Wetlands are often created through wetland mitigation to replace lost natural wetlands, but further evaluation is needed to determine the ability of a created wetland to replace lost wetland functions, especially prov...Wetlands are often created through wetland mitigation to replace lost natural wetlands, but further evaluation is needed to determine the ability of a created wetland to replace lost wetland functions, especially providing wildlife habitat. We used a mesocosm design to compare the water quality between three created wetlands and three natural wetlands in West Virginia, USA and to evaluate how the water quality from the two wetland types were able to support metamorphosis in larval spring peepers (<em>Pseudacris crucifer</em>) and wood frogs (<em>Lithobates sylvaticus</em>) across two years (2014-2015). Responses in metamorphosis rates differed between species and between years. Spring peepers displayed similar metamorphosis rates in the created and natural wetlands in both years of the study. Wood frogs displayed similar metamorphosis rates in created and natural wetlands in 2015, but in 2014 wood frogs reached metamorphosis in less time and at a larger body size in the natural wetlands, suggesting that the wood frogs that developed in the natural wetlands may have higher fitness than those that developed in the created wetlands. Water quality was largely similar between created and natural wetlands, although dissolved oxygen, conductivity, and pH varied between mesocosms and wetlands. Our study suggests that created wetlands may be providing partial mitigation in terms of water quality for amphibian development. We recommend that future monitoring of created wetlands include measures of juvenile amphibian recruitment as well as additional habitat variables to better determine the ability of created wetlands to function as amphibian habitat.展开更多
An acute phase response induced by Gram-negative bacteria can reduce pregnancy rate. Early pregnant ewes were used to monitor effects of lipopolysaccharide (LPS), an endotoxin in the outer cell membrane of Gram-negati...An acute phase response induced by Gram-negative bacteria can reduce pregnancy rate. Early pregnant ewes were used to monitor effects of lipopolysaccharide (LPS), an endotoxin in the outer cell membrane of Gram-negative bacteria, on acute phase/innate immunity response. In Exp. 1, mixed breed ewes were assigned to receive either LPS or LPS and flunixin meglumine, an inhibitor of prostaglandin synthetase, intravenously on day 5 after mating. In Exp. 2, mixed breed ewes were assigned to receive an intravenous injection on day 5 after mating of either saline, LPS, recombinant human tumor necrosis factor (TNF)-α or LPS after pretreatment with dexamethasone. Pregnancy was diagnosed ultrasonographically on d 25, and live births were recorded at parturition. Challenge with LPS induced acute phase responses (fever, mucosal responses, lethargy and increased serum TNF, haptoglobin and?serum amyloid A) and decreased pregnancy rates. Predictably, flunixin meglumine attenuated fever but did not increase pregnancy rate in LPS-treated ewes. Similarly, exogenous TNF alone induced mucosal and serum amyloid A responses but did not affect pregnancy. Pre-treatment with dexamethasone blocked fever and mucosal and lethargic responses and attenuated increases in TNF and haptoglobin but did not ameliorate LPS-induced pregnancy loss. In summary, acute challenge with LPS mimics bacterial-induced pregnancy losses in early pregnant ewes. Although pretreatment with dexamethasone decreased clinical signs and some innate immune responses, neither it nor flunixin meglumine prevented LPS-induced pregnancy loss. That exogenous TNF alone did not promote pregnancy loss indicates that other cytokines also contribute to LPS-induced embryonic loss.展开更多
文摘Wetlands are often created through wetland mitigation to replace lost natural wetlands, but further evaluation is needed to determine the ability of a created wetland to replace lost wetland functions, especially providing wildlife habitat. We used a mesocosm design to compare the water quality between three created wetlands and three natural wetlands in West Virginia, USA and to evaluate how the water quality from the two wetland types were able to support metamorphosis in larval spring peepers (<em>Pseudacris crucifer</em>) and wood frogs (<em>Lithobates sylvaticus</em>) across two years (2014-2015). Responses in metamorphosis rates differed between species and between years. Spring peepers displayed similar metamorphosis rates in the created and natural wetlands in both years of the study. Wood frogs displayed similar metamorphosis rates in created and natural wetlands in 2015, but in 2014 wood frogs reached metamorphosis in less time and at a larger body size in the natural wetlands, suggesting that the wood frogs that developed in the natural wetlands may have higher fitness than those that developed in the created wetlands. Water quality was largely similar between created and natural wetlands, although dissolved oxygen, conductivity, and pH varied between mesocosms and wetlands. Our study suggests that created wetlands may be providing partial mitigation in terms of water quality for amphibian development. We recommend that future monitoring of created wetlands include measures of juvenile amphibian recruitment as well as additional habitat variables to better determine the ability of created wetlands to function as amphibian habitat.
文摘An acute phase response induced by Gram-negative bacteria can reduce pregnancy rate. Early pregnant ewes were used to monitor effects of lipopolysaccharide (LPS), an endotoxin in the outer cell membrane of Gram-negative bacteria, on acute phase/innate immunity response. In Exp. 1, mixed breed ewes were assigned to receive either LPS or LPS and flunixin meglumine, an inhibitor of prostaglandin synthetase, intravenously on day 5 after mating. In Exp. 2, mixed breed ewes were assigned to receive an intravenous injection on day 5 after mating of either saline, LPS, recombinant human tumor necrosis factor (TNF)-α or LPS after pretreatment with dexamethasone. Pregnancy was diagnosed ultrasonographically on d 25, and live births were recorded at parturition. Challenge with LPS induced acute phase responses (fever, mucosal responses, lethargy and increased serum TNF, haptoglobin and?serum amyloid A) and decreased pregnancy rates. Predictably, flunixin meglumine attenuated fever but did not increase pregnancy rate in LPS-treated ewes. Similarly, exogenous TNF alone induced mucosal and serum amyloid A responses but did not affect pregnancy. Pre-treatment with dexamethasone blocked fever and mucosal and lethargic responses and attenuated increases in TNF and haptoglobin but did not ameliorate LPS-induced pregnancy loss. In summary, acute challenge with LPS mimics bacterial-induced pregnancy losses in early pregnant ewes. Although pretreatment with dexamethasone decreased clinical signs and some innate immune responses, neither it nor flunixin meglumine prevented LPS-induced pregnancy loss. That exogenous TNF alone did not promote pregnancy loss indicates that other cytokines also contribute to LPS-induced embryonic loss.
