ANIMAL l>KODUCTIO]Sr. 897 



Tlie ai)i)L'n(lix iiu-liKk's tuhlcs showing the inetabohzal)le energy of coarse fodders 

 and other feeds, and the ener>;y expended by a liorse in locomotion and drawing a 

 load under different conditions. A detailed index adds to the value of the volume, 

 which summarizes in a form very useful for advanced students the experiments and 

 conclusions of the leading modern investigators, and the theories and the deductions 

 which may Ik- drawn from the large amount of valuable experimental evidence. 



The exact calculation of balanced rations, J. T. Willard {Kansas Sta. Bui. 

 II.'), pp. 97-140)- — According to the autlior, "tiie bulletin maintains, and the method 

 of calculation is based upon the fact, that, reduced to a final analysis, the balancing 

 of a ration consists in balancing the feeds used in it two by two. In this pairing, 

 any one of the feeds may be used more than once, and tlie several quantities of a 

 feed so used are finally added together to obtain the total sum. Recognition of the 

 compound nature of this sum is essential to an understanding of the theory of the 

 balancing of rations. ' ' 



The method of calculating l)alanccd rations, on the 1)asis of the protein, fat, and 

 carbohydrate content; is described and a method suggested, regarded as ample ff)r 

 practical requirements, which takes into account only j^rotein and nonnitrogenous 

 constituents. In addition a table is given which shows the relative amounts of a 

 numl)er of feeds, arranged in pairs, which must be used to ajiproximate the nutritive 

 ratios called for ])y the commonly accejited feeding standards. Figures are given for 

 14 different ratios. In the author's opinion "the mixtures given may in many 

 cases constitute a ration; in others, a ration may be compounded by using, in any 

 proportion desired, any of the various mixtures having the same nutritive ratio." 



Stock raising {Bid. Maine Dept. Ayr., 1 {1902), No. 3, pp. 83-118).— iV number of 

 articles l)y different authors on problems connected with stock feeding are int-luded, 

 as well as data recortling local crop conditions, based on statements received from a 

 nmnl)er of correspondents in different 2)arts of the State. 



Concerning the estimation of starch and the digestibility of carbohydrates, 

 S. Weiser and A. Zaitschek {Arch. Physiol. [Pfluyer], 93 {1902), No. 3-4, pp. 

 98-127). — The authors studied the estimation of starch in the presence of pentosan, 

 the estimation of carbohydrates in feces, and the digestibility of the different con- 

 stituents of the carbohydrate group with different farm animals. Starch in feeding 

 stuffs was estimated by heating the material in autoclaves for 4 hours, inverting with 

 hydrochloric acid, neutralizing and determining the amount of reducing sugars 

 with Fchling's solution. A correction was introduced for the pentosan which was 

 also converted into reducing substances, the amount being learned by determining 

 the amount of furfurol-yielding material in a suitable sample after heating in the 

 autoclave and assuming that it had a reducing value equal to that of dextrin. The 

 reducing body the authors consider to be a mixture of arabinose and xylose, and the 

 reducing value was assumed to be the same as that of dextrose, since experiments, 

 reported in detail, show that arabinose had somewhat less and xylose somewhat 

 more reducing power than dextrose, and that these values were not changed by the 

 proportions in which the materials were present. 



The auth'jrs' experiments led to the conclusion that starch in the feces of mam- 

 malia and birils can be estimated by the same methods as are used in the case of 

 feeding stuffs, that is, without the addition of phosphotungstic acid or other precipi- 

 tant. Using the methods described, analyses are rej^orted of the feeding stuffs used 

 in their experiments with different animals (meadow hay, broom corn seed, oats, 

 maize, and fodder beets) , as well as determinations of the carbohydrates in the feces 

 of the animals. 



The experiments reported were made with a horse, a duck, and steers, pigs, sheep, 

 and geese. The rations consisted of different mixtures of the feeding stuffs enumer- 

 ated and the results showed tlie digestibility of the different members of the carbo- 



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