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151.
J. Alber A. El‐Sayed C. Lmmler A. A. Hassan M. Zschck 《Zoonoses and public health》2004,51(4):180-184
Streptococcus uberis, a well‐known bacterial pathogen associated with bovine mastitis, appears to be biochemically and serologically almost indistinguishable from the closely related species Streptococcus parauberis. In the present study, species‐specific oligonucleotide primers were designed using internal parts of the genes sodA, encoding superoxide dismutase A, and cpn60 encoding chaperonin 60 of S. uberis and S. parauberis, respectively. The two oligonucleotide primer pairs allowed a rapid and reliable PCR‐mediated identification and differentiation of both species. These studies, performed with S. uberis and S. parauberis reference cultures and clinical isolates from routine diagnostics, revealed that the occurrence of S. parauberis as causative agent of bovine mastitis appears to be rare. In addition the sodA and cpn60 sequence data confirmed that both species could taxonomically be classified to the pyogenic group of genus Streptococcus. 相似文献
152.
This paper describes the first threats of H5N1 avian influenza outbreaks in Egypt recorded from February to December 2006 in commercial and domestic poultry from different species and summarizes the major characteristics of the outbreak. There were 1024 cases from different poultry species (rural and commercial chickens of different breeding types, turkeys, ducks, geese, and quail) either in commercial breeding or in backyards from different locations in Egypt. All tested positive for the H5N1 subtype. From these cases only 12 avian influenza A viruses were isolated and characterized from samples collected during outbreaks. All isolates were characterized, and the data confirmed that the isolated viruses belong to highly pathogenic avian influenza of subtype H5N1. Full hemagglutinin (HA) gene (segment 4) sequencing was also done, and the sequences of these isolates were compared with other strains from Russia, Africa, and the Middle East. The data revealed that all Egyptian strains were very closely related and belonging to subclade 2.2 of the H5N1 virus of Eurasian origin, the same one circulating in the Middle East region and introduced into Africa at the beginning of 2006. This study showed evidence of the wide spread of H5N1 virus infection in domestic poultry in Egypt within a short time. The most obvious features of these outbreaks were severe clinical signs and high mortalities as well as very rapid and widespread occurrence within the country in a very short time. The possible causes of its rapid spread and prospects of disease control are discussed. 相似文献
153.
Hassan SM El-Gayar AK Cadwell DJ Bailey CA Cartwright AL 《Veterinary parasitology》2008,157(1-2):133-138
Guar meal contains relatively high levels of saponins, which are known to have antiprotozoal activity and may be effective against coccidiosis. A 2x2 factorial experiment investigated the impact of guar meal (0 or 5%) corn-soy-based starter broiler diets on chicks unchallenged or challenged with Eimeria tenella. At 1 day of age, 120 unsexed RossxRoss broiler chicks were randomly distributed among four treatment groups. Chicks were challenged with 5x10(3) sporulated oocysts of E. tenella in 0.5ml at 10 days of age by oral gavage. Weekly body weight, body weight gains, feed conversion ratio and mortality rate were recorded for chicks fed from 0 to 21 days of age. Oocysts shed per gram feces were recorded from 6 to 10 days post-challenge. Results showed that challenged chicks fed 0% guar meal had significantly higher oocysts per gram shed in feces than the other groups. No significant differences among treatment groups in mortality rate were observed. Body weights of unchallenged and challenged chicks fed 0% guar meal were significantly higher than those fed 5% guar meal at 2 weeks of age. Results indicated that including 5% guar meal in the diet of chicks challenged with E. tenella decreased oocysts shed per gram feces and prevented bloody diarrhea, but without affects on body weight and feed conversion ratio at 11 days post-challenge. 相似文献
154.
Boussakouran Abdelali Sakar El Hassan El Yamani Mohamed Rharrabti Yahia 《Journal of Crop Science and Biotechnology》2019,22(4):345-353
Journal of Crop Science and Biotechnology - Drought is one of the main environmental factors affecting grain yield and plant architecture in durum wheat. The present work was conducted to evaluate... 相似文献
155.
