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111.
The rapid immunofilter paper assay (RIPA) was developed to detect Tomato spotted wilt virus (TSWV), Groundnut ringspot virus (GRSV), and Tomato chlorotic spot virus (TCSV) using antisera against recombinant nucleocapsid (N) proteins of each tospovirus. The two-step RIPA was sensitive enough to detect each pecies specifically in only 30min. This technique is proposed as an excellent tool for routine Tospovirus diagnosis and field epidemiological studies.  相似文献   
112.
The impacts of fermentation process with acid and lactic acid bacteria strains (Lactobacillus plantarum, Lactobacillus brevis, Pediococcus acidilactici, Enterococcus gallinarum, and Streptococcus spp.) on the biogenic amine formation of wet and spray-dried fish silage obtained from whole gibel carp (Carassius gibelio, freshwater discard), whole ponyfish (Equulites klunzingeri, seawater discard), and processing by-products of seabass (Dicentrarchus labrax) were investigated. The results showed that among biogenic amines, cadaverine, putrescine, spermidine, spermine, serotonin, dopamine, and agmatine were predominant in all groups. Significant differences (p < 0.05) in biogenic amine concentrations of wet and spray-dried fish silage were observed. Raw fish and wet silages contained histamine level lower than the allowable limit of 50mg/kg, indicating the use of raw fish material with low microbial counts. In addition, no histamine was detected in spray-dried fish silage, except for seabass by-products with a trace quantity of histamine (<0.04mg/100g). The starter culture used for silage preparation did not effectively retard formation of biogenic amines compared to acid silage. It can be concluded that there is potential use of fermented fish silage as a protein source and possibly as a probiotic ingredient for animal feed in both wet and dry form.  相似文献   
113.
In this study, the effects of cypermethrin on antioxidant status, oxidative stress biomarkers, behavior, and mortality in the freshwater mussel Unio elongatulus eucirrus were examined. Cypermethrin was applied at concentrations of 5, 10, 20, 40, 80, and 160 μg/L, for 1, 24, 48, 72, and 96 h. With increasing cypermethrin concentrations, the mussels showed significantly (P < 0.05) increased lipid peroxidation (MDA), which might be associated with decreased levels of reduced glutathione (GSH) and catalase (CAT) activity in the digestive glands and gills of the mussels. Negative correlations were observed between the MDA and the GSH and CAT levels after cypermethrin exposure, indicating a protective role of GSH and CAT against lipid peroxidation, and suggesting the use of these antioxidants as a potential biomarker of toxicity associated with contaminant exposure in freshwater mussels. In addition, at 5 μg/L, cypermethrin had no effect on the duration of the active and rest periods. All higher concentrations caused inhibition of the filtration activity by reducing the active periods and lengthening the rest periods. The active periods shortened as the cypermethrin concentrations increased, the reduction being 90% of the control at 160 μg/L. Rest periods were longest (237% longer than the control) at 160 μg/L. The 48, 72, and 96 h LC50 values of cypermethrin for mussels were determined as 96.50, 77.96, and 59.20 μg/L, respectively (P < 0.05). The results indicate that the insecticide cypermethrin has a harmful effect not only on nontarget aquatic arthropods and fish, but also on mollusks, although the sensitivity of mussels is less than that of fish. Being a general toxicant for aquatic life, cypermethrin should be used with great caution in agriculture to protect natural waters from contamination.  相似文献   
114.
Very limited information is available on the origin, diversity and evolution of Plum pox virus (PPV) ‘Turkey’ (T) strain. Phylogenetic analyses based on partial sequences of 421 isolates and complete genome sequences of 57 isolates, representing the geographical distribution of PPV-T in Turkey, revealed the existence of several monophyletic and, in some cases, geographically limited groups within the PPV-T strain (Ankara-Konya1-Kayseri, Ankara-Balkan, Istanbul, Konya2 and Balkan). PPV-T diversity (0.018%) was found to be greater than that of PPV strains D and Rec but lower than that of the M strain when including the newly described and divergent M-Istanbul isolates, suggesting a long evolutionary history for PPV-T. The European part of Turkey in the Balkans, close to Bulgaria where PPV was identified for the first time, appears as a likely centre of origin for PPV-T isolates. The colonization of various parts of Turkey by diverse isolates from that region, followed by secondary local spread, is the most likely scenario for the diffusion of PPV-T in Turkey.  相似文献   
115.
Dothistroma needle blight (DNB) is a serious disease of the Pinaceae, mainly Pinus species, caused by the fungi Dothistroma septosporum and D. pini. Both species are regarded as invasive forest pathogens worldwide, with rising incidence in central and northern Europe over the last three decades. In this work, 29 sites were investigated between 2013 and 2015 in south-western Turkey. Morphological examination of needles confirmed DNB infection (i.e., Dothistroma conidiospores observed) at 18 sites, and a total of 108 Dothistroma sp. isolates were obtained from 11 of the sites. Host age seemed to be an important factor in both occurrence and severity of DNB in Pinus brutia forests. Continuous rainy days, especially in December, may increase severity of disease; however, extreme rain events may reduce available conidiospores on plant tissues or in the air. Species-specific mating type primers showed that all isolates were D. septosporum; D. pini was not detected. The mating type ratio was close to 1:1, indicating sexual recombination was occurring. Eleven microsatellite markers revealed 59 unique multilocus haplotypes (MLHs) among the 73 isolates originating from different conidiomata. The majority of MLHs were represented by a single isolate (n = 52) and only one MLH was shared between two localities. Analyses showed high genetic diversity, isolation-by-distance, and clear population clusters. These findings suggest that D. septosporum is well established in south-western Turkey and is probably not a recent introduction.  相似文献   
116.
In this study, we have investigated the effects of Porphyridium cruentum (Rodophyta) as a natural pigment source and astaxanthin and β-carotene as synthetic pigment sources on the skin colour of cichlid fish (Cichlasoma severum sp., Heckel 1840), which are generally light orange with white patches and becomes shiny orange in the reproductive phase. The fish were fed diets containing 50 mg kg−1 astaxanthin and β-carotene, and P. cruentum powder. The amount of both natural and synthetic pigment sources given as feed was 50 mg kg−1, and the experiment was continued for 50 days. Total carotenoid content of the fish was determined spectrophotometrically at the end of the experiment. As a result, while a visible change of colour in the skin of the fish fed on the feed containing astaxanthin was observed with 0.34 ± 0.2 mg g−1 of pigment accumulation, a relatively small change of colour was observed in the skin of other fish that were fed on the feed containing P. cruentum and β-carotene with 0.22 ± 0.2 mg g−1 and 0.26 ± 0.1 mg g−1 of pigment accumulations, respectively. Therefore, it was determined that these pigment sources have an effect on the colour of cichlid fish.  相似文献   
117.
A group of 24 wild starlings (Sturnus vulgaris), in undefined age categories but at least post-pubertal, constituted the material of this study. Six starlings were kept as a control group and 18 starlings served as the infection group. The starlings in the infection group were infected with inoculums of 1.35 x 10(6)/0.2 ml Aspergillus fumigatus via intratracheal route whereas the control group was administered only placebo in the same way. Six, four, two, four and two birds died on 2, 3, 4, 5 and 6 days post inoculation respectively. At the necropsy of the dead birds, caseous foci were determined in the lungs, on the air sacks, myocardium, thoracic wall and abdominal serosa. In the histopathological examination of the white-yellowish caseous foci ranging from pinhead to chick pean in size, necrotic granulomatous foci consisting of macrophages, heterophil leukocytes and gigant cells encapsulated with a fibrous tissue were observed. Hyphae and spores of A. fumigatus were determined in these foci using the Gridley staining method.  相似文献   
118.
119.
ABSTRACT

