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M. Friend

Publications and source records attributed to M. Friend.

41 records · Page 3Linked to original sources
USGS1976

Wildlife diseases: philosophical considerations

Wildlife diseases are studied because of their adverse impact on human health, agriculture, or wildlife conservation. Viewpoints from these three major areas of concern are not always compatible, yet the ecological nature of disease makes it essential that each is recognized and understood. Within wildlife agencies, resistance or apathy toward controlling wildlife disease arises because: (1) seldom is this action initiated primarily for the direct benefit of wildlife, (2) the action may be at the direct expense of wildlife, (3) there has been little to demonstrate that wildlife diseases can be controlled in free-living wild populations, and (4) the role of disease in the population dynamics of wildlife species has not been adequately documented and, as a result, the importance of many diseases has not been ascertained. In addition to knowing better the effects of disease on the population dynamics of wildlife species, it is essential to investigate chemical-microbial and chemical-parasitic interactions. Greater efforts must be made to prevent the introduction of disease into wildlife populations and to control disease when it occurs. Although management of wildlife populations often parallels intensive agricultural operations, knowledge of animal husbandry and associated disease problems in domestic animals has not been adequately utilized. As a result, disease problems are created that might otherwise be avoided or reduced in magnitude. If we are to be successful in controlling diseases of wildlife, each of us must translate his knowledge into forms that will utilize differing viewpoints in the resolution of common problems.

Book chapter↗
USGS1973

DDE: Interference with extra-renal salt excretion in the mallard

The effects of DDE on the function of the salt gland, the main route of sodium chloride excretion in marine birds, were investigated in mature mallards, Anas platyrhynchos, maintained on either fresh water or 1 percent salt water and given 0, 10, 100, or 1000 ppm DDE in the diet (12 birds per level). The rate of sodium chloride excretion by the salt gland following injections of concentrated salt solutions was not reduced (from that of controls) in DDE -treated birds maintained on salt water, but was significantly reduced in DDE -treated birds not previously given salt.

Bulletin of Environmental Contamination and Toxico↗