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11.
In this study, raw cow milk samples were collected from milk churns at 40 traditional and semi-industrial cattle farms located in Babol (Northern Iran) in winter 2006. In total, 120 raw milk samples were tested for Aflatoxin M1 (AFM1) contamination by competitive ELISA. In 68 out of 120 samples (56.7%) the presence of AFM1 was detected by concentration ranging from 50 to 352.3 ng L(-1). Fifty two samples (43.3%) contained AFM1 at levels of 4-50 ng L(-1) (The AFM1 contamination levels were between 4-352.3 ng L(-1) by the average of 102.73 ng L(-1)). In general, 56.7% of samples were beyond the limit of European community regulations (50 ng L(-1)). In other words, the AFM1 contamination levels in raw milk were more than twice over standard levels. The AFM1 contamination levels, (> 50 ng L(-1)), in January, February and March were 40, 65 and 65%, respectively. Estimation of contamination of AFB1 using AFM1 in feed stuff showed that it was about 0.25 to 22 microg kg(-1) holding the average of 46.7%, being higher than European community limit (5 microg kg(-1)).  相似文献   
12.
A karyotype study was performed on 15 populations of Eremostachys laciniata Bunge from Iran in order to quantify the extent of cytological variation for use in breeding programmes. Ten mitotic root tip cells at the metaphase stage were prepared from each population by the squash method. The chromosomes of suitable mitotic cells were counted and various parameters, including long and short arm lengths, chromosome lengths, total length of the haploid chromosome complement, arm ratios, and the centromeric index, were measured. All 15 populations were diploid with 2n = 2x = 22 and were differentiated by their karyotypic parameters. All 15 E. laciniata populations occupied Class 1A of Stebbins’ karyotype classification, indicating the presence of a primitive symmetrical karyotype. The size of the mitotic chromosomes was medium, and mean chromosome lengths ranged from 3.84 to 4.77 μm. The shortest chromosome lengths were observed in the Ajabshir population and the longest in the Heydarabad population. The Heydarabad population also had the longest total chromosome length and the Ajabshir population had the shortest total chromosome length. The centromeric indices of the chromosome complements varied from 39.3% to 43.7%. Metacentric chromosomes were the most common in all populations, whereas submetacentric chromosomes were rare. The A1 index varied from 0.215 (Areshtanab) to 0.337 (Til). The A2 index ranged from 0.116 (Til) to 0.143 (Kaleybar), and the karyotype asymmetry index varied between 0.051 and 0.097. The results of a principal component analysis (PCA) showed that the main elements of the first three main principal components accounted for 97% of the total variance. Cluster analysis by Ward’s method indicated that all 15 populations could be classified into three clusters. Finally, the results of the karyotypic parameters showed that the Til, Heydarabad, and Marand populations had higher levels of karyotypic heterogeneity and may be useful when developing breeding programmes.  相似文献   
13.
Five severe cases of psittacosis in individuals associated with duck farms were notified in France between January and March 2006. Diagnostic examination included serology and/or molecular detection by PCR from respiratory samples. As a consequence, we investigated all duck flocks (n=11) that were housed in the three farms where human infections occurred. While serology by complement fixation test was negative for all samples, cloacal and/or tracheal chlamydial excretion was detected by PCR in all three units. Notably, one duck flock was tested strongly positive in 2 of the 3 affected farms, and Chlamydophila (C.) psittaci strains were isolated from cloacal and/or tracheal swab samples from both farms. Human samples and duck isolates exhibited the same PCR-RFLP restriction pattern, which appeared to be an intermediate between genotypes A and B. Analysis of ompA gene sequences and comparison to those of the type strains showed that the isolates could not be strictly assigned to any of the generally accepted genotypes of C. psittaci. Further analysis by MLVA of the PCR-positive human samples revealed two distinct patterns, which were related to previously isolated C. psittaci duck strains.  相似文献   
14.
Journal of Plant Diseases and Protection - Black spot disease is the most common diseases of landscape roses and is caused by Diplocarpon rosae Wolf. In Rosa multiflora, the screening of black...  相似文献   
15.
In order to compare of different methods and identify the optimum condition for tomato seed extraction, factorial experiments with 3 replications was conducted. In the first experiment, pulp of two tomato cultivars (Faraon, Dominator) were fermented at two temperatures (25, 35 degrees C) and six periods (24, 48, 72, 96, 120, 144 h). The germination of seeds in laboratory as well as seedling emergence and preliminary growth in greenhouse were studied and measured. The results showed that effect of cultivar on traits (except of seedling emergence) was significant. Also the effect of temperature of fermentation, duration of fermentation and also interaction effects of them on seed germination were significant. Totally seed quality decreased with increasing temperature and duration of fermentation and the fermentation duration from 24 to 48 h at temperature 25 degrees C, is recommended. In the second experiment, tomato seeds were extracted by HCL (pH was arranged to 1, 2, 3 for 10, 20, 30 min), H2SO4 (pH was arranged to 1, 2, for 15, 30 min), Sodium carbonate (5, 10% for 24 and 48 h) and fermentation. Percentage germination, germination rate, length of radicle and length of plumule were used for seed quality assessment. The results showed that interaction effect between pH and duration of HCL treatments was significant for seed germination (percentage and rate) and there was an interaction effect between concentration and duration for germination rate in alkali treatments. Different extraction methods had not detrimental effect on percentage germination, but acid treatments produce very bright clean seeds in compare to other treatments.  相似文献   
16.
