294 STATE BOARD OF AGRICULTURE. 



complish the desired end but which still further decreased the production of 

 the animals so treated. The matter is mentioned here because contagious 

 abortion is today far too prevalent in our dairy herds, and despite many 

 advertised and published statements to the contrary, veterinary practice is 

 none too successful in its eradication or control. 



It was the original plan to so handle the herd that each animal would freshen 

 once each year. But since this could not always be brought about within 

 exact dates the year was taken as the unit of time instead of the period of 

 lactation. In ascertaining the product of each cow the following plan is 

 used: 



The milk from each cow is weighed, recorded, and sampled, at each milk- 

 ing. The composite samples are tested for butter fat at the close of each 

 week. The pounds of milk produced by a cow in a week multiplied by the 

 per cent of fat gives the pounds of butter fat for the week. The pounds of 

 butter fat increased by one-sixth of itself gives the pounds of butter. The 

 skim-milk is estimated at 80 per cent of the whole milk. This estimate for 

 skim-milk is rather low, it being customary at creameries to allow 85 per 

 cent of whole milk for skim-milk. 



At the close of the first year the records for twenty animals were reported. 

 Before the close of the second year the herd was reduced to sixteen head. 

 No. 28 having died of pericarditis, and No. 30 being afflicted with an abscess 

 that necessitated her removal from the milking herd. No. 32 failed to 

 breed and was sold for beef, while No. 31 afflicted from the outset with a 

 peculiar milking difficulty which gradually grew worse was removed from 

 the herd. Five other cows were added to the 'herd, as follows: No. 33, 

 34, 35, 36, 37. During the next two years from one cause or another the 

 herd was gradually reduced, the chief reason being the increasing number 

 of cattle at the college and our inabihty to provide adequate accommoda- 

 tions for so many. In 1909 the last animals of the original herd were sold. 

 Meanwhile 36 yearly records had accumulated, some of the cows having 

 one record, some two and some three. 



^ In Table 1 which follows the yearly lyields for each cow are shown In 

 column one the number of the cow is 'given, the cows being numbered m- 

 stead of named. The second column gives the total days of lactation, out 

 of a possible 365, for the several lactation periods. In column three the 

 total pounds of whole milk are given. Column four shows the average per 

 cent of butter fat; column five the total pounds of butter fat; column six the 

 pounds of butter; and column seven the pounds of skim milk. 



