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91.
92.
A survey was conducted in central Ethiopia to elicit information on existing and potential dissemination pathways for technical information on donkey husbandry. A detailed socio-economic survey was also conducted to provide background information on the people and the region, and livelihood indicators were drawn out at the same time. The results showed that there are many opportunities for group dissemination by making use of existing social networks. There are also opportunities for dissemination through extension agents, farmer groups and radio broadcasting.  相似文献   
93.
The objective of the study was to estimate the prevalence and losses associated with subclinical mastitis (SCM) caused by Staphylococcus aureus in Ethiopian crossbred dairy cows. A split-udder trial was carried out to determine milk yield losses in udder quarter with S. aureus-caused SCM. Each quarter of the study cows was examined using the California Mastitis Test (CMT) and quarter milk production was measured over a period of 8 days. Milk yield losses for CMT positive quarters were estimated by comparing production of quarters with CMT score 0. Mean milk yield for uninfected healthy quarters was 1.66 kg per milking (95% CI, 1.66–1.55 kg per milking), and the rate of milk reduction for quarters with CMT scores of 1+, 2+, and 3+ was 25%, 33%, and 48%, respectively. Economic losses at different farm-size levels were calculated by multiplying the prevalence of CMT scores with milk yield losses associated with respective CMT scores. In Debre Ziet dairy herds, a quarter with SCM due to S. aureus lost an average of 34.5% of its potential milk production while the total milk yield loss per cow was estimated at 6.8%. Losses were highest in large-scale (13%) farms and lowest (3.7%) in small-scale. Based on the prevalence, the overall financial loss for each cow per lactation was 984.64 Eth Birr (US78.65) and losses in large farms (1,882.40 Eth Birr or US78.65) and losses in large farms (1,882.40 Eth Birr or US150.35) were over 3.5 times the loss in small-size farms. These figures possibly underestimate the potential benefits of mastitis control program as they do not include other direct and indirect costs.  相似文献   
94.
Groundnut is a major cash crop for smallholder farmers in several districts of eastern Ethiopia with low yield. Little or no fertilizer was applied for the crop possibly because no generic or recommended fertilizer and technology were available. Therefore, field experiments were conducted for 2 consecutive cropping seasons in Babile District, to investigate effects of applying mineral N and P fertilizer and vermicompost (VC) on seed yield and oil content of groundnut using an improved variety ‘BaHa-Gudo’. Treatments consisted of nitrogen (0,23 and 46 kg N/ha), phosphorus (0,46 and 92 kg P2O5/ha) and VC (0,2.5 and 5 t VC/ha). Results revealed that yield attributes, seed yield and seed oil content were significantly (p < 0.01) affected by fertilizers. Seed yield after combined application of 46 kg N, 46 kg P2O5 and 2.5 t VC/ha increased by about 113% compared to seed yield without any fertilizers. Enhancement in seed oil content at the aforementioned rate was 7.0%. It could, thus, be concluded that applying the aforementioned fertilizers would enable farmers to increase seed yield and oil content of groundnut for enhancing their income and livelihoods in the study area.  相似文献   
95.
A study was conducted to investigate causes of lamb morbidity and mortality on farms and on-station at Debre Berhan during 1989 and 1990. It showed pneumonia (bacterial and/or verminous), starvation-mismothering exposure (SME) complex, gastrointestinal parasites, enteritis, abomasal impaction and physical injuries to be important health constraints on productivity. Neonatal mortalities were 51.5% and 46.3% on farms and on-station respectively and occurred owing to management problems such as SME, abomasal impaction and physical injuries. On the farms the lamb birth weight was 2.56±0.25 kg and was significantly (p<0.05) affected by the dam's age, lambing weight, litter size, sex of lamb and year of lambing, but not by the season of lambing. Birth weight significantly (p<0.05) influenced lamb mortality. Lambs with a low birth weight tended to die from SME. Morbidities and mortalities due to infectious causes increased in older lambs, suggesting that infections were acquired with age when resistance was lowered owing to inadequate nutrition and poor management.Heavy loss of lambs could be overcome by such health management interventions as foster mothering, warming lambs during the cold season and vaccination with polyvalent vaccines against pasteurellosis, clostridial infection andDictyocaulus filaria.  相似文献   
96.
