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11.
The effects of moisture content (8%, 10%and 12%), variety (Tarom and Fajr) and parboiling on milling quality of rice as a function of milling recovery (MR), head rice yield (HRY), degree of milling (DOM) and whiteness were investigated. The parboiled grains was prepared with three soaking temperatures of 25 oC, 50 oC and 75 oC and three steaming times of 10, 15 and 20 min. As a result of parboiling, the increasing rates of MR and HRY values were 7.8%and 14.3%for Tarom and 9.8%and 10.0%for Fajr, respectively, and the decreasing rates for DOM and whiteness were 6.6%and 10.8%for Tarom and 6.8% and 10.5% for Fajr, respectively. Moreover, decreasing moisture content to 8%maximized MR (75.8% for Tarom and 74.3% for Fajr) and HRY (65.8% for Tarom and 57.0% for Fajr) while increasing that to 12%revealed maximum values of DOM (6.1%for Tarom and 6.2%for Fajr) and whiteness (24.8%for Tarom and 28.2%for Fajr).  相似文献   
12.
This study was undertaken to study the effect of Satureja khuzestanica essential oil (SKEO) in male rat fertility. SKEO was administered orally at doses of 75, 150, and 225 mg/kg/day for 45 days through drinking water. Treated and control rats were mated with female on day 45 of treatment. SKEO significantly improved all the parameters evaluated such as potency, fecundity, fertility index, and litter size. Moreover, concentrations of FSH and testosterone were significantly increased in SKEO-treated groups. Also the weights of testes, seminal vesicles, and ventral prostate weights were increased by SKEO (225 mg/kg). Histopathological analysis showed that in male rats treated with SKEO (150, 225 mg/kg) the number of spermatogonium, spermatid cords, Leydig cells, and spermatozoids was increased. Also in these groups, the Sertoli cells were hypertrophic.  相似文献   
13.
Relationships between insulin-like growth factor-I (IGF-I) and thyroxine (T4) and cortisol hormones were studied in female brood stocks of Persian sturgeon [Acipenser persicus; caught from both sea water (SW) and fresh water (FW)] during late stages of sex maturation. A number of biometrical traits were also studied that could represent the reproductive and/or growth states of brood stocks, and the possible relationship between IGF-I and growth was assessed in juvenile Persian sturgeons between 1 and 4 years of age. IGF-I, T4 and cortisol were measured in serum samples using commercially available kits. A four-parameter logistic model test was performed between the standard curves and the sample dilutions for each hormone. Parallelism, linearity and regression coefficients for the linearized standard curves and serial dilutions of samples were not significantly different (P < 0.05). Serum IGF-I levels in the juveniles were higher than those in the SW brood stocks, and cortisol levels in the former were lower than those in both brood stocks (P < 0.05). T4 levels in serum samples of juveniles were below the detectable level. IGF-I concentrations in juveniles were correlated with total weight, total length and fork length, but they did not increase significantly with increasing age from 1 to 4 years old (P < 0.05). Compared with SW brood stock, the FW brood stock was younger, had a smaller girth, smaller polarization index and higher ova diameter (P < 0.05). There were no differences between IGF-I and T4 levels in the two brood stocks, but cortisol levels were significantly higher in the FW brood stock. Percentage of fertilization was correlated with serum IGF-I in both brood stocks (P < 0.05). Our results support a role for IGF-I during the juvenile growth and reproductive physiology in female brood stocks of the Persian sturgeon.  相似文献   
14.
