COMPARISON OF THE RUMEN DEGRADABILITY AND INTESTINAL DIGESTIBILITY OF DM AND CP OF DRIED DISTILLERSS BY-PRODUCTS FROM BULGARIAN DISTILLERY COMPANIES

Miroslav Simeonov, Nikolai Todorov, Stefan Ribarsky, Dimo Girginov, Krum Nedelkov

Abstract: The objective of this study was to compare the rumen degradation kinetics and intestinal digestibility of different dried distillers by-products produced in all Bulgarian ethanol factories. Three non-lactating Jersey cows with an average body weight of 436 ± 18 kg each fitted with a rumen and T-duodenal cannulas were used in the experiment. Six dried distillers by-products (three from wheat DDGSw1, DDGSw2, DDGSw3 and three from corn DDGSc1, DDGSc2 and DDGc4 - numbers indicate the individual factory) have been collected from four of the biggest ethanol plants in Bulgaria. Tested feeds were incubated in the rumen of fistulated cows for 0, 2, 4, 8, 16, 24 and 48 in 6 replications. The effective degradability of DM was higher for both wheat and corn DDGS products from numbers 1 and 2 ethanol factories than other two sources (P<0.05). The range of CP fraction a in the by-products of Bulgarian ethanol producing plants, varied from 23.85% for DDGSw2 to 12.38% for DDGc4 with significantly higher values for wheat by-products than those from corn (P<0.05).The values obtained for effective degradability of CP at different outflow rates for wheat DDGSw1 and DDGSw2 were higher than those for dried distillers by-products from corn. It was observed a high correlation between all of the color parameters (L, a and b) of the wheat DDGS by-products and their effective degradability. Further investigations are necessary in order to check the possibilities of using those easy estimated parameters for a control of the protein nutritional value of DDGS. The intestinal digestibility of rumen degradable dry matter ranged from 51.95% for DDGSw3 to 38.26% for DDGc4 and had been significantly higher for wheat dried distillers by-products compared to DDGSc1 and DDGc4. The values for intestinal digestibility of proteins in both wheat and corn DDGS not differed significantly and it was observed a higher variation among the wheat by-products samples which were estimated to be 79.65% to 93.64%. Although, variation in nutrient contents due to the influence of different technological regimes and quality of raw materials, the results for the main parameters of the nutritional value of the feeds (PDI and PBR), obtained in the present experiment can be used about formulating rations for ruminants.

Keywords: dried distillerss by-products; intestinal digestibility; protein value; rumen degradability

Date published: 2017-04-28