Efficacy of albendazole against nematode parasites isolated from a goat farm in Ethiopia: relationship between dose and efficacy in goats

A suspected case of albendazole resistance in a goat farm of Hawassa University was examined using faecal egg count reduction test (FECRT), controlled anthelmintic efficacy test and egg hatch assay (EHA) to verify the development of resistance and/or the need for higher doses of the drug in goats than in sheep. The experiment was conducted in 12 sheep (2 groups: treatment versus control) and 24 goats (4 groups: 3 treatments versus control, n = 6; per group) following artificial infection with infective larvae of Haemonchus contortus and Oesophagostomum columbianum. The first group of sheep and goats were treated orally with albendazole at the dose rate of 3.8 mg/kg body weight (i.e. manufacturer's recommended dose for sheep) while the second group of sheep and the fourth group of goats were left untreated. The second and the third group of goats were treated with albendazole at 5.7 and 7.6 mg/kg respectively. The FECRT showed an efficacy of albendazole in goats to be 65.5, 81.4 and 84.1% at the dose rate of 3.8, 5.7 and 7.6 mg/kg body weight respectively while in sheep it was 62% at the dose rate of 3.8 mg/kg. Increasing the dose to 1.5 the sheep recommended dose induced minor improvement of efficacy in goats; however the efficacy was almost the same at 1.5 and twice the dose recommended for sheep. Worm counts at day 15 post-treatment revealed that H. contortus has developed resistance to albendazole. EHA results also supported these findings. On the other hand, O. columbianum was 100% susceptible at all dose levels tested.     

Development of Chemical Index as a Measure of In-Stream Water Quality in Response to Land-Use and Land Cover Changes

Water pollution in response to accelerated land-use/land cover changes has drawn concerns because of public health and environmental impacts. The study was conducted to evaluate the impact of land use/land cover changes, seasonal, and location on water quality of streams within the Wheeler Lake Watershed basin in northern Alabama. Temporal water samples from 18 sheppard streams were randomly collected in 2000 and 2001, processed and analyzed for pH, and total nitrogen (TN), dissolved (Dp), particulate (Pp) and total phosphorus (Tp), dissolved oxygen (DO) and soluble lead (Pb) concentration, employing standard methods of analysis. The data were normalized and integrated into a simple index (WQC_Index) to evaluate stream water quality. Results showed that the urban proportion of the total watershed basin had increased from 2.9 to 14.7% with an associated loss of agricultural (8.9%) and wetland (4.8%) covers from 1992 to 2000. A change in land-use/land covers in association with seasonal and location variation significantly affected stream water quality. Total nitrogen concentration in stream water had a peak during the summer at 34% above the annual mean. While both Pp and Tp concentrations peaking during the summer at 24% above the annual mean and about 25% below the annual mean during spring, the DO concentrations were 46% above the annual mean during the fall and 18 to 26% below annual mean during summer. The WQC_Index had responded very seasonal and showed significant identical trends, with 21% degradation in water quality during the summer above the annual mean and improvement during the spring at 20% above the annual mean. Upstream water had a significantly greater Pp and Tp (21 to 28%) concentration than at down- and middle streams water. Location and seasonal variations had significant interactive effects on Pp, Tp and DO concentration of stream water. Total amount of seasonal rainfall significantly accounted 99.6% of the variations in WQC_Index. Increasing seasonal mean relative humidity, air and soil temperature, evaporation and solar radiation had positive relationship with the variations in WQC_Index. Among the water quality parameters, both Pp and Tp were correlated (r ² = 0.998^?*?) to each other, and accounted for more than 80% variability of the WQC_Index. Highly significant positive linear relationship between Pp and Tp concentration suggested that 99.8% of the P in stream water is in Pp form which probably transported with sediments in surface runoff. In other words, Pp is the main pollutant responsible for degradation of stream water quality in the Wheeler lake basin. Routine measurement of either Pp or Tp concentration could be used as sensitive and early indicator of temporal changes in stream water quality even when the other parameters changed negligibly or remain unchanged.     