17.
The interaction between the sequence of feeding of hay and concentrate and the hydrothermal processing of barley in alleviating concentrate effects on intake, and hindgut fermentation in horses was tested. Six Arabian mares (4–10 years of age, 410 ± 35 kg body weight) were used to evaluate the effects of feeding sequence (FS) and type of barley (TB) on intake, and faecal volatile fatty acids (VFA), activities of α‐amylase (AA: EC 3.2.1.1), carboxymethyl cellulase (CMCase: EC 3.2.1.4), microcrystalline cellulase (MCCase: EC 3.2.1.91) and general filter paper degrading activity (FPD). Mares were offered a ration of air‐dried alfalfa and concentrate (70:30 as‐fed) in four subsequent periods of 14 days including 8 days of adaptation and 6 days of sampling. In each period and each meal, mares received concentrate either 30 min after (HC) or 30 min before (CH) alfalfa hay. Barley was either milled or boiled in water. Rectal samples were grabbed directly from rectum once per period. Mares subjected to CH had higher dry matter intakes than mares under HC regime. The acetate:propionate ratio (A:P ratio) in rectal content was higher with CH than HC. The AA activity was higher under CH than under HC. Mares fed boiled barley had lower rectal concentrations of VFA and propionate and a higher A:P ratio than mares fed milled barley. Furthermore, the rectal content showed a higher MCCase activity but a lower AA activity when mares were fed boiled compared with milled barley. Interactions between FS and TB were observed with respect to CMCase activity, and concentrations of propionate and valerate. In conclusion, the present results suggest that both, feeding concentrate before hay and boiling the barley, might improve the hindgut environment in Arabian mares, and that the two measures were mostly additive and sometimes even synergistic.  相似文献   
18.
A laboratory study was conducted in order to explain successive extractions of reserved potassium by using concentrated HCI under reflux for 13 surface and sub-surface soil samples representing three chosen pedons of soil series (472 ECC Bashika, 463 EKC Rabeaa and 461 ECC Talafar) locations of Nineveh Province in Northern of Iraq. The aim is to investigate role of clay minerals on release of reserved potassium from soils. Results showed that dominated clay minerals were (smectite 〉 illite 〉 kaolinite 〉 chlorite) for both 472 ECC and 461 ECC soil series and were (illite 〉 smectite 〉 kaolinite 〉 chlorite) for 463 EKC soil series. Also results appeared that exchangeable K+ released values were 2,483-4,575 mg/kg at 461 ECC and 463 EKC soil series, respectively; non-exchangeable phase ranged from 752-1,390 mg/kg at 461 ECC and 472 ECC soil series, respectively. Soil fertility was evaluated according to its K+ mica release referring for high K+ release content with range between 3,324-5,516 mg/kg at 461 ECC and 463 EKC soil series, but rate ofK~ released was very law according to parabolic diffusion me,del with range from 195-359 mg/kg at latter soil series respectively. Results reflect effect of clay minerals on potassium release as amount and rates in arid and semi-arid regions. It can be concluded the study soils have a high amount of potassium content with low rate release of it, in turn these soil need particular management.  相似文献   
19.
Considering increasing rate of Iran population and consumption of wood panels, the authors investigated the per capita consumption of wood panels during the years from 1997 to 2007. The exponential smoothing method was used to obtain a per capita consumption pattern of wood panels in Iran for estimating demand of wood panels by the year of 2012. Results show that the consumption of particleboard, fiberboard, and medium density fiberboard in Iran will increase by 33%, 72% and 107 %, respectively, by the year of 2012; however, the consumption of plywood will increase only by 7% by 2012. The deficient amount of wood panels in Iran is estimated over 1400000 m3. The results of this study provide the technique reference for planners of wood panel industries in Iran in capital investment decisions.  相似文献   
20.
This study reports on the spermatological properties, and on the development of a protocol for refrigerator storage (4°C) of Labeo calbasu (Hamilton, 1822) sperm for artificial breeding. Volume, motility, concentration and pH of the freshly collected sperm were 2.21 ± 0.53 (μL g?1 of fish weight) (mean ± SD), 95 ± 1 (%), 1.93 ± 0.44 × 109 (cells mL?1) and 7.56 ± 0.17 respectively. Sperm activation was evaluated at different osmolalities of NaCl solution, and motility ceased completely when osmolality of the extender was ≥287 mOsmol kg?1. Sperm retained motility for 24, 72 and 108 h, after refrigerator storage when sperm were undiluted, suspended in Alsever's solution and suspended in Alsever's solution containing 5% methanol respectively. Fertilization rate of fresh eggs with sperm stored at 4°C in Alsever's solution and Alsever's solution containing 5% methanol was 77% and 60% with a hatching rate of 60% and 43% respectively. The fertilization and hatching success of the stored sperm suggests potential to use refrigeration for transporting genetic material to hatcheries for artificial breeding of L. calbasu in Bangladesh.  相似文献   
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