140 DAIRY CATTLE AND MILK PRODUCTION 



records, is to weigh the milk and make tests for per cent fat at 

 monthly intervals. In carrying out this method, the best 

 arrangement is to weigh the milk from each individual cow 

 for three days about the middle of the month. A composite 

 or average sample of the milk is also taken during the same 

 time, which is tested for per cent of fat. The average milk 

 and fat produced for the three days is taken as the average for 

 that month. This should be carried out regularly each month 

 during the year. The total production of each cow as shown 

 by such tests is close enough to the actual for all practical pur- 

 poses. The objections to this plan are that the owner often 

 forgets to take samples when it is not done regularly. The 

 ^advantages of having daily milk records as guides for 

 feeding and for checking up milkers should be taken into 

 account. 



Fig. 33 shows a suitable form for keeping the weights for 

 the three days. The totals for the month can be kept in the 

 form illustrated in Fig. 34. 



Testing at Intervals of Three Months. Another method 

 which has less value than either of the foregoing, but is better 

 than no testing at all, is to make the weights of the milk 

 produced by each animal and a sample covering seven days' 

 time at intervals of three months, then from this week's 

 average calculate the production for three months, of which 

 this is the middle week. 



Method of Taking and Testing Samples. Where many 

 samples are to be taken, the most convenient and accurate 

 method is with a sampling tube which can be purchased from 

 a dairy supply company. In taking a sample with this 

 arrangement, the sampler, which is a brass or copper tube, 

 is lowered in the pail of milk and then closed. The milk 



