Chemical composition and nutritive value of four varieties of cassava leaves grown in South-Western Nigeria.

The nutritive value of leaves of four varieties of cassava - MS 6, TMS 30555, Idileruwa and TMS 30572 was evaluated based on their chemical composition and in vitro fermentation. Crude protein (CP) contents of cassava leaves ranged from 177 to 240 g/kg dry matter (DM), with TMS 30555 showing the highest CP contents. Neutral detergent fibre (NDFom) and acid detergent fibre (ADFom) contents of cassava leaves ranged from 596 to 662 and 418 to 546 g/kg DM respectively. Condensed tannin (CT) and hydrocyanic acid contents ranged from 1.0 to 3.8 g/kg and 58.5 to 86.7 mg/kg DM respectively. The range of volatile fatty acids (VFA) in the supernatant after in vitro incubation of the cassava varieties was: acetate (14.7-31.5 mmol/l); propionate (4.5-6.3 mmol/l); butyrate (3.1-3.9 mmol/l); valerate (0.4-0.6 mmol/l); iso-butyrate (0.6-1.3 mmol/l); iso-valerate (1.1-1.9 mmol/l). The acetate:propionate ratio resulting from fermentation of TMS 30555 was higher(p < 0.05) than that of the other leaves. The highest in vitro gas production of 50.5 ml/200 mg DM was recorded for MS6 being higher (p < 0.05) than for TMS 30572, but similar to TMS 30555 and Idileruwa. The DM, CP, ADF and HCN contents of cassava leaves were positively correlated with gas production, while CT content was negatively correlated with gas production. The study showed that leaves of the varieties MS 6 and TMS 30555 are superior to the others in terms of CP and gas production indicating a higher digestibility and energy content and thus nutritive potential. They may therefore serve as supplements for ruminants fed on poor roughages.

Chemical composition and in sacco degradability of four varieties of cassava leaves grown in Southwestern Nigeria in the rumen of sheep.

The nutritive value of leaves of four varieties of cassava (MS 6, TMS 30555, Idileruwa and TMS 30572) were studied through analysis of their chemical components and degradability of their dry matter (DM) and crude protein (CP) in the rumen of sheep. Results of the chemical analyses showed that the leaves of the four varieties contained different proportions of organic matter which was significantly (P < 0.05) highest in TMS 30572 with value of 935 g/kg DM, while CP (gram per kilogramme DM) was significantly highest in TMS 30555 (240), followed by MS 6 (235), TMS 30572 (208) and least in Idileruwa (177). Mean metabolisable energy (megajoules per kilogramme DM) was significantly (P < 0.05) highest in TMS 30572 (8.2) and similar with Idileruwa (8.0) but different from TMS 30555 and MS 6, respectively (7.8 and 7.6). The mineral contents (gram per kilogramme DM) showed that leaves of MS 6 and Idileruwa had the highest concentrations of K (2.86) and a significantly lowest value (1.83) in TMS 30555. Also, the highest concentration of Ca and Fe (6.81 and 6.23) was recorded in MS 6. The highest Ca:P of 3.20 was obtained in TMS 30555. DM degradation characteristics and effective degradability varied significantly (P < 0.05) and were consistently highest in TMS 30572. The washing loss (a) ranged from 15.9% in MS 6 to 21.3% in TMS 30572. TMS 30572 tended to have higher (P = 0.546) insoluble but fermentable fraction (b) than all other varieties. Moreover, the potential degradability (a + b) tended to be higher (P = 0.041) in TMS 30572 (69.5%) followed by TMS 30555 (67.1%) and the lowest was in Idileruwa (42.7%). The highest effective degradability was recorded in TMS 30572 (63.9%) and the lowest in Idileruwa (40.7%). The degradation rate constants (c) of Idileruwa was significantly higher (P = 0.001) than those of MS6, TMS 30555 and TMS 30572. The results generally indicated that the leaves could be ranked for their potential feeding value as TMS 30572 (71.5%) > MS6 (65.8%) > Idileruwa (63.0%) > TMS 30555 (50.4%). It is therefore concluded from this study that leaves of TMS 30572 and MS 6 have good potential as feed resources for ruminant animals and could be used in ruminant feeding as protein source ingredient.

The effect of stocklength, stock diameter and planting angle on early establisment of Gliricidia sepium.

Legume tree crops, which establish easily and do not require extensive agronomic inputs, constitute potentially valuable sources of supplementary feeds that subsistence and medium-scale livestock farmers in the tropics could use to improve livestock nutrition and productivity. A field trial was conducted with Gliricidia sepium cuttings to investigate the effect if three stock lengths (20, 30 and 40 cm), two stock diameters (1.5-2.5) and (3.0-3.5 cm) and three planting angles (30 degrees, 60 degrees and 90 degrees) in a factorial experiment. There were high significant differences (p < 0.05) in all the growth parameters of the stock diameters and stock lengths used. The highest dry matter yield of 3.83, 4.61 and 4.65 t ha(-1) were produced by stock length 20, 30 and 40 cm, respectively. The highest planting angle of 90 degrees produced the tallest shoot height and biggest basal diameter, while the least planting angle of 30 degrees produced the least shoot height and basal diameter, respectively. The interactions between the smaller stock diameter and the least planting angle (30 degrees) produced the least values of growth parameters. Gliricidia cuttings could be easily established with thicker stock diameter of not less than 3.0 and 40 cm stock length, planting in an angle between 60 and 90 degrees.