244 MASS. EXPERIMENT STATION BULLETIN 230 



Average Niiral)er of Times Bred. 



Year "Bone Meal" Group. "No Bone Meal" Group. 



1922 1.60 1.67 



1923 2.25 2.67 



1924 2.67 2.57 



1925 1.60 1.50 



Abortions and Retained Afterbirths. 



There have been three cases of abortion and one premature birth in the herd 

 since the commencement of the experiment. Two of the abortions were in the 

 "bone meal" group, the other one and the premature birth were in the "no 

 bone meal" group. Two of the abortions were caused by accidents and it is 

 doubtful if the other two were due to the effect of the experiment. There 

 have been six cases of retained afterbirth, of which four have been in the "ho 

 bone meal" group. Tliis fact may be of some significance, or it may be mere 

 chance. 



Condition of the Calves at Birth and Subsequently. 



All calves dropped during the course of the experiment have either been 

 raised to maturity or kept a sufficiently long time to enable us to form an 

 accurate opinion as to their constitutional vigor. The following table suni- 

 niarizes the records. 



The only result of any significance here is the somewhat higher number of 

 delicate calves from the "no bone meal" cows. Proportionately the difference 

 between the groups in this respect is not so great as a first glance at the 

 figures seems to show, the ratio being roughly 3 to 2 instead of 5 to 2. Also 

 the delicate calves have with one or two exceptions been from Jersey cows, so 

 that it is probable that breed characteristics have liad more influence than 

 has the experimental treatment. 