Sperm density, mineral and organic composition of the seminal plasma and their physiological relationship were investigated in the Caspian brown trout (Salmo trutta caspius). To establish a rapid and accurate method for assessment of sperm density, three different techniques were used: sperm counting, spectrophotometry (at 480 nm) and determination of the spermatocrit. The seminal plasma contained 159.26±8.84 mM sodium (Na), 33.72±2.01 mM potassium (K), 133.04±5.96 mM chlorine (Cl), 1.68±0.2 mM calcium (Ca) and 0.988±0.13 mM magnesium (Mg). The following organic components were found: total protein 0.75±0.14 mg 100 mL−1, cholesterol 2.86±0.58 mg L−1 and glucose 3.81±1.04 mM L−1. The mean sperm density was estimated to be 3.3 × 109 spermatozoa mL−1. The spermatocrit (%) ranged from 25 to 52 in sperm samples. Highly significant linear relationships were found between sperm density and spermatocrit (R2=0.703, P<0.001) and sperm density and optical density (R2=0.909, P<0.001), indicating that optical density can be used as a quick and accurate method of estimating sperm density. Significant relationships were also found between sperm density and Ca, Mg and total protein of seminal plasma. A significant correlation was also observed between the Ca and Mg concentrations (R2=0.774, P<0.01). The following correlations were observed between mineral and organic components: total protein and Ca (R2=0.462, P<0.05), total protein and Mg (R2=0.518, P<0.05) and glucose and Cl (R2=0.374, P<0.05). These parameters should be considered when developing procedures for either artificial fertilization or for cryopreservation of sperm.  相似文献   
15.
Interactions of 17 sugar beet lines and cultivars with four isolates of Macrophomina phaseolina (the causal agent of charcoal rot) and one isolate of Rhizoctonia solani (the causal agent of crown and root rot) were studied in separate experiments under greenhouse conditions. The isolates of Macrophomina were taken from their host plants, sugar beet (two isolates), soybean and sesame. In the first experiment, the colonized toothpick was used as inoculum. In the second experiment, six-month-old sugar beet plants were inoculated with barley seeds colonized with M. phaseolina. For the inoculation of sugar beet lines with R. solani, the colonized corn seeds were used. Root symptoms were recorded four weeks after inoculation, by estimating the proportion of the root surface infected by the pathogens, using a 1–9 standard scale. Our results showed a significant difference among lines and cultivars in their resistance to these two pathogens. Line B8618 was found to be considerably resistant to the isolates of the both pathogens. The inoculation methods of Macrophomina isolates had no significant effect on the results. The interaction between isolate and cultivar was not also significant in Macrophomina-resistant lines. Therefore, it appears that the response of sugar beet lines to the tested fungal isolates was not differential. These resistant lines showed a high resistance to all the tested M. phaseolina isolates. Our results revealed that the Macrophomina-resistant lines also showed resistance to R. solani. Furthermore, the sugar beet drought tolerant lines (M293, M362 and M345) were susceptible to the tested M. phaseolina and R. solani isolates.  相似文献   
16.
Long‐day photoperiods are considered as an effective managerial tool in manipulating of reproduction and somatic growth in a number of fish species. In this study, the effects of three different artificial photoperiods on the gonadal development and somatic growth of rainbow trout (Oncorhynchus mykiss L.) were investigated. Two years‐old immature female rainbow trout (279.94 ±2.25 g) were exposed to three artificial photoperiod regimes of 24L:0D, 18L:6D and 6L:18D and natural light (NL) regime for 5 months. The highest gonadosomatic indices were recorded in NL and 6L:18D groups while the rates were significantly lower in fish maintained under 18L:6D and 24L:0D photoperiods (< 0.05). Mean oocyte diameters in fish exposed to 24L:0D and also to 18L:6D were significantly lower than the 6L:18D and NL groups. Photoperiods with 24L:0D and 18L:6D regimes resulted in significantly higher mean final weights and specific growth rates (SGR) than NL regime. The highest mean final weight (635.45 ± 16.19 g) and SGR (1.03 ± 0.04% day?1) were obtained under 24L:0D photoperiod. Fish exposed to 24L:0D and 18L:6D showed the highest condition factor as 1.44 ± 0.01 and 1.44 ± 0.02 respectively, when compared with the NL (1.27 ± 0.01) and 6L:18D (1.34 ± 0.02) groups. Basically, the results suggested that continuous artificial lightning can be used as an influential factor in delaying gonadal development and enhancing somatic growth in rainbow trout during gonadal growth phase.  相似文献   
17.
Identification of resistance resources of sugar beet germplasm against Polymyxa betae has always been a critical concern among sugar beet breeders. In the present study, two different methods including the DAS-enzyme-linked immunosorbent assay (ELISA) test and a nanobiosensor method based on florescent resonance transfer energy (FRET) were compared in order to achieve resistant germplasm. More specifically, 58 sugar beet germplasm as well as two negative and two positive controls were cultivated in infested soil under greenhouse conditions. The contamination level or in another words sensitivity and specificity observed based on the ELISA readings was inaccurately lower in comparison with the investigated nanobiosensor. Moreover, the nanobiosensor was 70 folds less time consuming compared to the ELISA method, for the immuno-reaction was much faster and no sample treatment steps were required. As a result, the quantum dots-FRET-based nanobiosensor investigated herein could well suit the task of everyday screening of resistance resource and could be efficiently used in breeding programs.  相似文献   
18.
