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51.
Bekele T 《Tropical animal health and production》1999,31(6):333-345
New epidemics of respiratory disease have caused 29.6 morbidity and 6.4% mortality in camels in the Somalia region of Ethiopia. The major clinical signs observed were fever of 40–41.5°C, depression, cough, loss of appetite and a watery nasal discharge that became mucopurulent at a later stage. Finally, the camel became recumbent and extended its neck straight along the ground. Some of the animals died within 8–9 days. The major post-mortem lesions were hydrothorax, adhesion of the lung to the thorax, red and grey hepatization, emphysema, hydropericardium and fibrinous pericarditis. A treatment trial indicated that oxytetracycline was more effective than a combination of penicillin and streptomycin, the results showing a significant difference (p>0.05) between the treated and control groups. The bacteria isolated from lung, thoracic fluid and whole blood were Pasteurella haemolytica. Further studies on the epidemiology of this disease, the identification of the serotypes involved, and the demonstration of any primary viral initiating agent are recommended to allow the development of preventive methods. 相似文献
52.
U Besenfelder V Havlicek G Moesslacher M Gilles D Tesfaye J Griese M Hoelker P Maddox Hyttel J Laurincik G Brem K Schellander 《Reproduction in domestic animals》2008,43(5):566-572
The collection of extra numbers of bovine embryos by superstimulation of donors underlies variation concerning yield of morulae and blastocysts. Our study aimed at establishing a correlation between hormonal treatment and embryo development during oviductal passage including repeated flushing. A transvaginal endoscopic procedure was used to flush the oviducts at six different time intervals (beginning at 24 h until 105 h) after artificial insemination. In total, 119 animals were superovulated using either FSH or eCG. The hormonal treatment resulted in the stimulation of 2076 follicles of which 77% (1590 CL) ovulated. The bilateral flushing resulted in the collection of 1411 complexes (collection rate: 89%), of which 78% (1098) were assessed as viable embryos. The use of FSH resulted in significantly more stimulated follicles and ovulation sites compared with eCG (p < 0.001). Generally, the embryo kinetics were similar among the FSH and eCG treated animals. However, the embryo cleavage of the eCG treated animals was ahead of that of the FSH group comparing the different collection time points. The overall proportions of non‐viable embryos in both groups were similar. Regarding the embryo collection intervals in the eCG group, this proportion significantly increased during 51–105 h compared to 24–50 h (p < 0.05), whereas FSH delivered constant results. It was shown that the repeated endoscopic collection of oviductal stage embryos had no negative influence on the collection parameters. It is concluded that the introduced transvaginal endoscopic technique could have main impact on further studies focusing on early embryo development. 相似文献
53.
Bekele ST 《Tropical animal health and production》2008,40(1):25-28
Camels are important animals for pastoralists in the northeastern, eastern, southeastern and southern parts of Ethiopia. This
paper reports on abattoir study of respiratory lesions in 104 adult camels at the Dire Dawa abattoir (88 male and 16 female).
The study showed 98% of the examined lungs had one or more lesions. The most common lesions were pulmonary fibrosis (50.00%),
pneumoconiosis (34.62%), hydatid cyst (30.80%), pulmonary abscess (3.85%) and parasitic bronchopneumonia (0.96%). The distribution
of pneumoconiosis and hydatid cyst varied significantly (p < 0.05) among different lobes, the highest being seen in the caudal
lobe. For the different lesions there was no significant (p > 0.05) difference in distribution among male and female camels.
Possible explanations for the occurrence of the lesions are discussed. And recommendations forecasted are made. 相似文献
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55.
Influence of variety and nitrogen fertilizer on productivity and trait association of malting barley
Poor soil fertility is a major constraint to crop productivity in the highlands of Ethiopia. This study was conducted to evaluate the effects of nitrogen (N) fertilization, variety and growing season on grain yield and yield related traits, and determine relationships among agronomic traits of malting barley. The treatments studied were five N levels (0, 23, 46, 69 and 92?kg ha?1) and two malting barley varieties (Miscal-21 and Holker) over three growing seasons (2012, 2013 and 2014) at Bekoji, south eastern Ethiopia. The results revealed that as N rates increased, grain yield, number of tillers and spikes per square meter, biomass yield at harvest, days to physiological maturity, spike length and number of kernels per spike increased, but harvest index decreased. Grain yield, harvest index, number of tillers and spikes per square meter, spike length and biomass yield at harvest were greater in Miscal-21, whilst days to maturity and number of kernels per spike were greater in Holker. Grain yield, harvest index, number of tillers and spikes per square meter, spike length, biomass yield at harvest and days to maturity were significantly affected by seasonal conditions, but spike length and kernels per spike were not affected. Grain yield was positively influenced by the number of tillers per square meter, biomass yield at harvest, spikes per square meter, spike length, kernels per spike and harvest index. However, the number of tillers per square meter followed by biomass yield and spikes per square meter largely determined grain yield. The results of the current study suggest that genetic improvement of those yield related traits is the likely basis of increasing grain yield in barley. 相似文献
56.
