ANIMAL PRODUCTION. 71 



was found that groats produced from 10 to 30 cc. of bydrogen and niethiiu por 

 liour, wbicli is equivalent to from 3.5 to G.6 per cent by vobune of the total 

 carbon dioxid produced in the same time. " On an average the combustible 

 },'ases equal 5 per cent of the total CO2, and an average goat of 120 kg. produces 

 about 9 liters a day. The proportion between H and CH4 is variable : on an 

 average the CH4 forms two-thirds of the total combustible gas." 



A study of the ratio of carbon dioxid to hydrogen and niethan led to the con- 

 clusion that it is not unreasonable to assume that at least twice as much carbon 

 dioxid as combustible gas arises from fermentation in the alimentary tract. 

 " Since the combustible gas equals 5 per cent of the total CO2, it follows that 

 on an average at least 10 per cent of the total observed CO2 arises from fermen- 

 tation and not from tissue metabolism. There is little doubt that the bacterial 

 action concerned in these processes goes on anserobically. . . . 



"The mean respiratory quotient falls from 0.95 to 0.S5 (at most), a figure 

 which is not in accordance with the view that cellulose is dealt with by the 

 tissues as a carbohydrate rather than as a fatty acid arising from the carbo- 

 hydrate by bacterial action before assimilation. 



" It would seem appropriate that the respiratory activity of different animals 

 should, for comparative purposes, be expressed in terms of their * clean ' weight, 

 i. e., the total weight less the contents of the alimentary canal. A number of 

 observations have shown that the contents of the stoaiach and intestines consti- 

 tute on an average IS.S per cent of the total body weight in goats, the extreme 

 figures being 16.4 per cent and 22.7 per cent." 



Making corrections for the contents of the intestinal tract, the authors calcu- 

 late, on the basis of 27 determinations, that the average carbon dioxid produc- 

 tion of normal goats is 453 cc. or 0.S9G gm. per kilogram body weight per hour. 



Yearbook of scientific and practical animal breeding, R. Mijller {Jahrh. 

 Wiss. u Praia. TierzucM, 2 {1901), pp. LIV+30J,, pis. 5, map i).— The larger 

 part of this report is occupied with critical reviews of literature relating to the 

 anatomy, physiology, hygiene, feeding, geographical distribution, utilization, and 

 breeding of domestic animals of all kinds. The first part of the report contains 

 si)ecial articles on the origin of species in. domestic animals, the mutation 

 theory as ajiplied to animals, the development of horns, breeding of horses, 

 hybrids between goats and sheep, and the fertility of mules. In a short article 

 on the last-named subject (pp. LI-LIV), H. W. von Wahl presents evidence of 

 the existence of fertile mules on an estate in Brazil. It is stated that one mare 

 mule has borne colts both from jacks and stallions and that the offspring closely 

 resembled the mother. 



Live stock schemes, 1908 (Dcpt. Agr. and Tech. Instr. Ireland Jour., 8 

 (1907), No. 1, pp. 71-87). — Regulations for registration of stallions and other 

 matters concerned with the improvement of breeds of horses, cattle, and swine 

 arc recorded. 



The central zootechnic station at Sao Paulo, H. Raquet (Ann. Gcmbloux, 

 n (1907), No. 11, pp. 598-621, p?.s. 21).— In this article the author describes the 

 equipment of the Sao Paulo station for animal production, the work in animal 

 breeding and dairying, and related matters. 



Annual reports of the live stock associations of the Province of Ontario, 

 1906 and 1907 (Ann. Rpix. Lire Stock A-ssocs. Ontario, 1906-7. pp. i?,?).— 

 ReiMirts and jiapers presented at meetings of different provincial live stock asso- 

 ciations and similar matters are included. 



Animal husbandry in Denmark, 1906, A. Appel (Tidsslcr. Landokonom., 

 1907, No. 7. pp. .'i01-.'il7). — A general survey. 



53818— No. 1—08 6 



