Animal health in organic agriculture: new guidelines and perspectives for food animal practitioners

In the last decade, the organic agriculture in Switzerland has been substantially increased due to the interest of consumer and financial incentives of the federation. Ruminants take directly or indirectly the largest part from grassland used within the organic managed surfaces. As the contacts between veterinary practice and organic agriculture has increased, the potential for veterinary activity in this area has developed considerably. The organic agriculture guidelines stipulate that all the preventive measures should be taken in feeding, keeping and breeding to insure animal health safety. This requires veterinary services for herd management. The organic status of a farm affects veterinary practice also in the form of alternative therapy/drugs administration and measures like dehorning and tail-docking. An important point in organic managed herds requests that treatment of animals should depend on alternative medical preparations or procedures based on veterinarian's experience and also on the therapeutic effect on the animal species concerned as well as on the disease. However, there are no restrictions on the veterinarian to use registered drugs as long as no alternative therapy, according to experience and possible success, is available to treat the animals. The prophylactic administration of allopathic veterinary drugs is not permissible. Further features in organic farms regarding the use of drugs are the keeping of withholding/withdrawal time, the documentation and the treatment frequency tolerated by organic marketing. Despite the above measures, the animal health has a priority regardless of its organic status. Although management of organic farms represent a unique responsibility, there are still obvious deficits in the education of veterinary practitioners for this new situation. However, in the future the extension of veterinary activity to include the alternative medical therapy should be regarded for the practitioner as a challenge and an opportunity at the same time.     

Diagnostic toxicology for the food animal practitioner.

In most competent veterinary diagnostic laboratories, analytic findings are interpreted by a veterinary toxicologist to determine the significance of the finding in light of historical, clinical, and pathologic findings. A veterinary toxicologist also provides consultation about possible toxic rule-outs for a case, treatment of affected animals, and prevention of additional cases. Once all of the information is available, a complete summary of the findings can be provided to the client. When the procedures outlined herein are followed, including a systematic approach to collecting all the evidence (historical, clinical, pathologic, and analytic), using proper sampling techniques, and maintaining good communication among the clinician, client, and laboratory, the usefulness of the toxicology investigation is maximized.     

Molecular diagnostics for the food animal practitioner.

Molecular diagnostics are becoming widely used as routine diagnostic tests performed by food animal practitioners. This article discusses the variations of several commonly performed molecular assays with regard to their molecular basis and the appropriate interpretation of the results. Applications of these methods are discussed in the context of infectious disease testing and genetic testing of food animal species.     

Cytology in food animal practice.

Diagnostic cytology can greatly aid the clinician in determining a more refined diagnosis, prognosis, and treatment plan to serve the client and patient better. Sample collection is not difficult and can be done in the field as well as in a hospital setting. The collection and sample handling procedures described in this article can help the clinician to obtain diagnostically valuable samples. In many cases, preliminary cytologic evaluation can be performed by the general practitioner. Additional diagnostic evaluation and interpretation are readily available from trained pathologists at diagnostic laboratories.     

Current status of food animal antidotes.

The availability of antidotes in veterinary medicine has been an issue for more than a decade. Antidotes are available for food animals through extralabel use, regulatory discretion, and compounding. There is little economic incentive for pharmaceutical companies to pursue approval of antidotes and other drug products that have a small market. In addition, human food safety concerns must be addressed when approving antidotes for use in food animals. This article provides a brief history of antidote availability, current mechanisms for procuring food animal antidotes, and availability of specific antidotes for use in food animals.     

Disease outbreak investigation in food animal practice.

In addition to excellent observation skills and a good understanding of production medicine, veterinarians require the tools of epidemiology for the successful investigation of disease outbreaks. Food supply veterinary practitioners are often called upon to investigate various types of disease outbreaks. In this article, the authors outline the primary questions a practitioner should address and summarize a systematic approach to determining the causes of an outbreak and minimizing further losses. The investigation of disease outbreaks provides an opportunity for the herd veterinarian to show clients the advantages of a herd health program and the value of a good record-keeping system.     

The benefits of animal identification for food safety

The Center for Veterinary Medicine supports the effort to have a practical, workable form of mandatory animal identification. An animal identification system will make tracing of the source of animals with drug or chemical residues quicker and more effective. One of the best means of addressing and solving the problem of residues is through mandatory livestock identification. A successful traceback benefits both the producer and the industry. The U.S. Department of Agriculture (USDA) has proposed a mandatory nationwide system to require that all swine in interstate commerce be identified. Under the proposal several means of identification are listed and could be used. Additional methods or devices could be requested in writing to USDA. Persons required to keep records under the system would maintain the documents at their place of business for 2 yr. Records would be available to authorized USDA employees during ordinary business hours. FDA has had difficulty tracing tissue residue violations, particularly those involving sulfamethazine residues in swine. Investigations involving culled dairy cows and veal calves also have been closed due to lack of producer identification. The ability for FDA to determine the source of residues is vitally important in a coordinated government program to eliminate illegal tissue residues.     

Mycotoxins. Contemporary issues of food animal health and productivity.

Modern agriculture and production animal medicine require attention to high-quality feeds that are free from mycotoxin contamination that can cause economically important decreases in productivity. Maintaining current information about effects of mycotoxins on feed intake and growth, reproductive efficiency, and possible immunosuppression aid in effective consultation with livestock producers. Investigation and determination of potential production losses related to mycotoxins should use historical, clinical, laboratory, and experimental information to objectively evaluate whether mycotoxin contamination is clinically relevant. The practicing veterinarian or veterinary consultant can provide valuable clinical and interpretive assistance to producers who may have a real or potential mycotoxin contamination. Thorough diagnostic evaluation of animals, appropriate testing of feeds and forages, and rational consideration of differential diagnoses help to put mycotoxins in the proper perspective as a production-related management problem.     

动物采食量生理调控物质的研究进展

在动物生产中,提高动物的采食量一直是科学工作者非常关心的问题,提高采食量可以提高动物的生产性能,特别是高产奶牛、仔猪、肉鸡等高生产性能的动物,采食量可能是限制其生产性能发挥的重要因素。影响动物采食量的因素很多,有生理因素(包括遗传、神经和激素、感觉因素等);环境因素(温度、湿度、空气流动、料槽设计和位置、密度以及每圈动物数);日粮因素(养分的缺乏和过量、能量浓度、抗生素、调味剂、饲料加工及水的质量)等(NRC,1998)。而生理因素是最根本的,日粮因素和环境因素很可能通过生理因素发挥作用。采食量的控制非常复杂,包括体…