The Type And Number Of Ciliate Protozoa In The Rumen, Omasum And Colon Of Tanzanian Short Horn Zebu Cattle

Abstract

Mammals lack the enzymes that are capable of digesting plant fibres. Microbes (bacteria, protozoa and fungi) enable herbivores to utilize lignocellulose and non-protein nitrogen and convert these to highly valuable products (meat and milk). In Tanzania, the bulk of beef and milk is derived from the national herd of almost entirely shorthorn zebu population of approximately 13.4 million cattle. Despite the importance of Tanzania
shorthorn zebu cattle, the microbes inhabiting the rumen, omasum and colon of these animals have not been adequately studied. Thus, this study was carried out to determine the type and distribution of ciliate protozoa in the rumen, omasum and colon of 40 Tanzania shorthorn zebu cattle slaughtered at Morogoro Municipal abattoir. Immediately after slaughter, ruminal, omasal and colon content samples were collected in clean containers. Rumen liquor was obtained by squeezing the rumen contents through two layers of surgical
gauze. Each sample was diluted by mixing 1 g or 1 ml of contents with 4 ml of 10% formalin solution to fix the protozoa. This was followed by addition of two drops of iodine tincture to stain starch granules just before identification and counting of protozoa. Standard techniques were used for the identification and counting of the microbes. The main protozoa in the ruminal and omasal contents and rumen liquor were Entodinium spp (84-93%), Diplodinium spp (6-8%), Ostracodinium spp (1.0-1.5%), and Eudiplodinium spp (1-1.4%). The total protozoal counts were 1.9 x 105, 1.4 x 104, 0.03x104/g in the ruminal,
omasal and colon contents respectively and 1.3 x 105/ml in rumen liquor. Protozoal density in the rumen contents was significantly (p<0.05) higher compared to rumen liquor, omasal and colon contents. Isotricha spp were significantly higher (P<0.001) in the rumen liquor compared to the rumen contents possibly due to their preference of soluble carbohydrates richly available in the rumen liquor. It is hereby concluded that a variety of protozoa
species exist in the gastrointestinal tract of Tanzania shorthorn zebu cattle with entodiniomorphids being the most abundant compared to holotrichs. Also
care need be taken on reported protozoal counts as variation in numbers and
types occur based on the use of rumen liquor and or rumen contents

Tanzania Veterinary Journal Vol. 25 (1) 2008: pp. 13-23