IDENTIFICATION, PREFERENCE AND NUTRITIONAL EVALUATION OF ACACIA SPECIES AS BROWSE FEED FOR GOATS IN ASAL REGION, BARINGO COUNTY - KENYA

Abstract

The pastoralist communities in the ASAL regions of Sub-Saharan Africa face significant constraints arising from insufficient nutritious livestock feeds, which in turn limits livestock productivity. Nonetheless, grass, shrub bushes and fodder trees are primary feed resources for livestock in a wide range of production practices. This study sought to identify and evaluate the nutritive value of five common Acacia browse species; A. brevispica, A. senegal, A. tortilis, A. mellifera and A. nilotica in Marigat sub-county, Baringo County. The study examined the preference rating of Acacia spps, among goats. Their nutritive value was determined by proximate analysis using AOAC (1995) on DM basis of leaves, bark and pods and reported in percentage content as DM, CP, CF, Ash, EE. The In-vitro DM degradability (IVDMD) was also determined and measured by 200 mg dry matter in duplicates at 39.20 C after, 0, 3, 6, 9, 12, 24, 48, 72, 96 and 120h of incubation and fitted to the exponential model, GP(t) = a + b(1 – e-c(t – L)). The statistic, Kruskal-Wallis, H test, (χ2 (4) = 182.6) at 0.05 significance levels indicated significant differences in preferences between the Acacia spps. A. brevispica being ranked the highest in preference while A. senegal ranked the lowest. ANOVA results, F (4, 475) = 62.61, p<0.05 showed significant differences in browsing preference. A. brevispica was highly preferred while A. senegal was least preferred. Results of proximate analysis indicated that DM was high for all samples and ranged from 97.21% in A. nilotica leaves to 94.13% in A. tortilis pods. The CP ranged from 23.9% in A. senegal pods to 2.76% in A. nilotica bark while CF ranged between 43.18 % in A. Senegal bark, to 9.66% in A. nilotica leaves, EE ranged between 5.21% in A. nilotica leaves to 0.31% in A. nilotica bark. Lastly, the IVDMD analysis indicated that A. nilotica leaves had highest gas production followed by A. mellifera and lastly A. brevispica. A. mellifera pods were highly degradable followed by A. nilotica, and lastly, A. tortilis. A. nilotica bark was highly degradable followed by A. senegal, and lastly A. tortilis bark. There were significant differences in the degradability of Acacia spps(p ≤ 0.05) with A. nilotica leaves, A. brevispica pods and A. nilotica bark being highly degradable. Based on the statistical results, the study rejected all the null hypotheses and concluded that some Acacia spps have comparable nutritive value that may meet the feeding requirements of the browsers. The study recommends that A. nilotica A. brevispica and A. tortilis be developed for use in feeding goats in the arid and semi – arid regions. Further studies on anti-nutritional factors and Animal Response Trials for production values needs to be done.