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51.
Antibiogram and heavy metal resistance patterns of pathogenic bacteria isolated from moribund cage cultured silver catfish (Pangasius sutchi) and red hybrid tilapia (Tilapia sp.) from Sungai Manir, Terengganu, Malaysia were studied and characterized. Sungai Manir is one of the famous rivers in Terengganu for its wide variety of cage cultured freshwater fish. However, to date, the baseline information of antibiogram and heavy metal resistance patterns of the pathogenic bacteria attacking the freshwater fish cultured in Sungai Manir is still lacking. Therefore, this study was carried out, which may be useful for fish farmers as a guideline for fish prophylactic and treatment purposes. Furthermore, present studies also provide information on the safety level of consuming freshwater fish produced from Sungai Manir. In the present study, bacteria were isolated from 100 fish of each moribund silver catfish and red hybrid tilapia using seven media including tryptic soy agar (TSA), Mac Conkey, thiosulphate citrate bile salt (TCBS), eosin methylene blue (EMB), glutamate starch pseudomonas (GSP), xylose lysine deoxycholate (XLD) and Baird Parker media. Identification of bacteria was carried out using conventional biochemical tests and confirmed by commercial bacterial identification kit. Antibiogram of the bacterial isolates against 18 antibiotics; oxolinic acid (2 μg), ampicillin (10 μg), erythromycin (15 μg), furazolidone (15 μg), lincomycin (15 μg), oleandomycin (15 μg), amoxicillin (25 μg), colistin sulphate (25 μg), sulphamethoxazole (25 μg), chloramphenicol (30 μg), doxycycline (30 μg), florfenicol (30 μg), flumequine (30 μg), kanamycin (30 μg), nalidixic acid (30 μg), tetracycline (30 μg), nitrofurantoin (50 μg) and spiramycin (100 μg) was carried out using disk diffusion method, whereas heavy metal resistance patterns (Hg2+, Cd2+, Cr6 + and Cu2+) of the bacterial isolates was determined through twofold agar dilution method. The results showed that the percentage of sensitivity case of the 120 bacterial isolates to the tested antibiotics was 62.7%. This was followed by resistance (26.9%) and intermediary sensitive (10.4%) cases. In terms of the heavy metal resistance patterns, all bacterial isolates were resistant to Hg2+ and Cr6 +. However, only 27.8% and 16.7% of the bacterial isolates were sensitive to Cu2+ and Cd2+, respectively. The multiple antibiotic resistance (MAR) indices indicated that the cage cultured silver catfish and red hybrid tilapia were under high exposure to the tested antibiotic. Overall, the results of the present studies showed that Sungai Manir may be polluted with heavy metal and antibiotic residues.  相似文献   
52.
Six healthy camels were treated with the tranquilizers propionyl promazine (Combelen), xylazine (Rompun), acepromazine (Calmivet) or chlorpromazine (Largactil) at single intramuscular doses of 0.5, 0.25, 0.1, or 3 mg/kg, respectively; and the onset, duration and degree of sedation produced by each drug was assessed for six hours. The effect of the treatments on some haematological and biochemical parameters was also studied. The onset and duration of action of the tranquilizers were 10 min and 2.1 +/- 0.5 h for propionyl promazine, 4 min and 3.1 +/- 0.4 h for xylazine, 5 min and 2.3 +/- 0.5 h for acepromazine, 7 min and 2.5 +/- 0.4 h for chlorpromazine, respectively. It was observed that 5-10 min after the administration of the four drugs, camels showed slight irritability, dropping of the lower lips and scratching of the nostrils against objects. During the first hour after medication camels showed frequent urination, defaecation and lacrimation. Xylazine seemed to be superior to the other three drugs in producing sedation. No significant effect on the rectal temperature or the respiratory rates of treated camels was seen after the administration of the four drugs. There were consistent, but statistically insignificant decreases (about 10 p. 100) in the haemoglobin concentration and erythrocyte counts of camels one hour after treatment with the tranquilizers. The four drugs, particularly xylazine and propionyl promazine produced significant hyperglycaemia, but did not alter significantly the plasma concentration of urea or activity of aspartate aminotransferase.  相似文献   
53.
