8 



BULLETIN 391^ V. S. DEPARTMENT OF AGRICULTURE. 



The number of bacteria in the eggs which contained organisms 

 varied widely for the three groups, as can be seen from Part II of 

 Table III. This is what would be expected, because after bacteria 

 have once entered an egg the number present depends upon condi- 

 tions favoring growth, such as warm temperatures. 



These data substantiate the popular belief that organisms may 

 penetrate eggs with sound shells if unfavorable conditions, such as 

 filth, moisture, and high temperatures, are incurred during marketing, 

 but not to such an extent as they penetrate cracked shells. The 

 chance of contamination is greater in the case of leaking eggs, owing 

 to exposure of the contents. 



<5./'% 



^o.^% 



Fig. 2. — Relation of bacteria to soundness of shell. Total bar = per cent containing 

 bactef la. Black portion of bar = per cent containing organisms fermenting lactose 

 bile. 



Table III. — Relation of bacteria in eggs to soundness of shell. 



I. EGGS CONTAINING BACTERIA. 



Description of shell. 



Number 

 examined. 



Number 

 positive. 



Per cent 

 positive. 



Whole 



11,167 



' 784 



101 



101 

 146 

 31 



8.7 





18.6 



Leaking . - ■ 



30.7 









Total. . 



2,052 



278 



13.5 







1 29 blind checks, 2 of which (6.9 per cent) contained bacteria, are included in this number. 

 IT. VARIATION IN BACTERIAL CONTENT OF EGGS CONTAINING BACTERIA. 





Number of bacteria per cc. 





Description of shell. 



101 to 1,000. 



1,001 to 

 10,000. 



10,001 to 

 50,000. 



50,001 to 

 100,000. 



100,001 to 

 500,000. 



Over 

 500,000. 



Total 

 num- 

 ber of 





Num- 

 ber 

 eggs. 



Per 



cent. 



Num- 

 ber 

 eggs. 



Per 



cent. 



Num- 

 ber 

 eggs. 



Per 



cent. 



Num- 

 ber 

 eggs. 



Per 

 cent. 



Num- 

 ber 

 eggs. 



Per 

 cent. 



Num- 

 ber 

 eggs. 



Per 



cent. 



eggs. 



Whole 



33 

 35 



8 



32.7 

 24.0 

 25.8 



15 



24 



6 



14.8 

 16.3 

 19.4 



8 

 25 

 3 



7.9 

 17.1 

 9.7 



9 



10 

 1 



8.9 

 6.8 

 3.2 



7 

 20 

 5 



6.9 

 13.7 

 16.1 



29 



32 



8 



28.7 

 21.9 

 25.8 



101 



Cracked 



146 



Leaking 



31 







Total 



76 



27.4 



45 



16.2 



36 



12.9 



20 



7.2 



32 



11.5 



69 



24.8 



278 







III. EGGS CONTAINING ORGANISMS FERMENTING LACTOSE BILE. 



Description of shell. 



Number 

 examined. 



Number 

 positive. 



Per cent 

 positive. 



Whole ■ . . . 



1,132 



751 

 97 



6 

 32 



8 



1.4 



Cracked 



4.3 



Leaking ... 



8.2 







Total 



1,980 



56 



2.8 







