 8 implanted, or meat from already slaughtered organism from the lethal effects of the cidal drug, Association Practitioners; Bovine open ofdistribution. access American Copyright © animals, may be marketed without disruption.