Leaf protein from green pulse crops and nutritive value of legume protein concentrates for poultry

Authors

• Matti Näsi Department of Animal Husbandry University of Helsinki SF-00710 Helsinki
• Tuomo Kiiskinen Department of Animal Husbandry Agricultural Research Centre SF-31600 Jokioinen

DOI: https://doi.org/10.23986/afsci.72192

Abstract

Leaf protein concentrate (LPC) samples were prepared from four pulse crops, goat’s rue, pea, field bean and Persian clover. Their proximate composition was 42.5— 53.4 % crude protein, 2.1—7.9 % ether extract and 1.0—3.0 % crude fibre. The lysine content was 4.1—4.8 g/ 16 g N, that of sulphur amino acids 2.0—2.8 g and that of threonine 4.5—4.8 g. The contents of tannins varied from 2.2 to 5.5 %. The nutritional values of the LPC samples were assesed in digestibility and balance trials with male chickens of 16—18 weeks, LPC composing 25 % of the diets. LPC from pea had the highest digestibilities of organic matter (70.3 %), crude protein (77.6 %) and carbohydrates (54.9 %), while LPC from Persian clover had the lowest (P < 0.01). The true digestibilities of crude protein for goat’s rue, pea, field bean and Persian clover were, respectively, 70.0, 82.2, 69,7 and 56.8 % (P < 0.01). The digestibilities of nutrients in the present LPC samples were rather low compared to their minimal crude fibre content. A reason for this may be the contents of tannins. The AMEN values for the LPC’s of goat’s rue, pea, field bean and Persian clover were, respectively, 10.79, 13.15, 9.80 and 9.18 (P < 0.01). The gross energy metabolization ranged from 42.6 to 57.0 %.