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31.
OBJECTIVES: To summarize the presenting complaints and clinical signs associated with traumatic penetrating injuries to the canine oropharynx. To determine how the site of injury, causative agent, and duration of disease affect the presentation and clinical outcome of treatment. STUDY DESIGN: Retrospective study. SAMPLE POPULATION: 50 client-owned dogs. METHODS: The medical records of 50 dogs with oropharyngeal penetrating injuries referred to Glasgow University Veterinary Hospital (GUVH) between 1979-1999 were reviewed. Data regarding signalment, owners' presenting complaint, history, physical examination, radiographic and endoscopic findings, surgical findings, and outcome were recorded and compared with the GUVH population. Estimates of individual breed-specific odds ratios were calculated. Outcome was evaluated by reexamination 6 weeks after surgery with recurrence of disease recorded as failure. RESULTS: Oropharyngeal injuries occurred most often in medium to large breed dogs. The majority of dogs presented with chronic disease (82%). The common findings on clinical examination were discharging sinus (72%) and swelling (70%). Acute cases typically presented with dysphagia and oral pain. The original site of injury was evident in only 34% of dogs, with the sublingual area the most frequently traumatized. The apparent cause of injury to the oropharynx was most commonly a piece of wood (72%). Other causes were metallic foreign bodies (3 dogs) and bones (2 dogs). In the remaining 9 dogs, the cause was not determined. The clinical signs resolved in all dogs that presented acutely compared with only 62% in dogs with chronic signs. CONCLUSION: Medium to large breed dogs appear to be prone to oropharyngeal injuries caused mainly by wooden foreign bodies. This may be attributable to stick chewing or retrieving behavior in these animals. CLINICAL RELEVANCE: History of trauma, stick retrieval, submandibular/cervical swelling, and discharging sinus are commonly encountered in the presentation of this condition. The sublingual area was the most frequent portal of entry recorded, although in chronic cases the initial site of injury was often unclear. Radiography and endoscopy, while offering definitive diagnosis with positive findings, often provide false negative findings. Aggressive surgical debridement of all sinus tracts is essential in obtaining a successful result, but recovery of a foreign body is not necessarily a determinant of success. 相似文献
32.
Abraham Hagos Gizaw Solomon Urge Mengistu 《Tropical animal health and production》2018,50(8):1887-1892
Tropical Animal Health and Production - A sound breeding objective is the basis for genetic improvement in overall economic merit of farm animals. Begait goat is one of the identified breeds in... 相似文献
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A conceptual model was tested for explaining environmental and physiological effects on leaf gas exchange in the deciduous dry tropical woodland tree Boswellia papyrifera (Del.) Hochst. For this species we aimed at (i) understanding diurnal patterns in leaf gas exchange, (ii) exploring cause-effect relationships among external environment, internal physiology and leaf gas exchange, and (iii) exploring site differences in leaf gas exchange in response to environmental variables. Diurnal courses in gas exchange, underlying physiological traits and environmental variables were measured for 90 trees on consecutive days at two contrasting areas, one at high and the other at low altitude. Assimilation was highest in the morning and slightly decreased during the day. In contrast, transpiration increased from early morning to midday, mainly in response to an increasing vapor pressure deficit (VPD) and gradual stomatal closure. The leaf water potential varied relatively little and did not influence gas exchange during the measurement period. Our results suggest that the same cause-effect relationships function at contrasting areas. However, leaves at the higher altitude had higher photosynthetic capacity, reflecting acclimation to higher light levels. Trees at both areas nevertheless achieved similar leaf assimilation rates since assimilation was down-regulated by stomatal closure due to the higher VPD at the higher altitude, while it became more light limited at the lower altitude. Gas exchange was thus limited by a high VPD or low light levels during the wet season, despite the ability of the species to acclimate to different conditions. 相似文献
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Gebretnsae Mezgebe Solomon Gizaw Mengistu Urge 《Tropical animal health and production》2018,50(6):1313-1318
The performance of indigenous Begait cattle (498 cows, 284 calves, and 48 heifers) in northern Ethiopia was studied. System of herd management significantly (P?<?0.01) influenced all production traits. Calves in medium-input herds (MIHM) grew faster than those in low-input herds (LIHM), by 232 g/d from birth to 9 months (Gain1) and by 385 g/d from 9 to 12 months (Gain2). Cow’s dry period, calving interval (CI), and age at first calving (AFC) were 234, 222, and 343 days shorter for MIHM than for LIHM. Compared with LIHM, cows from MIHM had 74% higher daily milk yield (DMY) and 91% higher lactation milk yield (LMY). Calves born at wet season grew faster by 14 and 10% than those calves born in the dry season at Gain1 and Gain2. The subsequent CI of cows calved in the wet season had 77 days shorter, 0.45 kg DMY, and 93 kg LMY increment. The differences between production systems can be attributed to differences in management skills and access to better quality feeds. Technical intervention is needed to ensure provision of balanced rations to exploit the potential productivity of Begait cattle. 相似文献
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In Ethiopia, lack of quality forage in adequate quantities is a major constraint to livestock productivity. Fast growing N2 fixing Sesbania have shown great promise both as high quality fodder and green manure. The objective of this study was to evaluate and select
among the species S. macrantha, S. rostrata, S quadrata and S. sesban for fodder yield, quality and green manure potential. The field experiment was conducted on a light soil (loam, Alfisol) and a heavy soil (cracking type clay, Vertisol) at Debre Zeit (9° N and 39° E, 45 kms SE of Addis Ababa). There were two cutting treatments: cutting once at ground level
or cutting twice at 50 cm (first, 65 days after sowing; second, 40 days later). A two-factor factorial in randomized block
