4i6 



Feeding Value of Mangolds. 



[OCT.; 



time, one farmer's efforts merely sufficing to drive the birds to 

 other farms. Rookeries should not be permitted to become too 

 extensive or too strong in numbers. 



It will be remembered that the Board recently suggested the 

 desirability of keeping the number of rooks in this country 

 within limits (see Journal, May, 1906, and July, 1906). 



With reference to the question of the extent to which the 

 percentage of dry matter in mangolds and swedes is indicative 

 of the feeding value,* some experiments 

 Feeding- Value of ^^ve been carried out at the Midland Dairy 

 * Institute with Prize Winner Yellow Globe 

 and Golden Tankard mangolds. Trials had already shown that 

 the percentage of dry matter in Yellow Globes was 9"68, 

 and in Golden Tankards 13*00, and assuming that a hundred- 

 weight of dry matter in mangolds to be worth 6s. 9d., 

 Golden Tandards would be v/orth 4s. 6d. per ton more than 

 Yellow Globes. The object of the experiment was, therefore, 

 to ascertain whether mangolds containing a high percentage 

 of dry matter possess any superiority over mangolds con- 

 taining a low percentage of dry matter, and to investigate 

 the relationship existing between feeding value and dry 

 matter for milk production when both kinds were fed in 

 equal quantities. Two lots of three cows each were tested, 

 each lot being as nearly as possible identical as regards period 

 of lactation, age, number of calves and temperament, so that 

 any disturbing factors were reduced to a minimum. Further, to 

 lessen the risk of irregularities in the experiment, due to feed- 

 ing, &c., it was decided to put the lots alternately, for three 

 weeks, on each class of root. Thus, whilst Lot i received Golden 

 Tankards Lot 2 was getting Yellow Globes, and vice versa. The 

 cows were cross-bred Shorthorns. The experiment lasted from 

 February 7th to March 21st. The foods consisted of a mixture 

 based upon the ration which was fed to the herd in the ordinary 

 way, so that there was little change in the dietary when the 



* Journal^ September, 1905, p. 353 ; August, 1906, p. 282. 



