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51.
The aim of the present study was to determine the efficacy and the so-called "egg reappearance period" (ERP) of doramectin in horses naturally infected with strongyles during a period of 34 weeks. A group of yearlings of 10 animals was treated intramuscularly with doramectin at a dose rate of 0.2 mg/kg bodyweight (BW) at the begin of the grazing season. To obtain comparable data, another group of yearlings (n = 10) was treated orally with ivermectin at a dose rate of 0.2 mg/kg BW. Individual faecal samples were examined for strongyle egg counts per gram of faeces (EPG) in two-week intervals. Twelve weeks later, a second treatment was given in both groups with the respective anthelmintic followed by a third treatment when the group mean egg count reached > or = 200 EPG. The efficacy of doramectin was > or = 96 % and that of ivermectin 100%, based on the mean egg counts two weeks post treatments (wpt). The highest and the lowest extensity of the efficacy (average values) for doramectin were 90% and 41% two and ten wpt, respectively, whereas these values for ivermectin differed from 100% (two wpt) to 24.3% (eight wpt). The ERP was found to be 10 and 8 weeks for doramectin and ivermectin, respectively.  相似文献   
52.
Changes on the CIELab values of the dyed materials after the different chemical finishing treatments using artificial neural network (ANN) and linear regression (LR) models have been predicted. The whole structural properties of fabrics and some process data which were from fiber to the finishing parameters were accepted as inputs in these models. The networks having different structures were established, and it was also focus on the parameters which could affect the performance of the established networks. It was determined that we could successfully predict the color differences values occurring on the material after the finishing applications. In addition, we realized that some ANN parameters affected the prediction performance while establishing the models. After training ANN models, the prediction of the color difference values was also tried by linear regression models. Then, extra ANN models were established for all outputs using the parameters as inputs in the LR equations, and the prediction performances of both established models were compared. According to the results, the neural network model gives a more accurate prediction performance than the LR models.  相似文献   
53.
In this research, the mineral and organic composition of the seminal plasma, physical spermatological parameters and their physiological relationships were investigated in grass carp (Ctenopharyngodon idella). The seminal plasma contained 98.14±5.23 mM L?1 (Na+), 380.85±25.95 mM L?1 (K+), 30.25±4.96 mg dL?1 (Ca2+), 19.16±1.70 mEq L?1 (Mg2+), 1.36±0.11 mg dL?1 glucose, 0.37±0.08 g dL?1 total protein, 12.02±1.18 mg dL?1 cholesterol, 14.85±1.50 mg dL?1 triglyceride and 43.5±9.56 mg dL?1 urea. The following spermatological parameters were found: sperm volume 14.44±1.16 mL, sperm motility 80.60±1.55%, movement duration 67.68±4.32 s, density 15.43±0.72 × 109 mL?1, total density 337.43+45.86 × 109 and pH 7.24±0.17. The Na+ and Ca2+ ions correlated negatively with spermatozoa motility (r=?0.453, P>0.05 and r=?0.192, P>0.05) respectively. The K+ ion correlated positively with spermatozoa motility (r=0.545, P>0.05). But a statistically significant correlation was not observed between sperm motility and seminal plasma parameters. The following correlations were observed between mineral and organic components. The Mg2+ was positively correlated with glucose and cholesterol (r=0.692, P<0.05 and r=0.680, P<0.05) respectively. A highly significant positive relationship was also found between Mg2+ and total protein (r=0.837, P<0.01). On the other hand, a significantly negative relationship was found between Ca2+ and triglyceride (r=?0.639, P<0.05). These parameters should be considered when developing procedures for either artificial fertilization or for cryopreservation of grass carp sperm.  相似文献   
54.
The development time, survivorship and reproduction ofTuberolachnus salignus (Gmelin) (Hemiptera: Aphididae) [Lachninae, Lachnini] were studied onSalix babylonica (weeping willow) andSalix matsudana (corkscrew willow) at five constant temperatures (17.5, 20, 22.5, 25 and 27.5°C). The development time of immature stages ofT. salignus ranged from 14.56 days at 17.5°C to 12.50 days at 25°C onS. babylonica, and 16.47 days at 20°C to 12.28 days at 25°C onS. matsudana. The total survivorship of immature stages ofT. salignus varied from 28% to 85% at 22.5 and 17.5°C, respectively, onS. babylonica, and from 13% to 63%, respectively, at 17.5 and 25°C onS. matsudana. The greatest intrinsic rate of increase occurred at 25°C onS. babylonica (0.2691) and also onS. matsudana (0.2607). The mean generation time of the aphid population ranged from 14.15 days at 25°C to 16.24 days at 17.5°C onS. babylonica, and from 14.33°C days at 25°C to 19.86 days at 20°C onS. matsudana. The optimal temperature forS. babylonica growth, development time, reproduction and percent survival was 25°C.  相似文献   
55.
以新疆伊犁地区的4类野生杏(野生甜仁杏1号、野生甜仁杏2号,野生苦仁杏1号、野生苦仁杏2号)为材料,研究其在干旱胁迫下渗透调节物质的积累特性.对二年生天山野杏苗进行持续80 d的田间自然干旱处理过程中,每隔20 d取样分析土壤相对含水量(SRWC)及叶片相对含水量(LRWC),Na+,K+和可溶性蛋白质、可溶性糖以及脯...  相似文献   
56.
