Diseases In Food Animals Research Articles

Quinolone resistance in Escherichia coli.

Escherichia coli is an important pathogen of animals and humans that causes great financial cost in food production by causing disease in food animals. The quinolones are a class of synthetic antimicrobial agents with excellent activity against Escherichia coli and other Gram-negative bacteria used in human and veterinary medicine. Different quinolones are used to treat various conditions in animals in different parts of the world. All members of this class of drug have the same mode of action: inhibition of topoisomerase enzymes, DNA Gyrase and Topoisomerase IV. Escherichia coli can become resistant to quinolones by altering the target enzymes, reducing permeability of the cell to inhibit their entry, or by actively pumping the drug out of the cell. All these resistance mechanisms can play a role in high-level fluoroquinolone resistance, however target site mutations appear to be most important. As all quinolones act in the same way resistance to one member of the class will also confer decreased susceptibility to all members of the family. Quinolone resistant Escherichia coli in animals have increased in numbers after quinolone introduction in a number of different case studies. The resistance mechanisms in these isolates are the same as those in resistant strains found in humans. Care needs to be taken to ensure that quinolones are used sparingly and appropriately as highly resistant strains of Escherichia coli can be selected and may pass into the food chain. As these drugs are of major therapeutic importance in human medicine, this is a public health concern. More information as to the numbers of quinolone resistant Escherichia coli and the relationship between resistance and quinolone use is needed to allow us to make better informed decisions about when and when not to use quinolones in the treatment of animals.

Vaccination in food animal populations

This report highlights the role of vaccination in the present and future food animal industry in the framework of the disease policy of the European Commission. Vaccination was essential in the virtual eradication of foot-and-mouth disease and classical swine fever, the use of modern marker vaccines opens prospects for eradication of viruses in countries with a high prevalence, and a rebirth of interest in bacterial vaccines is noted, because of the problems of drug resistance and antimicrobial residues. Biotechnology has already led to the development of several new vaccines, and to the improvement of current vaccines, and it still holds great potential for designing basically novel vaccines. Vaccination, thus, is a crucial tool in reducing the enormous economic losses caused by diseases in food animals.

Federal regulation of drugs administered through feed

It is a pleasure for me to be part of this program on nutrition and nutritional diseases in food animals. Although my formal education was in animal nutrition, it has been very difficult to keep up with new advances. In fact, it has been difficult to maintain a working knowledge in amino acid nutrition, an area I spent many years researching. Therefore, I intend to listen attentively to what is said by others from this podium.

Clinical Experiences with White Muscle Disease

For many years veterinarians saw clinical cases and read reports of primary myopathic diseases in food animals and the equine. During the 1950's and the 1960's, investigative research teams found one of the probable causes to be a deficiency of either alpha tocopherol and/or selenium in the diet. Since this breakthrough, innumerable clinical manifestations of white muscle disease (WMD), selenium responsive disease (SRD), or selenium alpha tocopherol deficiency (STD) have been encountered.