Phosphorus uptake by plant roots and arbuscular mycorrhizae (AM) hyphae can be described based on morphological and physiological uptake characteristics and parameters affecting P transport in the soil to the uptake surface. The current study aimed to quantify the relative contribution of hyphae and roots to P uptake of onion and to investigate the associated mechanisms using a mechanistic simulation model. Onion was grown in a growth chamber under controlled conditions at five levels of P supply with (M) or without (NM) AM. Uptake by onion roots and AM hyphae was simulated separately using a nutrient‐uptake model, which was developed for roots. Model parameters describing P transport in the soil, as well as morphological and physiological uptake characteristics of roots and hyphae were derived from soil and nutrient‐solution experiments. The model fairly described P uptake of M and NM plants at the highest level of P supply (28 µM P in soil solution) where roots and hyphae contributed nearly equally to P uptake of M plants. However, at lower P levels (≤0.41 µM P), hyphae accounted for nearly the whole P uptake whereas roots hardly explained any uptake. The effectiveness of AM hyphae at low P supply was well explained by their favorable morphological and physiological uptake properties. Hyphae were characterized by a diameter of 3 × 10–4 cm, a Km of 0.25 µM, and a Cmin of 0.04 µM, values that are about 200, 40, and 10 times lower, respectively, compared to those of roots. Not more than 60% of the uptake at lower levels of P supply could be explained by the sum of predicted uptake of roots and hyphae suggesting that hyphae and roots may have used mechanisms additional to those described by the model to mobilize P. This work demonstrated that mechanistic models can be useful tools to study the role of AM in P uptake of plants, although reliable estimation of model parameters, especially physiological uptake properties of AM, is still limiting this approach. 相似文献
57.
Occurrence of mastitis and associated risk factors in lactating goats under pastoral management in Borana,Southern Ethiopia 总被引:1,自引:1,他引:0
Bekele Megersa Chala Tadesse Fufa Abunna Alemayehu Regassa Berhanu Mekibib Etana Debela 《Tropical animal health and production》2010,42(6):1249-1255
Mastitis prevalence and related risk factors were studied in 1,072 udder halves of 536 lactating goats from October, 2008
to February, 2009. Clinical and subclinical mastitis were prevalent in 4.3% (95% CI = 2.8, 6.5) and 11.2% (95% CI = 8.7, 14.3)
of the studied animals, respectively, resulting in an overall prevalence of 15.5% (95% CI = 12.6, 18.9). Univariate analysis
of the potential risk factors has depicted that mastitis was more prevalent in does with previous mastitis history, increased
parity, poor body conditions, increased milk production, late lactation stage, long teat, and housed goats. Furthermore, prevalence
was significantly higher (p < 0.05) during the wet period of October to November than the dry periods of January to February. No significant variations
(p > 0.05) were observed in mastitis prevalence with udder tick infestation, mixing goat with sheep and flock size. With multivariable
analysis, lactation stage, teat length, body condition, and season (wet months) have showed significant association with mastitis
prevalence, and these factors maintained significant in the stepwise elimination of multivariable logistic regression model.
As a result, does in late stage of lactation (OR = 4.3, 1.8, 10.4), poor body condition (OR = 5.0, 1.7, 10.0), long teats
(OR = 2.2, 95% CI = 1.1, 4.2) and does examined in wet period were at higher risk of udder infections than early lactation,
good body condition, short teat, and examined in dry period, respectively. The study showed occurrence of mastitis and associated
risk factors in studied goats, which suggests the need for control intervention. Further investigations into pathogens involved
in goat mastitis will optimize our knowledge of causative agents and control interventions. 相似文献
58.
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60.
Morales ML Tesfaye W García-Parrilla MC Casas JA Troncoso AM 《Journal of agricultural and food chemistry》2002,50(11):3173-3178
Changes in the aroma profile of five Sherry wine vinegars submitted to an experimental static aging in wood were followed along 24 months. Eighteen volatile compounds were determined by GC-FID. The results were subjected to multivariate analyses: principal component analysis and linear discriminant analysis. The aroma profile of vinegar can be useful to discriminate vinegars produced from different substrates or with different aging times. During the experimental aging, volatile compounds such as methyl acetate, methanol, diacetyl, and gamma-butyrolactone underwent significant concentration increases. Moreover, the initial ethanol content of vinegars is a factor in the final aromatic richness. The formation of ethyl acetate stood out in samples with an initial ethanol content of approximately 2 alcoholic degrees. 相似文献