Dec. 2, 1908.] Agricultural Gazette of N.S.TP. 1015 



When silage is pressed it rc^adily yields quantities of a brownish juice of 

 very complex composition. The amount and nature of tlie nitrogen 

 •compounds in 100 c.c. of typical sample of this juice were as follows : — 



Total nitrogen ... ... 'lei 



Nitrogen as NHj .. ... •030= 18 "6 per cent, of total 



Nitrogen as amide ... ... '014= 8"7 ,, „ 



Nitrogen as amino acid ... 'OBO^SS'S ,, ,, 



Nitrogen not accounted for .. . •028 = 17*4 ,, ,, 



A list of the more important compounds present in silage appears in the 

 :accompanying paper. It comprises a number of acids containing no nitrogen, 

 -which probably have no actual feeding value ; anvmg these are formic, 

 .acetic, butyric, caproic, and hexoic acids, two hydroxyacids, lactic and malic, 

 .and also succinic acid. There are also simple nitrogenous compounds, amino 

 acids, basic diamino acids and amides, the feeding value of which is not yet 

 •settled, but is certainly less, and probably much less, than that of protein. 

 Finally there are amines which are actually injurious, though whether they 

 normally occur to a sufficient extent to do any harm may be doubted ; cases 

 have come to our notice, however, where animals have not thriven (m silage, 

 .and the trouble may very probably be ascribed to these bodies. 



It is common to speak of the large amount of ''amides" present in silage, 

 but Table 3 shows how very small the quantity really is. Amides occur to a 

 .smaller extent than ammonia, and to a still smaller extent than amino-acids. 

 They form only about 5 per cent, of the non-protein nitrogen, and in view of 

 this fact it is highly desirable that the practice of regarfling all of the non- 

 protein nitrogen compounds as amides should be discontinued. 



The losses going on during ensilage. 



On comparing the composition of silage with that of the maize from which 

 it was formed it is possible to discover what has been the loss during the 

 process. An exact quantitative comparison is rendered impossible by the 

 difficulties of sampling and of preventing loss of ammonia, but it is quite 

 clear that a considerable amount of dry matter has disappeared during the 

 process. The loss is not- uniform throughout the silo, and no two bags give 

 exactly the same results, but the average of our experiments during 1905 

 and 1906, set out in Table 4, shows its general distribution. 



It will be noticed that the fibre is practically unaltered in amount, and we 

 liave confirmed this observation by microscopically examining sections of 

 maize and of the silage afterwards produced. We found that the epidermal 

 cells had undergone no change in the silo beyond a certain amount of 

 shrinkage; even the stomata were unaltered. Similarly the vascular bundles 

 were intact. 



The nitrogen-free extract suffers most. Direct tests showed that the sugar 

 ■disappears almost entirely. The fall in the furfurol indicates a decivase in 

 the amount of cellulose, i.e., the less resistant cellulo.se, which alone falls into 

 this group ; this was confirmed by microscopic examination, which showed 

 that many of the cells of the mesophyll were completely disintegrated. 



