Effects of low-oxygen conditions on embryo growth in the painted turtle,Chrysemys picta  

作　　者：Gerardo A.CORDERO Matthew L.KARNATZ Jon C.SVENDSEN Eric J.GANGLOFF 

机构地区：[1]Department of Ecology,Evolution,and Organismal Biology,Iowa State University,Ames,Iowa,USA [2]Technical University of Denmark,National Institute of Aquatic Resources,Freshwater Fisheries,Silkeborg,Denmark [3]Interdisciplinary Centre of Marine and Environmental Research,University of Porto,Porto,Portugal

出　　处：《Integrative Zoology》2017年第2期148-156,共9页整合动物学（英文版）

基　　金：funded in part by graduate student research awards from the ISU-EEOB and NSF grant DEB-1242510(to F.Janzen);J.C.Svendsen was sup­ported by grant SFRH/BPD/89473/2012 from the Foun­dation for Science and Technology in Portugal.

摘　　要：Low-oxygen conditions(hypoxia;<21%O_(2))are considered unfavorable for growth;yet,embryos of many vertebrate taxa develop successfully in hypoxic subterranean environments.Although enhanced tolerance to hypoxia has been demonstrated in adult reptiles,such as in the painted turtle(Chrysemys picta),its effects on sensitive embryo life stages warrant attention.We tested the hypothesis that short-term hypoxia negatively affects growth during day 40 of development in C.picta,when O_(2) demands are highest in embryos.A brief,but severe,hypoxic event(5%O_(2) for 0.5 h)moderately affected embryo growth,causing a 13%reduction in mass(relative to a normoxic control).The same condition had no effect during day 27;instead,a nearly anoxic event(1%O_(2) for 72 h)caused a 5%mass reduction.All embryos survived the egg incubation period.Our study supports the assumption that reptilian embryos are resilient to intermittently low O_(2) in subterranean nests.Further work is needed to ascertain responses to suboptimal O_(2) levels while undergoing dynamic changes in developmental physiology.

关 键 词：embryo metabolism embryo respiration growth rate nest environment oxygen consumption rate 

分 类 号：R36[医药卫生—病理学]