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Silage quality, dry matter
intake and digestibility by West African dwarf sheep of
Guinea grass (Panicum maximum cv Ntchisi) harvested
at 4 and 12 week regrowths
O. J. Babayemi
Department of Animal Science, University of Ibadan, Nigeria.
E-mail:
oj.babayemi@mail.ui.edu.ng.
Accepted
2 June, 2009 |
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An all year round pasture is not always guaranteed in the
tropics especially in Nigeria as half of the period is a dry
season. In order to circumvent the pasture scarcity during
drought, silage making is paramount. In this vein, nutritive
value of silage made from Guinea grass (GG) frequently
harvested at 4 and 12 week regrowth was assessed by West
African dwarf (WAD) sheep. Four weeks GG (4WGG) and 12 weeks
GG (12WGG) were mixed to make treatments: 12 week GG
(12WGG), 4 week GG (4WGG), 25% 4WGG + 75% 12WGG, 50% 4WGG +
50% 12WGG and 75% 4WGG + 25% 12WGG. Grass mixtures were
subjected to silage for 42 days. Quality and chemical
composition of the silage was assessed. Silage was also fed
to WAD sheep to determine the dry matter intake (DMI) and
dry matter digestibility (DMD). Crude protein for 4WGG was
17.5% higher than that of 12WGG. Silage colour was normal
except for 12WGG that showed light yellow. The pH value and
temperature ranged from 4.2 - 5 and 25 - 27.5ºC,
respectively. Pleasant and firm textures of the silages were
observed irrespective of the age of the grass and the ratio
of mixtures. The DMI significantly ranged from 617.2 g in
4WGG to 759.1 g in 50% 4WGG + 50% 12WGG. Variation occurred
in DMD among the sheep ranged from 61.8 in 12WGG to 73.5 in
75% 4WGG + 25% 12WGG. Results showed that silage quality was
better and that dry matter intake and digestibility were low
by the sheep fed 4 or 12 week grass regrowth but the animals
performed well at different combinations of grasses,
suggesting an effective utilization of both young and
fibrous grasses.
Key
words:
Silage quality, chemical composition, intake and
digestibility, Sheep, Guinea grass. |
