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81.
Endashaw Bekele Mulatu Geleta Kifle Dagne Abigail L. Jones Ian Barnes Neil Bradman Mark G. Thomas 《Genetic Resources and Crop Evolution》2007,54(7):1419-1427
Complete sequences for the internal transcribed spacers of the 18s–26s nuclear ribosomal DNA were generated to establish phylogenetic
relationships among five species of the genus Guizotia. Parsimony analysis and pairwise distance data produced a single tree with four clearly distinguished clades that accord
with previously reported chromosomal data. The clades produced here have been discussed with reference to existing taxonomic
treatments. It appears that Guizotia scabra ssp. scabra, G. scabra ssp. schimperi and Guizotia villosa have contributed to the origin of Guizotia abyssinica, the cultivated species of the genus. The present composition of the species of genus Guizotia and the subtribe the genus presently placed in are suggested to be redefined. 相似文献
82.
Hadush B Eshetu L Mengistu W Hailesilassie M 《Tropical animal health and production》2009,41(5):803-806
A cross sectional study was conducted to determine the sero-prevalence of contagious caprine pleuroneumonia in three districts
of Tigray and Afar regions of Ethiopia namely; Kefta Humera, Alamata and Aba-‘alla. Proportions and chi-square test statistics
were used to analyze the data. From a total of 863 goats and 137 sheep tested, 282 (32.68%) and 25 (18.25%) were positive
for antibodies of Mycoplasma capricolum subsp. capripneumoniae respectively using complement fixation test (CFT). The seroprevalence of CCPP in goats among the three districts was statistically
significant (x2 = 76.00, p < 0.001). In this study there was no statistical significant variation in the seroprevalence of CCPP in both sexes
(x2 = 3.619, p = 0.0571) and age (x2 = 0.990, p = 0.095) groups. The finding of high seroprevalence of CCPP in sheep (18.25%) could indicate that sheep are potential
carriers of Mccp. 相似文献
83.
Estrus synchronization in sheep with synthetic progestagens 总被引:1,自引:1,他引:0
Hayatu Awel Lisanework Eshetu Gebrehiwot Tadesse Alemselam Birhanu S. K. Khar 《Tropical animal health and production》2009,41(7):1521-1524
Sixteen female sheep of Degua breed were assigned to receive either the full dose of norgestomet ear implant and injectable
solution containing norgestomet and estradiol valerate (n = 8) or half the dose (n = 8). The ear implants were removed in
both groups on day 12. All ewes received an intramuscular administration of 500 IU PMSG at implant withdrawal. Synchronized
ewes were individually hand mated twice at 48 and 60 hours after implant removal. One ewe in each group however refused mating
on both occasions. Pregnancy diagnosis was conducted by bimanual external palpation 90 to 100 days post mating. The conception
rates (3/7, 42.85%) and (5/7, 71.42%) were recorded in the two treatment groups, respectively. All eight ewes lambed between
145 to 153 days post mating. In group I ewes carried only singletons (prolificity rate 1.0) whereas in group II two ewes delivered
twins, producing 7 lambs with prolificity rate of 1.4 (N.S). From this preliminary investigation it appears that the lower
dose of norgestomet ear implants offers better option for estrus synchronization accompanied by higher fertility. 相似文献
84.
Megersa B Biffa D Abunna F Regassa A Bohlin J Skjerve E 《Tropical animal health and production》2012,44(7):1643-1651
A highly acute and contagious camel disease, an epidemic wave of unknown etiology, referred to here as camel sudden death syndrome, has plagued camel population in countries in the Horn of Africa. To better understand its epidemic patterns and transmission dynamics, we used epidemiologic parameters and differential equation deterministic modeling (SEIR/D-model) to predict the outcome likelihood following an exposure of susceptible camel population. Our results showed 45.7, 17.6, and 38.6 % overall morbidity, mortality, and case fatality rates of the epidemic, respectively. Pregnant camels had the highest mortality and case fatality rates, followed by breeding males, and lactating females, implying serious socioeconomic consequences. Disease dynamics appeared to be linked to livestock trade route and animal movements. The epidemic exhibited a strong basic reproductive number (R (0)) with an average of 16 camels infected by one infectious case during the entire infectious period. The epidemic curve suggested that the critical moment of the disease development is approximately between 30 and 40?days, where both infected/exposed and infectious camels are at their highest numbers. The lag between infected/infectious curves indicates a time-shift of approximately 3-5?days from when a camel is infected and until it becomes infectious. According to this predictive model, of all animals exposed to the infection, 66.8 % (n?=?868) and 33.2 % (n?=?431) had recovered and died, respectively, at the end of epidemic period. Hence, if early measures are not taken, such an epidemic could cause a much more devastative effect, within short period of time than the anticipated proportion. 相似文献
85.
