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11.
Abstract

Hollow‐fibre, laminate‐flake and microencapsulated formulations of the synthetic sex pheromone (Z,Z) and (Z,E)‐7–11‐hexadecadienyl acetate of Pectinophora gossypiella (Saunders) were applied aerially in large scale trials in the Delta region of Egypt in 1985. 100 ha blocks of cotton were treated at regular intervals throughout the season as the only means of controlling the pest and compared with a 100 ha block of cotton sited in the same locality which was treated aerially with conventional insecticide spray applications. Comparisons of numbers of infested bolls, open boll counts and yields of seed cotton showed that adequate levels of control were achieved with all three pheromone formulations which were at least as effective as the insecticide sprays. The costs of the pheromone formulations and their aerial application also compared favourably with the insecticide programme. Greater numbers of beneficial insects were recorded in the pheromone‐treated areas than in the insecticide treated area.  相似文献   
12.
【目的】 蝗灾突发性强,传统地面调查及生物学模型方法在时间、空间上不能满足精准防控的需求,且对历史数据依赖度高,利用高分辨率遥感数据监测蝗虫栖息生境的变化,从而实现蝗灾及时、快速监测,对治蝗防蝗具有重要意义。【方法】 文章以埃及南部蝗灾常发区为研究区,基于Sentinel-2卫星数据和地面气象数据、土地利用数据、行政区划数据等,监测植被生长季植被指数及植被覆盖度变化,实现埃及地区蝗虫发生地、发生程度的快速评估。【结果】 2019年6—7月,埃及南部植被覆盖区蝗灾受灾面积比例约为12%,中度及重度以上面积不超6%,整体受灾不严重。【结论】 不依赖于历史数据,从短期植被覆盖度变化入手,可以动态监测蝗灾变化,总体时效性较强、效果较好。  相似文献   
13.
Identification of the risk factors associated with Enzootic bovine leukosis (EBL) is essential for the adoption of potentially prevention strategies. Accordingly, our objectives were to determine the geographic distribution of Bovine Leukemia Virus (BLV) infection and identify the risk factors associated with cow-level BLV infection in the Egyptian dairy cattle. A cross-sectional study was conducted on 1299 mixed breed cows distributed over four provinces in the Nile Delta of Egypt in 2018. The randomly selected cows on each farm were serologically tested for BLV, and the cow’s information was obtained from the farm records. Four variables (geographic location, herd size, number of parities, and age) were used for risk analysis. A total of 230 serum samples (17.7 %) were serologically positive for BLV. The highest prevalence of BLV infection was associated with parity (OR = 3.4, 95 %CI 2.4–4.9) with 80 % probability of being BLV-positive at parity ≥5, followed by herd size (OR = 1.8, 95 %CI 1.4–2.2). However, geographic location seems to have no impact on the prevalence of BLV infection in Egypt. Our findings strongly indicate that the intensive surveillance and effective prevention strategies against BLV infection in Egypt should be provided to multiparous cows with ≥5 parities and live in large farm with more than 200 cows.  相似文献   
14.
Infectious bronchitis (IB) is a highly contagious viral disease and is responsible for considerable economic losses in the poultry industry, worldwide. To mitigate the IB-associated losses, multiple vaccines are being applied in the sector with variable successes and thus necessitating the development of a potent vaccine to protect against the IB in the poultry. In the present study, we investigated a bivalent live attenuated vaccine consisting of IB virus (IBV) strain H120 (GI-1 lineage) and D274 (GI-12 lineage) to evaluate its protection against heterologous variant of IBV (GI-23 lineage) in chicken. Protection efficacy was evaluated based on the serology, clinical signs, survival rates, tracheal and kidney histopathology and the viral shedding. Results demonstrated that administering live H120 and D274 (named here Classivar®) vaccine in one day-old and 14 days-old provided 100 % protection. We observed a significant increase in the mean antibody titers, reduced virus shedding, and ameliorated histopathology lesions compared to routinely used vaccination regimes. These results revealed that usage of different IBV vaccines combination can successfully ameliorate the clinical outcome and pathology in vaccinated chicks especially after booster vaccination regime using Classivar®. In conclusions, our data indicate that Classivar® vaccine is safe in chicks and may serve as an effective vaccine against the threat posed by commonly circulating IBV strains in the poultry industry.  相似文献   
15.
The objective of the present study was to verify the prevalence and the risk factors associated with dermatophytosis in Arabian horses. For this purpose, a total of 457 Arabian horses in 15 farms were examined. A questionnaire was constructed to include the hypothesized risk factors. Fungal isolation and identification for each horse were carried out by standard microbiological procedures. Logistic regression analysis was used to evaluate the risk factors on both animal and farm levels. Trichophyton spp. was recovered from 50 horses and Microsporum spp. from 27 cases. Trichophyton equinum was more prevalent than Trichophyton mentagrophytes (45 vs. 4) and Trichophyton tonsurans (45 vs. 1). However, Microsporum canis was more prevalent than Microsporum gypseum (21 vs. 5) and Microsporum audouinii (21 vs. 1). On horse level, final multivariate logistic regression analysis showed that there was a significant association between dermatophytosis and horse' age (P < .05; odds ratio [OR]: 1.07; 95% confidence interval [CI]: 1.0–2.69), poor grooming practice (P < .05; OR: 57.11; 95% CI: 2.47–13.44), moist condition (P < .05; OR: 42.77; 95% CI: 2.0–25.18), and farm size (P < .05; OR: 1.06; 95% CI: 1.00–7.05). However, on the farm level, farm size of >30 horses was the risk factor (P < .05; OR: 1.0; 95% CI: 1–3.03). In conclusion, the present results indicate existance of dermatophytosis in Arabian horses. Identification of the potential risk factors associated with the disease may be helpful to construct the ideal preventive measures.  相似文献   
16.
