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101.
This study was conducted to evaluate the Salvia officinalis hydroalcoholic extract on fertility capacity and behavioral features in rats exposed to immobilization stress. Male rats were randomly divided into five groups; Control; Stressed rats; and Stressed rats received 50, 100 and/or 200 mg/kg bw S. officinalis hydroalcoholic extract. To induce stress, rats were immobilized for 49 days and received S. officinalis extract orally. On day 56, we analyzed behavioral tests and evaluated reproduction capacity by measuring LH, FSH, and testosterone. Sperm parameters such as motility, viability, and total count were also determined. Bodyweight changes were also calculated on day 56. Male rats from different groups were mated with healthy female rats. Data showed that the use of 100 and 200 mg/kg bw S. officinalis extract in stressed rats increased bodyweight gain and improved behavioral disorders compared to control‐matched groups (p < .05). Besides, administration of 100 and 200 mg/kg bw S. officinalis extract had the potential to improve sperm parameters and fertility capacity in stressed rats (p < .05). Decreased testosterone levels were blunted in the stressed rats that received plant extract coincided with the reduction of LH and FSH compared to control‐matched stressed rats (p < .05). We found neutral effects in stressed rats that received 50 mg/kg bw plant extract. Collectively, the hydroalcoholic extract of S. officinalis could improve the fertility capacity and behavioral features under stressful conditions in a dose‐dependent manner.  相似文献   
102.
In the present study, genetic diversity of 48 individual plants from four Iranian cultivated populations of alfalfa (Medicago sativa L.) was evaluated using sequence-related amplified polymorphism (SRAP) markers. Fourteen SRAP primer combinations produced 193 fragments of which 95 were polymorphic. The number of polymorphic fragments detected per primer combination ranged from 3 to 10 bands with an average of 6.78 bands. Average polymorphic information content (PIC) was 0.343 for all primer combinations. Although the AMOVA (analysis of molecular variance) results showed a significant difference in the genetic diversity among the populations (P < 0.0001), the genetic variation mainly caused by the variation of intra population accounted for 93.17% of the total genetic variation. Unweighted pair-group method arithmetic average (UPGMA) analysis of the marker data clearly separated the populations of subtropical (Yazdi) and semi-cold (Hamadani and Nikshahri) as well as Kodi, an improved population. It can be concluded that SRAP markers are useful for studying diversity and relationships among and within alfalfa populations.  相似文献   
103.

Milk has a high nutritional value and can affect human health. Therefore, it is important to know the factors affecting its quality. The purpose of this study was to evaluate the raw milk microbial quality and factors affecting it. A total of 4260 raw cow milk samples, which were collected from villages around Garmsar city, Iran, and their microbial load were registered at Garmsar Dairy Cow Association between 2013 and 2014, was used in the present study. The total average ± SD of microbial load concentration was 3.02?×?105?±?2.75?×?105 (CFU/ml). The average concentration of total bacteria in 2013 was 2.73?×?105?±?1.58?×?105 (CFU/ml) and in 2014 it was 3.32?×?105?±?3.93?×?105(CFU/ml). Seasonally, it was 2.94?×?105?±?1.72?×?105 (CFU/ml), 3.69?×?105?±?4.55?×?105 (CFU/ml), 2.91?×?105?±?1.62?×?105 (CFU/ml), and 2.63?×?105?±?1.67?×?105 (CFU/ml) for spring, summer, autumn, and winter, respectively. There was a significant difference in seasonal average microbial concentration of milk samples (p?<?0.05). The present study concludes that microbial load of milk can be affected by environmental and hygienic conditions. Ranchers need to pay more attention to hygiene especially in warm seasons. Because in case of high microbial load in raw milk, even after milk pasteurization, it is not possible to have a high-quality and desirable product. Milk producers and distributors need also awareness in order to reduce the incidence of secondary contamination. But, the main correction is to establish direct supervision of the Ministry of Health onto the health of dairy cow farmers by structural integrity of Veterinary Medical Organization as the global one health.

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104.
105.
