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2篇 您的检索式:作者名="R.Robbins"
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1Latitudinal and seasonal variation in reproductive effort of the eastern fence lizard (Sceloporus undulatus)显示文摘Geographic variation in life-history traits among populations of wide-ranging species is influenced by both spa­tial and temporal aspects of the environment. Rarely, however, are the effects of both aspects examined concur­rently. We collected gravid female lizards (Sceloporus undulatus) from northern (Indiana), central (Mississippi) and southern (Florida) populations, spanning nearly the full latitudinal range of the species, to examine among-population differences in strategies of reproductive energy allocation. Adult females from the southern popula­tion were smaller, and produced fewer and smaller eggs in their first clutches than did females from the more northern populations. Southern females were more likely to produce a second clutch, and second clutches were smaller than first clutches for females from the 2 northern populations. Together these trends eliminated popu­lation differences in overall reproductive output after accounting for body size. The trend for greater reproduc­tive energy to be allocated to first clutches at higher latitudes, and to later clutches at lower latitudes is corrobo­rated by published data from field studies on multiple populations. Distributing reproductive effort by producing more clutches of smaller eggs may be an adaptive response to the long season available for egg incubation and lizard activity in sub-tropical southern environments. In contrast, allocating greater resources to early reproduc­tion may enhance maternal fitness in the relatively short activity seasons that characterize more northern sites.Weiguo DU Travis R.ROBBINS Daniel A.WARNER Tracy LANGKILDE Richard SHINE 2014Integrative Zoology2014,9,3:1
2监测俄克拉荷马州发病猪场外不同距离处的空气样本中猪流行性腹泻病毒显示文摘美国首次发生猪流行性腹泻(PorcineEpidemicDiarrhea,PED)是在2013年。因会引起断奶前仔猪的高死亡率,此病正给猪场带来惨重的经济损失。俄克拉荷马州锅柄状地区的许多猪场在短时间内感染了PED,且常见的传染源不详,怀疑经空气(悬浮尘粒)传播。毛慧 Dane Goede R.Robbins L.Dufresne M.Engle A.Rovira Robert Morrison 2014国外畜牧学(猪与禽)2014,34,2:0
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