DIGESTION EXPERIMENTS WITH CATTLE FEEDS. 



57 



Barley screenings is the residue from barley flour, which was prepared in con- 

 siderable amounts during the war period. It contained dry matter 89.73 per cent, 

 which was composed of ash 6.30, protein 9.98, fiber 19.51, nitrogen-free extract 

 61.08, fat 3.13. 



Except for its lower fiber content, it resembled both oat feed and hay in chemical 

 composition. Its total dry matter is a little better digested than oat feed because 

 of a less complete separation of the starchy matter, and it has approximately 5 per 

 cent greater feeding value. 



(a) 



Carrots. 

 Carrots fed with Hay. 



(6) Carrots fed with Hay and Gluten Feed. 



' Not included in the average. 



The digestion work with carrots is a continuation of earlier work reported in Bulle- 

 tin 181. In the present trials, two lots of carrots were fed, averaging 88.02 per cent 

 water, with dry matter composed of ash 9.91, protein 8.92, fiber 8.33, nitrogen-free 

 extract 71.61, fat 1.23. In common with most other roots, they are relatively low 

 in protein, fiber and fat, and high in ash and nitrogen-free extract. 



The first lot (periods 4 and 5, Series XXIII) was fed with hay only; the second 

 lot (periods 9 and 11, Series XXIV) was fed with hay and gluten feed; and in both 

 cases constituted about 20 per cent of the drj^ matter of the ration. 



The digestibility of the dry matter of the carrots in the present hay-carrot ration 

 was 77 per cent as against 86 per cent in five previous trials. In both experiments 

 quite wide variations are observed for which a satisfactory explanation cannot be 

 given. It is quite possible that bacterial activity in the intestinal tract was more 

 pronounced in some cases than in others. 



When the carrots were fed in combination with hay and gluten feed, their digesti- 

 bility appeared to be slightly more — 80 per cent as against 77 per cent when fed 

 with hay only. 



The fiber in carrots as well as in most roots appears to be quite completely di- 

 gested, former experiments with mangels and turnips showing a dry matter digesti- 

 bility of 87 to 89 per cent. The carrots seem to fall slightly below these figures. 



