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141.
142.
Cage‐pond integration system is a new model for enhancing productivity of pond aquaculture system. A field trial was conducted using African catfish (Clarias gariepinus) and Nile tilapia (Oreochromis niloticus) in cages and carps in earthen ponds. There were four treatments replicated five times: (1) carps in ponds without cage, (2) tilapia at 30 fish m?3 in cage and carps in open pond, (3) catfish at 100 fish m?3 in cage and carps in open pond, (4) tilapia and catfish at 30 and 100 fish m?3, respectively, in separate cages and carps in open pond. The carps were stocked at 1 fish m?2. The cage occupied about 3% of the pond area. The caged tilapia and catfish were fed and the control ponds were fertilized. Results showed that the combined extrapolated net yield was significantly higher (P < 0.05) in the catfish, tilapia and carps integration system (9.4 ± 1.6 t ha?1 year?1) than in the carp polyculture (3.3 ± 0.7 t ha?1 year?1). The net return from the tilapia and carps (6860 US$ ha?1 year?1) and catfish, tilapia and carps integration systems (6668 US$ ha?1 year?1) was significantly higher than in the carp polyculture (1709 US$ ha?1 year?1) (P < 0.05). This experiment demonstrated that the cage‐pond integration of African catfish and Nile tilapia with carps is the best technology to increase production; whereas integration of tilapia and carp for profitability.  相似文献   
143.
The aim of this study was to provide a detailed anatomic atlas of the cranial abdomen by means of computed tomography (CT). Three mature dogs, all mixed breed males, were used. The dogs were sedated, anaesthetized and positioned in sternal recumbency. CT scans from the eighth thoracic vertebra to the fourth lumbar vertebra were performed using a third-generation equipment (TOSHIBA 600HQ scanner) with 1 cm slice thickness. CT-images of the cranial abdomen were taken with soft-tissue window (WL: −14, WW: 658) settings. Dogs were killed and vascular-injection technique was performed: red and blue latex filled the vascular system. Injected dogs were frozen in the same position as used for CT examination and sectioned with an electric bandsaw at 1-cm-thick intervals. The cuts matched as closely as possible to the CT-images. The anatomic sections were compared and studied with the corresponding CT-images, and clinically relevant abdominal anatomic structures were identified and labelled on the corresponding CT-images. The results of our study could be used as a reference for evaluating CT-images of the canine cranial abdomen with abdominal diseases.  相似文献   
144.
The present study was conducted to evaluate the effect of dietary supplementation of probiotic bacterium Bacillus licheniformis on the gut microbiota, growth and immune response in Macrobrachium rosenbergii juveniles (4.0 ± 0.02 g). Five isocaloric experimental diets supplemented with different concentrations of B. licheniformis, viz. Control (without probiotic supplementation), T1 (1.0 × 106 cfu g?1feed), T2 (1.0 × 107 cfu g?1feed), T3 (1.0 × 108 cfu g?1 feed) and T4 (1.0 × 109 cfu g?1 feed) were used for the experiment. After 60 days of feeding trial, the growth performance increases significantly in all the experimental groups compared with control, and highest weight gain, specific growth rate and lowest feed conversion ratio were recorded from T4 (P > 0.05). However, juvenile survival was not found to be significantly affected by probiotic supplementation (P > 0.05). The total bacterial count and Bacillus spp. count in the gut were significantly increased with concurrent decrease in pathogenic Aeromonas spp. and Pseudomonas spp. in all the experimental groups compared with control (P < 0.05). Compared with control, immune parameters were increased significantly in all the experimental groups (P < 0.05). Highest haemocyte count, phenol oxidase, superoxide dismutase and antibacterial activity in haemolymph were recorded from T4 (P < 0.05). When prawns were challenged with Vibrio alginolyticus, the cumulative mortality was significantly lower in T4 (P < 0.05). These results indicate that dietary supplementation of B. licheniformis can manipulate the gut microbiota and increase the growth and immune response of M. rosenbergii. In the present study, concentration response on the probiotic effect of B. licheniformis was observed which showed higher effects at a concentration of 1.0 × 109 cfu g?1 feed in the laboratory condition.  相似文献   
145.
