10 Poultry Bulletin 



Analyzing the two tables and comparing the totals, we find that the 

 percent of hatch in live, healthy, chicks based on all eggs set was in the 

 case of the yeast fed pens 54.5 while in the case of the non-yeast fed pens 

 it was 29.3. On the basis of all eggs set this is an increase of 25.2% in the 

 hatch of vigorous, healthy chicks from the yeast fed pens over the non- 

 yeast fed pens. 



These results are certainly very marked in the increased fertility and 

 hatchability which yeast fed birds impart to their eggs. The reasons why 

 yeast accomplishes this result have not been scientifically determined. It 

 is a known fact however, that yeast is the richest in vitamine B of any 

 known feeding substance. The rations fed to the yeast birds were ex- 

 tremely rich in active live growing yeast plants which means that there 

 must have been added to the ration of the yeast fed birds greatly in- 

 creased quantities of vitamine B. 



During the progress of the fall experiment careful laboratory tests were 

 made of the fermented mash and it was found that when mixed and fer- 

 mented as outlined above the actual increase in yeast plants as well as 

 the increased weight of yeast in the mixture was about ten times. Which 

 means that where Yi°/o OI dry feed yeast was added, after 20 hours of 

 fermentation, there was approximately 5% of this product present. 



TABLE NO. 4 



YEAST COUNT ON MASH FERMENTED AT 38° C. 



During the progress of the experiment, in fact from the first of August, 

 both lots of birds had been confined to their laying quarters and had re- 

 ceived in the nature of green feed only very limited quantities of mangel 

 beets. There had been no opportunity for either lot of birds to secure 

 any considerable amount of vitamine B from tender leafy plant growth 

 which they would have been able to do if they had been running out-of- 

 doors. Conditions, so far as the birds were concerned, were similar to 

 midwinter or early spring breeding conditions. 



Throughout the progress of the fall experiment the birds in the yeast 

 fed pens seemed to show a decided increase in appetite which was prob- 

 ably due to the increased palatability of the yeast fermented mash. This 

 increased palatability could not but help having a marked influence in 

 increasing the general efficiency of the rations fed. The slight amount of 

 alcohol present in the yeast fermented mash, no doubt, had a marked 

 stimulating effect upon the breeders, males and females alike, which in all 

 probability is a contributing factor to the very marked results secured. 



