Investigating chemical composition and effect of different dietary levels of whole cucumber plant on rumen fermentation kinetics and nutrients digestibility in vitro

This study was conducted to evaluate nutritive value of whole cucumber plant (WCP) and then, assessing its different dietary levels effects on in vitro gas production and rumen fermentation parameters using cow rumen liqour. For this purpose, firstly chemical composition and rumen fermentation kinetics of WCP were compared with wheat straw (WS) and alfalfa hay. After that, the effects of substituting levels of 0, 5, 10, 15 and 20% WCP for forage part of the diet were investigated on in vitro digestion and fermentation parameters. Results indicated that WCP had lower dry matter (DM), organic matter (OM) and lignin contents than alfalfa and WS (P<0.05). However, its crude protein (CP) was considerably higher than WS and also was comparable with alflalfa CP content. Neutral detergent fibre and acid detergent fibre contents of WCP were lower than WS (P<0.05), but they were similar to alfalfa. Incubation of WCP showed higher total gas production (GP), potential of GP (b), DM and OM digestibility and microbial mass production than WS, while they were lower than alfalfa (P<0.05). In conclusion, results of present study showed that WCP has favourable chemical composition and nutritive value compared to WS, and its CP content also is comparable with alfalfa. Moreover, its incorporation in ruminant nutrition up to 20% of diet is recommended.