Recovery of pasture seed ingested by ruminants. 3. The effects of the amount of seed in the diet and of diet quality on seed recovery from sheep

Abstract

We determined how the recovery, rate of passage and viability of pasture seeds fed to sheep were affected by the quality of the associated diet and by the proportion of seeds in the diet. Penned sheep were fed basal diets of low (45%), medium (60%) and high digestibility (70%). A proportion of each diet (20%) was milled, and on 1 day half of the milled feed was replaced by a mixture of seeds of carpet grass (Axonopus afinis), Pensacola Bahia grass (Paspalum notatum), Kenya white clover (Trifolium semipilosum) cv. Safari and shrubby stylo (S. scabra) cv. Seca. Seed was fed at 3 levels; 12 000, 18 000 and 24 000 seeds of each species. Faeces were collected for 5 days after feeding the seed and germination tests carried out on seed washed out from the faeces. The proportion of seed in the diet had no effect on percentage seed recovery or on the viability of recovered seed. However, only 10% of ingested seed was recovered with the low quality diet, compared with 28% with the medium and high quality diets. Less Seca seed was still in pods with the low quality diet (6%) than with the medium and high quality diets (11%).