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61.
Tabari Masoud; Fayaz Payam; Espahbodi Kambiz; Staelens Jeroen; Nachtergale Lieven 《Forestry》2005,78(4):443-450
The response of nursery seedlings and wildings of oriental beech(Fagus orientalis Lipsky) to canopy gap size was studied ina climax beech forest in northern Iran with respect to seedlingsurvival, shoot growth and vitality. These parameters were followedfor 2 years after planting in gaps of 50, 200 and 600 m2, aswell as in the open field. Foliage coloration was used as acriterion for vitality. The survival rate of nursery seedlingsand wildings dropped rapidly with increasing gap size from 84per cent in 50-m2 canopy openings to 相似文献
62.
Ansari-Lari M Haghkhah M Bahramy A Novin Baheran AM 《Tropical animal health and production》2009,41(4):553-557
A cross-sectional study was conducted from March to August 2006 in dairy herds in Fars province, southern Iran to determine
the herd-level risk factors for infection with Mycobacterium avium subspecies paratuberculosis (MAP). Statistical analysis using multivariable logistic regression showed that contamination of udders of periparturient
cows with manure (OR = 6.4, P = 0.02) and history of having suspected cases of Johne's disease in the herd (OR = 6.7, P = 0.04)
were significantly associated with the herd infection status. No relationship between breed, herd size and other management
practices with the infection status of the herd were found in this study. Implementing high sanitary measures in the farm,
particularly with respect to manure handling and cleaning could be considered as one of the important aspects in controlling
disease in the region as well as in the future educational effort. 相似文献
63.
Nazifi S Ansari-Lari M Asadi-Fardaqi J Rezaei M 《Veterinary journal (London, England : 1997)》2009,182(2):315-319
Acute phase proteins (APPs) such as serum amyloid A (SAA), haptoglobin (Hp), and plasma fibrinogen (Fb) are diagnostic and prognostic biomarkers. This study determined the pattern of SAA in traumatic reticuloperitonitis (TRP) in cows, and compared the findings with Hp, and plasma Fb concentrations in the differential diagnosis of TRP using receiver operating characteristic (ROC) analysis. Blood samples were collected from 89 cows: 53 cases of TRP, 16 animals with other internal disorders and 20 healthy controls.SAA and Hp had a similar pattern and magnitude of changes in TRP. Using the ROC method, the optimal cut-off for the diagnosis of TRP was 68 μg/mL for SAA and 0.74 g/L for Hp, with 100% sensitivity and 86.1% specificity; either of these parameters may therefore be used as a sensitive and relatively specific tool for the differential diagnosis of TRP in cattle. The diagnostic accuracy of plasma Fb was significantly lower than either SAA or Hp (P < 0.01). The combined use of these APPs (whilst aware of their conditional interdependence) may not provide any additional diagnostic information than can be obtained using either SAA or Hp alone. 相似文献
64.
Objective To observe the effect of topical 1% tropicamide on equine tear production as measured by Schirmer I tear test.
Materials and methods Fourteen adult horses received one drop of 1% tropicamide ophthalmic solution in one eye and the opposite eye served as the control. The tear production in both eyes was tested at 1, 2, 4, 6, and 24 h after 1% tropicamide administration.
Results Measurements made 1 h after treatment revealed a significant reduction in Schirmer tear test values in tropicamide treated eyes ( P = 0.002). The observed decrease in tear production was maintained up to 4 h after treatment ( P = 0.002). Although tropicamide-induced decrease in STT values was observed in the treated eyes, the contralateral eyes did not show significant changes in Schirmer tear test results.
Conclusion Single dose of topical 1% tropicamide resulted in statistically significant reduction in Schirmer tear test values in clinically normal horses. 相似文献
Materials and methods Fourteen adult horses received one drop of 1% tropicamide ophthalmic solution in one eye and the opposite eye served as the control. The tear production in both eyes was tested at 1, 2, 4, 6, and 24 h after 1% tropicamide administration.
Results Measurements made 1 h after treatment revealed a significant reduction in Schirmer tear test values in tropicamide treated eyes ( P = 0.002). The observed decrease in tear production was maintained up to 4 h after treatment ( P = 0.002). Although tropicamide-induced decrease in STT values was observed in the treated eyes, the contralateral eyes did not show significant changes in Schirmer tear test results.
