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101.
The aim of this study was to investigate the molecular mechanism behind androgen-induced sex reversal and growth increase in Nile tilapia. Three-day-old mixed-sex tilapia juveniles were treated with differential dose (0, 5, 10, 20, 30 mg/kg diet) and duration (0, 15, 30, 45, 60 days) regimes of 17α-methyltestosterone. Treatment regimes 10, 20, 30 mg/kg-30, 45, 60 days showed ~95% males, while 0 mg/kg-0 days (control) showed ~50% males (P < 0.01). Next, tilapia was cultured for 6 months in cistern and pond culture systems with 17α-methyltestosterone-treated diet (10 mg/kg) for three different durations: 0 days (control), 30 days (30-day-treated), and 180 days (throughout-treated). Fish in pond culture showed significantly higher (P < 0.05) final weight compared with tilapia in cistern culture (235.76, 156.82 g, respectively). Both 30-day-treated and throughout-treated fish showed significantly higher (P < 0.05) final weight, length, daily weight gain, specific growth rate, and muscle protein content compared with control fish. The androgen receptor β mRNA and protein expression levels in both 30-day-treated and throughout-treated fish were significantly higher (~twofolds, P < 0.05) compared with hormone-untreated control males. However, there was not much difference for all these parameters among the two hormone-treated groups. This higher growth probably results from an androgen-induced increased ‘androgen-androgen receptor’ mediated anabolic pathway. Serum testosterone concentration of 30-day-treated fish after 6 months was similar to that of control males (0.9 ng/ml). Moreover, culture of 17α-methyltestosterone-treated monosex tilapia was found beneficial than hormone-untreated mixed-sex tilapia culture for maintenance of natural fish diversity in indigenous water bodies.  相似文献   
102.
The effect of higher packing density and increased duration of transport on the survival and key metabolic enzymes of Labeo rohita fry was investigated. L. rohita fry (length 40 ± 5 mm, weight 0.60 ± 0.13 g) were packed in two different densities 40 and 80 g/l and sampled at 0, 12, 24, and 36 h after packing. Results showed that packing density and length of confinement severely affected the survival of the fry. The whole-body glucose level and the activities of the enzymes, lactate dehydrogenase (LDH), malate dehydrogenase (MDH), glucose-6-phosphatase (G6Pase), fructose-1, 6-bisphosphatase (FBPase), aspartate amino transferase (AST), alanine amino transferase (ALT), and adenosine triphosphatase (ATPase) assayed from the fish whole-body significantly (P < 0.05) increased due to increase in the length of the confinement. However, acetylcholine esterase (AchE) activity decreased significantly (P < 0.05) with increase in the length of confinement. Similarly, higher packing density also significantly (P < 0.05) increased the glucose level and activities of all these enzymes (except AchE). The results revealed that both higher packing density and increased transportation duration mobilize protein resources for glucose production via gluconeogenesis and subsequently activate the glycolysis pathway for energy. The rise in the ATPase activity indicates disruption of the osmoregulatory function and the role of this enzyme in ameliorating it. Overall results suggest that normally practiced packing density of 40 g/l is optimum up to 24-h duration for seed transportation.  相似文献   
103.
A minor flavonoid constituent of Limnophila rugosa has been isolated from its petrol extract and identified as 5,7-dihydroxy-8,3',5'-trimethoxyflavone (1).  相似文献   
104.
Summary Four barley strains viz. 1098–2, 1098–7, 1098–9 and 733–6, obtainedfrom the progeny of the crosses, Jyoti x Hyproly and Vijay x Hiproly which showed an increase in the grain protein content and an improvement in amino acid balance, were identified.  相似文献   
105.
Tropical Animal Health and Production - Variance and genetic parameters were estimated for growth and production traits of synthetic broiler female line (PB-2) using REML animal model to delineate...  相似文献   
106.
An experiment was conducted to study regrowth and yield of coriander influenced by nitrogen (N) with five different urea doses (0, 1.5, 2.0, 2.5, 3.0% by volume) as foliar spray. Spraying of urea has a significant impact on growth and yield in the second cut. Leaf emergence rate (LER) was higher during initial growth phase and then drastically reduced until first cutting, whereas the stem elongation rate (SER) recorded its peak value during 75-105 DAS. Impact of foliar spray was conspicuous during the later phase of regrowth with the treatment of 2.5% urea achieving the highest SER. Additional return due to spraying was positive up to a dose of 2.5% urea and decreased thereafter. Hence, the study indicated that a foliar spray of nitrogen (2.5% urea) may be beneficial for coriander leaf production under multicut system and the crop is sensitive to rainfall, phototemperature, and morning humidity.  相似文献   
107.
