30 BULLETIN 51, U. S. DEPARTMENT OF AGRICULTURE. 



Table 10. — White rots (individual eggs). 



Sample 



Date of 

 examination. 



Total number of bacteria 

 per gram on plain agar 

 incubated at— 



Number 

 of gas- 

 produc- 

 ing bac- 

 teria per 

 gram in 

 lactose 

 bUe. 



Description of sample. 



No; 



20° C. 



37° C. 



3006-2 



Dec. 12,1910 

 do 



110,000.000 



15.000.000 



80,000,000 



295 



3,300,000 



(') 







0) 



120,000 

 



0) 

 270,000,000 



ISO 





Pale yellow contents. 



3006-3 





3012-4 

 275 

 495 

 496 

 497 

 498 

 499 

 500 

 4070 



4110 



Jan. 14,1911 

 July 3. 1911 

 Aug. 10,1911 



do 



do 



do 



do 



do...... 



Sept. 5,1911 



Nov. 1, 1911 





 5,500.000 

 (') 







(') 



120.000 

 



0) 



180,000,000 

 160 









 10,000+ 





 10,000+ 











10,000+ 



100+ 







Clean shell; marked shrinkage: mov- 

 able air cell. 



Shell slightly dirty but fresh looking; 

 stale odor; marked shrinkage; movar 

 ble air cell. 



1 Innumerable; dilution, 1: 10,000. 



The bacterial content in 8 out of the 12 i,s very high. Two of the 

 eggs were sterile and two of them showed a low count. B. coli 

 were looked for 9 times out of the 12 and found 4 times. 



The high bacterial content of these white rots is quite in accord 

 with their appearance. 'Wh.j there should occasionally be a white 

 rot with a low count, as in Samples 3012-4, 498, and 4110, or even 

 a sterile white rot,^ as in Samples 496 and 499, remains to be ex- 

 plained. Since these white rots seem to be the logical sequence of 

 the mixed egg^ they might easily parallel the latter in their bacterial 

 content, 



EGGS HAVING YOLK ADHERENT TO SHELL (SPOT ROTS). 



The " spot rots " of commerce are eggs in which the yolk has 

 become adherent to one or both of the shell membranes and, per- 

 haps, to the shell itself by means of the membranes. Wlien held 

 before the candle, therefore, the yolk is seen as a distorted, deeply 

 colored mass pressed against some part of the shell (see PI, IV). 

 As the egg ages in temperatures which are lower than those causing 

 incubation phenomena, the yolk of either the fertile or the infertile 

 ^gg settles. If the Qgg is not moved the yolk finally adheres to the 

 membrane against which it rests and it becomes a " spot rot " or, as 

 termed in this report, an egg with the yolk adherent to the shell. 

 If the Q^gg is infertile and ages at such temperatures as prevail in 

 summer time, the yolk frequently rises, presses against the air cell, 

 and finally sticks there. Forty-two such eggs are listed in Table 11. 

 T^^len held before the candle some show no marked characteristics 

 except the adherent yolk. Others show distinct evidences of incuba- 

 tion, general deterioration, cracked shells, etc. 



1 In a dilution of 1 to 10. 