Conclusion Single dose of topical 1% tropicamide resulted in statistically significant reduction in Schirmer tear test values in clinically normal horses. 相似文献
65.
S Saifzadeh R Hobbenaghi S Asri‐Rezaei F Shokouhi SJ B Dalir‐Naghadeh M Rohi S 《Reproduction in domestic animals》2008,43(6):678-684
A novel technique [Section‐Ligation‐Release (SLR)] was evaluated for castration in the horse. Clinical traits, serum testosterone concentrations after challenge with human chorionic gonadotrophin (hCG), and histopathological changes of the testicular tissue were assessed. Five stallions, aged 24–48 months, were castrated using SLR technique under general anaesthesia. Both spermatic cords in each stallion were exposed at the scrotal neck by two 5‐cm long incisions, followed by sharp dissection through the parietal vaginal tunic. Both vascular and non‐vascular structures in the cords were triple clamped, transected and ligated. Both testes were left in situ. Serum testosterone concentrations were measured pre‐operatively and at 2 months after castration following IV administration of 1 × 104 IU of hCG. Both testes from each castrate were collected at 2 months for histopathologic examination. SLR castration was successfully achieved. Moderated scrotal and preputial swelling was the only experienced short‐term complication. Serum testosterone concentrations were significantly lower than basal pre‐operative levels at 2 months after castration, and did not respond to hCG. On histopathology, hyalinization of the seminiferous tubules and loss of testicular interstitial tissue were indicative of complete avascular necrosis. This novel primary closure castration technique of stallion is a simple practical method, with minimal post‐operative complications; and could be safely advocated as an alternative to the traditional castration techniques allowing for second intention healing of scrotal wounds. 相似文献
66.
The nutritional effect of Isochrysis galbana and Chaetoceros muelleri cultured with different seaweed extracts on the larval development,growth and survival of the marine shrimp,Penaeus indicus
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Kiuomars Rohani‐Ghadikolaei Eisa Abdolalian Fouroghi Hojatollah Gharibnia Masoud Wing‐Keong Ng 《Aquaculture Research》2015,46(6):1444-1454
The microalgae Isochrysis galbana and Chaetoceros muelleri were cultured with seaweed extract (SWE) from six different seaweeds and each SWE was used either as a supplement or as an alternative media to conventional f/2 medium. Microalgae cultured with only the f/2 media acted as the control treatment. I. galbana and C. muelleri were then fed to Penaeus indicus larvae, either singly or in combination, for 8 days to evaluate its nutritional quality. Shrimp larvae fed on microalgae cultured in f/2 media supplemented with SWE from Ulva lactuca or Enteromorpha intestinalis moulted faster (P < 0.05) to the second mysis stage compared with the control. Survival, total length and growth rates were better in shrimp larvae fed on microalgae previously cultured in media supplemented with SWE. In general, shrimp larvae fed microalgae cultured entirely in SWE performed equally well compared with the control. Shrimp larvae fed on mixed microalgae (I. galbana + C. muelleri) showed significantly better growth, survival and development compared with larvae on either single microalgal diet. It was concluded that microalgae cultured with SWE could be used as a low‐cost alternative media in producing live food for the hatchery production of shrimp larvae. 相似文献
67.
D. Rapp A. Richaume P. Jame P. Rigou H. Rezaei P. Alcouffe J.‐P. Chapel H. Quiquampoix P. Potier 《European Journal of Soil Science》2011,62(4):607-616
Soils contaminated by prions, the infectious agents responsible for transmissible spongiform encephalopathy diseases, remain infectious to grazing animals for many years. In this study, the ability of enzymes produced by soil microbes to degrade a recombinant prion protein (recPrP) was investigated in a loamy soil. A 15N‐labelled recPrP was added to soil in which microbial biomass and soil proteolytic activity had been increased by either simultaneous or prior amendment with lamb brain, and distribution of 15N among soil solid particles, soluble molecules and bacterial biomass was determined. After 1 day the proportions of recovered recPrP‐N associated with microbial biomass and soluble molecules were 6–9 and 15–19%, respectively, which is consistent with the hypothesis of degradation. A greater incorporation of 15N‐derived β‐sheeted recPrP into the microbial biomass pool occurred when the soil proteolytic activity was pre‐stimulated by a lamb brain amendment, suggesting that the recPrP degradation in soil is mediated by the activity level of proteolytic enzymes produced by the microbial biomass. The majority (35–87%) of the recovered recPrP‐N was associated with the soil particles. An observed partial degradation of recPrP deposited on a mica surface by soil soluble enzymes indicated a sorption‐related resistance to proteolysis. In conclusion, integration of the stimulation and turnover of the soil microbial component, after an input of a large amount of animal organic matter with the sorption properties of prion protein, is required to model and predict prion survivability, transformation and transmissibility in soil. 相似文献
68.
