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21.
A 70‐day growth trail was conducted to investigate the effects of inclusion of high levels of meat and bone meal (MBM) and protein concentrate (PC) on growth, digestibility and economic performances of climbing perch, Anabas testudineus. Four isonitrogenous diets were formulated by lowering the level of dietary fishmeal protein at 0 (D1, control), 70 (D2), 85 (D3) and 100% (D4) with a mixture of MBM and PC protein (1:1). Triplicate groups of 300 fish (mean weight of 0.80 g) stocked in each 40 m2 pond and fed the respective test diets. A digestibility trial was conducted after the growth trial in indoor glass aquarium. The result showed that growth parameters were significantly decreased (P < 0.05) with fishmeal replacement levels. However, significant differences were not found in feed conversion ratio and survival of fish. No difference was also found in protein efficiency ratio among D1, D2 and D3. Similar to growth parameters, total fish production was highest in D1, intermediate in D2 and D3; and lowest in D4. Apparent digestibility coefficients of dry matter, protein and lipid were highest (P < 0.05) in D1 and lowest in D4. The economic analysis revealed that the benefit cost ratio was ranked by D3 (1.81), D2 (1.71), D1 (1.66) and D4 (1.46) respectively. Upon considering the overall performances and unavailability of finite protein sources, it can be concluded that 70–85% fishmeal could be replaced with a mixture of MBM and PC (1:1) in practical diets for climbing perch.  相似文献   
22.
ABSTRACT:   To explore the potential utility of underutilized fish in the fish sauce industry, fish sauces were prepared from both raw and heat-induced meat of Japanese anchovy Engraulis japonica and rabbit fish Siganus fuscescens using wheat malt, and their quality aspects and sensory properties were assessed. Proximate composition of the fish meat represents protein as the major component (16.0–17.8%), other than moisture. Analyses of free amino acids, peptides including oligopeptides, and organic acids contents in fish sauces revealed suitability of both raw and heat-induced meat of the selected species in commercial fish sauce production. The variations in taste of raw meat fish sauces were species-specific, but the taste of fish sauces from heat-induced meat were similar.  相似文献   
23.
In the present study, a potential Lactobacilli probiotics were isolated from Japanese eels (Anguilla japonica) and characterized and evaluated for their possible use in eel farming. Sixteen Lactobacilli were isolated from intestines of Japanese eels, using selective media. The lactobacilli strains (represented as PL1 to PL16) were screened by their ability to produce digestive enzyme. Among these, three strains (PL11, PL13 and PL16) producing four digestive enzymes (amylase, cellulase, protease and phytase) simultaneously were characterized further using API ZYM kit. From these, PL11 (Lactobacillu (L.) pentosus) was identified as potential probiotics candidate producing 15 enzymes among 20 tested. Further examination of biological activities of PL11 revealed tolerance against pH, artificial bile juice and antibacterial activity against several fish pathogenic bacteria. The in vitro competitive exclusion assay also revealed 88.4% reduction in adhesion of fish pathogen (Edwardsiella tarda) by PL11 to host intestinal mucus. In vitro incubation of Japanese eel foregut with Baclight‐labelled PL11 showed colonization of the enterocyte surface by confocal and scanning electron microscopy. In summary, PL11 isolated from eels could serve as a potential probiotics with acid and bile tolerance, production of digestive enzymes, antibacterial activity and inhibition of fish pathogen adhesion to intestinal mucus.  相似文献   
24.
Susceptibility to acephate, methomyl, and permethrin was determined with laboratory bioassays for adults of greenhouse whitefly, Trialeurodes vaporariorum Westwood, from 12 to 14 sites in Hawaii. Comparisons at LC50 showed up to 42-fold resistance to acephate, 36-fold resistance to methomyl, and 8-fold resistance to permethrin. Higher levels of resistance to acephate and methomyl than to permethrin are consistent with greater use of organophosphates and carbamates than pyrethroids by growers. Insecticide use varied from 1 to 98 insecticide sprays per site per season. Significant positive associations between LC50 for each insecticide and frequency of application of the same insecticide were found across sites. This finding suggests that local variation in insecticide use was an important cause of variation in susceptibility.  相似文献   
25.
