[An oral-ruminal probe for rumen sampling in the adult sheep]

Ten adult (height: 63-85 cm) rumen-fistulated sheep were used to test the usefulness of an ororuminal probe and a suction pump for the acquisition of ruminal fluid. The use of these instruments in 50 samplings rendered 200 ml of ruminal fluid each time. The introduction of the probe took 18 +/- 6.5 s, whereby the probe was inserted to a length of 91.3 +/- 3.5 cm. The collection of 200 ml of ruminal fluid took 7.4 +/- 2.2 s. The sampling location was the ventral ruminal sack. By comparing the fluid taken by the ororuminal probe with samples taken via ruminal fistula by a tube-like probe no significant differences in regard to pH, total acidity, reduction potential, ammonia, acetate, L-lactate, sodium and chloride concentrations were found. However, significant differences between ororuminal probe samples and fistula samples were observed in regards to the concentrations of total volatile fatty acids, propionate, n-butyrate, i-butyrate, n-valeriate, i-valeriate, calcium, phosphate, magnesium and potassium. The differences were independent of the sampling order (ororuminal probe prior to fistula and vice versa). These results indicate that samples taken by the ororuminal probe do not contain sampling-dependent saliva residues. Those samples collected via fistula had consistently higher concentrations of total volatile fatty acids, propionate, n-butyrate, i-butyrate, n-valeriate, and i-valeriate, as well as higher concentrations of calcium, phosphate, magnesium and potassium than samples taken with the ororuminal probe. These results indicate that samples taken via fistula originated from more dorsal regions than the samples taken by ororuminal probe from the ventral ruminal sack. The ororuminal probe and the suction pump used proved to be useful for the collection of ruminal fluid from the ventral ruminal sack in adult sheep (height: 63-85 cm).