Livestock Feed Marketing in Ethiopia： Challenges and Opportunities for Livestock Development

This paper presents the feed marketing systems of Ethiopia in terms of feed demand and supply, feed quality issues, feed prices and price trends based on qualitative data generated through rapid market appraisal methodology. The results indicate that, the demand for roughages, agro-industrial by-products （AIBP） and compound feeds is showing increasing trend. The use of feed from commercial sources is, however, very limited due to shortage of feed supply and inefficient marketing system. The AIBP mainly from flour and grind mills, oil processing plants and breweries are in short supply and directly marketed to user or through traders. Consequently, most of the exiting feed mixers/processing enterprises are operating under capacity estimated at about 20%-30%. The main marketed roughages, which are mainly cereal straws and baled hay, are also in short supply. Feed prices are increasing from time to time and mainly exacerbated by the increasing trend in export market of AIBP and double taxation in mixed rations. There is no any feed quality control or assurance mechanism in Ethiopia. Precaution needs to be taken in the area of taxation in order to avoid double taxation. Implications to improve the feed marketing systems and opportunities for livestock development are drawn.     

Diversity,regeneration status and population structure of gum- and resin-bearing woody species in south Omo zone,southern Ethiopia

South Omo Administrative Zone in Ethiopia is home to 18 indigenous ethnic groups whose livelihood is vulnerable due to recurrent drought and degradation. Despite the preliminary observation showing the rich dry-forest resource base that, if sustainably managed could enhance livelihoods and biodiversity conservation, there is lack of empirical data on its current status. We conducted a study aiming at quantifying the population status of gum- and resin-bearing species in two randomly selected districts, Hamer and Bena-Tsemay. Seventy-five quadrats(35 at Hamer and 40 at Bena-Tsemay) each measuring 400 m2 were established along line transects to assess species diversity and equitability, density, frequency, dominance, importance value and population structure. We recorded a total of 27 woody species of 12 families and 14 genera. Fifteen species(9 at Hamer and 14 at Bena-Tsemay) of the genera Acacia, Boswellia, Commiphora and Sterculia, were identified as either major sources of commercial gums and resins or their adulterants. Gum- and resin-bearing species comprised 56% and 57% of species richness, 48% and 50% of total density per ha, 95% and 98% of basal area, and 64% and 56% of importance values at Hamer and Bena-Tsemay, respectively. Diversity of the entire woody species assemblage and of the gum- and resin-bearing species was slightly higher at Bena-Tsemay(H= 2.61, 1.4) than at Hamer(H′= 2.48, 1.28), respectively. The diversity and abundance of the resource base suggest potential for development of value-added commercialization of gum and resins to enhance livelihoods and encourage sustainable management of the forest at these study areas. We recorded, however, declining natural regeneration of most gum- and resin-bearing species, and this calls for integrated and participatory species management and landscape rehabilitation.     

Species-specific allometric equations for improving aboveground biomass estimates of dry deciduous woodland ecosystems

Allometric equations are important for quantifying biomass and carbon storage in terrestrial forest ecosystems.However,equations for dry deciduous woodland ecosystems,an important carbon sink in the lowland areas of Ethiopia have not as yet been developed.This study attempts to develop and evaluate species-specific allometric equations for predicting aboveground biomass(AGB)of dominant woody species based on data from destructive sampling for Combretum collinum,Combretum molle,Combretum harotomannianum,Terminalia laxiflora and mixed-species.Diameter at breast height ranged from 5 to 30 cm.Two empirical equations were developed using DBH(Eq.1)and height(Eq.2).Equation 2 gave better AGB estimations than Eq.1.The inclusion of both DBH and H were the best estimate biometric variables for AGB.Further,the equations were evaluated and compared with common generic allometric equations.The result showed that our allometric equations are appropriate for estimating AGB.The development and application of empirical species-specific allometric equations is crucial to improve biomass and carbon stock estimation for dry woodland ecosystems.     

