ANIMAL PKODUCTION. 571 



of marketing, eggs in shell undergo a variety of changes referable, almost ex- 

 clusively, to the mode of handling. From former investigations (E. S. 11.. 22, 

 p. 762) there was found an average of 2 organisms per gram in the white and 

 6 per gram in the yolk of perfectly fresh eggs when the incubation temperature 

 was 37° C, and 7 organisms per gram in the white and 9 per gram in the yolk 

 when the incubation was at 20°. The character of the organisms present was 

 widely diversified. Bacillus coU is practically never present. As regards 

 chemical composition of fresh eggs, whole eggs gave an average percentage of 

 ammoniacal nitrogen of 0.0013. The moisture content is thought to be indi- 

 cative of the egg's resistance to decay. In August and September, when the 

 quality of the eggs is lowest, the maximum quantity of water is found in both 

 white and yolk. In the early spring when eggs are of highest quality the water 

 content is lowest, and in the cool days of autumn it occupies a medium position. 

 An examination of what are termed "market-fresh " eggs showed that bac- 

 terially these eggs do not differ from strictly fresh eggs. 



A study made of the relation between bacterial multiplication and chemical 

 changes indicates that " for certain substances, at least, the number of or- 

 ganisms mus't approach the 100,000,000 per gram mark before the analytical 

 methods for the detection of substances indicative of bacterial life can be 

 applied satisfactorily." 



Summarizing the bacteriological results of Individual eggs opened aseptically 

 in the laboratory, it was found that the greatest percentage of second-grade 

 food eggs examined, the medium stale eggs, hatch-spot eggs, heavy rollers, 

 dirty eggs, cracked eggs, and eggs with yolk partially mixed with albumin 

 contained less than 1,000 bacteria per gram. B. coli was not present in the 

 whole-shelled second-grade eggs and in only 5.9 per cent of the cracked-shelled 

 eggs. In 26.5 per cent of the eggs with adherent yolks, 50 per cent of the eggs 

 with dead embryos, 75.9 per cent of the moldy eggs, 06.7 per cent of the white 

 rots, and 100 per cent of the black rots, over 1,000 organisms per gram were to 

 be found. With the exception of the white and black rots, B. coli was present 

 in but few of the eggs. 



Conclusions reached from bacteriological and chemical examinations of com- 

 posite sample of eggs oi^ened commercially in the packing house are as follows : 

 " The samples of July and August firsts contained very few organisms, and in 

 many cases no bacteria of the B. coli group. The majority of the samples of 

 clean-shelled seconds had a comparatively low bacterial content, only 8.3 per 

 cent of them containing over 1,000,000 organisms per gram. The number of 

 B. coli varied in different specimens from none to 100,000 per gram. The per- 

 centage of bacterial counts over 1,000,000 per gram in samples of dirties, checks, 

 and eggs with yolk partially mixed with albumin was 16.6, 18.8, and 20 per 

 cent, respectively. No greater number of B. coli was found in these samples 

 than in samples of seconds. 



"The samples of blood rings contained comparatively few organisms. The 

 large blood rings in most instances showed more infection than did the small 

 rings. Most of the specimens contained less than 10 B. coli per gram. The 

 amount of protein decomposition as shown by the ammoniacal nitrogen in the 

 preceding six types of eggs was greater, as would be expected, than that found 

 in strictly fresh eggs, but was no greater than that found in some grocery eggs. 

 Although a cracked or dirty shell may be a factor in facilitating infection and 

 subsequent decomposition, the data obtained show that checks and dirties in 

 the producing section are as well preserved as the clean whole-shelled seconds 

 or the July and August firsts. The eggs constituting the samples of July and 

 August firsts, seconds, dirties, and checks would be used without compunction 

 by the housewife, baker, or confectioner. 



