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31.
Pomegranate fruit is an important source of potentially healthy bioactive compounds and mineral nutrients. Changes in total phenolic compound, concentrations, and levels of macronutrients (P, K, N, Mg, Ca and Na) and micronutrients (Zn, Cu, Mn, Fe and B) in arils and peel of pomegranate fruit were recorded from 10 days after full bloom until harvest. Total phenolics levels increased at early stage of growth both in peel and arils of fruit, but thereafter generally decreased during maturation and reached to 3.70 and 50.22 mg g−1 of dry weight in arils and peel, respectively, at harvest. The amount of total phenolics in peel was markedly higher than arils of pomegranate fruit. The concentration of most elements in arils and peel decreased during fruit growth and development. At harvest the relative order of concentration of macronutrients both in arils and peel was K > N > Ca > P > Mg > Na. The concentration of most micronutrients was greater in the arils than in the peel especially in early season. The relative order of concentration of micronutrients in arils was B > Fe > Zn > Cu > Mn. The accumulation of all the macro- and microelement within the fruit also increased during fruit growth and development. These results provide important data on total phenolics and macro- and micronutrient changes during fruit growth and development, emphasizing that pomegranate fruit can be a good source of bioactive compounds and minerals. 相似文献
32.
On the basis of various industrial importances of hydroxyl fatty acids we have investigated Sesbania aculeata seed oil. The most interesting finding is the presence of a hydroxyolefinic fatty acid (9.24%) along with other usual fatty acids such as lauric (2.51%), myristic (0.37%), palmitic (10.94%), palmitoleic (3.54%), stearic (4.02%), oleic (17.10%), linoleic (45.92%), linolenic (5.29%), arachidic (0.03%) and behenic (1.04%). The structure of this hydroxy fatty acid was established on the basis of spectral data (IR, 1H NMR, 13C NMR, MS) and chemical (catalytic hydrogenation, oxidative degradation) methods as (Z)-12-hydroxyoctadec-9-enoic (ricinoleic) acid. 相似文献
33.
Abdul Qayyum Siddiqui Yousef S. Al-Hafedh Ahmed H. Al-Harbi Seikh A. Ali 《Journal of the World Aquaculture Society》1997,28(1):106-112
Abstract This study was conducted to evaluate the effects of stocking density and monosex culture on growth, survival, yield and feed conversion ratio of freshwater prawn Macrobrachium rosenbergii in concrete tanks. Juvenile prawns with an average weight of 1.8 g were stocked into triplicate tanks at densities of 5, 10, 15 and 20 prawns/m2 , grown for 168 d and fed a 34% tilapia diet. Stocking density had significant effect on prawns. Final mean body weight decreased with the increasing density, being highest at 5 prawns/m2 (29.6 9). and lowest at 20 prawns/m2 (17.4 g). Total yield increased from 135 g/m2 (1,350 kg/ha) at a density of 5 prawns/m2 to 261 g/m2 (2,610 kg/ha) at density 15/mz to 245 g/m2 (2,450 kg/ha) at 20/mz . Feed conversion ratios were high and ranged from 3.7 (5 prawns/m2 ) to 5.6 (20 prawns/m2 ).
In monosex culture of freshwater prawns stocked in triplicate tanks at a density of 5 prawns/m2 for 112 d, the all-male population had the best growth performance and feed conversion ratio, followed by the mixed-sex and all-female populations. The all-male population had 99% marketable prawns (>20 g) with an average yield of 159 g/m2 (1,590 kg/ha); the mixed-sex population had 90% marketable prawns and the yield was 135 g/mz (1,350 kg/ha); and the all-female population had 75% marketable prawns with an average yield of 108 g/m2 (1,080 kgha). 相似文献
In monosex culture of freshwater prawns stocked in triplicate tanks at a density of 5 prawns/m
34.
在阿富汗首都喀布尔的西南部,在飞扬的尘土和战后满目疮痍的城市里,幸运地保留着一块绿树葱茏的清凉绿洲,那就是喀布尔动物园。然而,动物园里并非一派安宁平和,那儿的动物对它们的生存状况极其愤怒,管理员们同样也很生气。 相似文献
35.
K. G. Macdicken K. Hairiah A. Otsamo B. Duguma N. M. Majid 《Agroforestry Systems》1996,36(1-3):131-149
Imperata is shade-intolerant, although little is known of the relative roles of competition for light, water and nutrients in suppressing its growth. Shading of Imperata results in reduced carbohydrate storage, reduced rhizome and tuber-bulb production, reduced shoot dry weight, increased susceptibility to competition, increased susceptibility to herbicides and decreased vigor/regeneration. Herbaceous cover crops in the genera Calapogonium, Crotoleria, Mucuna and Pueraria have been shown to effectively suppress Imperata growth and can be used to prevent and in some cases eradicate Imperata. Tree fallows with fast-growing species such as Sesbania sesban, Acacia nilotica and Leucaena leucocephala can improve soil physical and chemical properties and suppress weed growth. Forest plantations have been successfully used, particularly with the use of moderate to high tillage, weeding and fertilizer inputs to suppress Imperata growth. These plantations produce marketable wood and reclaim the site for other uses. Additional research is needed to evaluate the specific nature of competition and allelopathic effects from Imperata. Continued evaluation of tree species and provenances for Imperata suppression, forms of tillage after woody fallow crops and the constraints to adoption of cover crops and trees as Imperata control measures are also needed. 相似文献
36.
