Abstract:
(1) A technique is described for the preservation and counting of ruminal
infusoria.
(2) Reactions of specific infusoria as well as total infusorial populations
to changes in the diet of stable fed sheep were investigated.
(3) Seasonal fluctuations of ruminal infusoria of sheep grazing on the veld
are described. The amount of protein available in the pasture was shown to
have a significant influence on the density of the infusorial population.
(4) Data are presented comparing the density and types of infusoria in
veld-grazing sheep and different species of antelopes in their natural state.
(5) The digestion of maize starch within an infusorium from material in vivo
is described. The brown glycogen-like granules formed within the foodsac and
plasma of the infusorium have been shown to be glycogen synthesizing bacteria
and not actual glycogen granules as hitherto accepted.
(6) The rate of digestion of starch within the rumen was shown to be the
same whether infusoria were present or not. It was therefore concluded that
infusoria do not accelerate the rate of digestion of starch and that they merely
act as hosts to starch attacking bacteria and bacterially secreted diastatic enzymes
ingested by the organism.
(7) That infusoria assist in the digestion of cellulose could not be proved.
It was concluded that the digestion of cellulose within the body of the infusorium
is primarily due to cellulose digesting bacteria ingested by the infusorium.
