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41.
The effect of pH and calcium on copper bioavailability to the springtail Folsomia candida was determined by assessing uptake kinetics upon copper exposure for 15 days in simplified soil solutions. A slight bioaccumulation of copper was observed in all treatments and controls. The effect of exposure concentration and calcium level on copper accumulation was not significant. Although pH and time slightly but significantly affected copper concentrations in the body, copper uptake rates were not significantly different from zero. This suggests that copper uptake in F. candida exposed to sub-lethal copper concentrations in soil pore water is not affected by pH and calcium. 相似文献
42.
Tabaripour Raheleh Sheidai Masoud Talebi Seyed Mehdi Noormohammadi Zahra 《Genetic Resources and Crop Evolution》2021,68(5):2003-2017
Genetic Resources and Crop Evolution - Hymenocrater comprises of 11 species throught the world. The genus is an Irano-Turanian elements, which has several usages in traditional medicine. Northeast... 相似文献
43.
Ebrahimi A Nikookhah F Nikpour S Majiian F Gholami M 《Pakistan journal of biological sciences: PJBS》2008,11(1):148-150
Streptococci are frequently isolated from bovine mastitis in dairy cows with only limited information available on the antimicrobial susceptibility of these organisms. A total of 42 Streptococci isolated from 148 milk samples of normal, sub acute and acute bovine mastitis cases. Overall, 35% of the strains tested were Streptococcus dysgalactiae, Streptococcus agalactiae 26%, Streptococcus uberis 18 and 4% were Enterococcus sp. Differences between the number of isolations in acute and sub acute groups were statistically significant, (p<0.5). The antimicrobial susceptibility for these organisms was determined for the following antimicrobial agents: cephalexine, penicillin, clindamycin, cloxaciline, gentamicin, streptomycin, amoxicillin, tetracycline, kanamycin, oxytetracycline, ampicillin, chloramphenicol and erythromycin. S. agalactiae, S. dysgalactiae, S. uberis and Enterococci demonstrated high level of resistance against streptomycin, penicillin and cloxaciline. Low level of sensitivity to other tested antimicrobials was demonstrated. 相似文献
44.
The predatory mite, Phytoseius plumifer (Canestrini & Fanzago), is one of the most abundant natural enemies and efficient predator of phytophagous mites in Iran. The miticides hexythiazox (Nisorun, EC 10%), fenpyroximate (Ortus, SC 5%), and abamectin (Vertimec, EC 1.8%) were tested in the laboratory for their side effects on P. plumifer. The miticides were applied at the highest field recommended concentration (N) to detached leaves using a Potter Tower to deposit 2 mg spray solution per cm2. Percent predator mortality was evaluated from the protonymph up to the adult stage including the first five days of the oviposition period. Analysis of data showed that the total effect values of hexythiazox were below the lower threshold, and thus it could be considered to be a harmless miticide to P. plumifer. In contrast, the total effects of fenpyroximate and abamectin were found harmful to the predatory mite at the highest field recommended concentrations. 相似文献
45.
The aim of this study was to determine the effects of dietary probiotics on reproductive performance, growth, haematological and biochemical parameters of female rainbow trout broodstock. A total of 60 broodstocks with an average initial weight of 2,267.4 ± 54.9 g were divided into four groups and three replicates in raceway ponds. Fish were fed with diets containing 0 (control), 1 × 109 (P1), 2 × 109 (P2) and 4 × 109 (P3) CFU probiotic per kg diet twice a day for 8 weeks before spawning season. Results revealed that higher levels of dietary probiotics (P3) enhanced protein efficiency ratio and decreased feed conversion ratio (p < .05). There were no significant differences in haematological and other growth parameters among different treatments. According to the results, probiotic‐fed treatments had the lowest levels of cholesterol (237.7 ± 4.3 mg/dl) and the highest levels of total protein (11.3 ± 0.3 g/dl) and albumin (6.9 ± 0.3 g/dl), so that differences were found between P3 and control groups in all cases (p < .05). Based on the observations from reproductive parameters, the highest egg diameter, working and relative fecundities, fertilization and hatching rates, eyed eggs survival and alevins survival rates up to the absorption of the yolk sac were observed in P3 treatment (p < .05). Moreover, eyeing, hatching and yolk sac absorbing stages in P3 treatment were earlier than those in other treatments (p < .05). The results of present study demonstrated that probiotic supplementation improved reproductive performance and some growth and biochemical parameters in female rainbow trout broodstock and the best performance was observed in fish fed 4 × 109 CFU probiotic per kg diet. Due to an increase in egg production and egg size in probiotic‐fed treatments, this feed additive can be used as a suitable ingredient to increase high‐quality egg production in rainbow trout breeders. 相似文献
46.
