Mean leaf area of the canopy for light interception by forages and mean retention time of feed in the rumen for feed ingestion by ruminants as investigated using simple models

This study was conducted to take up the following two subjects. (1) relatio nships between light interception by the forage canopy and its mean leaf ar ea weighted by the light attenuation curve [MLA], and (2) relationships bet ween feed ingestion by ruminants and mean retention time of feed in the rum en weighted by the feed disappearance curve [MRT], using simple models for forages and those for ruminants. The following results were suggested: (1) when the canogy leaf area index [L] was high the small coefficient of light extinction [K-f] enabled the canopy to have large MLA which could intercep t more amount of light, whereas the saturation of light interception occurr ed in lower L when the canopy had large K-f, (2) daily feed intake [DFI] by ruminants increased with the increase in MRT-1 [=feed disappearance rate]. The present study using simple models suggested that MLA of the canopy of forages was like MRT-1 of feed in the rumen of ruminants as indices for the estimation of energy ingestion.