ABSTRACT
Glycogen accumulation in the myocardium during incubation at 40 ·0°C. has been investigated. Normal temperature incubation (37 · 5° C.) was used for the Control Group. Specimens in Experimental Group I were incubated at 40 ·0°C. during the 3rd through the 6th day of incubation while the specimens in Experimental Group II were incubated continuously at a temperature of 40 ·0°C.
The Anthrone method of glycogen determination was employed. The glycogen from the heart was studied in three to thirteen embryos from the Control Group and each Experimental Group for each of the following days of incubation : 6, 8, 10, 11 and 12.
The mean per cent, glycogen, standard error and standard deviation from the mean per cent glycogen was determined for each group studied on the days of incubation indicated above. The ‘t’ test for the comparison of two groups was applied. The following results were obtained :
There was no significant difference in the per cent, myocardial glycogen in the embryos from the groups at 6 days incubation.
The Experimental Group I showed a significant decrease (1 per cent, level of significance) in myocardial glycogen from the Control Group at 11 and 12 days incubation.
The myocardial glycogen in Experimental Group II was significantly lower (1 per cent, level of significance) than that of Experimental Group I at 10 days incubation.
The application of elevated temperature (40 ·0° C.) sufficient to cause visceral enlargement and coelosomia, whether it is applied during the 3rd through the 6th day of incubation or continuously in the incubation of the chick embryo, results in a significant decrease in the accumulation of myocardial glycogen.
