Effect of the passage through the digestive tracts of domestic ruminants on the germination of woody leguminous tree seeds in the semi-arid tropics

Abstract

The survival and germination rates of seeds of seven leguminous tree species (A. nilotica adansonii, A. raddiana, A. senegal, A. seyal, B. rufescens, F. albida and P. juliflora) were studied after their ingestion and excretion by cattle, sheep and goats.

The results show that:

- hard seeds remain intact and keep their viability after excretion by domestic ruminants, whereas seeds with permeable integuments are destroyed;

- cattle excrete a higher proportion of intact seeds than small ruminants. This difference seems mainly related to a stronger masticatory activity of sheep and goats;

- germination of hard seeds is not improved by passage through the digestive tracts of ruminants.

In conclusion, ingestion of hard seeds by domestic ruminants cannot be considered as a way of breaking dormancy, but only as a means of dispersing seeds which are intact.