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251.
ABSTRACT1. The real burden of Campylobacter spp. in Lebanon is still unknown. The aims of this study were to unravel the epidemiology of Campylobacter spp. in broilers at slaughterhouses in Tripoli, North of Lebanon and to characterise their antibiotic resistance profiles.2. From May to November 2015, sampling was performed through five repeated surveys from 15 slaughterhouses that sold chicken directly to Lebanese customers. Isolates were subjected to pulsed field gel electrophoresis (PFGE) and flaA-restriction fragment length polymorphism (flaA-RFLP).3. All investigated slaughterhouses were found to be positive for Campylobacter spp. Campylobacter coli was the predominant species (38 isolates) followed by C. jejuni (eight isolates). A noticeable level of resistance was detected among isolates against ciprofloxacin (97% of C. coli and 87.5% of C. jejuni), amoxicillin (89% of C. coli and 75% of C. jejuni), gentamicin (79% of C. coli and 50% of C. jejuni), and co-amoxiclav (24% of C. coli and 25% of C. jejuni). Erythromycin and ertapenem resistance were observed only in C. coli with the following percentages 74% and 13% respectively, but not in C. jejuni. PFGE and flaA-RFLP using DdeI as restriction enzyme divided the strains into 27 and 25 types respectively.4. The high observed genetic diversity of Campylobacter spp. revealed the complexity of the spread of this genus in broilers. This study highlighted the pressing need to monitor antibiotic resistance and to ensure food safety from ‘farm to fork’ in Lebanon. 相似文献
252.
玛丽帕·吐达洪 阿不都外力·阿布都热依木 孜来古丽·米吉提 卡依尔·玉素甫 马丽艳木·阿木东 艾尼江·尔斯曼 祖母拉提·阿布都热依木 艾尔肯·热合曼 《干旱区研究》2011,28(6):1071-1080
以西昆仑山2个海拔样点的土样为对象,利用(LB和TSA)2种培养基,基于16S rRNA基因序列的系统发育,采用纯培养法对其可培养细菌多样性进行研究。2样点中共分离到91株细菌,分为25个属,52个种。厚壁菌门(Firmicutes)占总菌数的48.75%,放线菌门(Actinobacteria)占36.25%,γ-变... 相似文献
253.
Sequence-related amplified polymorphism (SRAP), simple sequence repeats (SSR), inter-simple sequence repeat (ISSR), peroxidase
gene polymorphism (POGP), resistant gene analog (RGA), randomly amplified polymorphic DNA (RAPD), and a morphological marker,
Alternaria brown spot resistance gene of citrus named as Cabsr caused by (Alternaria alternata f. sp. Citri) were used to establish genetic linkage map of citrus using a population of 164 F1 individuals derived between ‘Clementine’ mandarin (Citrus reticulata Blanco ‘Clementine) and ‘Orlando’ tangelo’ (C. paradisi Macf. ‘Duncan’ × C. reticulata Blanco ‘Dancy’). A total of 609 markers, including 385 SRAP, 97 RAPD, 95 SSR, 18 ISSR, 12 POGP, and 2 RGA markers were used
in linkage analysis. The ‘Clementine’ linkage map has 215 markers, comprising 144 testcross and 71 intercross markers placed
in nine linkage groups. The ‘Clementine’ linkage map covered 858 cM with and average map distance of 3.5 cM between adjacent
markers. The ‘Orlando’ linkage map has 189 markers, comprising 126 testcross and 61 intercross markers placed in nine linkage
groups. The ‘Orlando’ linkage map covered 886 cM with an average map distance of 3.9 cM between adjacent markers. Segregation
ratios for Cabsr were not significantly different from 1:1, suggesting that this trait is controlled by a single locus. This locus was placed
in ‘Orlando’ linkage group 1. The new map has an improved distribution of markers along the linkage groups with fewer gaps.
Combining different marker systems in linkage mapping studies may give better genome coverage due to their chromosomal target
site differences, therefore fewer gaps in linkage groups. 相似文献
254.
A. M. Osman C. J. M. Almekinders P. C. Struik E. T. Lammerts van Bueren 《Euphytica》2008,163(3):511-522
Main stream commercial onion breeders do not select varieties for organic farming, but solely for conventional farming. Seed
companies consider the organic market too small to justify investments in breeding for this sector. In order to study if their
varieties also suit organic farmers’ needs we interviewed four Dutch commercial onion breeders on their breeding programme
and selection criteria and compared the outcome with a variety profile composed of the priority traits of Dutch organic farmers.
Breeders gave priority to the same storage and bulb quality traits that are demanded by organic farmers, because organic onions
are exported to conventional supermarkets that apply the same quality standards to organic and conventional onions. However,
organic farmers also need varieties that perform well in the field. Breeders give low priority to field selection. Furthermore,
three of the four seed companies only breed hybrids. The cytoplasmic male sterility system used to produce these hybrids does
not comply with organic principles. We conclude that at present breeders can provide varieties that meet organic farmers’
demands for storability and quality traits, but they should give higher priority to field selection to also improve required
field traits. The latter will only occur, if in future the organic seed market will grow. If the organic sector wants varieties
developed according to its own principles, it should either set up its own onion breeding programme or seek alliances with
breeding companies that are prepared to harmonize their breeding methodology with the organic principles. 相似文献
255.