Viral disease of rhizomania is one of the most important diseases of sugar beet all over the world. The disease significantly has reduced the yield and quality of sugar beet, and has imposed high economic loss to farmers. Long-term breeding programs to introduce tolerant cultivars are the only chance of avoiding further yield losses. This study tried to measure and analyze the growth of shoots and roots of rhizomania-tolerant and -susceptible sugar beet with the aim of providing information for modeling of the rhizomania effects on the growth of sugar beet. Growth indices were used for analyzing, quantification, and time-course of sugar beet growth under infested and non-infested soils conditions. A 2-year experiment was conducted using four sugar beet cultivars in 2010 and 2011 in Mashhad, Iran. The results of this study showed that under infested soils, root dry matter and leaf area index of the susceptible cultivars in comparison to tolerant cultivars were lower by 57 and 24%, respectively. In addition, crop growth rate and net assimilation rate of susceptible cultivars were affected by rhizomania and were lower than in tolerant cultivars. On non-infested soil, the difference between dry matter and growth indices of susceptible and tolerant sugar beet cultivars was not significant. Rhizomania decreased green area and photosynthesis capacity and led to lower growth rate and dry matter production. Our study quantified the growth of rhizomania-infested sugar beet plants in comparison with non-infested plants and provided information to be used for modeling of the rhizomania effects on the growth of sugar beet.  相似文献   
19.
Hyperglycemia is observed with exposure to organophosphorus (OP) pesticides. The aim of this study was to investigate the effects of malathion on secretion of insulin from rat pancreatic islets in vitro and in vivo. Malathion was administered through food for 4 weeks at concentrations of 100, 200, and 400 ppm. For in vivo experiment, at the end of treatment, blood sample was obtained and plasma was separated. For in vitro experiment, the treated rats were anesthetized and underwent a laparatomy. The common bile duct was cannulated and the pancreas distended by injecting of cold collagenase V using peristaltic infusion pump. Islets were then hand picked under a stereomicroscope and cultured in the presence of various doses of glucose and KCl. Malathion at doses of 200 and 400 ppm increased plasma glucose and insulin concentrations and lowered activity of erythrocyte acetylcholinesterase. The isolated islets from pretreated animals with malathion 200 and 400 ppm showed lower glucose-stimulated insulin secretion while no change was observed in the presence of KCl. Light microscopic examination revealed that malathion causes patchy degenerative changes in pancreatic islets. Combination of in vivo and in vitro findings suggests that malathion induces a kind of insulin resistance that cannot overwhelm hyperglycemia. This action of malathion is mediated through disruption of islets mitochondrial function.  相似文献   
20.
To determine the effect of gonadotropin releasing hormone‐analogue (GnRHa) treatment on the milt quality of endangered Caspian brown trout, Salmo trutta caspius, the sperm motility (percentage and duration of motility), sperm production (sperm density, spermatocrit and milt volume) and milt pH were measured for GnRHa‐treated (the treatment group) and untreated groups (the control group) during the spawning season. For untreated brooders, the values of the motility per cent, sperm density and spermatocrit decreased continuously during the spawning season while the milt volume, duration of motility and milt pH showed only a significant decrease at the end of the season. For GnRHa‐treated males, these parameters increased 14 days after GnRHa treatment (first milt collection) and then decreased continuously towards the end of the season. In addition, the values of milt and sperm density yielded per treated male were higher than that in the untreated group, although these were not statistically different. In any case, the total sum of yielded milt from the treatment group over the spawning season was higher than that in the untreated group. In this experiment, significant positive correlations were found between milt parameters as follows: sperm motility vs. milt pH; sperm density vs. spermatocrit; milt volume vs. spermatocrit; and milt volume vs. sperm density. The results show that the treatment of Caspian brown trout by GnRHa can improve the milt quality in terms of sperm motility and sperm production during a spawning season.  相似文献   
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