Murraya koenigii (L.) Spreng. (Rutaceae) is characterized by a large chemical intraspecific variability among the land races. This fact makes it difficult to detect real changes occurring in their essential oil composition during annual cycle. Based on this, variations of essential oil yield and composition in two chemotypes (‘A’ and ‘B’) of M. koenigii were assessed in spring, summer, rainy, autumn and winter seasons under foot hill conditions of northern India. The essential oil yield ranged from 0.15% to 0.18% in chemotype ‘A’, while it varied from 0.12% to 0.14% in chemotype ‘B’. Essential oils of both chemotypes from different seasons were analysed by gas chromatography (GC-FID) and gas chromatography-mass spectrometry (GC-MS). A total of fifty-eight constituents representing 93.7-98.8% of chemotype ‘A’ and fifty-six constituents forming 96.1-98.7% of the total composition of chemotype ‘B’ were identified. Chemotype ‘A’ was characterized by higher percentages of α-pinene (34.6-41.9%), sabinene (26.1-36.1%), (E)-caryophyllene (2.4-5.4%) and terpinen-4-ol (1.5-5.3%), whereas chemotype ‘B’ was dominated by higher amount of α-pinene (52.7-65.3%), β-pinene (10.7-12.9%), (E)-caryophyllene (3.1-10.3%) and limonene (5.1-7.8%). Comparative results showed considerable variations in the essential oil composition of both chemotypes due to season of collection. Present study concluded that the M. koenigii leaves of desired quality may be obtained by selecting suitable chemotype and season.  相似文献   
146.
ABSTRACT

This study examined if, and how, comanagement is effective in controlling aquaculture industry in the municipalities of Anda and Bolinao in the province of Pangasinan, in the Philippines, the locations of two major production areas of milkfish (Chanos chanos) in the country. Institutional and community analyses conducted in these study sites revealed a unique hierarchy of resource users, as well as unique social and economic problems in aquaculture, distinct from those of capture fishery. It was also indicated that comanagement is seen as a solution for essential practices to be enforced practically and sustainably for the management of this industry. To improve aquaculture governance, it is desired that the comanagement scheme shall include not only the governments and fishers but also business operators who often have large capital and a high degree of power.  相似文献   
147.
Drought indices (DI) are an useful tool for assessing different sectarian droughts. Standardized Precipitation Index (SPI) has been used worldwide to assess/monitor the onset, active phase, cessation and severity of drought. Normalized Difference Vegetation Index (NDVI) provides a comprehensive vegetation dynamics, which directly linked with rainfall received in a particular region. Indo-Gangetic Region (IGR), providing employment and livelihood to tens of millions of rural families directly or indirectly and rice (Oryza sativa L.)-wheat (Triticum aestivum L.) (RW) system of the Indo-Gangetic Plains (IGP) contributes 80% of the total cereal production and is critical to food security of the region. This study tries to verify the applicability of water-vegetative indices viz., SPI, Rainfall Index (RI) and NDVI for drought assessment of rice-wheat system productivity over IGR-India. The relationship between monsoon rainfall and NDVI shows that at around 1100 mm rainfall, the NDVI reached saturation point and no further significant increase in NDVI with increase of rainfall is noticed. Even though, there was a positive correlation of seasonal monsoon rainfall and average NDVI, conflicting results are noticed between monthly distribution of rainfall and monthly anomaly of NDVI over IGR States. It is noticed that June dif NDVI (actual NDVI-mean NDVI) contributes more to rice productivity followed by July. However, the combined effect of June, July and August, explains 15% of the variation of Kharif Rice Productivity Index (KRPI). As far as wheat is concerned, statistically significant relation was found between Wheat Productivity Index (WPI) and anomaly NDVI during December-March. This explains 35% of the variability in WPI.  相似文献   
148.
