Title : Effect of cutting frequency on forage yield and nutritive quality of Brachiara grass cultivars in coastal lowlands, Kenya
Abstract:
Feed shortage during dry season limits productivity of livestock in the Coastal lowlands, Kenya. A study was carried out at Kenya Agricultural and Livestock Research Organization, Mtwapa and Msabaha Centres in Coastal lowlands. Grass cultivars were Brachiaria brizantha cvs. Marandu, Xaraes, Piata and MG-4, Brachiaria decumbens cv. Basilisk, Brachiaria hybrid cv. Mulato II and Brachiaria humidicola cv. Llanero evaluated along Chloris gayana cv. Ex-Tozi as a control. Plant number, plant height, tiller number and dry matter (DM) yields were monitored at 6, 8 and 12 weeks’ intervals in the year 2014 and 2015. Analysis of variance was taken to determine yield and nutritive quality using statistical analysis systems (SAS). At Mtwapa, increase in cutting interval from 6 to 8 weeks increased DM yield but further increase to 12 weeks, the yield declined. Moreover, at Mtwapa, Mulato II and Piata recorded the highest dry matter (7.2 and 7.0 t ha). At Msabaha, Basilisk had (5.0 t ha) DM in 2014 long rains. High crude protein were observed at 6 and 8 weeks than at 12 weeks but not significantly different (p< 0.05) from Rhodes grass ex-Tozi while mulato II had 6.1%. Cultivars; Basilisk, MG-4, Piata and Llanero had higher nutritive value and were more productive than Rhodes grass. Although all the cultivars established had potential as animal feed, Xaraes, Basilisk, MG-4 and Mulato II established well in terms of plant population and biomass yield. They had capability to grow at low rainfall, maintain high yield and showed outstanding potential as forage plant especially in lowland areas. The DM was influenced by the tiller number and plant height during the long and short rains. It is recommended that Xaraes, Basilisk, MG-4, Piata and Mulato II, the best performing cultivars, be harvested at 8 weeks’ interval to maximize production and nutritive quality. Further research should be conducted to determine the suitable defoliation height for Brachiaria species and feeding trial to assess animal gains since the results showed that the Brachiaria grass have high nutritive quality