Estimation of above-ground biomass is vital for understanding ecological processes. Since direct measurement of above-ground biomass is destructive, time consuming and labor intensive, canopy cover can be considered as a predictor if a significant correlation between the two variables exists. In this study, relationship between canopy cover and above-ground biomass was investigated by a general linear regression model. To do so, canopy cover and above-ground biomass were measured at 5 sub-life forms(defined as life forms grouped in the same height classes) using 380 quadrats, which is systematic-randomly laid out along a 10-km transect, during four sampling periods(May, June, August, and September) in an arid rangeland of Marjan, Iran. To reveal whether obtained canopy cover and above-ground biomass of different sampling periods can be lumped together or not, we applied a general linear model(GLM). In this model, above-ground biomass was considered as a dependent or response variable, canopy cover as an independent covariate or predictor factor and sub-life forms as well as sampling periods as fixed factors. Moreover, we compared the estimated above-ground biomass derived from remotely sensed images of Landsat-8 using NDVI(normalized difference vegetation index), after finding the best regression line between predictor(measured canopy cover in the field) and response variable(above-ground biomass) to test the robustness of the induced model. Results show that above-ground biomass(response variable) of all vegetative forms and periods can be accurately predicted by canopy cover(predictor), although sub-life forms and sampling periods significantly affect the results. The best regression fit was found for short forbs in September and shrubs in May, June and August with R~2 values of 0.96, 0.93 and 0.91, respectively, whilst the least significant was found for short grasses in June, tall grasses in August and tall forbs in June with R~2 values of 0.71, 0.73 and 0.75, respectively. Even though the estimated above-ground biomass by NDVI is also convincing(R~2=0.57), the canopy cover is a more reliable predictor of above-ground biomass due to the higher R~2 values(from 0.75 to 0.96). We conclude that canopy cover can be regarded as a reliable predictor of above-ground biomass if sub-life forms and sampling periods(during growing season) are taken into account. Since,(1) plant canopy cover is not distinguishable by remotely sensed images at the sub-life form level, especially in sparse vegetation of arid and semi-arid regions, and(2) remotely sensed-based prediction of above-ground biomass shows a less significant relationship(R~2=0.57) than that of canopy cover(R~2 ranging from 0.75 to 0.96), which suggests estimating of plant biomass by canopy cover instead of cut and weighting method is highly recommended. Furthermore, this fast, nondestructive and robust method that does not endanger rare species, gives a trustworthy prediction of above-ground biomass in arid rangelands.  相似文献   
106.
A field experiment was carried out with a split plot arrangement based on a randomized complete block design with three replications in 2014. Triple super phosphate (0, 3.75, 7.5, 11.25 and 15 g m?2) was applied in main plots and phosphate bio-fertilizer (seed inoculation and topdressing) was allocated to sub plots. Results indicated that application of plants with phosphorus (P) bio-fertilizer as topdressing increased plant height and the number of the lateral branches under low levels of chemical P fertilizer, while plants from seed inoculated with P bio-fertilizer had more of those traits under high levels of chemical P fertilizer. Maximum leaf and flower dry weights were found under the lowest level of chemical P fertilizer. Moldavian balm plant demonstrated highly responsiveness to biological fertilizers in terms of increase in essential oil (EO) percentage and yield. It can be concluded that the effects of bio-fertilizer as seed inoculation is more during the early vegetative growth of plants. Thus, plants from seeds inoculated with P bio-fertilizer treatment had more biomass and EO percentage under high levels of chemical P fertilizer.  相似文献   
107.
Nanoparticles (NPs) affect most soil properties but there have been no assessments of their effects on the compression behavior of soil and the strength of aggregates. Therefore, we assessed the impact of NPs on the bulk density and the confined compression and tensile strength of aggregates of a calcareous loamy soil. Using a factorial design, we assessed the effects of two factors on the soil properties, i.e., NP type (first factor) at two levels comprising Fe nano-oxide (Fe3O4, N1) and Mg nano-oxide (MgO, N2), and treatment amount (second factor) at four levels with dry mass percentages of 0%, 1%, 3%, and 5%. The soil bulk density increased with the Fe level but decreased with the Mg level in ranges of 0.02–0.04 and 0.02–0.08 g cm–3, respectively. The compression curve characteristics were not affected by the NPs. Compared with N1, the N2 treatment significantly increased the soil void ratio in 86% of the applied stresses. N1 also significantly enhanced the soil tensile strength at suctions of 30, 100, and 1500 kPa, ranging from 0.5 to 15.3 kPa. The 3% Mg and 1% Fe dosages of nano-oxides had the optimal effects, so they should be considered in future investigations.  相似文献   
108.
