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121.
Two experiments were conducted to evaluate the efficacy of clove solution on anesthesia and hematological parameters in Beluga, Huso huso (L.). In the experiment 1, fish were exposed to concentrations of 300, 500, 700, 1,800 and 3,000 ppm clove solution and induction (stage 3 and 4) as well as recovery period lengths were recorded. These concentrations were led to induction and recovery time between 42–365 and 125–235 s, respectively, in dose-dependent manner. There was negative correlation between induction and recovery time (R 2 = 0.92). In the experiment 2, fish were exposed to each aforementioned concentrations and let to reach stage 4 anesthesia and then blood-sampled. Control group was sampled without anesthesia. Hematological studies between groups showed no significant changes in white blood cell (WBC) and differential leukocyte count (P > 0.05). Hematocrit (Hct), hemoglobin (Hb), red blood cell (RBC) and mean corpuscular hemoglobin concentration levels were significantly high in concentrations of 300–700 ppm compared to control, 1,800 and 3,000 ppm. Control and 500–3,000 ppm groups have similar mean corpuscular volume values and significantly higher than 300 ppm. Lower values of mean corpuscular hemoglobin were related to control, 3,000 and 1,800 ppm and higher values were observed in the others. Strong positive correlation were observed between induction periods and Hct, Hb and RBC levels (R 2 = 0.095, 0.99 and 0.92, respectively). Results suggested that anesthesia with low concentrations of clove solution over a long period is stressful compared to high concentrations over short period.  相似文献   
122.
As a medicinal plant, the importance of evening primrose (Oenothera biennis L.) is due to its unsaturated fatty acids in the seeds and roots, and also oenotherine and comfarol in the leaves. Low germination and difficulties in seed production are the main problems encountered with growing this plant in the field. As an alternative approach, an in vitro experiment was set up for the evaluation of evening primrose production via direct and indirect regeneration of the cultivars NC-1 and VNK. For callogenesis and direct regeneration, the explants from the apical bud and petiole were cultured on MS medium supplemented with 0.25, 0.75, and 1.25 mg L?1 of both BAP and Kinetin (KIN). Indirect regeneration was performed by placing apical buds, petioles, and leaf explants on MS medium supplemented with 0.5 and 1 mg L?1 2,4-D and 0.5, 1, and 1.25 mg L?1 of both BAP and KIN. The highest shoot induction from direct regeneration was obtained with apical bud explants of VNK treated with 0.75 mg L?1 BAP. The highest callus weight (3.17 g) obtained from indirect regeneration was with petiole explants treated with 1 mg L?1 2, 4-D and 1 mg L?1 BAP in VNK cultivars. The highest number of torpedo embryogenic clusters (23.8) was obtained from the VNK petiole explants treated with 0.5 mg L?1 2, 4-D and 1.25 mg L?1 BAP. BAP had higher positive effects on in vitro production of evening primrose than KIN in both direct and indirect regeneration. In general, results indicated that VNK was more potent for regeneration than NC-1 and concentrations of 0.75 mg L?1 BAP for direct and 0.5 mg L?1 2, 4-D and 1.25 mg L?1of BAP for indirect regeneration had a higher efficiency for increasing in vitro production of evening primrose.  相似文献   
123.
Journal of Plant Diseases and Protection - Nutrient elements have a significant role in plant physiology and metabolism, and the concentration of nutrients in the plant depends on plants genetic...  相似文献   
124.
The aim of this study was to investigate the development of the pupillary light reflex in neonatal calves and the effect on the development of the menace response of keeping them in individual stalls. Seventy-three Holstein calves were divided into test (n = 44) and control (n = 29) groups and the animals were kept in individual stalls for the first 32 ± 4 and 73 ± 5 days post partum, respectively. They were then moved to group pens. All calves in both groups were observed daily from the first day after birth until the pupillary light reflex and menace response had become well established.All 73 calves had a positive pupillary light reflex on the first day post partum. None of the animals developed a menace response during the time they were housed in individual stalls. Over 14 days (test group) and 12 days (control group) after the calves had been moved to the group pens they became positive to the menace response at ages 41 ± 4 and 81 ± 5 days, respectively. The Mann–Whitney test revealed a significant difference (P < 0.001) in the ages of the calves with positive menace responses between groups. Group rearing may produce more visual threats to the eyes and the calves learn the menace response by closing the lids in response to sudden alarming movements.  相似文献   
125.
[目的]基于微量元素在水稻营养和代谢中的重要作用,研究叶面喷施(Fe EDTA 0.1%,Zn EDTA 0.05%,B 0.02%,Cu EDTA 0.05%,and Mn EDTA 0.05%)对水稻品种Shiroodi产量的影响,明确叶面喷施微量元素的最佳次数和时期.[方法]为了准确评估液体肥料(Fe-EDTA ...  相似文献   
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