Vyvoj bachorovej fermentacie teliat v obdobi mliecnej vyzivy.
1992
Bomba A. | Zitnan R.
The concentrations of total volatile fatty acids (VFA)in the rumen fluid were increasing with the age of the animals. A significant increase in the concentrations of total VFA from 70.93 to 90.71 mmol/l was observed in the age period of 5 - 7 weeks and a highly significant increase in the age period of 9-11 weeks. At the average age of seven weeks the lower boundary of the reference value range (80-120 mmol) of the total VFA concentrations in the rumen fluid as mentioned for adult animals was exceeded in the experimental calves. The molar proportion of acetate decreased from 74.04 mol %at the age of three weeks to 67.54 mol % at the age of 11 weeks, and the propionate proportion increased from 16.73 to 19.53 mol % within the same interval. These changes influenced the acetate to propionate ratio, and simultaneously the energetic efficiency of VFA production. The acetate:propionate ratio was directly, but negatively dependent on the energetic efficiency. A significant increase was observed in isobutyrate and isovalerate levels at the age of 3-5 weeks. The age period of 7-9 weeks in calves can be recommended as convenient for the gradual transition to vegetable nutrition.
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