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51.
A 2-month-old mix-breed calf developed acute blindness and ataxia. Serum thiamine concentration was deficient. In antemortem magnetic resonance imaging there were laminar T2-hyperintense regions extending along the cerebral cortex that primarily affected the gray matter. The lesions were relatively symmetric between the left and right hemispheres but no abnormalities were present at the frontal lobes. At necropsy, laminar autofluorescence of the cerebral cortex was observed under ultraviolet exposure at 365 nm, consistent with a diagnosis of polioencephalomalacia. Polioencephalomalacia in the bovine species is compared with that in other species, namely humans, dogs, and cats.  相似文献   
52.
The purpose of this work was to determine a radiographic standard of normality for lateral and medial ungulae in 3‐year‐old bovine females of the Nellore breed. Twenty‐six cows underwent radiographic exposure of the medial and lateral ungulae of the hindlimbs and forelimbs; abaxioaxial projections were used. The images were analyzed; distances were measured between the dorsal surface of the distal phalanx and the surface of the hoof capsule. The two angles formed, i.e., an angle between the dorsal surface of the distal phalanx and a line parallel to the sole (inner), and an angle between the dorsal surface of the hoof and a line parallel to the sole (outer), were also recorded. The results suggested a standard of normality for the proximal, middle and distal distances of the ungulae of the forelimbs: 0.96 ± 0.12 cm. For the measurement of hindlimbs, except for the distal distances of the side ungulae, the suggested value was 1.02 ± 0.14 cm; for the distal measurement of the lateral ungulae of the hindlimbs, the value was 1.09 ± 0.12 cm. For inner and outer angles, the values were 36.45° ± 4.4° for the medial ungulae of the forelimbs and 42.50° ± 3.8° for other ungulae of the forelimbs and hindlimbs (standard deviations of the values suggested for the angles should be used as variations between different animals, limbs and ungulae; they should not be used between angles of the same ungula).  相似文献   
53.
The use of pyrolysis products of manures gives positive effects on soil fertility, crop productivity and soil carbon sequestration. However, effects depend on soil characteristics, plant species and the raw material from which the biochar is derived, and some negative effects of biochar have been reported. The objective of this study was to evaluate the effectiveness of poultry manure (PM)‐derived biochar on the growth, and P, N, K, Ca, Mg, Fe, Zn, Cu and Mn concentration of lettuce (Lactuca sativa L.) plant. The treatments as follows: control, 20 g/kg poultry manure (PM), 20 g/kg phosphorus‐enriched poultry manure (PM+P), 10 g/kg Biochar (B), 10 g/kg Biochar+P (B+P). Application of biochar and PM significantly increased lettuce growth, and P‐enriched forms of PM and biochar gave the higher growth. PM has no significant effect on the N concentrations but biochar and, P‐enriched PM and biochar treatments significantly increased N concentrations. Phosphorus concentration of the lettuce leaves significantly increased by PM and biochar treatments. Plant K concentrations were also increased by PM and biochar, and their P‐enriched forms. Leaf Ca and Mg concentrations were lower in Biochar and B+P treatments than that of PM and PM+P treatments. Compared to control and PM treatments, biochar applications reduced Fe, Zn, Mn and Cu concentrations of the lettuce plants. The results of this study indicated that application of biochar to alkaline soil is beneficial for crop growth and N, P and K nutrition, but it certainly reduced Fe, Cu, Zn and Mn nutrition of lettuce.  相似文献   
54.
Mating system parameters and pollen contamination were estimated in an 11-year-old Pinus brutia Ten. clonal seed orchard, located in Antalya, Turkey, with the aid of isozymes. Isozyme analysis was performed on both maternal (megagametophyte) and embryo tissues of seeds collected from the seed orchard and the surrounding natural stand. Fourteen loci encoding nine enzyme systems were assayed. Based on a multilocus estimator, the proportion of viable seeds originating from outcrossing (tˆm) in the seed orchard was found to be 0.947; the remainder (0.053) was due to selfing. We estimated that 85.7% of the orchard seed resulted from pollen contamination by trees in surrounding stands. This may be related to the young age and subsequent low pollen production of the orchard. Only 9% [i.e., 1.0−0.857 (contamination)−0.053 (selfing) = 0.090] of the orchard offspring was due to cross-pollination among clones within the orchard. Due to the high level of pollen contamination, it is estimated that genetic gain in this seed crop is less than 57% of that expected if all offspring resulted from random mating among orchard clones (i.e., no contamination).  相似文献   
55.
