Effect of Dried Apple Pomace (DAP) as a Feed Additive on Antioxidant System in the Rumen Fluid

Abstract

The study aimed to evaluate the effect of dried apple pomace (DAP) as a feed additive on the enzymatic activity and non-enzymatic compounds belonging to the antioxidant system in cattle rumen fluid. The experiment included 4 Polish Holstein–Friesian cannulated dairy cows and lasted 52 days. The control group was fed with the standard diet, while in the experimental group, 6% of the feedstuff was replaced by dried apple pomace. After the feeding period, ruminal fluid was collected. The spectrophotometric technique for the activity of lysosomal enzymes, the content of vitamin C, polyphenols, and the potential to scavenge the free DPPH radical was used. The enzyme immunoassay tests (ELISA) were used to establish the activity of antioxidants enzymes and MDA. Among the rumen aminopeptidases, a significant reduction (p < 0.01) from 164.00 to 142.00 was observed for leucyl-aminopeptidase. The activity of glycosidases was decreased for HEX (from 231.00 to 194.00) and β-Glu (from 1294.00 to 1136.00), while a significant statistically increase was noticed for BGRD (from 31.10 to 42.40), α-Glu (from 245.00 to 327.00), and MAN (from 29.70 to 36.70). Furthermore, the activity of catalase and GSH (p < 0.01) was inhibited. In turn, the level of vitamin C (from 22.90 to 24.10) and MDA (from 0.36 to 0.45) was statistically higher (p < 0.01). The most positive correlations were observed between AlaAP and LeuAP (r = 0.897) in the aminopeptidases group and between β-Gal and MAN (r = 0.880) in the glycosidases group. Furthermore, one of the most significant correlations were perceived between SOD and AlaAP (r = 0.505) and AcP (r = 0.450). The most negative correlation was noticed between α-Gal and DPPH (r = −0.533) based on these observations. Apple pomace as a feed additive has an influence on lysosomal degradation processes and modifies oxidation–reduction potential in the rumen fluid. Polyphenols and other low-weight antioxidant compounds are sufficient to maintain redox balance in the rumen.

The Effect of Grape Seed Cake as a Dietary Supplement Rich in Polyphenols on the Quantity and Quality of Milk, Metabolic Profile of Blood, and Antioxidative Status of Lactating Dairy Goats

“…A significantly greater GR activity in the milk of goats fed with 10% GSC in food indicates the stimulation of oxidation-reduction potential. Similar results were found in the research with dried apple pomace by Bartel et al [57]. GR is the primary enzyme involved in the metabolism of glutathione and plays a crucial role in the glutathione redox cycle, which sustains appropriate amounts of reduced cellular GSH [58].…”

Effect of Feeding Dried Apple Pomace on Ruminal Fermentation, Methane Emission, and Biohydrogenation of Unsaturated Fatty Acids in Dairy Cows

“…4 DM: dry matter; OM: organic matter; aNDF: neutral detergent fiber analyzed with α-amylase; CP: crude protein; EE: ether extract. 5 The content of phenolic acids (GEA-gallic acid equivalent) has been calculated based on a previous study [8]. 6 VEM = feed unit net energy lactation; calculated using the FeedExpert software (1.2.9, Smart Feed Ltd., Pilawy, Poland).…”

“…One possible byproduct that can be used as a feed component is dried apple pomace (DAP). The research on apple pomace has already been conducted due to its nutritional value and the abundance of apples in Europe especially in Poland, the world's second-largest apple producer [7,8]. Apple pomace consists of flesh and peels (95%), seeds (3%), and stems.…”