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MASS. EXPERIMENT STATION BULLETIN 230 



high phosphorus content, so that in so far as ash requirements are concerned 

 it makes little difference what grain ration is fed. 



2. All dairy cows should have a dry period of two months, during which 

 time they should be liberally fed on a legume roughage, or on early cut hay 

 containing clover, or on rowen, as well as on some grain to make up for the 

 losses in mineral matter during the period of heavy milking. Good pasturage 

 will also prove very satisfactory. 



3. Growing heifers should receive special care with respect to the ash 

 content of their rations. Here again some kind of properly cured legume 

 or clover-mixed hay is the best safeguard. 



4. Put the bone meal and other mineral substances on the land, rather 

 than in the manger. Used in this way the yield and ash content of the crop 

 are likely to be increased and thus indirectly the ash requirements of human 

 beings and animals will be taken care of. 



5. Common salt is the one exception to all the above statements. Animals 

 should have free access to it at all times. 



The above recommendations are what many successful dairymen now prac- 

 tice, and are within the reach of all who wish to improve their feeding prac- 

 tices in this respect. 



NOTE: It is possible that most cows when fresli are in negative calcium 

 balance; that is, they excrete in the milk and manure more calcium than they 

 consume. This condition in all probability is more pronounced and continues 

 for a longer period in case of cows bred for heavy milk production. It has 

 been shown recently by the Wisconsin Station that direct sunlight checks this 

 tendency to a limited extent. Whether the antirachitic vitamin is of pro- 

 nounced influence in aiding calcium assimilation in case of dairy cows is still 

 an open question. 