Improved fallows involving short-rotation woody and/or other perennial species are increasingly being tried as a means of sustaining crop production in impoverished farming systems of sub-Saharan Africa. The soil-improving potential of two tree species [Gliricidia sepium (gliricidia) and Pteocarpus erinaceus (pterocarpus)] and a shrubby legume Stylosanthes hamata (stylosanthes) was investigated in a four-year study on farmer's field and in a research station in the Koutiala region in southern Mali (12.25° N, 5.42° W; 650 to 850 mm annual, unimodal rainfall; on a Typic Plinthustalf). Two strategies for soil improvement were tested: improved fallow sensu stricto and biomass transfer, the former on-farm and the latter on-station. In the on-farm experiment, maize (Zea mays) yielded best when it followed a two-year fallow of gliricidia alone or in association with stylosanthes. On the research station, maize dry matter production and grain yields during two seasons following the application of ex-situ grown biomass were similar and highest in the stylosanthes- and manure-applied treatments. The biomass decomposition rates of the three species were in the order: gliricidia > stylosanthes > pterocarpus. The treatments did not have any significant effects on the soil fertility parameters that were monitored, possibly because of the short-term nature of the study. The treatments effects on crop yields were, however, significant. Gliricidia + stylosanthes in combination appeared to be particularly promising as short-rotation-fallow species in the region.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   
56.
BACKGROUND: The aim of this study was to investigate the prevalence of hepatitis B virus (HBV) genotypes in Isparta, Southwest of Turkey, as well as the clinical features and transmission route for patients with HBV infections. METHODS: Patients (n = 135) with HBV infection were included in the study. Epidemiological and clinical data were obtained. HBV genotypes were determined with a preS2 epitope ELISA kit. RESULTS: Although the HBV transmission route remained unidentified in 51.1% of the patients, blood contact was determined as the most common probable transmission route (38.5%). One hundred twenty-four (91.8%) of 135 samples, could be genotyped. One hundred fifteen (85.1%) were genotyped as type D/E, six (4.4%) were genotyped as type A, two (1.4%) were genotyped as type C, and one (0.7%) were genotyped as type F. CONCLUSION: Genotype D/E is determined as the predominant HBV genotype circulating in Isparta, Southwest of Turkey. No relationship between genotypes and disease severity and transmission route has been detected.  相似文献   
57.
BACKGROUND: Bifora radians, an annual weed in winter wheat, is distributed mainly in the Mediterranean area, Asia Minor and the Caucasus. It infests winter-sown crops of the Central Anatolia and Middle Black Sea regions of Turkey. Field experiments in heavily B. radians-infested fields were conducted over 3 years in Samsun, Turkey, to determine the response of B. radians to ALS-inhibiting herbicides, because growers had complained of a decrease in herbicide effect. RESULTS: The efficacy of ALS inhibitors on a putatively tolerant population sprayed annually with ALS inhibitors and an adjacent allegedly sensitive population was estimated at the ED50 and ED90 response levels. The recommended rates of herbicides controlled 90% of the weed (ED90) in the sensitive population at the early stage of B. radians development, but not in the tolerant population. The relative potencies (EDx(tolerant)/EDx(sensitive)) of herbicides on the two populations were estimated by assuming years as being random effects. The relative potency was on average about 1.7, irrespective of the EDx levels. CONCLUSION: Although the relative potencies were not large, they were large enough to be noted by growers. In field experiments it would be important to establish tools demonstrating when farmers recognise loss of herbicide efficacy. There has been no indication of evolution of resistant biotypes so far, but continuous spraying favours biotypes with increased levels of tolerance. Copyright © 2011 Society of Chemical Industry  相似文献   
58.
