Lignin in feeds was estimated by a new method. Lignin in grass increased with age and with higher rates of N. In the second cut lignin was higher than in the first. Lignin had more effect than crude fibre and silicic acid on digestibility. Chemical and microscopic studies showed that the lower digestibility of protein if fibre content was high was not caused by lower penetration of the cell walls by digestive enzymes. True digestibility for protein hardly depended on protein and crude fibre in the feed. Perhaps higher crude fibre content may increase the number of intestinal bacteria. More of the intestinally secreted protein would then be incorporated in bacteria which would stimulate the protein secretion, and increase the amount of metabolic faecal protein. There might be a limit to the increase in metabolic faecal protein, reached in ruminants and in pigs on rations with crude fibre contents similar to those in ruminant rations.
|Qualification||Doctor of Philosophy|
|Award date||28 Jun 1946|
|Place of Publication||Groningen|
|Publication status||Published - 1946|