588 EXPERIMENT STATION RECORD. 



able cellulose, starch, glucose, sugar, peptic acid, total, albuminoid and amid 

 nitrogen, and undetermined material. 



As regards the effect of sugar on the digestibility of carbohydrates the authors 

 point out that in the ration of hay without sugar the coefficients of digestibility 

 were for total crude fiber 35.24, saccharifiable cellulose 43.81, undetermined material 

 38.51, and organic material not including sugar 44.11 per cent. In the case of a 

 ration with sugar the coefficients were for total crude fiber 38.95, saccharifiable cel- 

 lulose 49.79, undetermined material 52.45, and organic material not including sugar 

 47.18 per cent. Similar values are given for the other rations with and without sugar. 



The effect of sugar on the digestibility of nitrogenous constituents and fat is also 

 spoken of, the general conclusion being drawn that sugar did not materially affect 

 the digestibility of the other constituents of a ration. The authors note that in 

 general the amid nitrogen was less completely digested than proteid nitrogen. The 

 results obtained with ether extract, as is generally the case, were not altogether 

 satisfactory. In the experiments with hay and maltine, peptic acid was quite 

 thoroughly digested. 



Poultry rearing 1 and fattening in Ireland, H. de Courcy {Jour. Bd. Agr. 

 [London'], 11 (1904), No. 5, pp. 257-268, figs. 3). — Poultry raising in Ireland is spoken, 

 of, particularly the work of the Irish Poultry Society, and brief statements made 

 regarding a feeding experiment in which 4 lots of 6 cockerels each were fed with a 

 cramming machine for 21 days. 



On a ration of equal parts of barley meal, ground oats, and fine sharps wet with 

 skim milk, a little fat being added during the last 7 days, the total gain was 8 lbs. 10 

 oz. On ground oats and corn meal 1:1 with skim milk and fat as above the total gain 

 was 7 lbs. When the grain fed was ground oats, corn meal, and barley 1:1:2 the gain 

 was 9 lbs. 14 oz., and on a ration of equal parts of ground oats and corn meal wet with 

 water, fat being added as before during the last week, the gain was 6 lbs. 2 oz. The 

 methods of dressing and marketing poultry are also spoken of. 



The amount of air space required in poultry houses, K. J. J. Mackenzie 

 and E. J. Russell (Jour. Southeast. Agr. Col, Wye, 1904, No. 13, pp. 84-102, figs. 5, 

 dgm. 1). — Observations are reported on the frequency with which chickens breathe 

 and the amount of inspired and respired air, as well as determinations of the amount 

 of carbon dioxid in the respired air and in the air of poultry houses of different 

 construction. 



The authors state that the rate of breathing may be readily measured by placing 

 a ringer on the intercostal muscles under the wing and counting the respirations in 

 a given period of time, the birds being trained beforehand so that they are not dis- 

 turbed by handling. The average rate of respiration is given as 33 per minute for a 

 young bird and 27 for an older bird. The amount of air breathed in and out was 

 measured by slipping a rubber tube wide at one end over the bird's head and con- 

 necting the other end with a large flask fitted with a water gauge. As the chicken 

 breathed the fluctuations in the air pressure were read and the volume of respired 

 air calculated. 



From the average of a number of observations the authors conclude that chickens 

 breathe about a pint of air per minute, or 1.2 cu. ft. per hour. Older birds breathe 

 more air each time than younger birds, but breathe more slowly. With an insuffi- 

 cient air supply respiration, it was found, was impeded. 



The amount of carbon dioxid in the respired air was measured by means of a 

 respiration apparatus in which the chickens were kept in a sheet-iron box with a glass 

 front through which a current of air was pumped, the experimental data being very 

 briefly reported. The proportion of carbon dioxid which poultry can endure with 

 impunity was not directly determined, but the authors estimate it provisionally at 

 9 volumes in 10,000 of air and calculate that, therefore, each bird requires at least 