It has been proposed that glutathione can relieve the effects of Fe deficiency. This study tested the effects of glutathione foliar treatments to prevent Fe chlorosis, using as positive controls soil and foliar Fe fertilisation. Medicago scutellata plants were grown in soil (5.7% CaCO3) supplemented or not with 4 and 8% CaCO3. Two Fe(III)‐EDDHA soil treatments (5 and 10 mg Fe kg?1), and three foliar treatments (three applications each of 2.14 mM Fe(III)‐EDDHA, 1 mM glutathione, and the previous two combined) were applied. Measurements include leaf chlorophyll and Fe concentrations, biomass, leaf enzymatic and non‐enzymatic antioxidant systems and carboxylates. The addition of CaCO3 caused typical Fe deficiency symptoms, including changes in chlorophyll, Fe, antioxidant systems and carboxylates, which were prevented by soil and foliar Fe fertilisation. The foliar treatment with glutathione also led to higher chlorophyll, leaf extractable Fe and root Fe, as well as decreases in some antioxidant systems, whereas leaf Fe concentrations decreased. The combined foliar application of glutathione and Fe was even more efficient in preventing chlorosis. Including glutathione in foliar fertilisation programs should be considered as an option for Fe chlorosis prevention, especially when relatively large leaf total Fe concentrations occur in the so called chlorosis paradox.  相似文献   
109.
A monoclonal antibody blocking enzyme-linked immunosorbent assay (B-ELISA) was developed to detect antibodies to Mycoplasma bovis in cattle sera. The assay was highly specific and sensitive and there was no cross-reaction detected. This method revealed a high prevalence of antibodies (60%) to M. bovis in dairy cattle in North Queensland. The diagnostic potential of this B-ELISA for the detection of antibody to M. bovis was compared with its detection by PCR. There was a strong positive correlation between PCR and B-ELISA titers. Thus, the B-ELISA appears to be a valuable and reproducible tool in the serodiagnosis of M. bovis infection in cattle.  相似文献   
110.
This study was performed to compare the onset and duration of analgesia produced by either a lidocaine−MgSO4 or lidocaine−distilled water combination administration in the caudal epidural space of horse. Seven healthy adult horses, aged 11.7 ± 1.4 years (mean ± SD), body weight (kg) 567 ± 32.5 (mean ± SD), were selected for this study. Caudal epidural anesthesia was produced in all horses by administering 2% lidocaine (0.22 mg/kg) diluted in 1 mL distilled water and repeated with 2% lidocaine (0.22 mg/kg) diluted in 1 mL 10% MgSO4 2 weeks later. Time to onset (minutes), duration (minutes), and cranial spread of epidural analgesia were recorded. Heart rate (HR), respiratory rate (RR), and body temperature (°C) were recorded. Measurements were taken at 0 (as a baseline value before epidural administrations) and at 5, 10, 15, 30, 60, and 75 minutes after the epidural administrations of each treatment. Statistical analyses included paired Student t test and analysis of variance (computer program SPSS, Analytical Software, version 15.00). Statistical significance was set at P < .05. Onset of analgesia was significantly different (P < .001) between lidocaine-distilled water (2.38 ± 0.47 minutes) and lidocaine−MgSO4 (4.62 ± 0.54 minutes). Duration of analgesia after lidocaine−MgSO4 (186.0 ± 7.0 minutes) was longer than lidocaine-distilled water (54.5 ± 7.3 minutes). No significant differences were recorded for HR, RR, and body temperature in comparison with baseline values for each group. Using the lidocaine−MgSO4 combination for obstetric and surgical procedures could commence relatively soon after epidural injection and could be completed without readministration of anesthetic agent.  相似文献   
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