Target animal safety

The relevance of the target-animal safety test for batch safety testing of vaccines for veterinary use EU... 

Japan. In Japan, registration of dmgs for aquatic species requires the same data as those required for dmgs on other animals. The Ministry of Agriculture, Eorests, and Eisheries and the Ministry of Welfare control the use of chemicals in aquaculture in Japan (17). The preclinical data requirements include product chemistry, toxicity (acute, subacute, special) using rats and mice, safety to target animals, and metaboHsm. The requirements for clinical data include avadabiHty and residues. As of July 1990, more chemicals were registered for aquacultural use in Japan than in any other country (Table 4). 

Clinical trials must be conducted to establish safety in each target animal species which, in the majority of cases, will include food-producing species. Although the same types of animal may be involved in both pre-clinical and clinical trials, dear distinctions can be drawn between each type of study. Pre-clinical studies are only conducted in animals that are kept for the purposes of laboratory research, and that are usually maintained in a very controlled environment. Clinical trials, on the other hand, are conducted in animals that are representative of the normal conditions (field conditions) and purposes for which they are maintained. 

Today, in the United States, the FDA is responsible for examining safety and efficacy data before an antibiotic or synthetic chemical may be commercialized for livestock use. This includes studies on formulations, product stability, conventional and genetic toxicity, environmental safety, metabolism, residue studies in target animals, studies on antibiotic resistance in gut microflora and on salmonella shedding in target animals. Similar requirements are part of registering these products in overseas markets. In general, after a product is discovered in the laboratory, many... 

A major food safety issue addressed by the European Union concerns the increase in the level of circulating insulin-like growth factor (IGF-I) in the target animal and its increased excretion in the milk as a consequence of the administration of rBST. There has been epidemiological evidence for an association between circulating IGF-I levels and the relative risk of breast and prostate cancer (34-36). 

Since the animal drug amendments of 1968, veterinary drugs have had their own section of the Code of Federal Regulations (CFR), section 512. Under this section the sponsor of a new animal drug is required to demonstrate not only the efficacy of the drug, but also the safety to the target animal. These studies must be scientifically valid and well controlled to support the approval and are codified in 21 CFR 514. 

For veterinary drug delivery systems, additional requirements exist in regard to safety when compared with delivery systems for human. Besides the safety of the target animal, consumer safety is also important. Particularly for food-producing animals, because these animals enter the food chain, tissue residues must be addressed for both the drug and the polymer. Environmental safety should also not be affected. In view of these requirements, being a nontoxic, nonallergenic, biocompatible natural polymer, chitosan can be considered as a safe polymer for veterinary applications. 

Many compounds with adjuvant activity are presently known (shown in Table 12.2) but only a few are applied routinely in human and veterinary vaccines. The application of the novel adjuvants are limited for several reasons, such as disappointing efficacy in the target animal species, insufficient safety, problems with large-scale preparations, and limited stability of the final formulations. Many studies have reported on O/W and W/O emulsions used as adjuvants and delivery systems for immunization (Hilgers et al., 1994a, b, 1999). The adjuvanticity of the W/O/W makes this type of multiple emulsion a suitable delivery system for immunization with prolonged release, and its interesting preparation is presented below. 

Safety factor increased by a factor of 2 due to the small difference between the NOEL and the therapeutic dose which caused side-effects in target animals. 

B. Roberts and R. N. Lucken, Reducing the use of target animal batch safety test for veterinary vaccines, Dev. Biol. Stand., 1996, 86, 97-102. 

At a minimum, the method will be tested in one FDA laboratory and two contract laboratories selected by the sponsor. If the method is for a new animal drug in tissue regulated by the United States Department of Agriculture (USDA) as part of the meat inspection program, a Food Safety and Inspection Service (FSIS)/USDA laboratory will be included if sufficient resources are available. The method trial will be conducted using control and incurred target tissues that are supplied by the sponsor. The sponsor may, on request, supply new or unusual reagents or standards. 

Pig production today faces the difficult task of effectively meeting emerging consumer concerns while remaining competitive in its major target markets. Providing a high sensorial quality of pork and meeting consumer concerns about product safety and animal welfare are identified as key attention points for future livestock production. The relevance of these issues pertains to... 

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