Impacts of participatory forest management on forest conditions: Evidences from Gebradima Forest,southwest Ethiopia

ABSTRACT

This study examines a participatory forest management program and its impacts on forest conditions in Gebradima Forest, southwest Ethiopia. Vegetation data were collected from both participatory forest management (PFM) and nonparticipatory forest management (non-PFM) forest blocks. A total of 54 plots (27 from each forest block) measuring 20 m × 20 m were employed to collect species composition and structural data. Results indicated that a total of 51 different woody plant species (49 at PFM and 43 at non-PFM blocks), representing 31 families were recorded, with 41 species were shared for both forest sites. Species diversity and evenness were higher in the forest with PFM (H´ = 3.29, E = .85) compared to the forest without PFM (H´ = 2.97, E = .79). The overall mean values of tree/shrub and seedling density per hectare, diameter class (≤ 20 cm) were also significantly (p < .05) higher in PFM forest than non-PFM forests. However, no significant variations were observed in sapling density per hectare and basal area between the two studied forest blocks. It can be concluded that PFM had a positive effect on forest conditions compared with a similar forest without PFM. Hence, it is important to scaling up PFM in neighboring forests.     

Comparative availability to wheat of metals from sewage sludge and inorganic salts

A greenhouse experiment was conducted to evaluate the availability of metals from sewage sludge and inorganic salts, and the effect of pH and soil type on yield and metal (Zn, Cu, Cd and Ni) uptake by wheat (Triticum aestivum L. var. ‘holly’). Soils used in this study were Hartsells sandy loam (fine-loamy, siliceous Thermic Typic Hapludult) and Decatur silty clay loam (Clayey, kaolinitic, Thermic Rhodic Paleudult). Two treatments of sewage sludge containing metals were applied at the rate of 20 and 100 mt ha^?1. Inorganic Salts of Zn, Cu, Cd, and Ni were applied (as sulfate salts) at concentrations equivalent to those found in the 20 and 100 mt ha^?1 sludge. One treatment consisted of inorganic metals plus sewage at the 20 Mg ha^?1 rate. Two soil pH levels, one at field pH (below 6.0) and another pH adjusted between 6.5 and 7.0 were used. Wheat plants were harvested four weeks after germination. Two more subsequent harvests were made at four week intervals. For each harvest, dry matter yield increased as the rate of sludge application increased for both soil types. The soil pH also influenced the dry matter yield. High yield was observed when the pH was adjusted between 6.5 to 7.0 for both soils. An increase in yield was also observed at each subsequent harvest for most of the treatments. Inorganic salt treatments produced lower dry matter yields when compared with the sludge. Both sludge application and metal salts increased plant tissue concentration of Zn, Cu, Cd, and Ni at field pH for both soils. However, increasing the pH of the soil for both sludge and inorganic salt treatments generally decreased the tissue concentration of the above metals.     

Black Sigatoka leaf streaks of banana (Musa spp.) caused by Mycosphaerella fijiensis in Ethiopia

Journal of Plant Diseases and Protection - Sigatoka leaf streaks caused by Mycosphaerella spp. are the most destructive fungal diseases of bananas and plantains throughout the world. The disease is...     

Study of heritable variation and genetics of earliness in mungbean (<Emphasis Type="Italic">Vigna radiata</Emphasis> L. Wilczek)

Fifty-five mungbean lines were evaluated for days to maturity and grain yield per plant. This material showed considerable range of variability for the target traits. Eight genetically diverse parents were selected and used for a full diallel set of crosses to study the mode of inheritance for earliness related parameters (days to flowering, days to maturity and length of reproductive phase) during summer 2005. The F₁ generation of these crosses was sown during the spring of 2006 and the selfed seeds were used to raise the F₂ generation during kharif season. The data recorded from two generations were subjected to genetic analysis. The formal ANOVA showed the significance of both additive and dominance effects for all the traits in both generations. Significance of D, H₁ and H₂ components also confirmed the contribution of both additive and dominance effects in controlling the inheritance of these traits. The estimates of narrow sense heritability were low to moderate except higher estimates for days to maturity in F₂ generation, while the broad sense heritability estimates were relatively higher. Seasonal and environmental effects were also found to be significant. In view of the complex nature of gene action for earliness, it is suggested that breeders should look for transgressive recombinants of earliness and other desirable attributes in later segregating generations to gain higher genetic advance. The variety NM92 was found to be the best source of earliness in mungbean breeding.