A cross‐sectional study was conducted from November 2017 to March 2018 at Lake Hawassa to determine the prevalence of larval Contracaecum infestation in Nile tilapia, (Oreochromis niloticus), African Catfish (Clarias gariepinus) and Barbus species (Barbus intermedius). Fifty‐two point six per cent (52.6%) previous prevalence and 5% precision were used to estimate the sample size. Accordingly, a total of 383 randomly sampled fish species comprising of 163 (42.6%) C. gariepinus, 159 (41.5%) O. niloticus and 61(15.9%) B. intermedius were examined. The length and weight of each sampled fish were recorded. All the sampled fish were examined for the evidence of Contracaecum parasites in Hawassa University Veterinary Parasitology and Pathology Laboratory. Chi‐square values and comparison of proportions were used to analyse the data. The overall prevalence of Contracaecum parasites of fish population was 31.6%. The distribution of parasite was significantly affected by fish species (p = .000), sexes (p = .018), length (p = .003) and weight classes of fish (p = .026). As a hygienic problem and gutting activity conducted at the sides of the Lake Hawassa and distribution of discarded fish wastes for surrounding piscivorous birds by butchers and other people, the life cycle of Contracaecum parasite was perpetuated. Thus, the parasite is of zoonotic significance. Therefore, awareness creation activities for societies and control of fish parasites should be conducted in the study area.  相似文献   
97.
The study was conducted to evaluate reproductive performances and estimate genetic parameters for reproduction traits in Arsi-Bale goats. A total of 792 kidding records collected from 2001 to 2007 were used. Parity of dam, year, season and type of kidding were investigated as fixed effects by PROC GLM of SAS. Derivative-Free Restricted Maximum Likelihood (DFREML) method was used to estimate genetic parameters by fitting four animal models. Parity of dam and year of kidding influenced (P < 0.05) all the traits. The overall means for age at first kidding (AFK), kidding interval (KI), litter size at birth (LSB), litter size at weaning (LSW), litter weight at birth (LWB), litter weight at weaning (LWW), abortion and dystocia were 574.9 ± 8.3 days, 280.0 ± 13.7 days, 1.6 ± 0.03, 1.37 ± 0.03, 3.7 ± 0.08 kg, 9.11 ± 0.38 kg, 3.8% and 0.13%, respectively. The estimates of direct additive heritability for the traits, except for abortion and dystocia, under the best model (direct animal for AFK and repeatability model for other traits) were 0.245 ± 0.19, 0.060 ± 0.08, 0.074 ± 0.05, 0.006 ± 0.05, 0.125 ± 0.05, 0.053 ± 0.07, respectively, while the corresponding permanent environmental effects were 0.00 ± 0.00, 0.07 ± 0.07, 0.08 ± 0.05, 0.172 ± 0.06, 0.03 ± 0.04 and 0.07 ± 0.05, respectively. Repeatability estimates for KI, LSB, LSW, LWB and LWW were 0.13, 0.15, 0.18, 0.16 and 0.12, respectively. Genetic correlations between reproductive traits vary from medium to high. Arsi-Bale goats have good reproductive performance with low incidence of reproductive disorder. Except for AFK, other traits have low estimates of heritabilities with high genetic correlation among the traits. Repeated measures of the traits are needed before deciding to keep or cull the animal.  相似文献   
98.
