17 goats were assigned to three feeding groups and were used to determine ruminal pH, concentrations of SCFA and ruminal protozoal concentrations under different levels of concentrate feeding. Group 1 existed of 5 goats and was fed with hay over the whole study. 6 goats were allocated to group 2 and they were fed with 30% barley and 70% hay. Group 3 consisted of 6 goats. This group got 60% barley and 40% hay. Group 2 and group 3 passed through a feeding phase in which the concentrate level was slowly enhanced to accustom the animals for increasing concentrate level. At the beginning of the study ruminal fluid was sampled with an oro-ruminal probe. At the end of the study the ruminal fluid was taken directly out of the rumen in time of pathological examination. Ruminal pH, total SCFA concentrations, concentrations of Acetate, Propionate, Butyrate, Iso-Butyrate, Valerate and Iso-Valerate and concentrations of entodiniomorphid and holotrich protozoa were analyzed. The method of sampling the rumen fluid had a significant influence on the parameters, which were detected in this study. The pH-values showed significant differences between group 3 and group 1 (P=0.001). Between group 2 and group 3 a trend was seen (P= 0.02).
The concentrations of the protozoa were influenced by the method of rumen fluid sampling and showed diet dependent differences only at the end of the trial (P=0.002). In tendency group 1 had a lower protozoal concentration compared to group 2 (P=0.079). Between group 1 and group 3 was a significant influence of the ration measurable (P=0.001). Analyzing short chain fatty acids showed high significant influences of the way of samling ruminal fluid (P≤0.001). On the one hand feeding showed a trend by enhancing concentrations of Propionate (P=0.009) and on the other hand the composition of feeding had an significant influence of the concentration of Isobutyrate (P=0.001). It was concluded that feeding high levels of concentrate did not influence rumen metabolism and rumen protozoa concentration in an dramatic way, if animals were adapted to this feeding regime slowly.