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81.
Mehmet Cengiz Sarper Ozbek Muhammad Furqan Asghar Chacher 《Canadian journal of veterinary research》2022,86(1):74
This field study was conducted to compare conception and insemination efficiency responses to intrauterine polyvinylpyrrolidone-iodine (PVP-I) and antibiotic (AB) treatments in dairy cows that experienced pregnancy loss. Data were collected from lactation cows with a history of pregnancy loss 27 to 70 days post-insemination (n = 97) during the 1st to 3rd lactation (days in milk = 196 ± 28). Cows were subjected to 1 of 3 treatments: i) 50 mL saline solution intrauterine infusion (S; n = 23); ii) 2% PVP-I (n = 42); or iii) 150 mg of amoxicillin trihydrate and 40 mg/mL gentamicin sulphate (n = 32). All cows followed the progesterone-based fixed-time insemination protocol. Data were analyzed by Chi-square test and 1-way analysis of variance. The PVP-I treatment (n = 25; 59.5%) was as effective as the AB treatment (n = 19; 59.4%), compared to the S treatment (n = 5; 21.7%) to achieve a new conception. The cows in group PVP-I conceived in a shorter time than those in group AB (46.0 ± 8.7 days versus 105.0 ± 10.0 days; P < 0.05) with a more efficient insemination to conception ratio (2.32 ± 0.43 versus 4.10 ± 0.32; P < 0.05). Data suggest that intrauterine PVP-I administration is superior to intrauterine AB administration in rescheduling reproductive protocol upon late embryonic and fetal losses. 相似文献
82.
Sara Pourhosein Sarameh Bahram Falahatkar Ghobad Azari Takami Iraj Efatpanah 《Fish physiology and biochemistry》2013,39(5):1253-1266
Pikeperch broodstocks were exposed to different photoperiods: constant light (24L:0D), constant darkness (0L:24D), and 12 h light, 12 h darkness (12L:12D), for 40 days. Half of the broodstocks of each photoperiod were exposed to handling stress at a specific time of the day. Results showed that cortisol and lactate did not reveal any significant difference. However, glucose levels in females increased in the stress-free darkness period in comparison with stressful darkness photoperiods (0L:24D-s). Red blood cells in males and white blood cells in females showed a significant difference under different photoperiod regimes. Both sexes showed no significant difference in the differential count of leukocytes under different photoperiods and handling stress. Constant photoperiods and handling stress affected the hematological parameters, particularly, the number of lymphocytes and neutrophils in females. Our findings revealed that due to a long-term exposure to stressors, pikeperch brooders become adapted to stressful conditions. 相似文献
83.
Growth Performance and Body Composition of Aspikutum: A New Hybrid of Asp,Leuciscus aspius ♀, × Caspian Kutum,Rutilus frisii ♂, Cultured under Different Stocking Densities in Circular Concrete Tanks 
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下载免费PDF全文 Mohaddeseh Bagheri Bahram Falahatkar Iraj Efatpanah 《Journal of the World Aquaculture Society》2017,48(6):947-954
The first step for rearing the newly produced hybrid of Asp, Leuciscus aspius ♀, × Caspian Kutum, Rutilus frisii ♂ (so‐called “Aspikutum”) is to understand essential production requirements such as stocking density. For this purpose, fish (60.4 g) were held at five stocking densities of 2, 4, 6, 8, and 10 kg/m3 in circular concrete tanks (603 L) for a period of 56 d. The culture system was maintained at natural temperature and photoperiod. Fish were fed thrice a day using a commercial diet. At the end of the trial, growth indices, including final mean weight, weight gain, and specific growth rate, were significantly higher at the density of 10 kg/m3 compared with 2 kg/m3 (P< 0.05). Feed intake was significantly greater at 10 kg/m3 compared with 2 kg/m3 (P< 0.05); however, feed efficiency, protein efficiency ratio, protein productive value, and hepatosomatic index remained unchanged among the stocking densities (P> 0.05). Increased stocking density caused significant increase in body protein and fat contents (P< 0.05). Condition factor in higher densities (8 and 10 kg/m3) was significantly higher compared with 2 kg/m3 (P< 0.05). The results indicated that rearing this hybrid in the studied weight range at high density of 10 kg/m3 or more is possible without negative impacts on growth performance and body composition. 相似文献
84.
Reproduction efficacy of sturgeon as donors of oocytes is regulated by hormones effects. It can influence the egg quality or larvae functions as rearing mediators for successful production. This study is conducted to evaluate the concentration of sex steroids, cortisol and thyroid hormones and distinguish the relationship of maternal hormones' correlation in Stellate sturgeon. The study followed the hormones fluctuations that could impress some egg quality information such as fertilization rate. Female breeders were injected with LHRHa2 for controlled propagation. Samples from blood, ovarian fluid and oocytes were obtained for hormonal and biochemical analysis. Our results showed that the concentrations of estradiol 17‐β and testosterone were significantly higher and lower in oocyte and the plasma, respectively. The level of plasma cortisol was significantly higher than in ovarian fluid and oocytes. The results showed elevation of triiodothyronine and thyroxine concentrations in oocytes, which were significantly different with plasma and ovarian fluid. Thyroxine concentration of plasma and ovarian fluid revealed a significant negative correlation. The mentioned parameters showed negative correlation with fertilization rate. The biochemical parameters (calcium, glucose, cholesterol and triglyceride) revealed significant differences in blood, ovarian fluid and oocytes. These results showed direct relations of fertilization rate with hormones level. Therefore, fertilization rate as egg quality index could be recommended as a relevant indicator of maternal transferring of hormones from blood and ovarian fluid to oocyte. 相似文献
85.
