Showing papers on "Animal mortality published in 1976"

Effect of Sodium Intake on Gentamicin Nephrotoxicity in the Rat

Abstract: SummaryGentamicin nephrotoxicity was examined in rats on normal, high, and low sodium diets. Low sodium diet markedly potentiated nephrotoxic effects of the drug as evidenced by animal mortality, renal failure, pathological changes, and increased renal cortical concentration of the drug. High sodium intake reduced the cortical concentration of gentamicin but renal function and ultrastructure were similar to normally fed rats given in the same dose.

An Attack by a Polar Bear on a Juvenile Beluga

Abstract: Cunningham Inlet, Somerset Island, in the Canadian Arctic is frequented each summer by large numbers of beluga ( Delphinapterus leucas ). They migrate to the head of the inlet, and then invade the mouths of the two streams which drain into it. … On 26 July 1974, a sexually-immature female beluga was discovered stranded on a gravel bar at the head of the inlet. Because it could not be manhandled back to water, and would have died from suffocating and dehydration, the whale was shot. The brown colour, shape of head and length (271 cm) of the animal suggested that it was between three and four years old, while the five to six growth layers present in the teeth indicated an age of 2½-3 years. The stomach was found to contain a few amphipods and some seaweed. The carcass carried deep but well-healed scars on the left dorso-lateral aspect caudal to the dorsal ridge. Their depth, and the fact that they were parallel in three cases, strongly suggested that the animal had been attacked by a large-clawed animal, probably a polar bear (Ursus maritimus ). … To our knowledge this paper constitutes only the third documented account of an attack on a beluga by a polar bear in the Canadian Arctic …. [All previously reported attacks, including an attack of captive belugas near Churchill, are also discussed in this article.]

A large sample investigation of a multiple decrement life table estimator

Abstract: A widely used multiple decrement life table estimator, designed to deal with grouped and censored data, is rigorously defined and investigated. The relationship of the estimator to the problem of competing risks is also discussed, and its large sample covariance structure is worked out. The results of this paper may be applied not only in the study of human and animal mortality but also in evaluating the use-effectiveness of contraceptives, where incorrect formulas for estimating standard errors have sometimes been used.

Evaluation of the smoke density chamber as an apparatus for fire toxicity screening tests

Abstract: The smoke density chamber is perhaps the most widely used apparatus for smoke measurements. Because of its availability, it has been proposed as an apparatus for evaluating fire toxicity. The standard apparatus and procedure were not found suitable for toxicity screening tests using laboratory animals, because not enough materials of interest produced animal mortality or even incapacitation under standard test conditions. With modifications, the chamber offers greater promise as a screening tool, but other tests specifically designed to measure relative toxicity may be more cost-effective. Where one-dimensional heat flux is a requirement, the chamber is the most suitable apparatus available. It should be improved in regard to visibility of animals and ease of cleaning.