Ž . Small Ruminant Research 29 1998 289–293 ž Utilization of concentrate diets containing acorns Quercus / aegilops and Quercus coccifera and urea by growing Awassi lambs R.A.M. Al Jassim ) , K.I. Ereifej, R.A. Shibli, A. Abudabos Faculty of Agriculture, Jordan UniÕersity of Science and Technology, P.O. Box 3030, Irbid 22110, Jordan Accepted 13 October 1997 Abstract Ž . Thirty individually penned Awassi lambs mean BW 25.3 "0.45 kg and 4–5 months of age were used in a growth Ž experiment. This was followed by a digestion and nitrogen balance experiment using 12 lambs mean BW 35.5 "0.43 kg . and 6 months of age . Lambs in both experiments were divided into three equal groups and fed one of the three concentrate Ž . Ž mixes, two of which contained ground acorns Quercus aegilops and Quercus coccifera at 25% and 50% levels of DM % . dry weight . The aim of the work was to evaluate the usefulness of acorns as an alternative energy source for growing lambs. Ž . Ž . Concentrates were given according to BW restricted to 3.5% of BW . Daily weight gain DWG of lambs fed the control Ž . Ž . Ž . diet or 25% acorn diet was similar 186 and 189 g but higher P -0.01 than lambs on the 50% acorn diet 142 g . Feed Ž . Ž . conversion ratio kg DMrkg LW gain was lower P -0.01 for the 50% acorn diet. Digestibility coefficients of dietary Ž . Ž . constituents DM, OM, ash, NDF, ADF, and N were reduced P -0.001 and P -0.01 as a result of acorn substitution for Ž . Ž . Ž . barley. Nitrogen retention grday was also lower P -0.05 for acorn diets, but similar P )0.05 across treatments when Ž . expressed as percentage % of apparently digested N. The low cost of acorns compared with barley suggest that substitution of acorns for barley at a maximum level of 25% would be economically advantageous. q 1998 Elsevier Science B.V. All rights reserved. Keywords: Quercus aegilops; Quercus coccifera; Growth rate; Digestibility; Awassi lambs 1. Introduction The cost of sheep feeding in Jordan can account for more than 85% of the total cost of production. Barley and wheat bran are the major components of the concentrate diet locally used. Local production of ) Corresponding author. Department of Animal Science, University of New England, Armidale NSW 2351, Australia. Tel.: q61-2-6773-5124; fax: q61-2-6773-3275; e-mail: raljassi@metz.une.edu.au grains is less than the national requirement and it fluctuates from year to year depending on rainfall and market. Until recently, the government in Jordan provided a subsidy for these concentrates but only when given to breeding ewes. Now, sheep holders are forced to search for alternative feed sources. For this reason and because of the high cost of locally available animal feed, lambs are sold for slaughter as Ž . rapidly as possible. A recent report from FAO 1994 showed that lambs are often slaughtered at a greatly reduced live weight ranging between 18–22 kg in 00921-4488r98r$19.00 q 1998 Elsevier Science B.V. All rights reserved. Ž . PII S0921-4488 97 00124-7