T. Bekele 《Veterinary research communications》2000,24(8):585-586
Veterinary Research Communications - 相似文献
86.
New Forests - In Laos, there are extensive shifting cultivation areas and regrowth forests spontaneously established on fallow lands. The aims of the study were to conduct a comparative study of... 相似文献
87.
Binyam Alemu Yosef Zewdu Eshetu Efrem Garedew Habtemariam Kassa 《Journal of Sustainable Forestry》2019,38(7):629-650
ABSTRACTThis paper examined the potential of dry north western woodlands of Ethiopia (Adi Goshu, Lemlem Terara, and Gemed) for carbon stocks. Allometry equations were used to determine the aboveground, belowground, and dead woods biomasses; litter and herbaceous biomasses were determined using direct harvesting method. The result showed the estimated mean carbon stocks of the aboveground, belowground, and the dead wood biomass for the Untapped Boswellia Papyrifera Woodland (UW) in Lemlem Terara site were significantly higher (P < 0.05) than that of the Adi Goshu site. In the Gemed site, the mean Herb Biomass Carbon (HBC) stock was 1.2 Mg ha?1, which is significantly highest (P < 0.05) than the other two study sites (Lemlem Terara, 0.42 Mg ha?1 and Adi Goshu, 0.45 Mg ha?1) for the Tapped Boswellia Papyrifera Woodland (TW). In UW, the mean soil carbon stock of the Lemlem Terara site (58.19 Mg ha?1) was significantly (P < 0.05) higher than that of Adi Goshu (33.61 Mg ha?1). In the case of the total carbon stocks in UW stratum, for the Adi Goshu site, the carbon stock was estimated to be about 55.26 Mg ha?1 while 96.74 Mg ha?1 for Lemlem Terara. Therefore, Carbon stock in different carbon pools (aboveground and belowground biomass, dead wood, litter, herbaceous biomass, and soil) has a potential to decrease the rate of enrichment of atmospheric concentration of carbon dioxide. 相似文献
88.
Survey of ixodid ticks in domestic ruminants in Bedelle district,Southwestern Ethiopia 总被引:1,自引:1,他引:0
Mesele Abera Tirazu Mohammed Rahmeto Abebe Kassaye Aragaw Jemere Bekele 《Tropical animal health and production》2010,42(8):1677-1683
A survey aimed at determining the status of ticks in cattle, sheep and goats in Bedelle district (Southwestern Ethiopia) was
carried out from November 2007 to April 2008. Out of the total 330 animals examined, 314 (95.2%) were found to be infested
(harbouring of at least a single tick). High rates of infestations were recorded across all three host species. Factors like
month of collection, age and sex of host species did not show significant association with infestation rates. A total of 5,507
ticks belonging to three genera (i.e. Amblyomma, Boophilus and Rhipicephalus) were collected during the study period of which six species were identified. The species of ticks encountered comprise of
Amblyomma cohaerens (44.1%), Amblyomma variegatum (13.8%), Amblyomma lepidum (1.2%), Boophilus decoloratus (24.9%), Rhipicephalus evertsi evertsi (14.3%) and Rhipicephalus lunulatus (1.7%). As about 86.7% (4,772) of the ticks were collected from cattle, it was recognised that this could be an evidence
of host preference where cattle are serving as principal host while sheep and goats serve as alternative hosts. The role of
ecological factors and little attention paid by livestock owners for treatment of animals against ticks are suggested to result
in the abundance of ticks. Acaricide spraying should be strategically applied to control ticks. Better result could be achieved
if an emphasis is being put on spraying cattle. Studies on tick-borne diseases, involvement of wildlife species as well as
related factors are recommended as they may provide a valuable basis for designing and launching an all-round control programme
in the country. 相似文献
89.
Multivariate methods, including principal component, cluster and discriminant analyses, were used to assess the patterns of morphological variation and to group 415 sorghum accessions for 15 quantitative characters. The first five principal components explained 79% of the total variation with plant height and days to 50% flowering being the most important characters in the first principal component. Cluster analysis grouped the accessions into ten clusters. A greater proportion of accessions of similar adaptation zones and accessions from regions of origin with similar agro-climatic conditions were grouped together. Moreover, discrimination of accessions was more pronounced when discriminant analysis was based on zone of adaptation rather than regions of origin. Based on the observed patterns of variation, it is concluded that the morphological variation in the material studied is structured by environmental factors. The implications of the results for plant breeding and germplasm conservation programmes arediscussed. 相似文献
90.