37.
Majid Gholami-Ahangaran Noosha Zia-Jahromi Abdolrasul Namjoo 《Tropical animal health and production》2014,46(2):349-353
In recent years, some outbreaks of skin lesions suspected to be avian pox were observed in the backyard poultry in different parts of western areas in Iran. Consequently, 328 backyard poultries with suspected signs of avian pox virus infection were sampled. All birds showed nodular lesions on unfeathered head skin and/or fibronecrotic lesions on mucus membrane of the oral cavity and upper respiratory tract. For histopathological analysis, the sections of tissue samples from cutaneous lesions of examined birds were stained with H&E method. For PCR, after DNA extraction a 578-bp fragment of avian pox virus from 4b core protein gene was amplified. Results showed 217 and 265 out of 328 (66.1 and 80.7 %, respectively) samples were positive for avian pox virus on histopathological and PCR examination, respectively. In this study, the samples that had intracytoplasmic inclusion bodies on pathologic examination were PCR positive. This study revealed that PCR is a valuable tool for identification of an avian pox virus and that the frequency of pox infection in backyard poultry in western areas of Iran is high. 相似文献
38.
39.
M Shahab Uddin S M Shamsul Rahman M Ekram Azim M Abdul Wahab M C Jarc Verdegem & Johan A J Verreth 《Aquaculture Research》2007,38(16):1759-1769
The present research investigated the effect of stocking density on pond (75 m2, depth 1.2 m) production of Nile tilapia (Oreochromis niloticus) and freshwater prawn (Macrobrachium rosenbergii) stocked at a fixed 3:1 tilapia:prawn ratio. Three stocking densities were tried in triplicate: 20 000 ha−1 (treatment TP‐20), 30 000 ha−1 (TP‐30) and 40 000 ha−1 (TP‐40). The ponds were provided with bamboo as substrate for periphyton development. Bamboo poles (mean diameter 5.5 cm and 5.0 poles m−2) were posted vertically into pond bottoms, resulting in 60% additional substrate area in each pond. On average, 43 genera of algae and 17 genera of zooplankton were identified from pond water, whereas 42 genera of algae and six genera of microfauna were attached to bamboo substrates. No differences were observed between treatments in the ash‐free dry matter (AFDM), chlorophyll a and phaeophytin a content of periphyton (P>0.05). Survival of tilapia and prawn and individual weight gain of tilapia were lower (P<0.05) in treatment TP‐40. The net yields were higher (P<0.05) in treatments TP‐30 (2209 and 163 kg ha−1 105 day−1 of tilapia and prawn respectively) and TP‐40 (2162 and 141 kg ha−1 of tilapia and prawn respectively) than in treatment TP‐20 (1505 and 136 kg ha−1 of tilapia and prawn respectively). The net tilapia yields were quadratic correlated (R2=0.92) with fish stocking density. The cost–benefit analysis shows that the net profit margin was highest in treatment TP‐30 (69%), followed by TP‐20 (50%) and TP‐40 (44%). 相似文献
40.
Oliver Schneider Abdul K Amirkolaie Jordi Vera-Cartas Ep H Eding Johan W Schrama & Johan A J Verreth 《Aquaculture Research》2004,35(14):1370-1379
This study shows that alternatives for fishmeal in a fish diet affect not only fish growth but also faeces stability and nitrogen (N) and phosphorus (P) waste production. Wheat gluten diet (WGD), soybean meal extract diet (SBE), soybean meal diet (SBM), duckweed diet (DWD) and single‐cell protein diet (SCP) were evaluated as a fishmeal replacement on a 15% weight weight?1 basis in tilapia diets. Fishmeal replacement affected dry matter (dm), protein, ash and P digestibility significantly. Faeces recovery (6.8–11.2%) was not significantly affected, although the amount of non‐recovered faeces and total faeces showed significant differences. Duckweed diet and SCP resulted in the largest amounts of non‐recovered and total faeces (199–210, 224–225 g dm kg?1 feed dm). Compared with fishmeal diet (FMD), the WGD and SBE resulted in similar growth, but higher non‐faecal N losses (471–495 vs. 416 g N kg?1 N). Soybean meal diet, DWD and SCP resulted in lower growth but less non‐faecal loss (409–450 g N kg?1 N). The DWD and FMD had the highest N retention (480 g N kg?1 N) compared with the other diets (431–451 g N kg?1 N). Carbon retention, faecal and non‐faecal losses and P retention were similar for all diets (302–358, 142–176 and 489–523g C kg?1 C, 606–704 g P kg?1 P). Phosphorus faecal loss was lower for all diets (329–381 g P kg?1 P) than for the FMD (401 g P kg?1 P). 相似文献