Effect of harvest dates on β-carotene content and foragequality of rye (Secale cereale L.) silage andhay

摘要

Limited data about the effects of various factors on forage quality andβ-carotene content of rye produced in Korea are available, so this studyinvestigated the effects of two preservation methods. Samples were collectedfrom rye harvested every 5 days between April 25 and May 31, and comparisonswere done among rye silage wilted for different periods of time and hay of threegrowth stages of rye. For the silage, dry matter (DM), acid detergent fiber(ADF), and neutral detergent fiber (NDF) contents increased with advancedmaturity of rye, whereas crude protein, in vitro dry matterdigestibility (IVDMD), total digestible nutrients (TDN), relative feed value(RFV), and DM loss decreased (p < 0.0001). Wiltingincreased the DM content and pH value significantly (p <0.0001). Silage harvested at the heading stage had the lowest pH value (4.45),propionic acid (0.83 g/kg DM), butyric acid (0 g/kg DM), and fungi and yeastpopulations (3.70 Log CFU/g of fresh matter [FM]); conversely, it had thehighest lactic acid (9.7 g/kg DM), lactic acid bacteria (LAB) (6.87 Log CFU/g ofFM), total microorganisms (TM) (7.33 Log CFU/g of FM), and Flieg’s score(70) (p < 0.0001). Wilting elevated LAB and TMpopulations, but it had no consistent effect on other fermentation products.Both delayed harvest and prolonged wilting decreased β-carotene content.Rye silage harvested around May 9 (heading stage) with 24 h of wilting waspreferred for highland, Pyeongchang. For rye hay, advanced maturity decreased DMloss, IVDMD, TDN, and RFV, but it increased DM, ADF, and NDF significantly(p < 0.05). β-carotene was decreased by delayof hay-making. Consequently, to attain lower DM loss and higher hay quality, theharvest date of May 9 (heading stage) is recommended.