Veterinary practice

Nuts have many uses, both industrial and domestic. For instance, the ivory nut, or tagua, is a source material for the manufacture of buttons and turnery articles. The kola nut supplies ingredients for popular cola beverages in the United States (see Carbonated beverages). StTychnos nux-vomica provides the important medicine and poison, strychnine. The areca or betel nut is chewed by the Indian and Malayan people as a narcotic a slice of the nut is placed in a leaf of the pepper plant Piper betle) together with a pinch of lime the mixture is an acrid, astringent narcotic that dyes the mouth red, blackens and destroys the teeth. The areca nut contains, among other alkaloids, arecoline, an active anthelminthic widely used in veterinary practice for the treatment of tapeworm infections. 

Carbamylcholine chloride [51 -83-2] is also called carbachol (47). Its principal use is as a parasympathornimetic in veterinary practice for large animals. 

Y. Debuf, The Veterinary Formulary Handbook of Medicines Used in Veterinary Practice, The Pharmaceutical Press, London, 2nd edn., 1994. 

Alkylation of the 5(4)-nitro compound with methyl sulfate in nonpolar solvents affords dimetridazole (91), ° an antitrichomonal agent used in veterinary practice. Alkylation with chlorohydrin leads to metronidazole (92), a drug that has found widespread use in the treatment of vaginal trichomoniasis. Finally, alkylation by means of iv-(2-chloroethyl)morpholine affords nitrimida-zine (93),... 

VinyIpyridine (26) exhibits many of the properties of a Michael acceptor. Thus, this molecule will undergo conjugate addition of methoxide ion. There is thus obtained methyridine (27), an antinematodal agent used in veterinary practice. 

Amides and carbamates of 2-ami nobenzimidazole have proved of considerable value as anthelminic agents, particularly in veterinary practice. A very considerable number of these agents have been taken to the clinic in the search for commercially exploitable agents. (See the section on Benzimidazoles in Chapter 11 of Volume 2 of this series.) A small number of additional compounds have been prepared in attempts to uncover superior agents. 

In Section 4.3, some factors which need to be considered in choosing a method of analysis were discussed in general terms. The next step is to consider the properties of a method that will enable a choice to be made. This is done for a specific case, e.g. the determination of residues of chemicals used in veterinary practice to treat animal diseases and to prevent the development and spread of disease where large numbers of animals are kept in close proximity to each other. Such chemicals may be administered by injection, or orally as a constituent of the feed. Some chemicals are metabolized and excreted while others may be partially retained in edible products such as milk, eggs, meat and offal (liver or kidney). The detection and determination of such residues is a very difficult analytical problem. 

In Europe about 10,000 tons of antibiotics are consumed each year (FEDESA, the European Animal Health Association 1998) [59] (see Table 2). According to these data, 5,000 tons are due to veterinary purposes (3,500 tons prophylaxis and therapy, and growth promotion about 1,500 tons). The other half of production is used in medicine. Among the antibiotics used in veterinary practice,... 

Chloramphenicol [20 CAP D-(—)-ft reo-l-(p-nitrophenyl)-2-(dichloroacetamido)-l,3-propanediol] is an important antibiotic due to its broad activity against a number of clinically relevant microbial pathogens and its ability to penetrate easily the blood-brain barrier. Besides human application, CAP became widely and routinely used in veterinary practice and is used in Europe in most animal productions including fish128. 

I conclude that the results in Great Britain and other European countries show that banning the use of penicillin and tetracyclines in animal feeds has had no measurable effect on the prevalence of antibiotic resistance, presumably because of the continued use of these antibiotics in human and veterinary practice. 

Monensin plays a dual role in veterinary practice because it is used both as a coccidiostat in poultry and as a growth promotant in cattle. It is also efficacious in the control of coccidiosis in lambs and calves, can treat ketosis in dairy cows, and can control bloat in pastured dairy cattle. It is administered incorporated in poultry feeds as a coccidiostat at a dose up to 120 ppm, and in cattle and sheep feeds at a dose of 11-33 ppm. Monensin is not recommended for administration to laying hens, while a 3 day withdrawal period is required for chicken meat. 

Nonsteroidal anti-inflammatory drugs are widely used in veterinary practice and are, therefore, of growing interest to the residue control of animal-derived food. Veterinarians are seeing an increased use of anti-inflammatory agents, administered with or without antibiotics, for treatment of mastitis because of the increase in efficiency of these agents over antibiotics alone. 

Xylazine is widely used in veterinary practice for its potent sedative, analgesic, and myorelaxant properties. It may be administered intramuscularly or intravenously to all animal species, although not to pigs due to the very high dose rates required. 

An example of the application of this procedure for testing the equivalence of the albendazole or ivermectin MRLs for which differences exist between the United States and JECFA is presented in Table 12.5. Differences between US and JECFA MRLs for albendazole are due to use of different safety factors and to the JECFA consideration of good veterinary practice. That is, JECFA considered practical conditions of use of the drug and set MRLs consistent with that use accordingly, the entire ADI is likely not to be consumed. On the other hand, the United States always uses the entire ADI in setting MRLs for edible tissues. 

Analgesic efficacy and medical use Etorphine (Wallach, 1969) is one of the most potent synthetic opioids with a potency 400-1000-fold higher than morphine. In addition to ist analgesic properties etorphine induces potent CNS depression and is mostly used in veterinary practice for anesthesia, immobilization and pain treatment of large animals (Alford et al.,1974). 

Bismuth and its compounds have traditionally been widely used in medicine and veterinary practice. Finely divided bismuth was injected intramuscularly as an aqueous suspension in the... 

Antibacterial drugs are used in veterinary practice for two purposes as therapeutics or prophylactics to control clinical disease, and as feed additives to enhance growth performance of animals. The latter practice presumably depends on the antibacterial action of the drug, even though it is used in low, subtherapeutic doses. The effect thus produced is to be distinguished from the action of a true growth promoter, e.g. monensin (63), and will be discussed in detail later (Section 1.08.6.3). Here we shall consider only the therapeutic/prophylactic properties of antibacterial agents. 

Some representative /3-lactam drugs used in veterinary practice are benzylpenicillin (17), ampicillin (18), amoxicillin (19), cloxacillin (20), penethamate (21) and cephalexin (22). 

The sulfonamide antibiotics were the first synthetic antibiotics to have general utility in human therapy (B-79MI10806). Of the numerous compounds thus developed, comparatively few are presently used in veterinary practice. They include sulfapyridine (40), sulfamethazine (41) and sulfadimethoxine (42). They are much less potent than the /3-lactams (dose 100-200 mg kg-1), and have a bacteriostatic effect. They are commonly used in combination with trimethoprim (43), when a synergistic effect is observed, i.e. the combination is more potent than either drug alone, and species of bacteria which are unaffected by the drugs individually are susceptible to the combination. 

Zinc phenolsulfonate has been used in insecticide formulations and in veterinary practice for the treatment of ulcers. Zinc phosphate has been used in dental cement formulations and the phosphide in rat and field mice poisons. The propionate has been used as a fungicide on adhesive tape to reduce plaster irritation caused by moulds, fungi and bacteria the silicate has been used in television screens. 

---