ABSTRACT

To have higher profits and sustained production of livestock it is important to understand the biomass accumulation and growth rate of the forages the animals feed on. This project work looked into the growth and biomass accumulation of forage maize (Zea mays), forage millet (Echinochloa uti/is), elephant grass (Pennisetum purpereum) and garnba grass (Andropogon gayanus).

The experiment was conducted at a location within Federal University Oye-Ekit, Ekiti State, Nigeria with Latitude - N 07° 48.308, Longitude - E 005° 29.573 and 548.4m above groul!d level with an annual rainfall of 1778mm. The planting was done using completely randomized design (CRD) in 4-rows with 4 replicates. The soil used for this study contained a high organic matter before planting (49.96%) and after harvesting was completed (33.59%). The soil used in planting belonged to the Loam soil category. The highest growing grass in terms of plant height and sward height was Pennfnsetum purpereum throughout the period of carrying out this experiment.

Zea mays had the largest leave width (5.44cm at 8weeks) as well as the highest number of leaves during the experiment. At the end of 8weeks; Zea mays had the highest biomass accumulation of 114%, Echinochloa uti/is had a biomass accumulation of51.31%.

Andropogon gayanus had a biomass accumulation of 45.53%, Pennisetum purpereum had a biomass accumulation of 44.32%.

Samples from the last cuttings (8th week) had the highest crude protein content (11.88% in Andropogon gayanus) although there was no significant differences between the crudr prntein levels of the different species statistically (p <=0.05). Crude protein was found to increase nearly linearly as the grasses grew. The crude fibre content of the three grass species was observed to undulate as the grasses grew although there was no significant difference between the species. The highest fibre content was observed in the 6th week (13.58% in Zea mays of cutting due to encrustation of lignin in them as the grasses matured. The crude Ash content did not vary between the four grass species statistically (p <= 0.05). Although the highest crude ash content was recorded in the 6th week (5.80% in Andropogon gayanus). The crude fibre, moisture content and the fat content all followed the same irregular patterns and there was no significant differences between their percentage compositions in all the plant samples.

Keywords: Zea mays, Echinoch/oa uti/is, Pennisetum purpureum, Andropogon' gayanus, Growth rate model, Biomass accumulation model, proximate composition.