West Nile Virus (WNV) is a flavivirus, mosquito-borne infection and have public health importance worldwide. WNV infection have highly significant impact on animal and human health. The virus has been detected serologically in Egypt among equids. Therefore, the aim of the present study to investigate the serological situation of WNV among horse in north of Egypt and identification of WNV in vector. The serological survey was conducted on 500 serum samples that collected from horses from four governorates at north of Egypt. The infection rate was non-significant differed between four localities and the highest rate was reported in Qalyubia governorate (25.5 %) in comparison with other areas. Moreover, the WNV RNA was detected in mosquitoes and the obtained WNV sequence showed high similarity with Eg101 strain and characterized as lineage 1. The obtained findings confirm the circulation of WNV in mosquitoes and animals in Egypt.  相似文献   
17.
For the biological control Bemisia tabaci (Genn.) Biotype B (Homoptera: Aleyrodidae) , about 200,700 individuals of the imported parasitoid Eretmocerus hayati Zolnerowich and Rose (Hymenoptera: Aphelinidae) were released during 2000 and 2002 on different host plants in Egypt. The average parasitism rates in different governorates on Lantana camara, Gossypium barbadence (cotton), Helianthus annus (soybean) and Solanum melongena (eggplant) were 10.3 and 14%, 16 and 11.4%, 12.9 and 8.7%, 18 and 13% during 2001 and 2002, respectively. The population of E. hayati correlated significantly with the buildup of the whitefly population in all three governorates, which indicated the establishment of the E. hayati parasitoid on these economically important crops in Egypt.  相似文献   
18.
[目的]了解在埃及两个不同地区种植的4个有潜力甘蔗品种的最佳收获期.[方法]于2009~2010、2010~2011年度分别在埃及卢克索省El-Mattana研究站(上埃及)和米尼亚省Mallawi研究站(中埃及)进行了两个田间试验,采用裂区设计,3个重复,对4个有潜力的甘蔗品种G95-21、G98-28、G99-160和G99-103的新植蔗分别在不同时间,即(植后)10、11、12和13个月收获,并分别调查农艺性状、甘蔗产量和糖产量.[结果]在(植后)13个月收获时,甘蔗品种G99-103和G95-21的茎高、茎径、茎重、蔗糖分、蔗汁纯度、出糖率、蔗产量以及糖产量最高,且以在卢克索省种植的甘蔗大部分农艺性状表现更优.品种、收获期和种植地点的第一和第二交互顺序显著影响所有甘蔗的农艺性状.[结论]在埃及中上部地区种植甘蔗品种G99-103和G95-2,且在12和13个月株龄时收获,可以获得最高的蔗茎产量和糖产量.  相似文献   
19.
This review discusses the historical, developmental and practices of ostrich farming in Egypt. In the early 20th century, ostrich farming was very important for production of ostrich feathers and documents were produced to perfect the art of procuring the plumes from the birds and subsequently processing them. Pharaohs used ostrich feathers for adornment. Of 43 provinces, 12 were featured in 2003-2004 as farming ostriches: Alexandria, Al-Behera, Al-Dakahlia, Al-Wadi Al-Gadid, Aswan, Cairo, El-Sharkia, Geiza, Ismailia, Kafr-El-Sheikh, Matrouh and Nubaria. Abattoirs and tanneries specialising in ostrich handling are limited to two. Egypt has numerous strengths and opportunities to develop its ostrich sector. Rising meat prices suggest that fresh ostrich meat is unaffordable to many locals. Funds may be allocated to local advertising campaigns to promote ostrich meat; provision of incentives to farmers; and improving the capacity of abattoirs.  相似文献   
20.
This study explores the effects of year and location on reproductive traits and flowering phenology in Retama raetam populations growing in a hyper-arid environment. Besides year, season, and location, variations in the soil seed bank were also evaluated. Germination percentage of seeds buried in soil at two different depths for one year was determined. I hypothesized that changes in water availability between years and locations would lead to variations in reproductive traits, flowering phenology, and the seed bank of R. raetam. The study was conducted at a midstream and an upstream location during 2013 and 2014 in Wadi Rishrash in the Eastern Desert of Egypt. Flower, fruit, and seed production were significantly higher in the midstream location than the upstream location and in 2014 than in 2013. Flowering onset and duration did not differ significantly between locations. Flowering occurred earlier in 2014 than in 2013 at both locations, and the flowering period was longer in 2014 than in 2013. The size of the seed bank was greater at the midstream than at the upstream location, and in summer than in spring season. Germination of seeds decreased with burial depth, but increased with burial duration. Larger individuals produced more seeds and flowered earlier than smaller plants. The size of plant was also positively correlated with flowering duration. The location and temporal variations in all these traits may be related to environmental differences between locations and differences in annual precipitation.  相似文献   
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