Kadanthottu Sebastian Joseph Sushma Bolla Kavita Joshi Medha Bhat Krupa Naik Sridevi Patil Sreevani Bendre Brunda Gangappa Vidya Haibatti Shivanand Payamalle Smita Shinde Yaser Hassan Dewir Hosakatte Niranjana Murthy 《Erwerbs-Obstbau》2017,59(3):195-202
African mangosteen (Garcinia livingstonei T. Anderson) is native to Africa and is exotic to other parts of the world. It is a fruit bearing tree with multiple uses. This study was purposed to determine, by analysis, the chemical compositions and nutritive value of the fruits of African mangosteen. Proximate compositions varied with the portions such as epicarp, mesocarp, endocarp and seed tested. All fruit portions contained carbohydrate (37.67–95.02%) and crude protein (0.65–31.76%) as their major components. Moisture (0.45–3.42%), crude fat (1.23–19.55%), crude fiber (2.93–21.13%) and ash (1.76–5.44%) were also found at different levels, depending upon the portions. All portions of fruit were rich in macro and micro elements. The fruits also possessed phenolics (174.02–10.725?mg GAE per g), flavonoid (19.25 to 99.98?µg QE per g) and alkaloid (1.56 to 9.49?mg/kg) contents. The constitution of tannins and oxalate which contribute towards the anti-nutritive value was also low, thus making the fruits beneficial for consumption. Quality attributes like relative amount of oleic acid, total unsaturated fatty acid, acid value, free fatty acid, peroxide value and iodine value showed that the seed oil of African mangosteen can become one among the oleic acid based vegetable oils for consumption. 相似文献
156.
Diaeretiella rapae (M’Intosh.) is an endoparasite of the turnip aphid,Lipaphis erysimi (Kalt.) with a wide geographical distribution. The four Pesticides Nogos 50 EC at 600 ml per acre, Dimecron 50 WSC, Monofos
40 WSC and Tamaron 600 SL at 500 ml per acre, used in practice for the control of this pest, were tested for their side-effects
onD. rapae. The parasitoid was reared on pottedBrassica napus plants infested with aphid under laboratory conditions (22±2°C, 60–70% rel. hum., 16 h light and 8 h dark). In one test,
adult female parasitoids were exposed to fresh pesticide residues on glass plates and in another test, the pupae within aphid
mummies were directly sprayed. The results revealed that Dimecron 50 WSC, Nogos 50 EC and Monofos 40 WSC were harmful causing
100% mortalitv toD. rapae followed by Tamaron 600 SL (97% moderately harmful) after 24 hours of application, compared to no mortality in control, where
only water was sprayed. Directly spraying of pupae with Dimecron 50 WSC and Nogos 50 EC reduced adult parasitoid emergence
to 9 and 7%, respectively, Monofos 40 WSC and Tamaron 600 SL to 3% compared to 78% emergence for the control within one week
of treatment. The results showed that none of the tested pesticides was safe toD. rapae and according to the International Organization for Biological Control (IOBC) further testing under semi-field and field
conditions is recommended. 相似文献
157.
Effect of quorum quenching bacteria on growth,virulence factors and biofilm formation of Yersinia ruckeri in vitro and an in vivo evaluation of their probiotic effect in rainbow trout
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Somayeh Torabi Delshad Siyavash Soltanian Hassan Sharifiyazdi Peter Bossier 《Journal of fish diseases》2018,41(9):1429-1438
Five N‐acyl homoserine lactone‐degrading bacteria (quorum quenching (QQ) strains) were selected to evaluate their impacts on growth, virulence factors and biofilm formation in Yersinia ruckeri in vitro. No difference was observed among the growth pattern of Y. ruckeri in monoculture and coculture with the QQ strains. To investigate the regulation of virulence factors by quorum sensing in Y. ruckeri, cultures were supplemented with 3oxo‐C8‐HSL. The results indicated that swimming motility and biofilm formation are positively regulated by QS (p < 0.05), whereas caseinase, phospholipase and haemolysin productions are not influenced by 3oxo‐C8‐HSL (p > 0.05). The QQs were able to decrease swimming motility and biofilm formation in Y. ruckeri. QQ bacteria were supplemented to trout feed at 108 CFU/g (for 40 days). Their probiotic effect was verified by Y. ruckeri challenge either by immersion or injection in trout. All strains could significantly increase fish survival with Bacillus thuringiensis and Citrobacter gillenii showing the highest and lowest relative percentage survival (RPS) values (respectively, 85% and 38%). Besides, there was no difference between the RPS values by either immersion or injection challenge expect for B. thuringiensis. The putative involvement of the QQ capacity in the protection against Yersinia is discussed. 相似文献
158.
