646 



Journal of Agricultural Research voi. xiii, no. u 



Table VI. — Time required for the passage of residues through the several organs 



To have made this study more complete would have required accurate 

 measurements of the capacities of the several organs. However, the 

 dry-matter contents of the several organs are probably the most satis- 

 factory for making these studies. Some linear measurements of the 

 several organs were made, and these are presented in Table VII. 



Table VII. — Linear measurements of organs 



Steer No. 



52 



49 

 46 



45 

 44 

 53 



Caecum.o 



Meters. 



3-55 

 ■58 

 •44 

 •53 

 •65 

 •38 



a Also figured in large intestines. 



CONCLUSIONS 



(i) More than half of the comminution that takes place in average 

 rations containing coarse feeds takes place as a result of mastication. 



(2) When rations are incompletely masticated, a higher percentage of 

 the comminution takes place in the rumen and reticulum. 



(3) About the same extent of comminution takes place in the omasum 

 and abomasum. 



(4) The amount of comminution is not alone dependent on the time 

 food residues remain in the several organs, but it is also dependent on the 

 functional activity of the several organs. 



(5) Absorption takes place to the greatest extent in the intestines. 



(6) Absorption tends greatly to lessen the quantity of residues below 

 2 mm. and proportionately to increase that above 2 mm. 



(7) The comminution of silage-alone rations during the process of di- 

 gestion is over 90 per cent efficient, with 2 mm. as the dividing line. 



