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41.
Tadesse Eguale Hassen Chaka Daniel Gizaw 《Tropical animal health and production》2009,41(7):1267-1273
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. 相似文献
42.
Tazebchew Asres Daniel Tadesse Tesfaye Wossen Assefa Sintayehu 《Journal of Crop Science and Biotechnology》2018,21(5):451-457
Lack of suitable malt barley varieties that exhibit high yielding, stable performance, and good malting quality is the major factor among several production constraints contributing to low productivity of malt barley in the North Gondar Zone. The present study was done to evaluate and recommend the best performing varieties in the major potential areas of North Gondar. The experiment was conducted at three locations for two consecutive years (2015 and 2016) during the main cropping season using twelve improved varieties. The design was randomized complete block design with three replications. Analysis of variance and GGE [genotype main effect (G) and genotype-by-environment interaction (GE)] biplot analysis were conducted following their respective procedures. Combined analysis of variance revealed a highly significant difference (P < 0.01) among genotypes, environments, and genotype-by-environment interaction for grain yield, most agronomic and malt quality traits. All the varieties had acceptable malt quality traits. The variety IBON-174/03 was found to be the highest yielding and the most stable variety across environments. According to the polygon view of biplot analysis, the varieties were spread across four sections and the test environments spread across two sections. Among the six test environments, D and C were more discriminating and F and B were less discriminating. Test environments F, E, and A were found to be more representative of the mega-environment than D. Considering early maturity, malt quality, grain yield, and stability performance; it is recommended to use the variety IBON-174/03 for production in the study areas and in similar areas. 相似文献
43.
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... 相似文献
44.
A cross-sectional study was carried out from November 2008 to February 2009 in Guraferda and Sheko districts of Bench Maji
Zone, South Western Ethiopia. The objective of the study was to determine the prevalence of bovine trypanosomosis and the
density of its vectors. An overall prevalence of trypanosome infection in the study area was 4.4%. Trypanosoma congolense (36.36%) was the dominant trypanosome species followed by Trypanosoma vivax (18.18%) and Trypanosoma brucei (9.09%). Mean packed cell volume value of parasitemic animals (21.8%) was significantly (P < 0.05) lower than that of aparasitemic animals (27.7%). Biconical and NGU traps were deployed for 72 h, and the result indicated
Glossina pallidipes followed by Glossina fuscipes as the only tsetse fly species caught in the study area along with other biting flies like Stomoxys and Tabanus. The apparent density of tsetse flies was 2.83 flies trap−1 day−1. NGU trap caught more of G. pallidipes while biconical trap caught more G. fuscipes, and the difference was significant (P < 0.05). Although the current study indicated low prevalence of trypanosomosis in the study area, the impacts of trypanosomosis
on cattle production and productivity should not be neglected. Therefore, attention should be given to control the disease
and also the vector. 相似文献
45.
Amsalu Abich Tadesse Mucheye Mequanent Tebikew Yohanns Gebremariam Asmamaw Alemu 《林业研究》2019,(5):1619-1632
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. 相似文献
46.
47.
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. 相似文献
48.
Comprehensive analysis of food webs requires identifying dietary sources that support the production of all major organisms within the food web/food chain. Here, we use stable isotope ratios (δ13C, δ34S and δ15N) to assess the relative contribution of different basal carbon sources to the diet of Nile tilapia (Oreochromis niloticus L.) in three tropical lakes Hawassa (also Awasa in literature), Ziway and Koka (Ethiopia). Computations were carried out with Stable Isotope Analysis in R (SIAR) model to quantify the dietary proportion of each prey for the tilapia fish. Basal food sources were distinguishable based on their δ13C, δ34S and δ15N values. In Lake Ziway, macrophytes (64%) were the dominant assimilated diet of tilapia while particulate organic matter (POM) and zooplankton contributed only 20% and 16%, respectively. In parallel, Nile tilapia in Lake Hawassa assimilated macrophytes (35%), POM (33%) and zooplankton (32%) at comparatively equal proportion. The dietary sources of the fish in Lake Koka were POM (49%) and zooplankton (51%). In contrast with earlier studies based on gut content analysis, the present results reveal that macrophytes contributed more and phytoplankton less than previously reported especially in macrophyte‐dominated lakes Ziway and Hawassa. The ecological condition of the lakes might have been predominantly accountable for the diet change of the tilapia. As dietary data are prerequisite for food web/food chain analysis and aquaculture industry, re‐evaluating the diet of aquatic organisms appear relevant. 相似文献
49.
Bezie Yilkal Tilahun Tadesse Atnaf Mulugeta Taye Mengistie 《Journal of Crop Science and Biotechnology》2021,24(3):229-244
Journal of Crop Science and Biotechnology - The search for technologies for crop improvement has been a continuous practice to address the food insecurity to the growing human population with an... 相似文献
50.