Shahsavari Shiva Noormohammadi Zahra Sheidai Masoud Farahani Farah Vazifeshenas Mohammad Rreza 《Genetic Resources and Crop Evolution》2021,68(7):2943-2957
Genetic Resources and Crop Evolution - The pomegranate fruit is one of the most important horticultural products due to the presence of polyphenols, anti-oxidant and anti-fungal compounds. In the... 相似文献
69.
Mohammad Amin Miri Jebrail Movaffagh Mohammad B. Habibi Najafi Masoud Najaf Najafi Behrouz Ghorani Arash Koocheki 《Fibers and Polymers》2016,17(5):769-777
Biodegradable edible sub-micron electrospun zein fibers were prepared using acetic acid as solvent. The solution concentration at three levels: 22, 26 and 30 w/v %, the electrospinning voltage at three levels: 10, 20 and 30 kV, the solution flow rate at three levels: 4, 8 and 12 ml/h and the distance between needle tip and collector at three levels: 10, 15 and 20 cm were studied. Central composite design (CCD) was utilized to modeling the effect of electrospinning parameters of zein solution on average fiber diameters and the data were analyzed using response surface methodology (RSM). Coefficient of determination, R2, of fitted regression model was higher than 0.9 for response. The analysis of variance table showed that the lack of fit was not significant for response surface model at 95 %. Therefore, the model for response variable was highly adequate. Results also indicated that the solution concentration had significant influence (P<0.0001) on morphology and diameter of fibers. By increasing the solution concentration, uniform and bead-free fibers were obtained. As the solution concentration was increased, the average fiber diameters were also increased. Furthermore, the electrospinning voltage had significant effect (P<0.0001) on average fiber diameters. By increasing the electrospinning voltage, the average fiber diameters increased. The solution flow rate and the distance between needle tip and collector had no significant influence on the average fiber diameters. According to model optimization, the minimum average fiber diameter of electrospun zein fiber is given by following conditions: 24 w/v % zein concentration, 10 kV of the applied voltage, 10 cm of needle tip to collector distance, and 4 ml/h of solution flow rate. 相似文献
70.
Carole E.R. Pitcairn Ian D. Leith David Fowler Ken J. Hargreaves Masoud Moghaddam Valerie H. Kennedy Lennart Granat 《Water, air, and soil pollution》2001,130(1-4):1037-1042
The foliar N content of bryophytes and Calluna vulgaris (L.) has been shown to be an indicator of atmospheric N deposition in the UK at a regional scale (1000km) and more recently on a smaller scale in the vicinity of intensive livestock farms. This work extends the geographical scale of the relationship between foliar N concentration of Calluna vulgaris and other ericaceous shrubs and N deposition with 2 measurement transects, one extending from northern Finland to southern Norway (2000 km) and the other extending from central Sweden to Stockholm, south east Sweden (330 km). Included in the second transect is a region of complex terrain in the Transtrand uplands, where the variation in N deposition with altitude and canopy cover was quantified using 210Pb inventories in organic soil. The relationship between foliar N (FN) and N deposition was shown to increase linearly with N deposition (ND) over the range 0.8% N to 1.4% N according to FN = 0.040ND + 0.793 (r2 = 0.70). The data are entirely consistent with earlier studies which together provide a valuable indicator of critical loads exceedance, the threshold value being approximately 1.5% N, which is equivalent to a N deposition of 20 kg N ha?1 y?1. 相似文献