Journal of the Grassland Society of Southern Africa, 1992
ABSTRACT The effect of calcium in the nutrient medium on kikuyu grass (Pennisetum clandestinum Ho... more ABSTRACT The effect of calcium in the nutrient medium on kikuyu grass (Pennisetum clandestinum Hochst), grown in a solution culture, was investigated. Calcium had no effect on the lignin content of leaf material, but decreased the lignin content per unit stem cell wall. Calcium appeared to have no significant effect on either the hemicellulose and cellulose content or on the ratio of constituent sugars of the hemicellulose fraction of both leaf and stem tissue. A high cell wall phenolic acid content in kikuyu leaves was associated with a high leaf calcium content. High calcium considerably increased the dry matter yield of kikuyu, but did not appear to improve its digestibility.
Journal of the Grassland Society of Southern Africa, 1990
ABSTRACT The non‐structural carbohydrates of kikuyu (Pennisetum clandestinum Hochst) seem to cons... more ABSTRACT The non‐structural carbohydrates of kikuyu (Pennisetum clandestinum Hochst) seem to consist mainly of sucrose. Total non‐structural carbohydrate content increased rapidly during the morning and reached maximum concentration in the afternoon. After sunset, the concentration decreased rapidly, reaching a minimum level by midnight. Low temperatures resulted in a significantly higher non‐structural carbohydrate content in all plant fractions than at warmer growth temperatures. Non‐structural carbohydrate concentrations were higher in stem tissue than in leaf material and the values were higher in 3‐week than in 6‐week regrowth. Die nie‐strukturele koolhidrate van kikoejoe (Pennisetum clandestinum Hochst) bestaan hoofsaaklik uit sukrose. Totale nie‐strukturele koolhidrate het vinnig toegeneem gedurende die oggend en het ‘n maksimum konsentrasie gedu‐rende die middag bereik. Na donker het die konsentrasie vinnig gedaal en ‘n minimum waarde is teen middernag bereik. Lae temperature het ‘n betekenisvol hoër nie‐strukturele koolhidraatinhoud in allé plantfraksies teweeggebring as hoër temperature. Nie‐strukturele koolhidraatkonsentrasies was hoër in die stingelweefsel as in die blaarmateriaal en die waardes was ook hoër in hergroei na drie as na ses weke.
ABSTRACT Milled grass particles were coated with n-alkanes and suspended in a xanthan gum solutio... more ABSTRACT Milled grass particles were coated with n-alkanes and suspended in a xanthan gum solution. Experiments snowed that grass particles could be coated uniformly with alkanes by means of a rotary evaporator. Further experiments showed that the grass particles, in stable xanthan gum suspension, could be accurately dispensed. The coefficients of variation of the alkane content per dose delivered by means of a dosing gun and syringe were 2·6 and 2·3%, respectively. There was no significant difference between the concentration of faecal alkanes derived from alkanes dosed in suspension-form and alkanes placed directly into the rumen.(Received March 10 1995)
Journal of the Grassland Society of Southern Africa, 1992
ABSTRACT The effect of calcium in the nutrient medium on kikuyu grass (Pennisetum clandestinum Ho... more ABSTRACT The effect of calcium in the nutrient medium on kikuyu grass (Pennisetum clandestinum Hochst), grown in a solution culture, was investigated. Calcium had no effect on the lignin content of leaf material, but decreased the lignin content per unit stem cell wall. Calcium appeared to have no significant effect on either the hemicellulose and cellulose content or on the ratio of constituent sugars of the hemicellulose fraction of both leaf and stem tissue. A high cell wall phenolic acid content in kikuyu leaves was associated with a high leaf calcium content. High calcium considerably increased the dry matter yield of kikuyu, but did not appear to improve its digestibility.
Journal of the Grassland Society of Southern Africa, 1990
ABSTRACT The non‐structural carbohydrates of kikuyu (Pennisetum clandestinum Hochst) seem to cons... more ABSTRACT The non‐structural carbohydrates of kikuyu (Pennisetum clandestinum Hochst) seem to consist mainly of sucrose. Total non‐structural carbohydrate content increased rapidly during the morning and reached maximum concentration in the afternoon. After sunset, the concentration decreased rapidly, reaching a minimum level by midnight. Low temperatures resulted in a significantly higher non‐structural carbohydrate content in all plant fractions than at warmer growth temperatures. Non‐structural carbohydrate concentrations were higher in stem tissue than in leaf material and the values were higher in 3‐week than in 6‐week regrowth. Die nie‐strukturele koolhidrate van kikoejoe (Pennisetum clandestinum Hochst) bestaan hoofsaaklik uit sukrose. Totale nie‐strukturele koolhidrate het vinnig toegeneem gedurende die oggend en het ‘n maksimum konsentrasie gedu‐rende die middag bereik. Na donker het die konsentrasie vinnig gedaal en ‘n minimum waarde is teen middernag bereik. Lae temperature het ‘n betekenisvol hoër nie‐strukturele koolhidraatinhoud in allé plantfraksies teweeggebring as hoër temperature. Nie‐strukturele koolhidraatkonsentrasies was hoër in die stingelweefsel as in die blaarmateriaal en die waardes was ook hoër in hergroei na drie as na ses weke.
ABSTRACT Milled grass particles were coated with n-alkanes and suspended in a xanthan gum solutio... more ABSTRACT Milled grass particles were coated with n-alkanes and suspended in a xanthan gum solution. Experiments snowed that grass particles could be coated uniformly with alkanes by means of a rotary evaporator. Further experiments showed that the grass particles, in stable xanthan gum suspension, could be accurately dispensed. The coefficients of variation of the alkane content per dose delivered by means of a dosing gun and syringe were 2·6 and 2·3%, respectively. There was no significant difference between the concentration of faecal alkanes derived from alkanes dosed in suspension-form and alkanes placed directly into the rumen.(Received March 10 1995)
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