We studied the effect of different food sources, infective juveniles of the entomopathogenic nematodes, Steinernema feltiae and Heterorhabditis bacteriophora (Rhabditida: Steinernematidae, Heterorhabditidae), and tissues from the insect larva, Polyphylla fullo (Coleoptera: Scarabaeidae) or Galleria mellonella (Lepidoptera: Pyralidae), on the development, reproduction and longevity of Sancassania polyphyllae (Acari: Acaridae). We showed that the immature mite stages - protonymph and tritonymph - could develop to the next developmental stage on living or sonicated (i.e., ruptured) S. feltiae or H. bacteriophora. However, the mite larval stage could only develop to the next developmental stage on sonicated infective juveniles of the nematodes. Subsequently, we demonstrated that S. polyphyllae completed development from protonymph to adult on live S. feltiae or H. bacteriophora, whereas all immature stages of S. polyphyllae completed their development from larva to adult on insect tissues. The total developmental period of S. polyphyllae that fed on insect tissues was significantly shorter than those that fed on live infective juveniles. The pre-oviposition, oviposition, and post-oviposition periods and female longevity were not significantly different among the food sources. The total and daily fecundity of S. polyphyllae feeding on P. fullo and G. mellonella was significantly higher than those feeding on S. feltiae and H. bacteriophora, although there was no significant difference observed between P. fullo and G. mellonella or between S. feltiae and H. bacteriophora. The net reproductive rate (R0) was highest (588.3♀/♀) when S. polyphyllae fed on P. fullo. The longest mean generation time (T0) occurred on H. bacteriophora (12.6 days) and the shortest occurred on P. fullo (10.5 days). S. polyphyllae, which fed on P. fullo (rm=0.61) and G. mellonella (rm=0.55) had the highest intrinsic rate of increase (rm) compared to mites that fed on S .feltiae (rm=0.45) and H. bacteriophora (rm=0.41).  相似文献   
59.
This study was conducted to determine the pathological changes in testes and epididymides and plasma testosterone levels of adult roosters during experimentally induced aflatoxicosis. In the study, 24 months of age, 32 Babcock breeder males were used, and they were divided into four groups each containing 8 animals. The groups were designed as follows; group 1: Control, no aflatoxin (AF), group 2: 5 ppm (parts per million) total aflatoxin (AF; B1, B2, G1, G2), group 3: 10 ppm AF and group 4: 20 ppm AF in the diet, and the birds were fed for 8 weeks. Grossly, it was seen that the testes of all AF-treatment groups birds were significantly (P < 0.001) atrophied when compared with those of control birds. Histopathologically, there was no spermatogenesis in the testes of 4, 5 and 6 cocks fed on a diet containing AF 5, 10 and 20 ppm, respectively. Furthermore, abnormal spermatozoa were observed in some of AF-treatment groups (in 2 cases in each of 5 and 10 ppm AF-treated groups, and in one case in 20 ppm AF-treated group). There were also mononuclear cell infiltration and/or focal lymphoid cell accumulation in the intertubular areas of the testes and epididymides in all AF-treatment groups. In conclusion, it has been shown that AF might totally or partially (dose related) suppress spermatogenesis, cause abnormality in spermatozoa and atrophy in testes. Furthermore, there was degeneration and desquamation in the epithelium and decrease in the size and thickness of the germinative layer of the seminiferous tubules, and lowered plasma testosterone levels in adult roosters.  相似文献   
60.
A total of 35 Escherichia coli isolates obtained from necropsy materials of hens with septicemia in the Konya region of Turkey were examined for hemagglutination (HA), cell-surface hydrophobicity, enterotoxigenicity, and drug resistance. HA tests were performed on live cultures with human (group A), bovine, avian (chicken), and guinea pig erythrocytes with and without mannose. Nine HA patterns were observed. Of the 35 isolates, 62.8% exhibited mannose sensitive hemagglutination (MSHA), 8.6% exhibited mannose resistant hemagglutination (MRHA), and 28.6% did not hemagglutinate. Of the isolates, 85.7% were hydrophobic by a salt aggregation test (SAT). Only three isolates were enterotoxigenic by a suckling mouse assay. The majority of the isolates were resistant to chloramphenicol, tetracycline, streptomycin, ampicillin, erythromycin, and trimethoprim + sulfamethoxazole but were highly sensitive to gentamicin and nalidixic acid.  相似文献   
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