Mohammad Faraji Masoud Jafarizadeh Ali Mohammadian Behbahani 《Archives of Agronomy and Soil Science》2017,63(11):1523-1534
Although root crops are widely cultivated in Iran, little is known about soil loss due to crop harvesting (SLCH). We assessed the annual exported soil, soil organic matter (SOM) and nutrients from 47 farms under root crops in southwestern Iran. Soil losses for garlic, potato, sugar beet, radish and beetroot were estimated as 6.27, 2.52, 2.26, 4.10 and 6.95, Mg ha?1, respectively, which on average was of the order of soil losses by water erosion in the watershed basins of Iran. Total N, P2O5 and K2O losses were estimated as 36.61, 1.10 and 31.50 kg ha?1 and their costs as 18.24, 0.74 and 19.93 USAlthough root crops are widely cultivated in Iran, little is known about soil loss due to crop harvesting (SLCH). We assessed the annual exported soil, soil organic matter (SOM) and nutrients from 47 farms under root crops in southwestern Iran. Soil losses for garlic, potato, sugar beet, radish and beetroot were estimated as 6.27, 2.52, 2.26, 4.10 and 6.95, Mg ha?1, respectively, which on average was of the order of soil losses by water erosion in the watershed basins of Iran. Total N, P2O5 and K2O losses were estimated as 36.61, 1.10 and 31.50 kg ha?1 and their costs as 18.24, 0.74 and 19.93 US$ ha?1, respectively. For the whole country, total soil, N, P2O5, K2O and SOM losses for garlic, potato and sugar beet were estimated as 731.7 × 103, 836, 27, 476 and 14.5 × 103 Mg, respectively (radish and beetroot were excluded due to no reliable data on their planted areas). Correlation analysis showed no significant relationship between soil properties and SLCH (except soil moisture content for radish and clay content for beetroot). The findings indicated that the exported soil, SOM and nutrients were at such levels that SLCH should be considered in soil erosion studies. 相似文献
47.
Saeed Soheilivand Mohammad Reza Safarnejad Naser Farrokhi Mohsen Mardi Masoud Tohidfar 《The Journal of Horticultural Science and Biotechnology》2018,93(5):474-482
Preservation of elite key lime (Citrus aurantifolia) genotypes using efficient micropropagation and regeneration protocols is very important for new breeding programmes. The objective of the present study was to develop an efficient protocol for micropropagation and maintenance of elite genotypes of key lime based on slow growth and starvation strategy. To do this, regenerated shoots were starved, and the growth was compromised via avoiding subcultures for 4, 8, 12 and 24 months. The numbers of responsive explants and adventitious shoots per each explant were evaluated in the presence of benzylaminopurine (BAP). The results showed that the 12- and 24-month starved explants treated with 1 mg/l BAP were able to produce four times more shoots than the control. In addition, the influences of horizontal or vertical layering explants over medium were evaluated. The results indicated that all horizontally layered explants significantly produced 25% adventitious shoots more than vertical explants, most likely owing to more contact with the surface medium. Finally, it could be concluded that application of slow growth, starvation strategy and also horizontally layering of the explants could efficiently enhance micropropagation and maintenance of threatened elite key lime genotypes with a low cost. 相似文献
48.
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
49.
50.
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