Md Mahbubul Hassan Md Nahiduzzaman Shaheed Nasrullah Al Mamun Md Abu Taher Mostafa Ali Reza Hossain 《Aquaculture Research》2013,45(1):150-158
This study reports on the spermatological properties, and on the development of a protocol for refrigerator storage (4°C) of Labeo calbasu (Hamilton, 1822) sperm for artificial breeding. Volume, motility, concentration and pH of the freshly collected sperm were 2.21 ± 0.53 (μL g?1 of fish weight) (mean ± SD), 95 ± 1 (%), 1.93 ± 0.44 × 109 (cells mL?1) and 7.56 ± 0.17 respectively. Sperm activation was evaluated at different osmolalities of NaCl solution, and motility ceased completely when osmolality of the extender was ≥287 mOsmol kg?1. Sperm retained motility for 24, 72 and 108 h, after refrigerator storage when sperm were undiluted, suspended in Alsever's solution and suspended in Alsever's solution containing 5% methanol respectively. Fertilization rate of fresh eggs with sperm stored at 4°C in Alsever's solution and Alsever's solution containing 5% methanol was 77% and 60% with a hatching rate of 60% and 43% respectively. The fertilization and hatching success of the stored sperm suggests potential to use refrigeration for transporting genetic material to hatcheries for artificial breeding of L. calbasu in Bangladesh. 相似文献
159.
Water saving and economic impacts of land leveling: the case study of cotton production in Tajikistan 总被引:1,自引:0,他引:1
Iskandar Abdullaev Mehmood Ul Hassan Kahramon Jumaboev 《Irrigation and Drainage Systems》2007,21(3-4):251-263
Water conservation is essential to prevent salinity and land degradation in Central Asia. Therefore, field-testing and evaluation of water conservation methods, i.e. laser land leveling in new farming systems of Central Asia is important task. This in mind the International Water Management Institute (IWMI) and its regional partner on IWRM FV (IWRM FV project – Integrated Water Resources Management in Ferghana Valley project is funded by Swiss Development Cooperation (SDC) and conducted jointly with IWMI and Scientific Information Center of Interstate Coordination Water Commission (SIC ICWC) in the Ferghana Valley of Central Asia) project SIC ICWC have conducted 3 year study of impacts of the Laser leveled land leveling on water use, productivity and crop yields in northern Tajikistan. The major research question was laser land leveling an effective water saving tool in the new context of land use and ownership on smaller private plots. Can farmers afford the costs of laser land leveling and how economically viable is it? These research questions were studied in 5 ha laser leveled and neighboring non-leveled (control) fields for 2004–2006. The results showed that laser land leveling can reduce the water application rate in 2004 by 593 M3/ha, in 2005 by 1509 M3/ha and in 2006 by 333 M3/ha in comparison with the unleveled field, located in the similar agro-ecological conditions. The deep percolation was 8% lower and run off 24% less than in non-leveled field. The average annual net income from the laser field was 22% higher than that from the control field. The gross margin from the laser-leveled field were 16. 88 and 171% higher compared to that from the control field for 2004, 2005 and 2006, and on average was 92% higher. In spite of these positive results, there are hindrances on wide application of laser land leveling in Tajikistan. These are absence of initial capital of farmers and scattered land location. 相似文献
160.
Seyed Reza Tabaei-Aghdaei Alireza Babaei Morteza Khosh-Khui Kamkar Jaimand Mohammad Bagher Rezaee Mohammad Hassan Assareh Mohammad Reza Naghavi 《Scientia Horticulturae》2007
Forty landraces of Damask rose were collected from 28 provinces (13 origin sites) in Iran and evaluated to determine the diversity among them. The investigated characters were: flower weight, flower diameter, peduncle length, number of petals, number of stamens and oil content. Pearson's coefficients showed that number of petals was positively correlated with flower weight (r = 0.642) and number of stamens (r = 0.630), while its correlation with peduncle length was negative (r = −0.53). A negative correlation was obtained between oil content and number of stamens (r = −0.60) which is useful for indirect selection of landraces with low number of stamens and therefore high amount of oil content. Cluster analysis based on five botanical characters and oil content separated the origin site 12, which included Guilan, Mazandaran and Golestan provinces with a specific climate condition of temperate humid, from other origin sites. This distinctiveness was already confirmed by the bi-plot of the principal components. The distribution of Damask rose landraces provided useful information for the future collection and for the genetic resource management in these origin sites. 相似文献