Influence of the presence of protozoa on the rumen microbial population of cattle.

Abstract

Three unfaunated cattle, fitted with a rumen fistula at the age of 9 months, were fed with hay wafer and pelleted concentrate. After two unfaunated cows were inoculated with a mixed population of protozoal species, changes of the bacterial populations as well as volatile fatty acids (VFA) and NH3 production in the rumen were followed for one month. The protozoa! inoculum was prepared by using the rumen fluid obtained from a fistulated cattle given hay and concentrate ration. The third cow was kept protozoa-free as a control animal. A mixed population of protozoa established in the rumen of two cows within one month after inoculation. The number of total culturable anaerobic bacteria, amylolytic bacteria and cellulolytic bacteria decreased after the inoculation of protozoa. In contrast, the numbers of methanogenic bacteria, sulfate-reducing bacteria and anaerobic fungi increased after the inoculation of protozoa. The number of lactate utilizers decreased within 9 days after the inoculation of protozoa, and thereafter increased to the original level. Neither the number of xylanolytic bacteria nor pectinolytic bacteria changed after the inoculation of protozoa. The proportion of Ruminobacter amylophilus of total culturable bacterial population was reduced most significantly by the presence of protozoa, while that of Butyrivibrio spp., Selenomonas spp. and Clostridium spp. was increased. The NH3 and VFA production increased along with the proportion of butyrate after the inoculation of protozoa. The presence of protozoa affected markedly not only the number and constitution of bacterial populations, but also the NH3 and VFA production in the rumen.

The effects of high dose of two manganese supplements (organic and inorganic) on the rumen microbial ecosystem

“…In our study, we observed a decrease the amylolytic specific catalytic activity only in the group with inorganic Mn in comparison to the control group. The results are consistent with other studies in which a negative impact of ciliates on rumen amylolytic bacteria was found [ 44 , 45 ]. CMC-ase specific activity was increased by both Mn supplements in comparison to control group.…”

The role of anaerobic gut fungi in ruminants

“…This relationship has been confirmed in several studies (Romulo et al 1986(Romulo et al , 1989Hsu et al 1991). Defamation has also been accomplished by other than chemical methods and the same general inverse relationship between anaerobic fungi and ciliates was frequently observed (Newbold & Hillman, 1990;Ushida et al 1990;Mathieu et al 1996), although not under all dietary conditions (Ushida et al 1990;Arakaki et al 1994). The underlying mechanism by which defamation increases the fungal population is possibly a reduction in the turnover of fungal protein in the rumen (Newbold & Hillman, 1990) and in the absence of predation on fungal zoospores by ciliate protozoa, a process which has been observed in vitro and postulated to occur in the normally faunated rumen (Orpin 1975;Joblin, 1990;Morgavi et al 1994b).…”

Stimulation of butyrate production through the metabolic interaction among lactic acid bacteria, Lactobacillus acidophilus, and lactic acid‐utilizing bacteria, Megasphaera elsdenii, in porcine cecal digesta

“…A commercial strain of Lactobacillus acidophilus (La) was also used in this study. A portion (0.2 g) of a commercial granule of L. acidophilus (Antibiophilus Granules, Meiji Seika Kaisha, Tokyo, Japan) was added to an anaerobic dilution solution (Arakaki et al . 1994).…”