Estimates of Microbial Populations Involved in the N Cycle and their Activity in Water and Sediments of Fish Farming Ponds under Mono and Polyculture Systems in India

1983 ◽  
Vol 68 (4) ◽  
pp. 581-590 ◽  
Author(s):  
B. B. Jana ◽  
S. K. Roy
2018 ◽  
Vol 8 (2) ◽  
pp. 354-364
Author(s):  
A. N. Irkitova ◽  
A. V. Grebenshchikova ◽  
A. V. Matsyura

<p>An important link in solving the problem of healthy food is the intensification of the livestock, poultry and fish farming, which is possible only in the adoption and rigorous implementation of the concept of rational feeding of animals. In the implementation of this concept required is the application of probiotic preparations. Currently, there is an increased interest in spore probiotics. In many ways, this can be explained by the fact that they use no vegetative forms of the bacilli and their spores. This property provides spore probiotics a number of advantages: they are not whimsical, easily could be selected, cultivated, and dried. Moreover, they are resistant to various factors and could remain viable during a long period. One of the most famous spore microorganisms, which are widely used in agriculture, is <em>Bacillus subtilis</em>. Among the requirements imposed to probiotic microorganisms is mandatory – antagonistic activity to pathogenic and conditional-pathogenic microflora. The article presents the results of the analysis of antagonistic activity of collection strains of <em>B. subtilis</em>, and strains isolated from commercial preparations. We studied the antagonistic activity on agar and liquid nutrient medias to trigger different antagonism mechanisms of <em>B. subtilis</em>. On agar media, we applied three diffusion methods: perpendicular bands, agar blocks, agar wells. We also applied the method of co-incubating the test culture (<em>Escherichia coli</em>) and the antagonist (or its supernatant) in the nutrient broth. Our results demonstrated that all our explored strains of <em>B. subtilis</em> have antimicrobial activity against a wild strain of <em>E. coli</em>, but to varying degrees. We identified strains of <em>B. subtilis</em> with the highest antagonistic effect that can be recommended for inclusion in microbial preparations for agriculture.</p><p><em><br /></em><em></em></p>


Author(s):  
Ekaterina Grinberg

In two parts of the article, more than 70 errors and violations of the Biotechnics of artificial breeding of Pacific salmon in salmon hatcheries are collected and summarized, which lead to an immediate or delayed deterioration of the quality of reared fry and a decrease in their survival rate. Deviations from the biological basis of fish farming are shown and possible consequences of such errors or violations are predicted. In the first part of the article (#7,2020) there were General errors (throughout the entire fish-breeding process), as well as violations of Biotechnics during the work with producers, collecting eggs and preparing them for incubation, in the second part-violations of Biotechnics during the incubation of eggs, holding pre-larvae, rearing and release of young. Their correction, prevention or minimization of consequences will significantly improve the quality of sexual products and offspring from producers, increase the linear and weight gain of juveniles during rearing, improve the coefficient of feed payment, reduce the time of rearing, improve the epizootic situation by developing immunity in fry and mobilizing other protective reactions of their body, significantly reduce waste at all stages of the production process, increasing survival by 10–15%. In conclusion, it is noted that the first and most important condition for an efficient salmon hatchery is the creation of optimal environmental conditions at each stage of the production process. The second condition is strict compliance with the Biotechnics of artificial salmon breeding and the complex of veterinary and sanitary, fish-breeding and meliorative and therapeutic and preventive measures. The third is the availability of competent specialists who regularly improve their skills in accredited Universities to implement, control and manage the first two conditions.


Author(s):  
Z. Bolatbekova ◽  
S. Assylbekova ◽  
B. Kulatayev ◽  
S. Koishybayeva ◽  
N. Bulavina

The aryicle presents the results of a comparative study of the biochemical composition of earthworms of dendrobene and prospector rocks, the peculiarities of their cultivation and their use for feeding when growing juvenile tilapia and clary catfish. The experience of cultivating earthworms of two breeds using the improved methods of foreign authors is described. The results of a study of the biochemical composition of cultivated objects that determine their nutritional value for feeding fish are presented. The fish-breeding and biological indicators of juvenile tilapia and clary catfish, obtained during the cultivation of dendrobene and prospector in fish farming in the Almaty region (VI fish-breeding zone) during worm feeding, are analyzed. A comprehensive analysis of the studied indicators made it possible to assign a certain rating place to each worm breed in relation to its use as fish feed.


2019 ◽  
Vol 10 (4) ◽  
Author(s):  
Arnar Bjarnason ◽  
Soffia Karen Magnúsdóttir

2015 ◽  
pp. 692-696
Author(s):  
Remi Aubry ◽  
Laurence Gasnot

A study was carried out in six beet sugar factories in France during the 2012/13 sugar campaign. The objective was to assess the optimal dosage of formaldehyde solutions at specific process stages and in different existing factory set-ups in order to obtain the desired effect on microbial populations, without interference with the quality of the products. In addition harmlessness regarding consumer health was to be demonstrated. A series of experiments was conducted resulting in new data allowing refreshment of common knowledge and references existing regarding the use of formaldehyde solutions in the sugar industry. The effectiveness and convenience for controlling microbiological activity in beet sugar manufacture was assessed. Formaldehyde reduces sugar losses and protects in-process products without harming their further use, such as for ethanol production.


2017 ◽  
Vol 17 (1) ◽  
pp. 69-77
Author(s):  
Tu Lijun ◽  
Sun Hanju ◽  
He Shudong ◽  
Zhu Yongsheng ◽  
Yu Ming ◽  
...  

The aim of this study was to investigate epigallocatechin gallate (EGCG) prebiotics activities systematically which was reported as a bioactive substance. Therefore, EGCG was separated by water extraction, resin purification and prep-HPLC. Then the production of EGCG was confirmed by HPLC and mass spectrometry (MS) analysis and its purify was 97.23%. EGCG extractive and green tea extract (GTE) were further incubated with Bifidobacterium infantis, B. adolescentis, B. bifidum and Lactobacillus acidophilus to study its effect on microbial populations and medium pH. Finally, Escherichia coli, Salmonella, Staphylococcus aureus and Candida albicans were employed as pathogenic bacteria to explore the antimicrobial activity of EGCG and GTE. The results demonstrated that EGCG extractive could be beneficial for the proliferation of Bifidobacterium and L. acidophilus and also inhibit some pathogenic bacteria. In conclusion, both EGCG extractive and GTE had prebiotics activities and the effects of EGCG extractive were superior to those of GTE.


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