Thermal acclimation and seasonal variations of erythrocyte size in the Andean mouse Phyllotis xanthopygus rupestris

详细信息    查看全文

• 作者：Ruiz ; Gricelda ; Rosenmann ; Mario ; Cortes ; Arturo
• 关键词：Phyllotis xanthopygus rupestris ; Blood values ; Erythrocytes ; Seasonal changes ; Thermal acclimation ; Red cell size variation ; Andean rodents ; Acclimatization
• 刊名：Comparative Biochemistry and Physiology, Part A
• 出版年：2004
• 出版时间：December, 2004
• 年：2004
• 卷：139
• 期：4
• 页码：405-409
• 全文大小：101 K

文摘

Seasonal hematological adjustments in small mammals may include changes in the number and size of the red cells or changes in other linked blood parameters. The direction and magnitude of these changes vary in different species. We hypothesized that the observed variations of the red cell adjustments could be directly related to the magnitude of the seasonal temperature differential, and predicted that the annual red cell size variation in rodents from environments with marked seasonal changes would tend to disappear, if the animals were raised under milder and constant environments. To test this idea, we got field blood samples from the Andean species Phyllotis xanthopygus rupestris enduring a winter–summer thermal differential of at least 20 °C. These animals had significantly smaller erythrocytes during the winter. Contrary to our prediction, their offspring born and raised under constant temperature conditions showed a similar trend. Unless the effective environmental cue differed from the one we used, these results favor the idea of a genetically determined annual red cell size variation that occurs independent of thermal acclimation and acclimatization.