Results 181 to 190 of about 887,351 (211)

Eggshell thickness in mallards fed methylmercury

Bulletin of Environmental Contamination and Toxicology, 1980
Eggshell thinning has been linked to impaired reproduction in many wild birds. Previous work of my own and others led me to believe that methylmercury may cause some eggshell thinning in birds. The present study was designed to determine whether methylmercury in the diet of mallards would thin their eggshells and whether it would add to eggshell ...
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Bone parameters of thick and thin eggshell lines of chickens

Comparative Biochemistry and Physiology Part A: Physiology, 1984
Comparative measurements of bone parameters were made on chickens from thick and thin eggshell lines that were maintained on a normal diet containing 3.5% calcium, injected i.v. with 45CaCl2 and sacrificed 30 min later. There were no significant differences between shell lines for the following measurements on the left femur: specific gravity, ash wt ...
E G, Buss, R B, Guyer
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Effects of dietary mercury and lead on eggshell thickness in mallards

Bulletin of Environmental Contamination and Toxicology, 1974
Experiments were performed to determine whether mercury and lead in the diet of captive mallards (Anas platyrhynchos) would increase the eggshell thinning above that caused by DDE alone. DDE alone caused a 15% reduction in shell thickness, but neither Pb and Hg contributed significantly to mallard eggshell thinning, nor did these compounds appear to ...
M A, Haegele, R K, Tucker, R H, Hudson
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Comparison of breaking strength and shell thickness as evaluators of eggshell quality

Environmental Toxicology and Chemistry, 1988
Abstract The shell quality of eggs produced by northern bobwhite (Colinus virginianus) dosed with sulfanilamide was evaluated by a compression breaking strength test and by the shell thickness measurements that are used in the U.S. Environmental Protection Agency avian reproduction test to determine the effect of a chemical substance on ...
Richard S Bennett
exaly   +2 more sources

Embryonic eggshell thickness erosion: A literature survey re-assessing embryo-induced eggshell thinning in birds

Environmental Pollution, 2015
Although eggshell thinning has been described mainly in the context of environmental pollution, it can also be the effect of reproductive changes induced by a developing embryo. On the basis of a literature survey of 25 bird species (26 published papers) we reviewed data on embryo-induced eggshell thinning (EET) in three groups of birds: precocials ...
Grzegorz Orłowski, Lucyna Halupka
exaly   +3 more sources

DDE Residues and Eggshell Thickness in Prairie Falcons

The Journal of Wildlife Management, 1973
The eggshell thickness of prairie falcon (Falco mexicanus) eggs collected in Colorado in 1967-68, and 1972, is related linearily and inversely to the logarithms of the DDE content of the eggs. This relationship is not statistically different from that found in peregrine falcons (F. peregrinus) and brown pelicans (Pelecanus occidentalis).
James H. Enderson, Peter H. Wrege
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Reproductive correlates of eggshell thickness in European woodpeckers

Ornis Norvegica, 2008
Woodpeckers excavate their own nesting holes, have small eggs relative to their body size and many species have small clutches. Based on data from the eight European woodpecker species it was found that the mean thickness of eggshells increases with egg volume, whereas large woodpeckers lay smaller eggs with thinner eggshell relative to their body mass.
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A Comparative Study of Eggshell Thickness in Cowbirds and Other Passerines

The Condor, 1987
We directly measured the eggshell thickness of the three brood parasitic Molothrus cowbirds, 17 other icterids, and 13 additional passerines. By correcting these shell thickness measurements for variation attributable to interspecific differences in egg volume, we show that the Molothrus cowbirds lay eggs with shells that are 30% thicker than expected ...
Spaw, Carol D., Rohwer, Sievert
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Eggshell thickness and porosity in budgerigars and their relationship to hatch‐ability

Journal of Small Animal Practice, 1992
ABSTRACTAs part of an investigation into low chick production in relation to the number of eggs laid by exhibition budgerigars, a study was carried out into the role, if any, of shell thickness and porosity to water vapour. Shell thickness was the same in clear eggs, fertile eggs, those containing dead‐in‐shell embryos and those with desiccated ...
J. R. Baker, R. Baker
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Furosemide decreases eggshell thickness and inhibits 45Ca2+ uptake by a subcellular fraction of eggshell gland mucosa of the domestic fowl

Comparative Biochemistry and Physiology Part C: Comparative Pharmacology, 1992
1. Administration of furosemide to egg-laying domestic fowl (single p.o. dose 100 mg/bird) caused a decrease in the thickness of the shell of eggs laid the next day. 2. Furosemide administration in vivo caused a 37% decrease in the uptake of 45Ca2+ by a subcellular fraction of the eggshell gland mucosa (mainly composed of cell fragments and plasma ...
C E, Lundholm, M, Bartonek
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