Coefficients of determination between 0.60 and 0.74 were sufficient in 

 routine estimates of hematological status. 



Coefficients of determination sufficient for research purposes were 

 found in the correlation of microhematocrit with hemoglobin concentration 

 for white perch and spot (Table B-1). The correlation of microhematocrit 

 with red blood cell count in hogchokers was of no predictive value in 

 parametric estimates for research purposes (r^ = 0.7451). The microhema- 

 tocrit with hemoglobin concentration correlation in striped bass was Suf- 

 ficient for routine hematological work (r^ = 0.7011). 



The correlation of microhematocrit with red blood cell count and the 

 correlation of hemoglobin concentration with red blood cell count, did not 

 account for sufficient variance to use regression methods in predictive 

 estimates of hematological parameters in perch, spot, striped bass, and 

 menhaden (Table B-1). 



The three hematological parameters are closely related in a physical 

 and biological sense. Microhematocrit measures the percent volume of red 

 blood cells in a sample. Red blood cells in most vertebrates transport 

 the respiratory pigment, hemoglobin. Therefore, the predictive correlations 

 between microhematocrit and hemoglobin concentration in white perch and 

 spot are largely dependent on the quantity of red blood cells present. 

 To establish whether the correlation of microhematocrit and hemoglobin con- 

 centration was significant and independent of red blood cell count, partial 

 correlation coefficients were determined for microhematocrit-hemoglobin 

 concentration-red blood cell count interrelationships. This statistic 

 estimated the correlation of two variables, microhematocrit and hemoglobin 

 concentration; the red blood cell count variable was held constant. 



Partial correlation coefficients were determined for all species in 

 which the three variables were studied (Table B-2). Partial correlation 

 coefficients showed the relationship of microhematocrit and hemoglobin 

 concentration in white perch and spot statistically independent of red 

 blood cell count (Table B-2). 



The relationships established for these species have significant value. 

 The ability to estimate blood parameters in estuarine fish from a simply 

 determined value, such as microhematocrit, may facilitate physiological 

 studies of estuarine fish in the field and in the laboratory. These hema- 

 tological studies can estimate stress responses in fish (Hesser, 1960; 

 Summerfelt, Lewis, and Ulrich 1967). Physiological and hematological 

 field studies could increase the value of onsite environmental disturbance 

 studies. Estimates of sublethal effects of various pollutants on fish 

 populations should prove useful to estuarine biologists. 



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