1882 



Van Winkle, Webb. 19 68. 



The effects of additives on the pumping rate of Mercenaria mercenaria. 

 Proc. Natl. Shellf. Assn. 58: 9-10 "(abstract). 



Effects of additives on pumping of Mercenaria mercenaria were measured. 

 Additives included: simple organic compounds (glucose and glycine) ; 

 hormones (acetylcholine, adrenalin, and serotonin); and gonad extracts 

 (male and female Mercenaria and Mytilus) . The simple organic compounds, 

 and adrenalin and serotonin occasionally, stimulated pumping. Acetylcholine 

 inhibited pumping at 10 - 7-10~3m. Mercenaria gonad extracts stimulated 

 pumping and spawning. - D.L. 



1883 



Van Winkle, Webster, Jr. 1968. 



The effects of season, temperature, and salinity on the oxygen consumption 

 of bivalve gill tissue. Comp. Biochem. Physiol. 26(1): 69-80. 



Oxygen consumption of gill tissue from Mercenaria mercenaria and 3 other 

 species was measured at salinities of 5, 10, 15, 20, 25, and 30°/ oo and 

 temperatures of 10, 18, and 26°C, winter and summer. At any salinity level, 

 oxygen consumption of hard clam tissue increased with temp. At any temp 

 level oxygen consumption decreased with increasing salinity. Clams 

 collected in summer consumed more oxygen at any particular temp level than 

 those collected in winter. Summer clams also consumed more oxygen at any 

 particular salinity level. - J.L.M. . 



1884 



Van Winkle, Webster. 1972. 



Ciliary activity and oxygen consumption of excised bivalve gill tissue. 

 Comp. Biochem. Physiol. 42A(2): 473-485. 



Ciliary activity of gill tissue from low- and high-salinity acclimated 

 Mercenaria mercenaria, American oyster and 2 species of mussel was measured 

 at various salinities. For each species there was initial inhibition of 

 activity at experimental salinities differing appreciably from acclimation 

 salinity. If the difference between experimental and acclimation salinity 

 was not too great, inhibition was followed by recovery. Recovery time- 

 experimental salinity response surfaces were shifted toward lower salinities 

 for low-salinity acclimated oyster and mussels, but not for hard clam, 

 compared to high-salinity acclimated groups. At low as compared to high 

 salinities, ciliary activity decreases, whereas oxygen consumption increases 

 or remains approximately constant. - modified author's abstract - J.L.M. 



1885 



Van Winkle, Webster. 1975. 



Problems in establishing the relationship between pumping rate and oxygen 

 consumption rate in the hard clam, Mercenaria mercenaria. Comp. Biochem. 

 Physiol. 50A(4): 657-660. 



The literature contains conflicting conclusions on the relationship. Some 

 authors have concluded that oxygen removal by hard clam is a consistent 

 function of water transport, and that water transport may be regulated at 

 least partially by oxygen requirements. Another author suggested that the 

 cause-effect relationship was the reverse, and that increased oxygen 

 consumption rate followed from an increase in pumping rate, stating that 

 pumping is work accomplished by energy supplied by respiratory processes. 

 The author concluded that the question has not been settled, and that more 

 direct physiological evidence is needed, such as simultaneous measurements 

 of pumping rate, external oxygen levels, and blood oxygen levels, to 

 determine whether pumping rate of hard clam is dependent upon oxygen 

 requirements. - J.L.M. 



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