Effect of Variety on Proportion of Botanical Fractions and Nutritive Value of Different Napiergrass (Pennisetum purpureum) and Relationship between Botanical Fractions and Nutritive Value

Abstract

Five varieties of napiergrasses (Pennisetum purpureum) were fractionated botanically into leaf blade, leaf sheath, stem and head. Chemical composition of each of whole napiergrass and their botanical fractions were determined. Correlation, linear and multiple regressions between botanical fractions and nutritive value of varieties of napiergrass were also estimated. All botanical fractions differed due to the effect of variety. Napier Pusha contained the highest proportion of leaf blade and internode, but the lowest proportion of leaf sheath. Napier Hybrid contained the lowest proportion of leaf blade, but highest proportion of node. Consequently, napier Pusha contained the highest (p<0.01) crude protein (CP, 9.0%), but Napier Hybrid had the lowest CP (7.0%). Chemical composition of whole plant differed significantly (p<0.01; except NFE, p>0.05) due to the variety. Not only the whole plant, chemical composition of most botanical fractions of whole plant differed (p<0.05 to 0.01) due to the variety. The intrarelationships between leaf blade and leaf sheath was negative (r=-0.43). Leaf sheath was also negatively correlated to CP, but positively correlated to ash of whole Napier or their botanical fractions. Leaf blade, on the other hand, increases CP but decreases ash content of whole plant or their fractions. These results, therefore, suggest that napiergrass varieties differ widely in terms of botanical fractions and nutritive value, which may have important implications on intake and productivity of animals. Furthermore, napiergrass varieties should be selected for leaf blade only for a better response.

Nutritive value of selected grasses in North Sumatra, Indonesia

“…(2004a). The wide variation in the CP and fiber contents of the forages were consistent with previous reports (Fariani 1996; Tudsri & Kaewkunya 2002; Islam et al . 2003; Nasrullah et al .…”

Minerals profile of forages for grazing ruminants in Pakistan

“…The native and un improved pasture forages had lower levels of Mg than most species of forages and grasses However, differences in the content of Mg in this study with those in the literature could be partly explained by differences between forage species, level of Mg in the soil, influences of locality and climate, growth stage, proportion of leaf and stem fractions collected for mineral analysis, and season when forage sampling was done. The grazing pasture forages had slightly higher levels of Mg than the recommended requirement [25,43]. These forages would therefore meet the theoretical requirement of Mg for beef cattle and for lactating cows (1.2 -2.1 g/ kg DM) [50].…”

“…An excess of chloride may influence calcium metabolism and cause excessive excretion and a calcium deficiency may occur. An excess of sulfates may interact with selenium and can cause a selenium deficiency [25]. Also, when there is a calcium deficiency, toxicosis from all minerals, essential and non-essential, is more likely to occur.…”

Opportunities for Napier Grass (Pennisetum purpureum) Improvement Using Molecular Genetics

“…Nutritional quality is strongly influenced by management practices and age at harvest but, on average, Napier grass is considered to contain 9% CP, 20% DM, 70% NDF, 50% ADF, 9% ash and 6% lignin in samples taken from 10-15 week old plants [74,75]. Apart from genetics, the nutritional qualities of forages are influenced by many factors including the climate [76], soil nutrition [77], season and grazing pressure [78], management [65,79,80] and fertilizer application [81].…”