The aims of this study were to determine the concentrations of the progesterone, oestradiol‐17‐β, vitamin A, C and β‐carotene in plasma and cyst fluid and to relate these values with cystic diameter and membrane thickness of Holstein cattle with ovarian luteal cyst. 1650 Holstein cows were examined for the presence of the ovarian cyst and luteal and follicular cystic ovaries were obtained following slaughtering in personal slaughterhouse in Konya‐Turkey. 15 Luteal and 15 follicular cystic ovaries were distinguished by rectal palpation and by post mortem ultrasonographic examination. Plasma and cyst fluid, hormone and vitamin analyses were carried out by EIA method and spectrophotometric measurement respectively. Although there was no relationship between β‐carotene and vitamin A in plasma and cyst fluid of both cyst type and hormone concentrations, the vitamin C concentration of cyst fluid was found significantly higher in luteal cyst than in follicular cyst. Moreover, there is a positive correlation among values of the vitamin C concentrations of cyst fluid and cystic membrane thickness, plasma and the cyst fluid progesterone concentrations, but there is a negative correlation among the vitamin C concentrations of cystic fluid and oestradiol 17β levels of plasma and cyst fluid. In conclusion, vitamin C concentration of cyst fluid supported ultrasonographic and endocrinologic findings. Also, it can be postulated that vitamin C is probably effective on progesterone synthesis in the luteal tissue of cyst.  相似文献   
54.
Waterlogging is a major constraint of faba bean (Vicia faba L.) production in the highland vertisols of Ethiopia. Genotypes are currently evaluated under both the drained conditions of Broad Bed and Furrow(BBF) and the undrained flatbeds. The objective of this research was to determine if selection of genotypes under BBF is efficient for identification of genotypes for the flatbed conditions. Yields under the flatbed conditions were lower by 20–50% (38% on average) than yields under the BBF. Genetic variation, heritability and predicted genetic gains for grain yield due to direct selection were also lower under the flatbeds than they are under the BBF. There were good levels of genetic correlation (r = 0.20–0.75 or0.45 on average) between yield performances under BBF and flatbeds, indicating that selection under BBF may identify good genotypes for flatbeds and vice versa. There was also high association (r =0.91) between relative yield reduction under flatbeds and the ratio of the predicted genetic gains from indirect selection under BBF to the predicted genetic gains from direct selection under flat beds. This indicates that indirect selection under BBF may be useful to identify better genotypes for flatbed conditions, but the relative efficiency of indirect selection was lower than direct selection under flatbeds themselves. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
55.
The genetic nature of bacterial wilt resistance in tomato was studied in two crosses based on the number of days of survival (quantitative) in the field before the appearance of wilt symptoms. Significant differences were observed between generation means in both crosses (LA 1421 × Cascade and LA 1421 × Caraibo). This study indicates that resistance identified in Lycopersicon esculentum var. cerasiforme LA 1421 may be different from that derived from L. pimpinellifolium. However, the genetic mechanism seems to be complex with a duplicate form of epistasis. Results suggest that selection for resistance from crosses between LA 1421 and Cascade should preferably be delayed until a high level of fixation of genes is attained. The variation observed in the F2 and BC2 progeny of the Caraibo cross, suggested that genetic combination between the two resistance sources can lead to higher levels of resistance. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
56.
57.
Seed oils of 11 samples of Capparis ovata and Capparis spinosa from different locations in Turkey were characterized with regard to the composition of fatty acids, tocopherols, and sterols as well as the content of glucosinolates. The oil content of the seeds ranged from 27.3 to 37.6 g/100 g (C. spinosa) and from 14.6 to 38.0 g/100 g (C. ovata). The dominating fatty acid of both species was linoleic acid, which accounted for 26.9-55.3% in C. ovata seed oils and for 24.6-50.5% in C. spinosa seed oils. Oleic acid and its isomer, vaccenic acid, were both found in the seed oils in concentrations between 10 and 30%, respectively. The seed oils of both species were rich in tocopherols with the following composition: gamma-tocopherol, 124.3-1944.9 mg/100 g; delta-tocopherol, 2.7-269.5 mg/100 g; and alpha-tocopherol, 0.6-13.8 mg/100 g. The concentration of total sterols ranged from 4875.5 to 12189.1 mg/kg (C. ovata) and from 4961.8 to 10009.1 mg/kg (C. spinosa), respectively. In addition to sitosterol, which amounted to approximately 60% of the total amount of sterols, campesterol and stigmasterol accounted for 16 and 10% of the total sterols, respectively. The seed oils showed remarkably high contents of Delta5-avenasterol (between 138.8 and 599.4 mg/kg). The total content of glucosinolates of C. ovata and C. spinosa samples was determined as 34.5-84.6 micromol/g for C. ovata and 42.6-88.9 micromol/g for C. spinosa, respectively, on a dry weight basis, with >95% as glucocapperin.  相似文献   
58.