An investigation was accomplished to find the effects of different sizes as a social stress on physiological responses and growth performance of Siberian sturgeon. Juvenile Siberian sturgeon were separated into two sizes (860.88 ± 22.32 g as larger fish and 427.28 ± 2.97 g as smaller fish). Three treatments including large size (L), small size (S), and mixed size (M) were considered. There were equal numbers of large and small fish in the M treatment. Sampling was carried out at 1st week (as a short‐term sampling) and 8th week (as a long‐term sampling) of the experiment. At the end of each sampling, haematocrit, glucose, cholesterol, triglyceride, total protein, lactate, and cortisol were measured. All growth parameters and feed utilization in large fish were not affected in the M treatment compared with the L treatment and also small fish in the M treatment compared with the S treatment. The final biomass in the S treatment was significantly higher than those in the L and M treatments. Haematocrit, glucose, cholesterol, triglyceride, total protein, lactate, and cortisol in the 1st week showed no significant difference with different sizes. However, in the 8th week, only haematocrit increased (by time not size) in the S treatment. Fish in the M treatment in both sizes did not experience the stress condition. Larger and smaller sizes had a positive social interaction; therefore, different sizes of Siberian sturgeon can maintain together without decreasing growth rate and also adverse physiological responses. 相似文献
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87.
Emily J. Lindsay Douglas J. King Andrew M. Davidson Bahram Daneshfar 《Strength and Conditioning Journal》2019,72(1):92-102
Rangeland and seeded forage in Canada’s Prairie provinces represent productive landscapes that provide multiple ecosystem services. Past efforts to map these resources at regional scales have not achieved consistently high accuracies as they are spatially variable in both ecology and management. In particular, Agriculture and Agri-food Canada needs to distinguish these land use classes from each other and from cropland in its annual national agricultural land cover inventory. Given the potential to distinguish these classes based on seasonal phenological differences, this study used multi-season Landsat 8 top-of-atmosphere reflectance data and derived vegetation and phenological indices, as well as mid-summer RADARSAT-2 data in random forest classification of two ecoregions in Alberta and Manitoba. Classification accuracy was compared for single and multi-date Landsat 8 variables, the vegetation index and phenological variable groups, RADARSAT-2 VV and VH backscatter intensity, and combined datasets. Variable importance analysis showed that spring Landsat 8 reflectance generally contributed most to class discrimination, but accuracy improved with the addition of Landsat 8 data from the other seasons. Vegetation indices and phenological variables produced similar accuracies and were deemed to not warrant the additional processing effort to derive them. RADARSAT-2 VH backscatter was the most important variable for the Manitoba study area, which is wetter with more vegetation structure variability than the Alberta study area. Backscatter intensity significantly increased overall accuracy when it was combined with one or two-season Landsat 8 data. The best overall accuracy was achieved using the three seasons of Landsat 8 and mid-summer RADARSAT-2 data, but it was not significantly better than that for two season Landsat 8 + RADARSAT-2. The methods presented in this paper provide a process for accurate and efficient classification of seeded forage, rangeland and cropland that can be applied over large areas in operational agricultural land cover inventory. 相似文献
88.
Bahram Baninasab 《The Journal of Horticultural Science and Biotechnology》2013,88(3):191-196
SummarySalicylic acid (SA) is a common, plant-produced signal molecule that is responsible for inducing tolerance to a number of biotic and abiotic stresses. An experiment was therefore conducted to test whether the application of SA at various concentrations (0, 0.25, 0.50, 0.75, or 1.00 mM) by seed soaking, or as a foliar spray would protect cucumber (Cucumis sativus L.) seedlings subjected to drought stress. Thirty-six-day-old seedlings (n = 12 seedlings per treatment) were exposed to drought stress for 14 d. Pretreatment with SA improved the majority of the physiological (e.g., relative chlorophyll content and chlorophyll fluorescence ratio) and morphological parameters (e.g., shoot and root fresh and dry weights) measured in cucumber seedlings subjected to drought stress. SA ameliorated the injuries caused by drought stress by increasing shoot tissue proline contents and preventing an increase in leaf electrolyte leakage. SA was more effective at increasing the drought tolerance of cucumber seedlings when applied using the seed-soaking method, rather than as a foliar spray. The best drought protection appeared to be obtained when seeds were soaked in 0.50 mM SA. 相似文献
89.
Reza Faramarzi Hafez Zeynab Shahabzadeh Bahram Heidari Morteza Ghadimzadeh 《Journal of Crop Science and Biotechnology》2013,16(4):291-296
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
90.
Background: Pectic acid extracted from plants increases the secretion of prolactin (PRL) when injected intravenously into ewes or fed to rats. Fragments of ewe hypophysis and lactating rabbit mammary gland incubated in vitro in the presence of pectic acid secreted more PRL and caseins compared to the controls. However, it is not known whether pectic acid directly stimulates PRL secretion in pituitary or interference of factors from hypophysis is required for this process. Methods: GH3/B6 cells, a clonal strain of rat pituitary, were cultured and incubated with pectic acid (2.5-100 mug/mL). The integrity of cells was examined under pectic acid treatment microscopically. Controls or pectic acid treated cells were assayed for their ability to produce PRL. The PRL was assayed by Western-blotting and Radioimmunoassay. Results: pectic acid did not have any significant effect on the viability of cells. After being incubated with pectic acid, the cells started to become circular and protuberant shape. The maximum stimulation and PRL secretion occurred at 100 mug/mL concentration within 30 min of incubation with pectic acid. Conclusion: pectic acid could stimulate the release of PRL in GH3/B6 cells in the short-term incubation. This result suggested that pectic acid is a non-toxic agent that could directly stimulate PRL secretion in pituitary cells without any interference of hypophysis. 相似文献