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21.
In the humid and subhumid tropics, trypanosomosis is an economically important zoonotic protozoan disease of the commonly kept farm animal species and their wild relatives. For example, more than 20% of the humid western and southwestern Ethiopia, which is home to more than 14 million heads of cattle, is under varying levels of trypanosomosis risk. Our study was, therefore, initiated to document farmers’ perception on trypanosomosis and Sheko’s trypanotolerance character. Our findings showed that trypanosomosis was the most frequently reported cattle disease in the Bench Maji Zone. Accordingly, 76.7% of the farmers reported the epidemiological importance of trypanosomosis, and they also noted that trypanosomosis on average accounted for 63.0% of annualized cattle death. The reported signs of trypanosomosis and trypanotolerance indicators were consistent with literature reports. Moreover, 66.7% of the farmers reported Sheko’s trypanotolerance character. In the course of time, smallholder farmers have developed ethnoveterinary practices that are mainly used to prevent the landing of vector flies on the animal. Wet and warm seasons of the year, i.e., spring and, to some extent, the beginning of summer and autumn, were reported as peak periods of trypanosomosis risk. Therefore, this showed the need for incorporating farmers’ knowledge in trypanosomosis control programs.  相似文献   
22.
Rearing of scavenging chickens is among the most commonly practiced farm activities in Ethiopia. This system is dominated by indigenous chickens. Output from indigenous chickens is low due to poor management and absence of intense selection that is intended to improve economically important traits. This showed that village chickens are rather evolved for adaptation traits. However, the level of risk is low, and this has made rearing of scavenging chickens a choice of farm activity for smallholder farmers. The objective of this study was to characterize the scavenging chickens’ production system in Wolaita Zone. Single-visit survey involving individual interview of 119 farmers and 6 focus group discussions was used to collect the data. Our results showed that rearing of scavenging chickens was constrained especially by disease and predation problems. However, farmers proposed a set of solutions to minimize the effect of these problems. Rearing of scavenging chickens fulfils the multi-functional need of the society. This system has special features because it can sustain in its own without the need for modern commercial chicken farming facilities. However, farmers also reported the drawbacks of rearing of scavenging chickens and these mainly include uproot of garden crops and tiresomeness of the night watching. Selection of chickens was mainly depending on physically observed traits like body size and plumage colour. The initial foundation flock was mainly obtained from the local market. The ideal place for scavenging chickens production is the one that has intermediate weather condition and has some trees that can be used as shade; however, it was substantiated that it has to be free from bush and shrubs, weeds and wet lands. Therefore, these pieces of knowledge embedded among smallholder farmers need to be well documented and synthesized to design an appropriate type of technology packages that can be communicated back to farmers to improve productivity of the scavenging chickens.  相似文献   
23.
The aim of the study was to determine the prevalence of infectious keratoconjunctivitis on cross-breed dairy farms and to evaluate factors that influence its distribution. A total of 11 dairy farms and one cattle cross-breeding farm in different parts of Arsi region, south-east Ethiopia were clinically and bacteriologically investigated from February 1989 to December 1990. Out of 5221 local zebu and cross-breed dairy animals, 110 were found to have different degrees of infectious bovine keratoconjunctivitis. Of these, 94 (85.5%) were unilateral and 16 (14.5%) were bilateral. The prevalence of the disease was significantly (P < 0.001) influenced by age and breed; high exotic blood level and younger age groups were mainly affected. However, severity of the disease was not significantly associated with age (P > 0.750). Moraxella bovis was isolated from 88 (80%) of the 110 bacteriologically positive cases. Of these isolates, 61 (69%) were haemolytic and 27 (31%) were non-haemolytic strains. Infection with M. bovis was unilateral. Concurrent infections with M. bovis included Actinomyces pyogenes 23 (21%), Staphylococcus aureus 17 (15%), Pasteurella haemolytica nine (8%), Escherichia coli eight (7%) and Proteus spp. four (3.6%).  相似文献   
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为给抗叶锈病育种提供优异抗源,选用17个不同毒力的叶锈菌生理小种,对69份国外小麦品种(系)及36份已知抗病基因的近等基因系进行苗期抗叶锈病基因推导,并结合11个已知基因的分子标记进行标记检测;于2017-2018年度分别在河北保定试验田和河南周口黄泛区农场对69份国外小麦材料进行田间成株期抗叶锈性鉴定。结果发现,在69份国外小麦品种(系)中共检测到6个抗小麦叶锈病基因 (Lr1Lr10Lr19Lr26Lr34Lr37),携带苗期抗病基因Lr1Lr10Lr19Lr26的分别有6、19、5和10份品种(系),携带成株抗病基因Lr34Lr37的分别有10和26份品种(系),田间鉴定具有成株慢锈性的品种(系)共有46份。  相似文献   
26.
