Variability in chemical composition of straws

Transcription

1 Variability in chemical compositi straws Antgiovanni M., Sargentini C. in Tisserand J.-L. (ed.), Alibés X. (ed.). Fourrages et sous-produits méditerranéens Zaragoza : CIHEAM Optis Méditerranéennes : Série A. Séminaires Méditerranéens; n pages Article available line / Article dispible en ligne à l adresse : To cite this article / Pour citer cet article Antgiovanni M., Sargentini C. Variability in chemical compositi straws. In : Tisserand J.-L. (ed.), Alibés X. (ed.). Fourrages et sous-produits méditerranéens. Zaragoza : CIHEAM, p (Optis Méditerranéennes : Série A. Séminaires Méditerranéens; n. 16)

2 CIHEAM - Optis Mediterraneennes Variability in chemicalcompositi straws M. ANTONGIOVANNIAND C. SARGENTINI DI cell-walls by lignin, its soluble phenolic compounds and silica. - Variabilité de la compositi des pailles. La variabilité de compositi des diflérentes pailles est csidérée. Les polyholosides cstituants des parois cellulaires st des sowces énergétiques potentielles pour les ruminants, mais leur utilisati est limitée par les effets negatifs sur la digestibilité déterminés par la lignine, ses acides phénoliques solubles et par le bioxyde de silicium. Introducti as abundant and likely in quantity in the because the need and human csumpti. almost made cell-walls.and cell-walls made highly lignified and small amounts and low digestibility. animal feed, due tive value both by means and the associati with in balanced diets. it look at the chemical compositi in optimize its use as animal feed. Compositi straws Botanical fractis The main botanical nodes, and leaves (blades and sheaths). The these species and with many such as at soil and climate cditis, etc.. Since the chemical compositi ous is the chemical compositi the as a csequence. Table 1 shows the compositi Table 1 is Table 2, it is evident that, the ences botanical ent the same as wheat 41 51%; nodes 5 almost 8%; leaves 29 than 36%. Table 1. Botanical fractis some cereal straws. % Node, % Leaf, % 58 l 35 Oat Wheat ( and Aman, n.o : 49-53

3 CIHEAM - Optis Mediterraneennes Table 2. Botanical fractis straws some varieties oat and wheat. Table 3. Chemical compositi straw botanical fractis. Oat varieties: Cabana Leanda Wheat varieties: Aquila Aval Galahad Lgbow Stets O % Node, % Leaf, % Chaff, % Wheat Cstituent Node Leaf Node Leaf N * Cellulose Ash Silica ). (lg by Aman, Cstituent Node Leaf Node Leaf N * Cell-wall Ash Silica Walli et al., Shand et al Chemical compositi Leaves and nodes in gen and ctents (see Table 3): and hemicellulose in leaves and nodes and less cellulose than in the highest silica ctent is that leaves, while the most lignified is S. Thiago and 1982). 1.- and lignin Cell-walls made types cellulose, hemicellulose and pectic ides. compents the polyglucans, and mannans. cellulose and xylan hemicellulose the compents. Few pectic compounds and few mannans also Ethanol ctain the low weight glucose, and mannil Lignin is the well-known complex substance covalently bound side chains xylans cell-walls. sents an obstacle digesti both because it is a physical and because the effect activity, due the phenolic compounds it ctains. As shown in Table 4, cell-wall ctent is about SO%, with a and a in the case wheat (65% a Canadian and 84% by The cellulose ctent is in in wheat. The hemicellulose quantitatively between and wheat, with a within wheat. Wheat lignified but, again, the is quite Simple phenolic which cstituents lignin, easily solubilized within the significantly the value The ant phenolics (FA), but compounds as shown in Table 5. The activity phenolic compounds has been (Jung and Fahey, 1983; Jung et al., 1983; et al., 1988; Jung, 1988). Lignin is not so an as it was thought.

4 CIHEAM - Optis Mediterraneennes Table 4. Cell-wall compositi straws. Table 5. Phenoli compounds ctent cereal straws. VA FA (1) (2) (2) (2) (2) (4) (7) (13) (14) (9) Oat (1) (1) (3) (3) Wheat (1) Wheat (2) Wheat (4) Wheat (5) Wheat (6) Wheat (6) Wheat (6) Wheat (6) Wheat (7) Wheat (8) Wheat (9) Wheat (10) Wheat (11) (12) (12) (1) (2) et al., 1988; (3) Walli et al., 1988; (5) Antgiovanni et al., 1983; (6) (7) Givens et al., 1989; (8) et al, 1988; (9) Adebowale et al., 1989; et al., 1989; (12) Chenost, 1989; (13) Wanapat et al. 1985; Barley: Wing (1) (1) Cilla 1170 (1) (1) Senat 3520 (1) (2) Oat: 290 Titus (1) (1) (1) Wheat: (1) (1) (2) et al., 1978; (2) Jung and Fahey, 1983; Legenda: = VA = Vanillic Acid; = FA = plant ible. the the live as a part lignified cell-walls in due soil cditis, time, climate cditis the etc.. the associated with the cell-wall cstituents (lignin, silica), thus and digest- and Aman (1984) (Table 6), 24 up 54 g/kg the data: 1978; 1989, in the same table 6; Walli et al., 1988 (44 and 36 g/kg in et al., 1988 (74 g/kg in (25

5 CIHEAM - Optis Mediterraneennes ~ ~~ Table 6. Crude protein ctent cereal straws. Sweden USA and (1) Canada (2) (1) (3) Oat Wheat ples. One the is silica, in and in the leaves Quite in this is Table 7, must be emphasized the negative effect high silica, as in with in the Jes, 1968). References (2) INRA, 1978; 8: Effect alkali. 48: gaseous am- 56 g/kg in wheat); Shand et al., 1988 (28 g/kg in wheat and 47 g/kg in oat); Adebowale et al., 1989 (48 g/kg in wheat); Chenost, 1989 (29-45 g/kg in et al., 1988 (31 g/kg in wheat); Silva et al., 1989 (31-37 g/kg in AMAN, 14:lOl-111. J. Anim., 3.- the attack The a deal due the soil cditis and possible soil ctaminatis analyzed sam- il et F., de Zootech., 38: c à l ammiac de pailles de blé (niveau et Table 7. in cereal straws. Zootech., 38: à Oat Ash Silica Ca Na - - c S by ammiati. Anim. Feed Sci. Technol., 21: S. ti and extent lignificati affecting digestibility wheat and oat 7: Feed Sci. Technol., 26: INRA pp JUNG, GC., J. Anim. Sci., 57: cell wall phenolics. J. Anim. Sci., 57: JUNG, 36: J.

6 CIHEAM - Optis Mediterraneennes U.S., and compositi and site and extent disap by sheep. J. Anim. Sci.. 66: value Feed Sci. Technol., 21: du à l ammiac dans le effect and il the digestibility O. and AMAN, by GLC J. Food Chem., 26: W.J., 5. 47: theintake, digestibility and weight gain sheep and cattle diets. him O. and AMAN, In up digestibility. J. nol.,12: silica in F. A