Effects of Phos-Chek G75-F and Silv-Ex on Developing Northern Bobwhite Quail ( Colinus virginianus )

Abstract

Eggs of nesting birds situated in peripheral areas serving as fire breaks are at risk of being sprayed with fire control chemicals. Acute toxicity tests were conducted by immersing northern bobwhite quail eggs for 10 s in different water-based concentrations of Silv-Ex(R) (SE), a foam-suppressant chemical, and Phos-Chek(R) G75-F (PC), a fire retardant chemical, on day 4 or day 11 of incubation. An attempt was made to relate the treatment concentrations to the actual field application levels. Mortality appeared higher in most groups exposed on day 11 than on day 4, suggesting that on day 11 the extensive chorioallantoic vascular network permitted greater uptake of chemical. Only 24-60% of the embryos survived to hatch at exposure concentrations of 202, 269, and 454 g/L PC when treated on incubation day 11. At higher concentrations including 681956, and 1211 g/L PC, the compound did not completely dissolve in water and clumped on eggshells, resulting in greater hatching success. Exposures to SE at 100 g/L on incubation day 11 did not significantly affect hatching success of embryos but did significantly reduce the percent hematocrit in blood compared with controls. Incubation day 11 exposure to 202 and 1211 g/L PC led to a significant increase in plasma aspartate aminotransferase, and day 4 exposure to 1211 g/L PC resulted in a significant increase in alanine aminotransferase. In addition to elevated liver enzymes, these treatments resulted in a decrease in the number of hepatocyte profiles (1211 g/L PC at day 4 and day 11) and an increase in hepatocyte size (202 and 1211 g/L PC at day 11) in hatchlings. A combination of SE and PC was synergistic (202 g/L PC and 50 g/L SE) at day 11 of incubation with respect to decreased hatching success and reduced bone lengths. However, lower concentrations of SE (10 g/L or 30 g/L) combined with 202 g/L of PC appeared antagonistic. This may be due to SE, as a surfactant, altering the ability of PC to penetrate the egg. Our results show fewer adverse effects following exposure to SE than to PC; therefore application of SE may be less harmful to breeding bird populations.

Topical dose delivery in the reptilian egg treatment model

“…For example, obstruction of the pores of the shell and shell membrane could alter oxygen, carbon dioxide, and water exchange that may secondarily affect energy metabolism and, perhaps, thereby alter internal temperatures. Regardless of the biological end point measured, the potential interpretational challenges created by ambiguous dose data also are critical for other experimental systems in which chemicals have been applied to eggs, such as topical application of herbicides or pesticides to avian eggs to simulate exposures arising from agricultural spraying practices [67–83].…”

“…26, 2007 917 pores of the shell and shell membrane could alter oxygen, carbon dioxide, and water exchange that may secondarily affect energy metabolism and, perhaps, thereby alter internal temperatures. Regardless of the biological end point measured, the potential interpretational challenges created by ambiguous dose data also are critical for other experimental systems in which chemicals have been applied to eggs, such as topical application of herbicides or pesticides to avian eggs to simulate exposures arising from agricultural spraying practices [67][68][69][70][71][72][73][74][75][76][77][78][79][80][81][82][83]. The interpretational challenges presented by ambiguous dose assumptions are not unique to in ovo exposures or endocrine mechanisms; however, the challenges may be exacerbated disproportionately in complex experimental system and for complex biological pathways, such as those mediated by the endocrine system.…”

Effects of diethylstilbestrol and ethinylestradiol on gene transcription of very low‐density apolipoprotein II in the liver of Japanese quail, Coturnix japonica

“…An alternative method of exposing fertile eggs to exogenous chemicals is by immersing them for several seconds in an aqueous or alcoholic solution of the test chemicals [14]. This mode of exposure is relevant to the environmental contamination of species in the field, because the spraying of pesticides, insecticides, and fire-control chemicals would be likely to affect the surface of eggshells and the chemicals might pass through the pores in the shell [15].…”

Resolving conflicts in fire management using decision theory: asset‐protection versus biodiversity conservation

“…2004). However, impacts on terrestrial biodiversity are poorly documented, although there is evidence that low‐nutrient adapted plants and some birds are detrimentally affected (Buscemi et al . 2002; Bell et al .…”