264 



Maine Agricultural Experiment Station. 1919. 



From these results the equations for the prediction of the 

 average butter-fat percentage of the five lactations have been 

 found. These are sdven below. 



Average butter-fat percentage for five lactation yield=1.819-|-.648x 1st lactation 



Average butter-fat percentage for five lactation yield=1.621-f-.688x 2nd lactation 



Average butter-fat percentage for five lactation yield=1.591-|-.685x 3rd lactation 



Average butter-fat percentage for five lactation yield=1.349-)-.740x 4th lactation 



Average butter-fat percentage for five lactation yield=1.406-(-.736x 5th lactation 



The solution of the first equation has been made of the 

 butter-fat percentage at two years to determine the expected 

 butter- fat percentage for the five lactation periods. These re- 

 sults are given in table 5. 



TABLE 5. 



Actual Butter-fat Percentages of Two Year Old Cows and the 

 Expected Five Lactation Butter-fat Percentage. 



Actual 



Two Year Butter-Fat 



Expected Butter-Pat Percentage ■ for 





Percentage 



the First Five Lactations 





3.75—3.85 



4.281 





3.85—3.95 



4.346 





3.95—4.05 



4.411 





4.05—4.15 



4.476 





4.15—4.25 



4.541 





4.25—4.35 



4.605 





4.35—4.45 



4.670 





4.45—4.55 



4.735 





4.55—4.65 . 

 4.65—4.75 



4.800 

 4.865 



4. DO— 4. YD 



4.75—4.85 



4.800 



4.929 



4.85—4.95 



4.994 



4.95—5.05 



5.059 



5.05—5.15 



5.124 



5.15—5.25 



5.189 



5.25—5.35 



5.253 



5.35—5.45 



5.318 



5.45—5.55 



5.383 



5.55—5.65 



5.448 



5.65—5.75 



5.513 



5.75—5.85 



5.577 



5.85—5.95 



5.642 



5.95—6.05 



5.707 



6.05—6.15 



5.772 



6.15—6.25 



5.837 



6.25—6.35 



5.901 



6.35—6.45 



5.966 



6.45—6.55 



6.031 



6.55—6.65 



6.096 



6.65—6.75 



6.161 



6.75—6.85 



6.225 



6.85—6.95 



6.290 



6.95—7.05 



6.355 