Fusarium head blight is one of the most serious cereal diseases of the world. Epidemics of Fusarium head blight can lead to a decline in grain quality and yield. In addition, grains often become contaminated with mycotoxins, which are harmful to humans and animals. In a field survey of winter wheat in Switzerland, Fusarium graminearum proved to be the most prevalent species responsible for head blight and deoxynivalenol the most common mycotoxin. To elucidate and quantify single or combined effects of cropping factors on F. graminearum infestation and to reduce the risk of mycotoxin contamination of wheat under conservation tillage, we developed the decision support system FusaProg. Our model takes into account the effects of cropping factors, previous crops, soil and straw management, as well as the F. graminearum susceptibility of the planted variety. These factors are used as driving variables and are combined with the prevailing weather conditions and growth stage in order to predict the deoxynivalenol content of a specific wheat plot before harvest. To use FusaProg as a threshold‐based tool to control F. graminearum with optimized timing of fungicide applications, forecasts of deoxynivalenol contents are conducted during the flowering period. FusaProg is an Internet‐based decision support system which not only provides information about the local and regional F. graminearum infection risks; it also forecasts plot‐specific deoxynivalenol contamination of winter wheat. In 2006, the system was evaluated by Swiss cantonal plant protection officers, and in 2007, the system will be made available to Swiss wheat producers.  相似文献   
59.
This study was carried out to examine the relationship between the corpus luteum (CL) weight, CL and follicle diameters and progesterone, β‐carotene and vitamin A levels in reproductive organs of cattle obtained from the slaughterhouse. The β‐carotene and vitamin A levels were determined in plasma, CL and follicular fluid (FF) using a spectrophotometric method at different stages of the oestrous cycle (n=40) and at 3–6 months of pregnancy (n=10). The diameters of the CL and follicle were measured using ultrasonography. Plasma progesterone concentrations were determined by an enzyme immunoassay method. The vitamin A levels of the plasma, CL and FF were not related to each other. The highest plasma vitamin A levels were observed in the proestrus and oestrus, at which periods follicular activity dominates. The vitamin A levels in the CL and FF were negatively related to the weight and diameter of the CL and the diameter of follicle, respectively. In contrast to vitamin A, β‐carotene concentrations of plasma, CL and FF were significantly correlated with each other. The highest β‐carotene levels in the plasma, CL and FF were found during pregnancy when there is maximal luteal function, and the β‐carotene level of the CL was significantly correlated with the weight and diameter of CL. Furthermore, the intrafollicular β‐carotene level was negatively correlated with the follicle diameter. There was a positive correlation between plasma progesterone level and the weight and diameter of the CL, but a negative correlation between plasma progesterone level and follicle diameter. Moreover, plasma, FF and CL β‐carotene levels were positively correlated with plasma progesterone levels. This study revealed that β‐carotene levels in the plasma, CL and FF were influenced by the stage of the oestrous cycle or the pregnancy and were related to bovine luteal function without depending on vitamin A.  相似文献   
60.
ABSTRACT: Substantial debate exists on whether the immune response between sheep resistant and susceptible to gastrointestinal nematodes can be differentiated into a Th1 and Th2 phenotype. The present study addresses the hypothesis that variation in resistance to Teladorsagia circumcincta between DRB1*1101 (associated with reduced faecal egg count and worm burden) carriers and non-carriers is due to a differential interplay in the expression of Th1/Th2 and regulatory T (Treg) related cytokine genes. Lambs from each genotype were either slaughtered at day 0 (un-infected control) or infected with 3 × 104 Teladorsagia circumcincta L3 and slaughtered at 3, 7, 21, and 35 days later. Lambs carrying the DRB1*1101 allele had a significantly lower worm burden (P < 0.05) compared to the non-carriers. Abomasal mucosal cytokine gene expression was evaluated by quantitative real-time PCR and comparison made for time and genotype effects. The response generated varied through the course of infection and was affected by genotype. DRB1*1101 carriers had an up-regulated expression of the Th1-related cytokine genes (IL-1β, TNFα, and IFN-γ) at day 3, but this was replaced by an up-regulated expression of Th2-related cytokine genes (IL-10 and IL-13) and Treg-related cytokine genes (IL-2RA-CD25, TGFα, TGFβ, Arg2, MIF and FOXP3) by day 7. Conversely, in the non-carriers these changes in gene expression were delayed until days 7 and 21 post infection (pi), respectively. It is concluded that resistance to Teladorsagia circumcincta in animals carrying the DRB1*1101 allele is influenced by an earlier interplay between Th1, Th2 and T regulatory immune response genes.  相似文献   
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