GLEANIKGS IN BEE CULTURE 



March, 1922 



and dried over sulphuric acid in a dessica- 

 tor. In addition to this, the air was pumped 

 out of the dessicator once a day, in order to 

 draw off any moisture that escaped from the 

 larval food. In this way it dried very quick- 

 ly, yet without any heat or chance of fer- 

 menting. Instead of being white or gray- 

 ish white in color, it was now light amber 

 in color, hard and brittle. The color was 

 not due to chemical change. The solids, 

 had merely been concentrated. 



I was unable to collect much more than a 

 water glass full in dry condition the first 

 summer, altho a lot of queen-cells were 

 started in order to secure enough of the 

 material to make the analysis worth while. 



In the spring of 1916 I wrote 180 letters 

 to as many beekeepers in every nook and 

 corner of Wisconsin. I asked them to save 

 all the queen-cells that they possibly could, 

 removing the larvae, and sending the cells 

 to me as soon as possible, after removing 

 from the hives. About 30 beekeepers re- 

 sponded, and with what I received from 

 them, together with that secured from the 

 University queen-rearing yard, I had suc- 

 ceeded by fall (1916) in obtaining the larval 

 food from about ten thousand queen-cells. 

 The beauty of it was that it came from 

 many sources, and any analysis conducted 

 with it would be a good average of larval 

 food as it exists. 



In carrying out the chemical analysis, I 

 had the co-operation of another student, 

 E. G. Gross, who performed the analytical 

 work. 



The elementary analysis that had to be 

 conducted, checks very well with the results 

 of Dr. Adolph V. Planta, as obtained be- 

 tween 1885 and 1888. Dr. E. F. Phillips in 

 his book, "Beekeeping," doubts the results 

 of Dr. Planta, but we found them to be cor- 

 rect. However, his analysis is only an ele- 

 mentary one. No compounds were isolated, 

 therefore, no conclusion can be drawn as to 

 wherein lies the nutritive value of larval 

 food. 



The first procedure was to determine the 

 different groups of organic and inorganic 

 compounds, viz.: protein, fat, sugars and ash 



(mineral matter). The following results 

 were obtained: 



COMPOSITION OF LARVAL FOOD IN AIR- 

 DRIED CONDITION. 



Moisture after drying at 100°C 24.15% 



Total nitrogen 4.58% 



Total protein (factor 6.25) 30.62% 



Total phosphorus 67% 



Total sulphur 38% 



Total ash 2.34% 



Total sugars 14.05% 



Total dextrose 11.70% 



Total sucrose 3.35% 



Total ether extract 15.22% 



Iodine number of ether extract 12.51% 



At least a dozen tables would be neces- 

 sary to give all of the data that were se- 

 cured in the analysis of the larval food, but 

 only a mere summary of all of these tables 

 and data can be given here. 



The protein consisted of 76.37% of non- 

 basal nitrogen, of which 59.49% was amino 

 nitrogen, 5.16% ammonia nitrogen, and 

 3.23% melanin nitrogen. The basal nitro- 

 gen constituted 14.23% of which 9.51% was 

 basal amino nitrogen, 1.74% histidine nitro- 

 gen, 4.41% lysine nitrogen, 3.28% cystine 

 nitrogen and 4.77% arginine nitrogen. The 

 material was fairly rich in basic nitrogen, 

 and unusually rich in cystine. It also con- 

 tained trytophane and tryrosine. 



Boiling it all down, we have three con- 

 stitutents to consider, viz., proteins, sugars, 

 and fats. These three constituents of larval 

 food determine its nutritive value. Prob- 

 ably the greatest factor of all is the high 

 protein content. Few foods are so high in 

 protein; and the form in which the protein 

 exists, would allow us to conclude that the 

 great nutritive value of larval food lies in 

 its high protein content. The high sugar 

 content gives to the larva a readily avail- 

 able source of energy. It should be noted 

 tliat the sugars exist chiefly as dextrose. 

 The ash content is not abnormally high, 

 which brushes aside the belief that has ex- 

 isted in the past, that bees need a large 

 quantity of mineral matter in feeding their 

 young. It is clear that the protein and fat 

 are derivd from the pollen, and sugars from 

 lioney. The ash is derived probably jointly 

 from pollen and honey. However, it is fair 

 to suppose that a portion of the sugars is 



View of the apiary at University of Wisconsin, where Mr. Acjipler made his exijerinients on royal jelly. 