Ceratocystis platani was detected at several locations in the European side of Istanbul, causing severe dieback and mortality, mainly on Platanus × acerifolia imported from Italy approximately 160 years ago, but also on Platanus orientalis. In the work reported here, the causal agent of the dieback and mortality was identified based on morphological characteristics in culture and internal transcribed spacer (ITS) sequencing, confirming the presence of C. platani in Turkey. All analysed C. platani isolates from Istanbul shared the same ITS sequence with European C. platani strains available in the NCBI, but differed from other species previously ascribed to the Ceratocystis fimbriata species complex. Pathogenicity of C. platani was proven by inoculation onto 25‐cm‐long and 4–9 mm diam. P. orientalis twigs and the causal agent reisolated from symptomatic tissues. In a survey of 976 Platanus in streets and parks of Istanbul, 26.5% of trees showed symptoms of C. platani infections, whilst 5.6% were dead. The proportion of symptomatic trees was higher where management interventions, such as topping or pruning and felling infected trees had been carried out.  相似文献   
57.
Decision support systems (DSSs) are indispensable tools in preparing a forest management plan for a better combination of multiple forest values. This study attempted to develop and explain a stand-based forest management DSS (Ecosystem-based multiple-use forest planning [ETÇAP]) comprising a traditional simulation, linear programming (LP), metaheuristics and geographic information system. The model consists of five submodels; traditional management approach to handle inventory data, an empirical growth and yield model, a simulation to conceptualize management actions, a LP technique to optimize resource allocation and a simulated annealing approach to directly create a spatially feasible harvest schedule. The ETÇAP model has been implemented in a comparative two case study areas; Denizli–Honaz and Akseki–Ibrad?. Both simulation and optimization models outperformed to the traditional management plan. The periodical change of growing stock, allowable cuts, carbon sequestration and water production are used as performance indicators. The results showed that more amount of wood could be harvested over time compared to traditional level of harvesting. It could be concluded that various management strategies allowed managers to stimulate more decision options for better outputs through intertemporal trade-offs of management interventions as the model provided tools to quantify forest dynamics over time and space. Challenges exist to establish the functional relationships between forest structure and values for better quantification and integration into the management plans.  相似文献   
58.
The differences in the ridge structure of the mandibles of different size Astacus leptodactylus (32–80 mm carapace length, CL) were investigated. The results showed that a modification occurs with an increase in size in the incisor ridge of mandibles in A. leptodactylus. The results also showed that A. leptodactylus possesses four different types of ridge structure in the mandibles. These are: (1) Incisor ridge with big teeth (dentate crenate), (2) Blade-like incisor ridge with numerous small teeth, (3) Blade-like ridge (toothless), (4) Blunt ridge. In conclusion, it is thought that the incisor ridge modification of the mandibles may cause the difference in the food choice of different size A. leptodactylus, because, crayfish possessing different ridge structures of the mandible may probably feed on different type of food.  相似文献   
59.
Phthalates such as di‐n‐butyl phthalate (DBP) and their esters are widely used plasticizers, their ubiquitous presence in daily life, inevitably leads to their restricted use due to important environmental pollution and health impacts and endocrine disruption potential. The aim of this study was to examine the effects of a sublethal concentration of 10 mg L?1 DBP on haematocrit (HCT) values, gills and liver histology, malondialdehyde (MDA, 2‐thiobarbituric acid‐TBA reactivity) and reduced glutathione (GSH) levels in gills and liver tissue as oxidative stress biomarkers in the aquaculture fish species Nile tilapia (Oreochromis niloticus) after 24 (DBP‐24) and 96 (DBP‐96) h exposure. No differences were found between per cent HCT values in the 24 h exposure groups (P > 0.05). Response of antioxidant defence systems in liver and gill tissues of the fish were dependent on exposure duration and changed to a higher extent during 96 h. MDA levels in liver tissue increased in DBP treated fish in comparison to the control fish. However, the differences between the exposure and control groups were not significant (P > 0.05). A statistically significant decrease (P > 0.05) was recorded in gill MDA levels in the DBP‐96 group when compared to the control and DBP‐24 groups. The liver GSH levels were unchanged in the DBP treated fish. However, GSH levels were significantly lower in the gill tissue of the DBP‐96 group. Exposure to DBP caused several degenerative changes in the histology of gill and liver tissue. Gills displayed hyperaemia, epithelial lifting, oedema, talengiectasia, epithelial hyperplasia and fusion of secondary lamellae, whereas in liver several circulatory anomalies (hyperaemia, blood congestion and sinosoid dilatation) and vacuolization of hepatocytes were observed. Histopathological results demonstrated that the gills were more affected than the liver perhaps due to their direct contact with DBP.  相似文献   
60.
The aim of the study was to monitor the occurrence of 37 antibiotics from different classes including fluoroquinolone, tetracycline, macrolide, sulphonamide, penicillin, amphenicol and cephalosporin in three different farmed fish species (n = 75; rainbow trout, see bass, gilthead see bream) from five cities in Turkey. A method for LC‐MS/MS was optimized and validated to assess these antibiotics. As a result, 25 samples showed contamination with at least one antibiotic residue. The most detected antibiotics were norfloxacin (NOR) (18.7%), marbofloxacin (MAR) (12%), tetracycline (TC) (10.7), danofloxacin (DAN) (9.3%), oxytetracycline (OTC) (9.3%), tilmicosin (TLM) (8%) and enrofloxacin (ENR) (6.7%). A total of 17.3% of samples examined were found to be contaminated with residues exceeding the maximum residue limits (MRLs). The results indicate that antibiotics are frequently used in aquaculture production without the lack of knowledge. This study also revealed that the consumption of farmed fish could produce a public health concern as the level of residues for some antibiotics was much higher than MRLs.  相似文献   
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