1. Two consecutive trials were conducted to evaluate the effects of guanidinoacetic acid (GAA) supplementation (a creatine precursor) and energy levels in broiler diets based on maize-soybean meal (Trial 1) or that additionally included poultry by-product meal (PBPM; Trial 2) on growth performance, carcass yield and breast meat quality to 41 days of age.

2. A total of 792, one-day-old male Ross 308 broiler chickens were randomly distributed into six treatments – three energy levels (sufficient AMEn or 0.2 and 0.4 MJ/kg reduced AMEn) and two GAA levels (0.00% or 0.06%) with eight replicates for each trial.

3. Reducing dietary energy resulted in poorer body weight gain (BWG) and feed conversion ratios (FCR) for each trial (P < 0.05). However, GAA supplementation improved FCR, BWG and European Production Efficiency Factor (EPEF) (P < 0.05).

4. Dietary energy level and GAA addition had no significant effect on carcass parameters, drip loss, pH and chemical composition of breast meat (P > 0.05), but decreased relative liver weight (P < 0.05).

5. It was concluded that, regardless of dietary energy levels, supplementation of GAA to plant-based diets or those including PBPM has the potential to improve growth performance in broilers.  相似文献   
120.
In this study, effect of ellagic acid on some haematological, immunological and antioxidant parameters in the blood and various tissues of rainbow trout (Oncorhynchus mykiss) were examined. Four groups of rainbow trout were fed experimental diets containing either no ellagic acid (control) or supplemented with ellagic acid at 50 mg/kg diet (EA‐50), 100 mg/kg diet (EA‐100) or 150 mg/kg diet (EA‐150) for 21 days. Samples of the blood and tissue (liver, kidney and spleen) were collected at the end of the experiment and analysed for their haematological profile (the red blood cell count, the haemoglobin concentration and the haematocrit level), immune response (the white blood cell count, the oxidative radical production (NBT activity), the total plasma protein and total immunoglobulin level) and oxidant/antioxidant status (the malondialdehyde level, the superoxide dismutase, catalase and glutathione peroxidase activity as well as the reduced glutathione concentration). The findings of this study demonstrated that ellagic acid had a positive effect on the haematological parameters, the immune response and the antioxidant enzyme activities of the fish.  相似文献   
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