The Effect of Dried Grape Pomace Feeding on Nutrients Digestibility and Serum Biochemical Profile of Wethers

The aim of this study was to find the effect of dried grape pomace (GP) feeding on the nutrients digestibility coefficients and biochemical parameters of sheep blood serum. The experiment was divided into three feeding periods-C (control), GP1 (1% grape pomace concentration), and GP2 (2% grape pomace concentration). Wethers in three groups in balance cages were housed for right feces collection. The C feed diet consisted of hay, ground wheat, soybean meal, mineral and vitamin lick. An experimental diet with 1% and 2% addition of GP from the daily dry matter intake was fed. After that, digestibility coefficients (in %) were calculated by the difference between nutrient intake and excretion. Furthermore, in the wethers' blood, biochemical parameters (mineral, energetic, nitrogen, and enzymatic profile) were analyzed. After the GP2 feeding, statistically significant higher digestibility of CP (crude protein), NFC (nonfiber carbohydrates), NDF (neutral detergent fiber), and OM (organic matter) was found. However, the addition of dried GP increased significantly the content of Cl- and decreased the value of glucose, nevertheless, their concentrations were within the reference interval. Parameters of the wethers' blood serum nitrogen and enzymatic profile were not affected by GP feeding. Dried grape pomace in an amount of 2% diet dry matter can be considered a suitable source of nutrients in sheep feeding, which in addition should improve the digestibility of diet crude protein.

Automated summary

This study found that adding 2% dried grape pomace can significantly improve the digestibility of crude protein, nonfiber carbohydrates, neutral detergent fiber, and organic matter in sheep. Despite the changes in some biochemical parameters caused by the addition of dried GP, the values remained within the normal range, and the blood serum nitrogen and enzymatic profile of the wethers were not affected.