174 EXPERIMENT STATION EECOED. [Vol. 35 



The following eggs should be discarded during grading : Black, white, mixed, 

 and sour rots, eggs with green whites, eggs with stuck yollvs, musty eggs, uioldy 

 eggs, " blood rings," eggs containing diffuse blood, and eggs with abnormal odor. 

 An appendix gives details of the conditions observed in the various establish- 

 ments studied. 



The bacterial infection of fresh eggs, P. B. Hadley and Dokothy W. Cald- 

 well {Rhode Island Sta. Bid. 164 U916), pp. 3-70, figs. 3).— After a historical 

 resume of investigations on the bacterial infection of eggs this bulletin takes 

 up a report of experiments begun in 1911. The results of the study are sum- 

 marized as follows : 



Of 2,520 fresh eggs examined by the indirect method 8.7 per cent showed 

 bacterial infection in the yolk. None of the 111 whites examined showed in- 

 fection, while the yolks of the same eggs gave a percentage slightly less (4.5 

 per cent) than the average for the series (7.7). The percentage of infection 

 obtained for individual hens per year varied between 2.8 and 15, the average 

 being 9. No hen laid all sterile eggs during any full year. No correlation was 

 observed between percentage of infection and hatchability, or between the 

 percentage of infection and the fecundity, age of the hens, or season of the 

 year. The percentage of infection for infertile and for fertilized eggs was 

 essentially the same. The nature of the infecting organisms occurring in the 

 eggs was briefly studied, and 40 bacterial types were obtained, including 11 

 cocci, 28 rods, and 1 spirillum. 



It is concluded that the most probable source of primary egg infection is the 

 ovaries of the fowl, which become infected by bacteria escaping through the 

 intestinal wall into the portal circulation. The nature of the bacterial species 

 occurring in the primary infection makes clear the fact that primary infection 

 plays no rule in bringing about the decomposition of eggs. For the factors de- 

 termining this result we must look mainly to the secondary infections. The 

 nature and extent of the normal primary infection stands in no causal relation 

 to embryo mortality in incubating eggs, and losses in " dead-in-sliell " eggs can 

 not be explained on these grounds. 



A bibliography of literature cited is given. 



DAIRY FAEMING— DAIEYING. 



The value of rav/, steamed, and ensiled raw and steamed potatoes for milk 

 production, W. Voltz and W. Dietrich (Landiv. JaJirb., 48 {lOJS), No. 4. PP- 

 535-56!)). — Potatoes prepared in various ways were tested as a supplement to 

 a l)asal ration of meadow hay, oat straw, and brewers' grains. 



Steamed potatoes and ensiled raw potatoes had little effect on the milk yield, 

 but material gains were obtained from the feeding of ensiled steamed potatoes. 

 The highest milk yield was obtained from raw potatoes and was 2.5 times the 

 yield from steamed potatoes. 



With all four preparations the fat and dry-matter contents of the milk were 

 increased, (he fat content being especially high with the raw ensiled and the 

 steamed potatoes. The greater quantity of protein and fat-free dry matter 

 were obtained from raw potatoes, followed by ensiled steamed and steamed po- 

 tatoes. 



Mangolds or swede turnips for dairy cows, J. J. Dunne (Jour. Bd. Agr. 

 [London^, 23 {1916), No. 1, pp. 58-65).— Comparisons were made at the Danish 

 State Experimental Laboratory of the feeding value of swede turnips and 

 mangolds for dairy cows. The average daily milk yield of the mangold-fed 

 cows was .30.73 lbs. and for the turnip-fed cows, 31.46 lbs., while the fat per- 

 centages were 3.06 and 3.01, re.spectively. Little or no difference in the nutritive 



