Abstract

In Sweden it is mandatory to keep pigs at pasture between May and September in organic farming. Farmers are recommended to increase feed allowance by 15-20%. We compared two methods for accomplishing the feed energy increment, with regard to pasture intake and total consumption ability. Growing pigs at pasture were given 15% extra metabolizable energy (ME) above indoor recommendations by increasing energy concentration (Conc.) or volume (Vol.) of a standard diet. A total of 54 pigs were included divided on the two treatments and on two replicates. In total, Conc. groups increased their DM intake by 10% (pasture) and ME intake by 19% (13.7 feed and 5.7 pasture) above indoor requirements. Correspondingly, the Vol. groups increased their DM intake by 15% (7.6 feed and 7.6 pasture) and ME intake by 12% (7.6 feed and 4.2 pasture). Daily weight gain (DWG) for Conc. and Vol. treatments was 879 and 912 g (P = 0.109) and the dressing percentage was 77.8 and 75.8 (P = 0.002). Carcass traits were not significantly different. Both Conc. and Vol. pigs grazed at pasture. An increment in ME intake up to 10% can be carried out either by increasing feed volume (amount) or feed ME concentration in addition to grazing. For a further increase, feed ME concentration must be enhanced to avoid limitations in total consumption ability. (C) 2002 Elsevier Science B.V. All rights reserved

Published in

Livestock Production Science
2003, volume: 80, number: 1-2, pages: 167-174
Publisher: ELSEVIER SCIENCE BV

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