Leucaena leucocephala as a protein supplement for growing pigs.

Abstract

244 Leucaena leucocephala as a protein supplement for growing pigs G. Zakayo and G.L. Krebs Muresk Institute of Agriculture, Curtin University of Technology, Northam WA 6401 Many developing countries in the tropics are faced with the problem of inadequate food production, often due to competition of human and livestock for scarce conventional feedstuffs. A solution to this problem is the utilisation of alternative feedstuffs, which are noncompetitive with the needs for human nutrition. Such feedstuffs include the foliage Corn some food crops (e.g. cassava) and from leguminous trees (Leucaena and Gliricidia spp) (Preston, 1987). The objective of this study was to evaluate treated and untreated leucaena (L. Zeucocephala) leaf meal as a protein supplement for growing pigs. Sixteen Landrace/Large White cross pigs (8 entire males and 8 gilts) were randomly allocated to four dietary treatments in a complete randomised design. The dietary treatments were; (1) standard commercial pig growers ration (control); and grain based rations containing (2) 20% sun-dried leucaena; (3) 20% water-soaked leucaena; and (4) 20% ferrous sulphate treated leucaena. All pigs were individually penned, with feed and water provided ad-libitum. Daily feed intake was recorded and liveweights measured fortnightly. After 32 days of feeding, one pig on 20% sundried leucaena, started showing clinical signs which were assumed to be due to mimosine toxicity. The pig started going off its feed, its hind legs became weak, it had uncoordinated gait and could not stand and eat fiom the trough, instead it fed f?om a dog sitting position. After 38 days of feeding, all the pigs on sundried leucaena, showed these signs of toxicity. None of the typical clinical signs associated with mimosine toxicity (hair loss, salivation) were observed and no toxicological signs were observed Corn post mortem examination. For the whole growing period (42 days), pigs fed the watersoaked and ferrous sulphate-treated leucaena leaf meal did not show any signs of toxicity. The liveweight gains of the pigs on 20% sun-dried leucaena leaf meal were significantly lower (P < 0.05) than for the other three treatments. Feed intake and feed conversion ratio followed a similar pattern, with pigs on sun-dried leucaena, showing a significant decrease in feed intake and feeding efficiency. The results fi=om this study support the suggestion of D'Mello and Thomas (1978) that leucaena leaf meal has anti-nutritional factors, which depress feed intake, growth and efficiency of feed utilisation in pigs. However, when the leucaena is either soaked in water or treated with ferrous sulphate, it can be successfully incorporated into the ration of growing pigs at a level of 20% (of the total diet). References D'Mello, J.P.F. and Thomas, D. (1978). The nutritive value of dried leucaena leafmeal fkom Malawi: Studies with young chicks. Tropical Agriculture Trinidad 55, 45-50. Preston, T.R (1987). Pigs and Poultry in the Tropics. Technical Centre for Agricultural and Rural Cooperation: Netherlands. Table 1 Average feed intake, Iiveweight gain and feed conversion ratio of growing pigs fed untreated and treated leucaena leaf meal. Recent Advances in Animal Nutrition in Australia 1997 University of New England, Armidale NSW 2351, Australia