In the current study, African catfish, Clarias gariepinus, was exposed to a sublethal concentration of carbofuran (CF) to investigate its negative effects on biochemical and oxidative stress biomarkers. Also, the putative role of lycopene (LYC) administration in alleviating these negative effects was evaluated. Fish were divided into six groups in triplicates as follows: group I was without treatment, group II was orally administered corn oil, group III was orally administered 18 mg LYC/kg body weight, group IV was exposed to 0.121 mg CF/L, group V was orally administered 9 mg LYC/kg body weight and exposed to 0.121 mg CF/L, and group VI was orally administered 18 mg LYC/kg body weight and exposed to 0.121 mg CF/L for 4 weeks. At the end of this period, blood and tissue (liver and kidney) samples were collected and biochemical and oxidative stress biomarkers were analysed. Also, histopathological changes were determined. Carbofuran caused significant increments of glucose, cortisol, aspartic amino transferase, alanine amino transferase, cholesterol, urea, and creatinine; meanwhile, serum acetylcholinesterase, total protein, albumin, and total lipids were significantly reduced. Significant increments in hepatic and renal malondialdehyde (MDA) and superoxide dismutase (SOD) levels and marked reduction in hepatic and renal catalase (CAT), glutathione (GSH), and total antioxidant capacity (TAC) levels were observed in CF-exposed fish comparing to the control group. Treatment with LYC attenuated the CF-induced oxidative stress, and this improvement was more pronounced in fish received the high LYC dose (18 mg/kg body weight). Further, congestion of the central vein with infiltration of mononuclear inflammatory cells, vacuolar necrosis, and haemorrhage was observed in the livers of CF-exposed fish. Oral administration of LYC reduced behavioural changes and histopathological alterations. All the altered biochemical parameters and antioxidant biomarkers were also restored to be near the normal levels. The obtained results evoked that LYC administration alleviated the destructive effects of carbofuran and reduced its toxicity effect on African catfish. 相似文献
256.
Pre‐challenge and post‐challenge haemato‐immunological changes in Oreochromis niloticus (Linnaeus, 1758) fed argan oil against Lactococcus garvieae 下载免费PDF全文
Esin Baba Ümit Acar Sevdan Yılmaz Canan Öntaş Osman Sabri Kesbiç 《Aquaculture Research》2017,48(8):4563-4572
The present study investigated the effects of argan oil, obtained from Argania spinosa, on pre‐ and post‐challenge immuno‐haematological and biochemical responses of Nile tilapia, Oreochromis niloticus. For this purpose, the fish were fed diets containing 0, 0.5%, 1% or 2% argan oil for 45 days. Following 45 days of feeding, fish were challenged with Lactococcus garvieae and mortality was recorded for 15 days. During the pre‐challenge period, significantly higher respiratory burst activity, total white blood cell (WBC), serum lysozyme activity and myeloperoxidase activity were determined in the argan oil‐fed groups. The serum glucose and cholesterol levels decreased whilst total protein and albumin did not change in the groups fed with argan oil‐supplemented diets. After challenge with Lactococcus garvieae, the percentage survival (%) was found to be the highest in the 1% and 2% argan oil‐supplemented feeding groups. Also, there was a significant increase in weight gain, specific growth rate and feed conversion ratio in those fish fed argan oil. The results of this study indicated that after the supplementation of fish diets with argan oil, especially at 1% and 2% concentrations, the immunological, haematological and biochemical values remained similar in both the pre‐ and post‐challenge periods and the immune response against L. garvieae in Nile tilapia was modulated. 相似文献
257.
Musa Bulut Murat Yiğit Sebahattin Ergün Osman Sabri Kesbiç Ümit Acar Nejdet Gültepe Mustafa Karga Sevdan Yılmaz Derya Güroy 《Aquaculture International》2014,22(3):965-973
The objective of this study is to investigate the effects of dietary protein and lipid levels on the growth performance and bioeconomic benefits of two-banded seabream (Diplodus vulgaris) juveniles, a candidate species for aquaculture sector. Eight experimental diets were formulated with four protein (50, 45, 40 and 35 %) levels for each of the two lipid levels (15 and 10 %). Triplicate groups of juvenile fish with an average initial body weight of ~3.64 g were reared in a recirculating aquaculture system and hand fed twice a day until satiation for a period of 60 days. In the experiment, no difference in survival rate was found between the different groups. Relative growth rate (RGR), specific growth rate (SGR), feed conversion ratio (FCR) and daily feed intake were not significantly affected by increasing protein and/or lipid treatments in this present study. However, the RGR, SGR and FCR values showed slightly better efficiency in the experimental group (35/15) fed with lower protein content (35 %) and higher lipid level (15 %) compared with those fed other diets. According to bioeconomic analyses results, the diet with the 35 % protein and 15 % lipid generated the best profit. The results suggest that two-banded seabream can be accepted as a promising alternative species for the aquaculture industry and optimum growth of two-banded seabream fingerlings can be obtained when they are fed a diet containing 35 % crude protein and 15 % crude lipid. 相似文献
258.
Osman Inanç Güney 《Journal Of Aquatic Food Product Technology》2019,28(2):210-220
This study investigated consumers’ motivations and perceptions of fish obtained from different production methods, namely wild or farmed. Data were collected from 526 consumers via face-to-face interviews in the seven regions of Turkey. A logistic regression model was designed for the consumers of different fish production methods. Results of the study demonstrate that consumers perceive wild and farmed fish differently. Furthermore, consumers have different perceptions of the following factors that also effect consumption: convenience, variety, origin, confidence, accessibility, freshness, and reliability. 相似文献
259.
260.
The availability of land and water resources in a diversity of climatic zones provides Sudan with a vast potential to produce many tropical and subtropical fruits. Bananas, dates, guavas, mangos, and citrus are the major fruits produced on a commercial scale. Fruit growing is mostly limited to enterprises ranging from 1–40 ha. Fruits of indigenous wild fruit species play an important role in the diet of people in the savanna belt, especially during famines and food shortages. Local varieties are grown in many fruit-producing areas. They are well adapted to the local environment but of low-to-medium market quality and productivity. Research and international cooperation are necessary and promising for future development of the fruit-producing sector in Sudan. 相似文献