The sow at parturition is challenged with respect to energy status due to increases in energetic expenses associated with 1) nest building 2) uterine contractions, and 3) colostrum production. A previous study indicated that sows were depleted of glucogenic energy around farrowing. The aim was to investigate whether intravenous infusion of glucose from observed nest-building behavior to 24 h postpartum affected the farrowing kinetics and colostrum production in sows. Ten multiparous sows (DanBred landrace × DanBred Yorkshire) were fitted with a jugular vein catheter on each side (one for infusion and the other one for blood sampling). Sows were infused with either 0.9% saline (CON; n = 5) or 10% glucose (GLU; n = 5) solution at a constant rate of 125 mL/h. From day 108 of gestation, sows were fed once daily with 3.33 kg of a standard lactation diet. During farrowing, sows were monitored to register the onset of farrowing, time of birth, birth status (live or dead), sex, stillbirth rate (SR), and weight of newborn piglets. Farrowing assistance (FA) was provided when the birth interval exceeded 60 min. In late gestation, 1 mL of blood was collected every third hour for blood gas analysis and every sixth hour for harvesting plasma. During farrowing, 1 mL (for blood gas) and 9 mL of blood were collected at 0, 3, 6, 9, 12, 15, 18, 21, and 24 h in milk (HIM). Colostrum and milk samples were collected at 0, 6, 12, 18, 24, and 36 HIM and also at 3, 10, 17, and 24 d in milk. Compared with CON sows, GLU infusion decreased the SR (16.1% vs. 7.4%; P = 0.03), FA (21% vs. 9.0%; P = 0.01), and surprisingly also blood glucose at the onset of farrowing (5.53 vs. 5.09 mmol/L; P = 0.03), respectively. A tendency to higher plasma lactate at the onset of farrowing (P = 0.05) but decreased piglet survival from 0 to 24 h (P = 0.06) was also found for GLU sows. No effects of treatment on farrowing duration or mean birth intervals were found. Lactate in whole blood (P = 0.003) and plasma (P = 0.002) was increased for GLU sows as compared with CON sows during the colostrum period. No effect of GLU infusion was seen on colostrum and milk composition and yield. The increase in lactate was most likely due to a shift toward a greater proportion of glucose oxidation and insufficient O2 supply to fuel uterine contractions. In conclusion, infusion of glucose reduced the frequency of SR and FA, and improved energy status of the sow which seems to be crucial to enhance total piglet survival.  相似文献   
27.
An increase in energy demand leads to further exploration, transportation, and utilization of petroleum, which creates severe soil contamination because of recurrent accidents and oil spills. Remediation of these contaminated soils is challenging. Among many treatment methods practiced for remediation of petroleum-contaminated soils, surfactant-enhanced soil washing has been widely practiced as a preferred treatment option, as it is a fast and environmentally accepted method. In this paper, we review research undertaken on various anionic, nonionic, cationic, biological, and mixed surfactants for the remediation of petroleum hydrocarbon-contaminated soils. Upcoming surfactants like gemini and switchable surfactants are summarized. We assess the challenges and opportunities of in-situ and ex-situ soil washing, the mechanisms of surfactant-enhanced soil washing, and the criteria to follow for surfactant selection. Furthermore, we briefly discuss the operational and environmental factors affecting soil washing efficiency and soil and surfactant properties affecting surfactant adsorption. We also describe the advantages of coupling soil washing with effluent treatment and surfactant reuse challenges and opportunities. Moreover, challenges and possible new directions for future research on surfactant-enhanced soil washing are proposed.  相似文献   
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This study describes a novel multilocus variable number tandem repeat analysis (MLVA) based on six variable number of tandem repeat (VNTR) loci for genotyping of 37 Edwardsiella piscicida (previously Edwardsiella tarda) isolates from multiple sources. The number of alleles identified for each of the six VNTR loci ranged from 3 to 5 with VNTR loci 1 (DI = 0.632) and 3 (DI = 0.644), displaying the highest degrees of polymorphism. MLVA typing of the 37 E. piscicida isolates resulted in the identification of five major clusters consistent with their geographical origins, and were designated as MLVA types I, II, III, IV and V. Types III and V were resolved further into subtypes largely consistent with outbreak source. An MLVA profile comprising a string of integers representing the number of tandem repeats for each allele provided a unique identification for each MLVA type and/or strain. The MLVA protocol described in the current study is robust, relatively simple, has a higher power of resolution than multilocus sequence analysis (MLSA) and is capable of discriminating closely related isolates.  相似文献   
30.
Cordia africana is a very important indigenous tree species for timber and other products and services in Ethiopia. Seed traits and seedling vigour of seeds from 12 provenances of the species were compared. Mean seed mass for each provenance was assessed for 1000 seeds in 10 replications, and seed length and width were measured for 100 seeds in four replications per provenance. Germination was assessed in a glasshouse taking 400 seeds from each provenance. Root collar diameter and height of 440 seedlings grown in a nursery for 290 days in Addis Ababa were measured. Seed length, seed width, seed mass, and shoot height and root collar diameter of seedlings showed significant differences (P < 0.001) among provenances. Correlation analysis between seed and seedling traits and environmental variables revealed significant positive correlations between seed width and germination percentage, seed width and altitude, seed width and longitude and seed length and latitude. Negative correlations were obtained between seed width and temperature, seed width and rainfall, seed mass and temperature, and germination and temperature of the seed source. As expected, differences in seed trait did not explain the variability in seedling vigour. Determining quantitative variations in seed traits and seedling vigour among provenances and the patterns along environmental gradients are essential for informing decisions on the tree improvement programme of the species.  相似文献   
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