Digestibility and energy content of Paulownia (Paulownia elongata S.Y.Hu) leaves

G. Ganchev1*, А. Ilchev1, А. Koleva2

1Department of Morphology, Physiology and Animal nutrition, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria 2Department of Technology of cereals, fodder, bread and confectionary products, Technological Faculty, University of Food Technology, 4000 Plovdiv, Bulgaria

(Manuscript received 5 July 2019; accepted for publication 3 September 2019)

Abstract. The aim of the study was to determine the digestibility and energy content of Paulownia elongata S.Y.Hu leaves after leaf fall. Leaves together with petioles were dried at room temperature and milled with a roughage mill before feeding to animals. A classical digestion trial was performed, with three rams weighing 55.4kg on average, by determining the chemical composition of consumed feed, feed leftovers and excreted faeces. Digestibility was evaluated as difference in the amount of ingested nutrients and nutrients excreted with faeces and it was determined to be 50.72, 52.08, 31.63, 54.09, 55.15 and 56.06% for dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), crude fibre (CF) and nitrogen-free extract (NFE). The energy value for ruminants calculated on the basis of chemical composition and established digestibility was 8.29 MJ digestible energy (DE)/kg DM, 6.55 MJ metabolizable energy (ME)/ kg DM, 0.59 feed units for milk (FUM)/kg DM and 0.52 feed units for growth (FUG)/kg DM.