Microorganisms play a major role in the degradation and detoxification of most soilapplied pesticides. Any interference with soil microbial activity may affect the persistence as well as the effectiveness of the pesticide. The objective of this study was to investigate the effect of granulated superphosphate fertilizers on terbutryn (2-(tert-butylamino)-4-(ethylamino)-6-(methylthio)-l,3,5-triazine) degradation and on its herbicidal activity. Concentrations exceeding 1% of superphosphate in the soil slowed down terbutryn degradation; a concentration of 3% completely inhibited terbutryn degradation for nearly 60 days. When terbutryn was impregnated on the surface of superphosphate granules, the concentration of the fertilizer that inhibited terbutryn degradation was reduced from 3% to 0.1%. Bioassays with mustard seedlings confirmed the results obtained by chemical analysis of terbutryn. The decrease in the rate of terbutryn degradation was not specific to superphosphate. The inhibition of degradation could be attributed mainly to the concentration of the salt in the soil solution, expressed as electrical conductivity values, and not to the pH of the soil or to the type of the salt. Terbutryn was found to be quite stable on the surface of the superphosphate granule. At the concentrations tested, superphosphate did not affect root growth. The optimal weight of the impregnated granule for extending terbutryn activity was 125 mg, containing 0.2% terbutryn. A greenhouse experiment confirmed the findings that fertilizers could serve as potential inhibitors of terbutryn degradation.  相似文献   
26.
Mandibular pyogranulomatous osteomyelitis was diagnosed in a female Sannen goat. The doe presented for difficulty prehending and chewing food. The left mandible was swollen and firm on palpation. Radiographs revealed changes consistent with osteomyelitis of the affected mandible. Arcanobacterium pyogenes was isolated from aspirates of swollen mandible. Despite antimicrobial therapy, the goat died. Histopathological findings were consistent with pyogranulomatous disease of the affected mandible. The histopathological findings were similar to those reported for actinomycosis, caused by Actinomyces bovis. Mandibular osteomyelitis is a common condition in cattle and very rare in goat.  相似文献   
27.
To compare the genetic susceptibility of elk (Cervus elaphus nelsoni) with various alleles of the PRNP gene, which encodes the normal cellular prion protein, to chronic wasting disease (CWD), eight 8-month-old elk calves of 3 genotypes (2 132MM, 2 132LM, and 4 132LL) were orally dosed with CWD-infected brain material from elk. During postinoculation (PI) month 23, both 132MM elk had lost appetite, developed clinical signs of weight loss and central nervous system (CNS) dysfunction, and were euthanized. Two other elk (both 132LM) developed similar clinical signs of disease and were euthanized during PI month 40. All 4 affected elk had microscopic lesions of spongiform encephalopathy (SE), and PrPres, the disease-associated form of the prion protein, was detected in their CNS and lymphoid tissues by use of immunohistochemical (IHC) and Western blot (WB) techniques. These findings indicate that elk with MM and LM at codon 132 are susceptible to orally inoculated CWD. All 4 LL elk are alive at PI year 4 and are clinically normal, which suggests that 132LL elk may have reduced susceptibility to oral infection with CWD-infected material or may have prolonged incubation time.  相似文献   
28.
集约化商品肉鸡生产企业的目标是每只入舍母鸡能够生产出最大数量的可孵化种蛋和最多的高质量雏鸡。在适当的饲养管理条件下,一只母鸡产蛋可超过180个,鸡肉产量达到270kg。这些生产数据在鸡只之间存在着非常大的差距,其原因可追溯至种蛋的收集标准、储存条件和孵化条件。在坚持种蛋选择与分级的基础上进行常规性的饲养管理,生产企业获得最大收益的目标不难实现。  相似文献   
29.
利用随机区组试验评估了孟加拉国吉大港大学苗圃内的银合欢落叶对森林作物种白格、黄金檀和农田作物种长豇豆、鹰嘴豆和木豆的他感作用。结果表明,凋落叶诱导抑制作物的萌发和生长,该抑制作用依赖于萃取物浓度、凋落物及受体物种类型。萃取物浓度越高则他感作用越强。受体植物的生长响应随应用的凋落叶而变化。低浓度(10g·m-2)凋落叶对农田作物嫩芽生长有促进作用,而其他浓度的凋落叶则呈现明显的抑制作用,施用的凋落叶浓度越大抑制作用也越大。但是不同处理所表现出的抑制趋势并不均一,根系生长受到的影响大于嫩芽。图3表4参34。  相似文献   
30.
The petroleum ether and ethanol extracts of Vitex trifolia leaves exhibited moderate inhibiting activity against both gram-positive and gram-negative bacteria.  相似文献   
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