ABSTRACT

To observe the effects of deficiency and excess of copper (Cu) on rapeseed (Brassica napus L. cv ‘T44’), plants were raised in refined sand at variable levels of Cu (as copper sulfate): 0.01, 0.1, 0.5, 1, 10, 100, and 200 μM, representing a range from acute deficiency to excess. In rapeseed, excess Cu (200 μM) induced chlorosis on young leaves similar to iron (Fe) deficiency symptoms and appeared earlier (day 30) than symtoms of Cu deficiency (day 40). Foliar symptoms of Cu deficiency (0.01 μM) were initiated on young leaves as interveinal chlorosis, later leading to necrosis. The margins of the affected leaves curled inward and leaves hung down due to loss of turgor. The deficiency (< 1 μM Cu) and excess (100 and 200 μM Cu) of Cu lowered the biomass, pod, and seed yield, concentration of chlorophylls (a and b), Hill reaction activity, activity of catalase and polyphenol oxidase, and increased the activity of ribonuclease and acid phosphatase in leaves. The activity of peroxidase decreased and the concentration of copper in leaves (young and old) and seeds increased with an increase in Cu from low to excess. The accumulation of Cu was greater in old than in young leaves. The seed quality of rapeseed was poor both in deficiency (< 1 μM) and excess (> 1 μM) of Cu, which was reflected in reduction in size and number of pods and seeds, oil content, concentration of protein, carbohydrate fractions (sugars and starch), protein nitrogen (N), and methionine, and increased concentration of phenols and non-protein N in seeds. The values of Cu deficiency, threshold of deficiency, threshold of toxicity, and toxicity were, respectively, 3.8, 6.6, 32, and 54 μg Cu g?1 dry matter in young leaves and 2.2, 5.8, 20, and 28 μg Cu g?1 dry weight in seeds of rapeseed.  相似文献   
108.
To observe the effects of copper (Cu) deficiency on growth, metabolism, and reproductive yield of chickpea (Cicer arietinum L.) cv. ‘13.G-256’, plants were grown in refined sand at deficient (0.1 μM) and adequate Cu (1 μM), supplied as copper sulfate (CuSO4·5H2O). At d 35–40, at deficient Cu, the growth of plants were depressed and the young leaflets appeared reduced in size, chlorotic, with narrow pointed tips. The primary branches collapsed later, and secondary branches were stunted with reduced number of leaves. The flowering was disturbed, less flowers matured, as a consequence pods and seeds were reduced, malformed and low in productivity, which lowered biomass and economic yield and is accompanied by decrease in Cu concentration in leaves and seeds. The quality of seeds deteriorated at deficient Cu as the concentration of proteins, carbohydrates (sugars and starch), protein nitrogen were lowered, and phenols, non-protein nitrogen, increased. Whereas in leaves, the concentration of carbohydrates (sugars and starch), phenols, and non-protein nitrogen were elevated and protein nitrogen was reduced. Copper deficiency also alleviated the concentration of chlorophyll (a and b) in leaves. At deficient Cu, the activity of antioxidative enzyme viz. peroxidase along with that of acid phosphatase and ribonuclease increased in leaves, seeds and pod wall of chickpea.  相似文献   
109.
A study was conducted to evaluate the effect of feeding different metabolizable energy (ME) and crude protein (CP) levels on performance of Aseel chicken during 0 to 8?weeks of age (Juvenile phase). At 1?day old, 432 chicks were randomly distributed into nine groups. Each group had 48 chicks distributed into eight replicates with six birds in each. Maize-soybean meal-based diets with three ME levels (2,400, 2,600 and 2,800?kcal/kg) and three CP levels (16%, 18% and 20%) were fed to birds in a 3?×?3 factorial design. Different ME levels had significant effect on body weight gain (BWG), feed intake and feed conversion ratio (FCR). Birds fed diet with 2,400?kcal/kg ME had significantly lower BWG (P?相似文献   
110.
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