This study was performed to determine the growth and survival patterns of the juvenile yellowleg shrimp Farfantepenaeus californiensis cohabiting with the green feather alga Caulerpa sertularioides over a range of temperatures (18, 22, 25, 28 and 32°C) found throughout the year in the Gulf of California. From an initial weight of 46 ± 10 mg, shrimp cohabiting with green feather algae increased in weight by an average of 0.57 (±0.07), 5.44 (±0.45), 6.36 (±0.37), 7.66 (±0.26) and 5.96 (±0.59) g at 18, 22, 25, 28 and 32°C, respectively, whereas shrimp grown without seaweed increased in weight by an average of 0.28 (±0.026), 2.66 (±0.24), 3.15 (±0.49), 4.00 (±0.67), and 3.54 (±0.09) g respectively. Statistically significant differences were observed for the growth rates of juvenile yellowleg shrimp in the presence of C. sertularioides and peak growth was observed at 28°C in experiments with macroalgae. No significant differences were observed for shrimp survival except at 32°C without macroalgae, where survival was lower. These results suggest a beneficial and growth‐promoting effect of cohabitation with live C. sertularioides on F. californiensis.  相似文献   
149.
Podophyllum hexandrum Royle (Syn. P. emodi Wale) a perennial rhizomatous herb found in alpine region distributed in the entire range of Himalayas from Ladakh to Sikkim at an altitude of 3000-4200 m asl is an preferred commercial source of Podophyllum lignans. It contains three times more Podophyllotoxin than the American species, Podophyllum peltatum. The present study was aimed to investigate variation of Podophyllum lignans contents based on six marker compounds viz. Podophyllotoxin; Deoxypodophyllotoxin; Picropodophyllotoxin; Podophyllotoxin β-d-glucopyanoside; Isopicropodophyllone; 4′-Demethyldeoxypodophyllotoxin, β-d-lucopyanoside, in P. hexandrum population growing at three locations. Further, ontogenetic and morphogenetic variations of Podophyllum lignan contents were studied to investigate dynamics of accumulation of these compounds. Representative collections from three locations viz., Panikhar, Padam and Tangoli located in Trans Himalayan semi-desert region of Zanskar valley were harvested at three stages (dormancy, active growth and maturity). Plants were dissected into root, rhizome and rhizome-buds, dried separately and assayed for Podophyllum lignan contents by high performance liquid chromatography.  相似文献   
150.
A 60 days study was conducted to evaluate the efficacy of water extract of Ocimum sanctum Linn. leaf on the immune response and disease resistance of Labeo rohita fingerlings against the Aeromonas hydrophila infection. Ocimum sanctum extract was incorporated in the diets (at 0.0%, 0.05%, 0.1%, 0.2%, 0.5% and 1%) of Labeo rohita, rohu fingerlings (6.6 ± 0.013 g). After 42 days blood, plasma and serum were sampled to determine super oxide anion production, lysozyme activity, total immunoglobulin in plasma, blood glucose, serum total protein, albumin, globulin, albumin:globulin ratio, WBC, RBC, haemoglobin content. Fish were challenged with A. hydrophila after 42 days and mortalities were recorded over 18 days post infection. The results demonstrate enhanced super oxide anion production, lysozyme activity, total immunoglobulin in plasma, serum total protein, globulin, total RBC counts, total WBC counts and haemoglobin content (P < 0.05) in treatments group compared with control group. Dietary O. sanctum extracts of 0.2% showed significantly (P < 0.05) higher protection relative percentage survival (RPS 40.00 ± 5.773%) against A. hydrophila infection than control. These results indicate that O. sanctum leaf extract stimulates the immunity and makes L. rohita more resistant to bacterial infection (A. hydrophila).  相似文献   
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