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71.
Oğuz Kul Nalan Kabakci Kader Yildiz Naci Öcal Hakan Kalender N. Aycan İlkme 《Veterinary parasitology》2009
Neospora caninum, a protozoan parasite, has been considered as one of the most important etiological agents responsible for abortion in dairy cattle throughout the world since it was first identified in dogs in 1988. In this report, characteristics of neosporosis, detected in a dairy cow ranch having epidemic abortions as high as 18.4%, were described. Blood samples were collected from 25 infertile or aborted dairy cattle, 6 calves born in 2006 and 40 heifers that were born in 2005 and raised in the same ranch. Necropsy was conducted in a 20-day-old Simmental calf that exhibited neurological signs including incoordination, head shaking, hyperextension in forelimbs and hindlimbs and tremor. The seroprevalance in aborted or infertile dairy cattle, heifers, and calves was 60%, 40%, and 33.3%, respectively. The mothers of seropositive two calves including clinically affected calf and its dam were N. caninum seropositive. In immunoperoxidase examinations, N. caninum antigen immunopositivity was observed in the degenerative and necrotic neurons in the brain, cerebellum as well as neurons in dorsal root ganglia of the cervical and thoracic regions of the spinal cord. In the heart, myocytes and Purkinje cells exhibited granular and linear patterns of immunoreactivity. Striated myofibers around the eyeball also showed immunolocalization for N. caninum antigen. Ultrastructurally, tachyzoites with typical apical complex, rhoptries and double-layered parasitic membrane were detected in the brain and heart sections. In conclusion, this report described clinical neosporosis for the first time in Turkey with tissue localization of the causative agents. This scientific communication also discusses the possible impact of cattle neosporosis by clinical, serologic and pathologic evidences collected from the survey of calves born in two successive generations in a ranch. 相似文献
72.
The effect of thinning on microbial biomass C, N and basal respiration in black pine forest soils in Mudurnu, Turkey 总被引:1,自引:0,他引:1
İlyas Bolat 《European Journal of Forest Research》2014,133(1):131-139
Reducing the canopy cover (e.g., forest thinning) is one of the most commonly employed forest silvicultural treatments. Trees are partially removed from a forest in order to manage tree competition, thus favoring the remaining and often the most valuable trees. The properties of the soil are affected by forest thinning as a result of changes in key microclimatic conditions, microbial communities and biomass, root density, nutrient budgets and organic matter turnover. The aim of this study was to determine the soil microbial biomass C, N and respiration (basal respiration) in a black pine (Pinus nigra Arn. subsp. pallasiana) forest in the Mudurnu district of Bolu Province (Western Black Sea Region, Turkey). Whereas forest thinning was found to cause increases in the soil temperature, microbial biomass C and N and organic C, it was found to decrease the soil moisture, basal respiration and metabolic quotient (qCO2). As expected, soil organic C exhibited a strong impact on soil microbial biomass C, N and basal respiration. It was concluded that the influence of forest thinning on the microbial biomass and soil respiration was the combined result of changing microclimatic conditions and soil properties, such as forest litter, soil temperature, soil moisture, soil pH and soil organic matter. 相似文献
73.
Arterial vascularisation of the ovine pineal gland was investigated by latex injection preparations of the common carotid artery in 20 adult Akkaraman sheep brains under stereo light microscope. It was observed that the arterial supply comes exclusively from branches of the caudal cerebral artery. The pineal gland was found to contain a rich vascular network. This network also received a few branches from the caudal choroid rami. 相似文献
74.
Mehmet Serhat Odabas Chiwon W. Lee İsmail İseri 《Communications in Soil Science and Plant Analysis》2017,48(2):162-169
Nitrogen is an essential nutrient for greenhouse-grown lettuce (Lactuca sativa L.); however, excessive nutrient availability causes disease and detrimental effects on the leaf and root development. In this study, nitrogen content of the lettuce leaves was estimated by determining the chlorophyll concentrations of the leaves using image processing technique. The Hoagland solution was used as a fertilizer in five different doses (control, quarter of the solution, half of the solution, standard solution, and two times more of the solution). Multilayer perceptron neural network (MLPNN) model was developed based on the red, green, and blue components of the color image captured to estimate chlorophyll content and chlorophyll concentration index (SPAD values). According to the obtained results, the MLPNN model was capable of estimating the lettuce leaf chlorophyll content with a reasonable accuracy. The coefficient of determination was 0.98, and mean square error was 0.006 in validation process. 相似文献
75.
AbstractThis study aimed to assess the efficiencies of composts and vermicomposts obtained from two different composting methods on the growth, mineral nutrition and nutrient uptake of wheat. Composts and vermicomposts were applied to plastic pots under greenhouse condition with the application doses of 0, 5, 10, 20, and 40 t ha?1. The pot-experiment lasted three months. The results showed that plant dry weight increased with the increase in doses when compared to the control groups where no composts and vermicomposts were applied. However, no differences were found among the doses from 5 to 40 t ha?1 of composts and vermicomposts. Although application doses did not affect significantly on the most of the plant nutrient concentrations, Fe concentration in plant decreased with the increase in application doses. Additionally, no significant differences among the composts and vermicomposts on plant nutrient concentrations except for Mg were detected. Comparing to the control dose (0 t ha?1), nutrient uptakes by plant from the soil significantly increased with the increase of application doses, but no significant differences were determined amongst the doses of 5 and 40 t ha?1, generally. The effect of production methods on the most of investigated parameters including plant dry weight was similar. 相似文献