design was used. S. macrantha performed better on the light soil producing the highest dry matter (DM) yields of leaf (2.8 t/ha), stem (6.3 t/ha) and total
nitrogen (151 kg/ha) in 105 days than the rest of the species. Most species performed poorly on the heavy soil. S. quadrata, however, showed better adaptability to the heavy soil (5.5 t/ha DM) than any of the other species. The lowest DM yield was
recorded for S. rostrat which could be due to poor nodulation. Cutting twice over the 105 days growth period caused a drastic reduction in DM yield,
but resulted in higher leaf-to-stem ratio and total N yield. The nutritional composition of all the species was within an
acceptable range for livestock requirements. N content (4%) and IVDMD (over 70%) were high. S. macrantha had superior overall performance and seems promising both as high quality fodder and green manure crop. Under rain-fed conditions,
cutting once was better than cutting twice particularly for S. macrantha.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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Improved water management through precise crop water requirement determination is needed to improve the efficiency of water
use in agricultural production. As a result, appropriate irrigation scheduling which can lead to water saving, improvements
in the yield and income can be designed. In this study, three non-weighing lysimeters having dimensions of 2 m × 1 m × 2 m
were used to determine water requirement (ETc) and crop coefficient (Kc) of onion (Bombay Red cultivar). Reference crop evapotranspiration (ETo) was determined using weather data recorded at the site. The measured ETc values were 51.3 mm, 140.5 mm, 144.8 mm, and 53.9 mm during the initial, development, mid-season and late season growth stages
respectively. Crop coefficient (Kc) values, calculated as ratio of ETc to ETo, were 0.47, 0.99, and 0.46 during the initial and mid-season stages and end of late season. Furthermore, third-order polynomials
were fitted well to predict the crop coefficient values as functions of growing degree-days (GDD). 相似文献
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Kebede Gezahagn Feyissa Fekede Assefa Getnet Alemayehu Mengistu Mengistu Alemayehu 《Journal of Crop Science and Biotechnology》2020,23(3):215-228
Journal of Crop Science and Biotechnology - Vetch is an annual forage legume and accessions of its species performed differently under different soil conditions. Twenty accessions of five vetch... 相似文献
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Lemma W Mengistu George W Mueller‐Warrant Aaron Liston Reed E Barker 《Pest management science》2000,56(3):209-217
The herbicide‐binding region of the chloroplast psbA gene from a total of 20 biotypes of Poa annua L resistant and susceptible to metribuzin and diuron was selectively amplified using PCR. Sequence analysis of the fragment from six herbicide‐resistant biotypes of P annua exhibited a substitution from valine to isoleucine at position 219 of the D1 protein encoded by the psbA gene. This is the same mutation as reported for Chlamydomonas and Synechococcus through site‐directed mutagenesis and in cell cultures of Chenopodium rubrum L. To our knowledge this is the first report of a higher plant exhibiting resistance in the field to photosystem II inhibitors due to a psbA mutation other than at position 264. The existence of additional biotypes of P annua resistant to diuron or metribuzin but lacking mutation in the herbicide‐binding region indicates that resistance to these herbicides can also be attained by other mechanisms. © 2000 Society of Chemical Industry 相似文献
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Solomon Assefa Derese Hussein Shimelis Mark Laing Fentahum Mengistu 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2018,68(5):424-436
Purpose: Sorghum [Sorghum bicolor (L.) Moench] has been cultivated for centuries as a staple food crop for millions of people in sub-Saharan Africa and Asia. In Ethiopia a total of 4.34 million tons of sorghum is being produced per annum, predominantly in the arid and semi-arid areas. However, the yield and quality of sorghum is affected by a wide array of production constraints, notably severe and recurrent drought stress. The aim of this study were to determine the impact of drought on sorghum production and productivity over time and space, and to identify farmers’ trait preferences, production constraints and coping strategies when dealing with drought in north eastern Ethiopia.Materials and methods: Participatory rural appraisal (PRA) was employed in three administrative zones of north eastern Ethiopia. One Woreda from each Zone and two Kebeles from each Woreda were selected on the basis of sorghum area coverage, production, consumption and prior information on the intensity, duration and spatial coverage of drought. In each kebele, 30 respondents were selected for interview and 12 key informants were selected for group discussions and transect walk personal observations. Data collected from 180 respondents was subjected to statistical analysis and the information gathered from 72 key informants through focus group discussions and transect walk observations were used in discussing the results.Results and discussion: The present study found that productivity of sorghum was challenged by recurrent droughts, Striga infestation, insects, birds, diseases, a lack of varieties with farmers-preferred traits and high yield potential, limited policy support, a lack of improved seed system, poor sorghum production practices and application of crop input and poor soil fertility, in a decreasing order of importance. Among the listed sorghum production constraints, severe drought in the post-flowering stage was identified by most interviewed farmers as the leading constraint across the three study zones. Focus group discussions and transect walk observations held in each Kebele revealed that farmers’ had lost numerous valuable local landrace varieties due to extreme drought conditions over the years. A significant number of interviewed farmers preferred to grow high grain and biomass yielder medium-maturing sorghum varieties which can be sown at the normal planting time but which would escape post-flowering drought.Conclusion: Overall, sorghum breeding programme should be directed at developing farmers’ ideal sorghum varieties with high grain and biomass yield, adequate level of drought and Striga tolerance. In addition, development of farmer preferred medium-maturing sorghum varieties suitable for April planting should be strengthen to boost its productivity and to increase varietal adoption rate in the area. 相似文献