Rats, animal testing

CS analyses on 1-cm segments Study of hair levels albino vs. pigmented rats (animal test), and black vs. white hair (human test) CS analysis on 1-cm segments CS analysis on 1-cm segments Subjects given (A) a single dose of 600 mg, or (B) 900 mg/d for... 

The toxicity of these fluoroaluminates is mainly as inorganic fluorides. The ACGIH adopted (1992—1993) values for fluorides as F is TLV 2.5 mg/m. The oral toxicity in laboratory animal tests is reported to be LD q rat 2.15 mg/kg (41). Because of the fine nature of the products they can also be sources of chronic toxicity effects as dusts. 

Iversen (1991) stresses the need for some in vivo testing for neurotoxicity and emphasizes the value of sensitive behavioral tests. Behavioral tests are described for mice and rats, which provide measures of mood, posture, CNS excitation, motor coordination, sedation, exploration, responsiveness, learning, and memory function. Such assays can function as primary screens for neurotoxicity before adopting a stepwise scheme of in vitro tests to discover more about the initial site of action of neurotoxic compounds. It is argued that the requirement for animal testing can be drastically reduced by adopting structured in vitro protocols such as these. 

To determine the toxicity of parathion to warmblooded animals, tests were made with mice, rats, guinea pigs, rabbits, and dogs. Greatest hazards are associated with insecticidal use, but symptoms of toxicity may be detected well in advance of severe toxic actions. 

We can, of course, combine a number of observations to allow ourselves to actively test for a set of trends, such as the existence of a trend of increasing difference between two groups of animals over a period of time. This is demonstrated in Example 22.1. In a chronic feeding study in rats, we tested the hypothesis that, in the second year of the study, there was a dose responsive increase in tumor incidence associated with the test compound. We utilize a Cox-Stuart test for trend to address this question. All groups start the second year with an equal number of animals. 

From Bressani et al. (37). Wistar rats were test animal, b —... 

Two rabbits which survived 118 periods of exposure to 0.36 ppm (15 mg/m3) of endrin vapors developed a granulomatous pneumonitis (Treon et al. 1955). The pneumonitis was not observed in cats, guinea pigs, hamsters, rats, or mice, but the small number of animals tested limits the usefulness of this study. 

The TER assay of rat skin is a fully accepted replacement method of animal tests for skin corrosion. Hence, in the EU the TER assay is mandatory for the evaluation of test substances. Investigation of animals to test the corrosivity of chemicals and/or other substances is not permitted [151],... 

In a review. Arts and Kuper (2007) have summarized the animal test methods, which have been used to detect immune-mediated respiratory disease. The tests for respiratory sensitization include dermal as well as inhalatory or topical exposure of mice, rats, or guinea pigs for induction and challenge, and may measure various endpoints to evaluate respiratory sensitization. The review concludes that standardized and validated dose-response test methods are urgently required in order to allow identification of respiratory allergens and to make it possible to recommend safe exposure levels for consumers and workers. 

Comprehensive toxicity studies are carried out by animal testing in order to ascertain whether the product exhibits any short-term or long-term toxicity. Acute toxicity is usually assessed by administration of a single high dose of the test drug to rodents. Both rats and mice (male and female) are usually employed. The test material is administered by two means, one of which should represent the proposed therapeutic method of administration. The animals are then monitored for 7-14 days, with all fatalities undergoing extensive post-mortem analysis. 

The implementation of animal test protocols in the 1980s has been accompanied by the development of a host of alternative methods to study adverse effects of chemicals on reproductive and developmental parameters. For example, rat whole embryo culture stems from the seventies (16), as does the rat limb bud organ culture (17) and rat limb bud and brain micromass was developed in the eighties (18). An elegant nonvertebrate alternative model used regeneration of polyps of Hydra atUnuata from dissociated cells (19). Animal-free in vitro alternatives include those employing the proliferation of a human embryonic palatal mesenchymal cell line (20), the attachment of a mouse ovarian tumor cell line (21), and the differentiation of a neuroblastoma cell line (22) and a embryonal carcinoma cell line (23). Various overviews of methods have been published over the years (24). The predictability of... 

Gori (1991, 226) says, "to defend animal tests by saying that most of the few known human carcinogens are also carcinogens in animals is a classic non-sequitur all rats are mammals therefore all mammals are rats."... 

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