A study is reported on the intake and digestibility of two varieties of Guinea grass (Panicum maximum) var. Serdang and Coloniao fed in the long form in balance studies using goats and sheep. Five balance studies for each variety were completed, each lasting for 21 days, a 14-day adaptation period being followed by a 7 day collection period. The grasses were fed at five stages of growth: 16-19, 21-28, 28-35, 35-42, 42-49 days. The chemical composition of the grasses decreased with increasing maturity due to growth. The crude protein contents on dry matter basis were 21.8 and 20.0, 16.7 and 16.7, 13.2 and 14.7, 12.5 and 14.5 and 11.5 and 11.9 per cent for Serdang and, Coloniao at the five stages of growth respectively. The corresponding gross energy contents on dry matter basis were 16.8 and 16.9, 16.6 and 16.5, 16.5 and 16.4, 16.1 and 16.1, and 14.9 and 16.1 MJ/kg. respectivelyth; the chemical composition was higher in vat. Coloniao compared to Serdang. Statistically significant difference were noted (P<0.05) between species between trials and interaction in the daily voluntary dry matter intake of fresh grass and dry matter. For both grasses goats recorded a higher digestibility of the proximate components compared to sheep. The digestibility of dry matter for goats and sheep for var.Serdang were 73.0 and 70.4, 68.3 and 66.7, 69.1 and 66.5, 69.7 and 65.6, 66.7 and 62.1, and for var. Coloniao 74.6 and 68.8, 72.4 and 68.4, 72.1 and 64.1, 64.3 and 60.0 and 61.2 and 58.5 per cent at 16 19 days stage of growth. Statistically significant differences (P<0.05) between goats and sheep were only noted for var. Coloniao in dry matter digestibility at 28-35 days growth. By comparison,for var. Serdang,significant differences (P<0.05) were noted in nitrogen-free extract at 21-28, and crude fibre digestibility at 35-42 and 42-49 days growth respectively.The results demonstrate a higher digestive efficiency in goats compared to sheep. The digestible energy (D.E.) content in the grass varieties were 6.70 to 10.19 (MJ/kg.) 4.19 and 7.37 (MJ/kg.) and D.C.P. values 1.0 to 2.3 per cent and 1.4 to 2.8 per cent for goats and sheep respectively. These suggested that at the five stages of growth studied,both varieties of grass had adequate D.E. to support maintenance and some production, while the N requirements for maintenance would only be adequate from the grass varieties up to 35 days growth. It is suggested that with increasing maturity of the grass, goats tend to digest the crude fibre component much better than do sheep. 

Full Text ( 1.4 MB )