Relation between diet and protozoal population in the rumen

Abstract

I . Four feeding trials were made to investigate relations between diet and protozoal population in the rumen.2. When a ration containing no concentrate was used, the number of entodiniomorphs decreased rapidly. The number of entodinioniorphs increased with the amount of concentrate.Rice straw, which was used as a sole source of roughage, was not always necessary for protozoa to survive in the rumen.3. The type of diet affected the holotrich population to a much smaller extent than the entodiniomorph population.During the past two decades there has been a gradual accumulation of information about the factors that influence the number of protozoa in the rumen (Warner, 196;; Hungatc, 1966;Eadie & Mann, 1970). For example, the physical form of ration and the frequency of feeding have generally been accepted to influence protozoal concentrations in the rumen. However, much more detailed work will be needed.The present work describes four experiments designed to investigate the influence of the type and amount of diet on protozoal concentrations in the rumen. E X P ER I IVI ENT A L Feeding trialsThree Holstein cows with permanent rumen fistulas, and weighing approximately 500 kg each, were used in four experiments. Before each experiment, they were given a basal ration (B) and then other rations (1-6) as shown in Table I . They were fed twice daily at 08.00 and 16.00 hours and allowed free access to water.Expt I. Effects of three rations on protozoal population in the rumen were examined. Three cows were used in a 3 x 3 Latin square design as shown in Table I. The three treatment periods were 5 d each. As ration z contained no roughage and was generally poor, each treatment period was followed by 10 d intervals on ration B to restore the condition and appetite of the animals. On the last days of three treatment periods, samples of rumen fluid were collected at 15.30 hours through the fistula by the use of a vacuum pump and a rubber tube.

Effect of feeding regime on the metabolism of ochratoxin a during thein vitroincubation in buffered rumen fluid from cows

“…This is consistent with results of a preceding study obtained with rumen fluid from cows fed grass or hay as basic components and increasing amounts of concentrate (Müller et al, 1998). It is well known that the total number of protozoa increases when the level of concentrate in the total diet is increased up to a threshold level of about 60% (related to DM), this level being accompanied by less than 10% of structural fibre Abe et al, 1973;Lyle et al, 1981;Jouany, 1988). According to Dehority and Orpin (1988), diets containing 40 to 50% roughage will support maximum protozoal numbers with a diverse fauna.…”

Macroecology of the host determines microecology of endobionts: protozoal faunas vary with wild ruminant feeding type and body mass

“…In addition, %grass did not influence Isotrichidae. Isotrichidae may be less affected by changes in the diet than other protozoa groups (Abe et al , 1973). Notably, Isotrichidae were observed in relevant proportions not only in large grazing ruminants but also in the largest browsing ruminant, the giraffe Giraffa camelopardalis (Table 2).…”

The effect of acid drinking water on rumen protozoa in the blesbok (Damaliscus dorcas phillipsi)

“…A number of studies have shown that lowering of rumen pH by feeding high concentrate diets markedly lowers protozoa concentrations (Latham et al,1971;Abe et al, 1973;Mackie et al,1978;Towne et al, 1988;Franzolin and Dehority, 1996). Dehority (2005), working in vitro with monocultures of Entodinium caudatum, Entodinium exiguum, Epidinium caudatum and Ophryoscolex purkynjei, observed that numbers of all four species decreased markedly below pH 5.8 and the protozoa were no longer viable at a pH of 5.3.…”