AtflMAL PKODUCTION. 



1107 



after the ninth or tenth week will seldom leave any margin of profit, after deducting 

 the cost of feed." 



As regards breeds, the Peking and Indian Runner Pekins matured the fastest. 

 "They were ready to kill fully one week in advance of the Eouens." 



Digestion experiments with poultry, E. W. Brown {V. S. Dept. Agr., Bureau 

 of Animal Indut^try Bid. 56, 2>P- 112, ph. 4, charts ^). — The digestibility of corn, oats, 

 wheat, and meat was studied with hens, the feces being collected with the aid of a 

 specially constructed aluminium pan attached to the birds by straps. The feces were 

 preserved for analysis by covering them with 95 per cent alcohol slightly acidulated 

 with acetic acid to prevent the loss of ammonia. Full analyses of the feed and feces 

 were made. 



In addition to the usual determinations the ammonia, metabolic products, uric 

 acid, pentosans, soluble ash, and silica in the feces were determined. The estima- 

 tion of the uric acid is of special importance in experiments with poultry, as this 

 represents the bulk of the urine nitrogen. It was determined l)y a modification of 

 Kionka's method « by titration with piperidine, using phenolphthalein as an indi- 

 cator. Sixteen experiments of from 6 to 13 days' duration are reported, in each of 

 which the feeding stuffs selected were fed alone during the experimental period and 

 during a preliminary period of 5 to 8 days. The following table summarizes the 

 coefficients of digestibility obtained: 



Coefficients of digestibility of a number of feeding stuffs — Experiments xvlth hens. 



Corn, average of 5 tests 

 Oats, average of 8 tests 



Wheat, 1 test 



Beef, average of 2 tests 



Organic 

 matter. 



86 64 

 64.77 

 83.94 

 87.05 



Protein. 



S3 95 

 73.38 

 77.40 

 90. 20 



Ether 

 extract. 



85. 32 

 81.48 

 58. 83 

 86.30 



Crude 

 liber. 



''14.53 



('8.15 



Nitrogen- 

 free 

 extract. 



89. 25 

 70.77 

 86. 02 



Pento- 

 sans. 



C30.05 

 dl0.80 



bNot regarded by author as reliable, 

 c Average of 3 tests. 

 d Average of 7 tests. 



On the basis of the amounts of food consumed and digested the following feeding 

 standards were calculated, which the author regards as provisional: 



Feeding standards for liens. 

 [Amounts per day per 100 lbs. live weight.] 



AMOUNTS CONSUMED. 



Hens (3 to 4 pounds), corn 



Hens (3 to 4 pounds), oats 



Hens (3 to 4 pounds), wheat... 



AMOUNTS ASSIMILATED 



Hens (3 to 4 pounds), corn 



Hens (3 to 4 pounds), oats 



Hens (3 to 4 pounds), wheat... 



Organic 

 matter. 



Pounds. 

 4.83 

 2.84 

 3.27 



4.19 

 1.83 

 2.70 



Protein. 



Pounds. 



0.53 



.37 



.42 



Ether 

 extract. 



Pounds. 



0.28 



.15 



.07 



.24 

 .12 

 .04 



Nitrogen- 



tree 

 extract. 



Pounds. 

 3.89 

 1.97 

 2.72 



3.46 

 1.39 

 2.42 



Fuel 

 value. 



Calories. 

 100, 732 

 54,065 

 66,259 



88, 623 

 39,438 

 56, 681 



Nutritive 

 ratio. 



1 : 8. 6 

 1:6.3 

 1:6.9 



1: 9.0 

 1 : 6. 

 1:7.8 



«Arch. Internat. Pharmacodynamie, 7 (1900), p. 55. 



