Causes of variation in the haemoglobin content of Daphnia (Crustacea: Cladocera) in nature

Abstract

Summary. The haemoglobin content of Daphnia in the ponds studied was found to vary inversely with the oxygen concentration in the water, but not to be proportional to the iron content of the water. In six ponds Daphnia was found to have a greater haemoglobin concentration in winter than in summer, whereas in one body of water the haemoglobin concentration was greater in summer than in winter. Haemoglobin may be more concentrated in the blood of one pond‐dwelling species of Daphnia than of another species in the same water.

Hemoglobin concentration in Daphnia (D. galeata–hyalina) from the epilimnion is related to the state of nutrition and the degree of protein homeostasis

“…4C,D). A previous study (Chandler 1954) 2004b). To withstand hypoxia and to inhabit oxygen-poor water layers, Daphnia enhances the synthesis of Hb macromolecules of higher oxygen affinity (Kobayashi and Hoshi 1982;Kobayashi et al 1988;Sell 1998).…”

Hemoglobin concentration in Daphnia (D. galeata‐hyalina) from the epilimnion is related to the state of nutrition and the degree of protein homeostasis

“…4C,D). A previous study (Chandler 1954) reported increasing Hb concentrations in Daphnia (D. magna, Daphnia pulex, Daphnia obtusa) sampled during the last months of the year, which was discussed in context of environmental hypoxia. Actually, Hb is an essential part of the oxygen transport system of Daphnia (Pirow et al 2001; Paul et al ).…”

What was Glaucoma Called before the 20th Century?

“…The English surgeon George Chandler (d. 1823) summarized Platner’s description 69 : “a hard eye resisting to the finger…[with] a certain sensation of weight and pain in it;…within the eye hath the colour of the sea: …the pupil is dilated,…because both the vitreous humour and the retina are pressed by the lens, which is much swelled, the faculty of seeing entirely perishes…; they call this disease a glaucoma.” …”