834 



Hidu, Herbert, and Haskell S. Tubiash. 1966. 



A bacterial basis for the growth of antibiotic- treated bivalve larvae. Proc. 

 Natl. Shellf. Assn. 54: 25-39. 



Addition of 100 to 300 parts per million of the antibiotic "Combistrep" 

 (dihydrostreptomycin-streptomycin sulfates) to hard clam larval cultures 

 increased larval growth more than 10 0% over control cultures. Growth 

 increased 25% in larval cultures fed live flagellates and Combistrep as 

 compared to cultures fed live flagellates but no Combistrep. Addition of 

 Combistrep to filtered UV-treated seawater increases the number of bacteria 

 in proportion to the concentration of Combistrep. In bacteria free larval 

 cultures with Combistrep, larval clam growth did not increase. This suggests 

 that bacterial flora in Combistrep-treated cultures may be utilized by clam 

 larvae as food. - D.L. 



B35 



Hidu, Herbert, and Ravenna Ukeles . 1964. 



Dried unicellular algae as food for larvae of the hard shell clam, Mevcenavia 

 mevcenavia. Proc. Natl. Shellf. Assn. 53: 85-101. 



Three species of unicellular algae preserved by drying can be utilized as 

 food by larvae of hard shell clam, Mevcenavia mevcenavia. The chlorophyte, 

 Dunaliella euchlova, and the chrysophyte, Isochvysis galbana, f reeze-dried, 

 gave clam growth and survival comparable to that obtained when these species 

 were fed at similar rates as live algae. Heat-dried samples of green alga, 

 Scenedesmus obliquus , mass-produced in Japan, also gave good growth and 

 survival of clam larvae. Sulmet (sodium sulfamethazine) increased growth 

 and reduced mortality of clams when used with the dried foods . Agitation 

 of clam cultures proved advantageous when used with dried S. obliquus but 

 gave variable results with the other two species of dried algae. Dried uni- 

 cellular algae under suitable culture conditions possess desirable physical 

 and nutritive properties for an ideal nonliving food for mollusks. If 

 adequate culture techniques are developed, dried algae may find wide appli- 

 cation, as in rearing juvenile clams and oysters. - modified authors' 

 abstract. - D.L. 



336 



Higgins, William J. 1974. 



Intracellular actions of 5 -hydroxy tryptamine on the bivalve myocardium. 

 I. Adenylate and guanylate cyclases. J. Exp. Zool. 190(1): 99-109. 



Effects of the neurotransmitters 5-hydroxytryptamine (5HT) and acetylcholine 

 (ACh) on adenylate and guanylate cyclase activity in ventricles of Mevcenavia 

 mevcenavia and Maovocallista nimbosa were examined. Adenylate cyclase 

 activity and intracellular adenosine cyclic monophosphate (AMP) were 

 increased by 5HT. ACh had no effect. Neither agent altered ventricular 

 guanosine cyclic monophosphate (GMP) significantly. Positive correlation 

 between excitatory action of 5HT and simultaneous increase in intracellular 

 cyclic AMP strongly suggested that this nucleotide mediates 5HT excitation. 

 But classical pharmacological evidence is lacking. Cyclic AMP, dibutyryl 

 cyclic AMP, and phosphodiesterase inhibitors have no effect on mechanical 

 activity of isolated bivalve ventricles. - modified author's abstract - J.L.M. 



337 



Higgins, William J. 1974. 



Cyclic AMP-mediated calcium accumulation by bivalve heart microsomes. Am. 

 Zool. 14 (4) : 1246. 



The nucleotide cyclic AMP is thought to exert intracellular actions by 

 activating cyclic AMP-dependent protein kinases which, in turn, phosphorylate 

 substrate proteins. This kinase was purified from ventricles of Mevcenavia 



233 



