Rumen ciliate protozoa in cattle fed elephant-grass and two concentrate levels

Abstract

The influence of elephant grass (Pennisetum purpureum) and two levels of concentrate (20 and 40%) on rumen ciliate protozoa were evaluated in seven lactating Holstein-Zebu crossbred and rumen fistulated cows. The animals were provided with three diets: only elephant grass (D1) and forage plus 20 and 40% of concentrate, D2 and D3, respectively. Ruminal fluid samples were obtained by emptying the rumen, homogenized and kept in an equal volume of 18.5% formalin. The following ciliates were identified and quantified: Charonina, Dasytricha, Diplodinium, Diploplastron, Entodinium, Eodinium, Eremoplastron, Eudiplodinium, Isotricha, Metadinium e Polyplastron. There were no difference on the mean concentration of ciliate protozoa and for mL of ruminal content, which were 48.75 x 104 (D1), 60.54 x 104 (D2) e 54.30 x 104 (D3). The Entodinium genus predominated in the three diets, 73.5%, 76.9% and 72.2% of the total of ciliates for D1, D2, and D3, respectively. Levels of 20 and 40% of concentrated in the diet did not affect the pH and the rumen ciliate protozoa population in the rumen of cows fed elephant grass.