Olive flounder is the most important species for the Northeast Asian fish farming industry. However, this species is substantially affected by multiple infectious agents, including Streptococcus parauberis. Evaluation of antibiotics before their application is critical to treat infections and prevent drug resistance. Therefore, in this study, the pharmacodynamics of amoxicillin (AMX) and other antimicrobials against the planktonic‐ and biofilm‐forming bacteria were assessed. The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and Time–kill curve assay were analysed using micro‐dilution method. The minimum biofilm eradicating concentration (MBEC) was determined using the Calgary Biofilm device. The effects of temperature, pH, hardness and salinity were detected for both planktonic‐ and biofilm‐forming bacteria. The MIC of AMX ranged from 0.015 to 2 μg/ml, whereas that of cephalexin (CEP), enrofloxacin (ENR) and oxytetracycline (OTC) ranged from 0.125 to 256, 0.125 to >512 and 0.25 to >512 μg/ml respectively. No bacteria were resistant against AMX, while the percentage of resistance to CEP, OTC and ENR were 68.7%, 52.6% and 11.1% respectively. The IC50 of AMX, CEP, ENR and OTC was 0.03, 0.091, 0.015 and 0.213 μg/ml respectively. The MBEC of amoxicillin against S. parauberis ranged from 0.5 to 16 μg/ml. Higher rates of bacterial growth were obtained at 30°C, pH = 8 and salinity of 7.5–10 ppt. The hardness of the media suppressed the bacterial growth. In conclusion, AMX was found to be effective against both the planktonic and the biofilm forms of the prominent fish pathogen, S. parauberis.  相似文献   
99.
Enterococci and Salmonella were isolated from feces of chicken in intensive poultry farms and cattle which are maintained following traditional practices. Their resistance to different antibiotics was also determined. A total of 298 enterococcal isolates consisting of Enterococcus faecium (49.6%), Enterococcus durans (26.9%), Enterococcus hirea (11.9%), and Enterococcus faecalis (11.5%) were obtained. Among the enterococci, resistance to erythromycin (Ery), clindamicin (Cli), amoxicillin (Amo), ampicillin (Amp), and cephalothin (Cep) was high. Resistance to vancomycin (Van) was detected in all enterococcal species. Over 80% of the isolates showed multiple drug resistance. The most dominant patterns in poultry were Amo/Amp/Cep/Pen and Amo/Amp/Cep/Cli/Pen/Van. Among isolates from cattle, Amo/Amp/Cep/Cli/Ery/Pen/Van and Amo/Amp/Cli/Ery/Pen/Van constituted the most dominant multiple resistance patterns. A total of 51 Salmonella isolates were obtained from poultry (43/280) and cattle (8/450). About 70% of the isolates had varying resistance to the tested antibiotics. Multiple drug resistance was observed in over 30% of the Salmonella isolates. The most frequent resistance pattern was Amo/Amp/Cip/Gen/Str in cattle and Amo/Amp/Cep/Cip/Gen/Kan/Str in poultry. Enteroccoccal and Salmonella isolates showed multiple resistance to those antibiotics used in human and veterinary medicine. The high frequency of isolation of resistant enterococci is indicative of the wide dissemination of antibiotic resistant bacteria in the farm environment.  相似文献   
100.
Apoptosis occurs during early development in both in vivo‐ and in vitro‐produced embryos, and is considered as one of the causes of embryonic loss. The objectives of this study were, therefore, investigating stage‐specific expression profiles of apoptosis regulatory genes in three quality groups of in vitro‐produced bovine pre‐implantation embryos; and analysing the relationship between cell number and DNA fragmentation with expressions of those genes. The relative abundance of mRNA of 9 pro‐ (Bax, caspase‐9, Bcl‐xs, P53, Caspase‐3 and Fas) and anti‐ (Bcl‐w and Mcl‐1) apoptotic genes was analysed. Differential cell staining and terminal deoxynucleotidyl transferase‐mediated dUTP‐biotin nick end labelling were performed to analyse the variation in cell numbers and detect apoptotic nuclei respectively. Expression of Bax and Caspase‐3 genes was significantly (p < 0.05) higher in poor quality pre‐implantation embryos as compared with that of morphologically good quality embryos of the same developmental stages. Moreover, Mcl‐1 expression was significantly higher in good quality immature oocytes than that in the poor quality group. Moreover, higher DNA fragmentation was evidenced in morphologically poor quality blastocysts. In conclusion, our study demonstrates that Bax, caspase‐3 and Mcl‐1 can be used as potential markers of embryo quality to evaluate in vitro‐produced bovine embryos. Further studies are required to investigate specific molecular signatures that can be used in evaluating in vivo‐derived embryos.  相似文献   
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