Nutritive value, phenolic compounds and in vitro digestion parameters of barberry (Berberis vulgaris) harvest residues in comparison with alfalfa hay

Food- feed competition is one of the main challenges in the sustainability of livestock production systems. From this point of view, it is important to identify the nutritional value of agricultural waste as an alternative for animal feeding. The current study was carried out to evaluate nutritive value, phenolic compounds and in vitro digestion characteristics of different parts of Berberis Vulgaris plant. The experimental treatments included: 1) alfalfa hay, 2) barberry branches, 3) leaves before barberry harvesting, 4) leaves after barberry harvesting and 5) a mixture of branches and leaves (in the ratio of 60:40). The samples of barberry harvest wastages were manually prepared and sun-dried. The chemical compositions and phenolic compounds of samples were determined according to standard laboratory methods after milling samples and gas production of samples was assessed at zero, 2, 4, 8, 12, 16, 24, 48, 72 and 96 hr. The results revealed that dry matter, organic matter and ash content were similar among treatments. The highest crude protein was observed in barberry leaf; also the main tannins in barberry wastes were hydrolysable. Gas production rate (c) was the same among treatments; however, the highest gas production potential (b) was observed in leaf (P<0.05). Feed fermentation efficiency, organic matter digestibility, metabolizable energy and net lactation energy were also higher in barberry leaf than alfalfa hay (P<0.05). In conclusion, barberry harvest residues (except branches) has acceptable nutritional value and due to its large volume in South Khorasan province, the possibility of industrial scale preparation and lower cost than alfalfa, can be used as a replacement for current forage like alfalfa in ruminant nutrition.