População Protozoários Ciliados e Degradabilidade Ruminal em Búfalos e Bovinos Zebuínos sob Dieta à Base de Cana-de-Açúcar

Abstract

Three rumen cannulated buffaloes (Bubalus bubalis) and three zebu cattle (Bos indicus) were fed chopped sugar cane ad libitum and 3 kg of concentrate/animal/day during 13 weeks. After two weeks of adaptation, samples of rumen contents were weekly collected at two times: just before feeding and 40 minutes after feeding to measure the concentration and composition of ruminal fauna. Ruminal contents were mixed and re inoculated among animals from the same species after five weeks of trial starting. During the last week, degradability of DM, CP, and NDF of sugar cane and DM and CP of the concentrate were determined by in situ technique. The average concentration of total protozoa was higher in cattle (4.85 × 10 5/mL) than in buffaloes (3.82 × 10 5/mL). Percent generic composition for Entodinium and subfamily Diplodiniinae was 79.2 and 6.2% in cattle and 32.0 and 54.9% in buffaloes, respectively. There was no interaction between animal species and sampling time. Holotrich concentration increased after 40 minutes of feeding. No difference was observed between buffaloes and cattle in effective degradability of the studied nutrients with differences being observed in degradation kinetic. The buffaloes had lower concentration of rumen protozoa, higher composition of Diplodiniinae and lower Entodinium than cattle. The Holotrich species exhibited capacity of migration and sequestration within the rumen of both species; and differences in ruminal fauna did not show influence on effective degradability of sugar cane and concentrate nutrients.