BACKGROUND: Intensive aquaculture and commercialization production are believed to be needed for improving fish health status and probiotics are candidates to achieve this goal. OBJECTIVES: In this study, we utilized Lactobacillus plantarum and Lactobacillus pentosus as autochthonous food supplementation for biochemical investigation in rainbow trout. METHODS: In the current study, 240 juvenile rainbow trout with an average weight of 15 ± 2 g were randomly divided into four groups with three replications. Group 1, 2, and 3 were fed with 108 CFU/g of L. plantarum, L. pentosus, and the combination of these two probiotics, respectively. The control group was fed with the normal diet, for 60 days (2 % of body weight, 3times per day). Samples were taken at days 0 and 60 and biochemical parameters and hepatic enzymes activity were then investigated. RESULTS: Most biochemical factors had positive changes in the fish fed with probiotics, particularly in L. plantarum group (p < 0.05). Furthermore, the results exhibited a significant decrease in ALP level in the probiotic groups, particularly in L. pentosus group (p < 0.05). Meanwhile, AST enzyme activity in plantarum+pentosus group was higher than that in the other groups (p < 0.05). CONCLUSIONS: The present results indicated the effectiveness of food supplementation with probiotics in fish diet with the preference of probiotic to improve the biochemical factors and hepatic enzymes activity of rainbow trout, Oncorhynchus mykiss.

The experiment was set to determine the effects of long-term (55-day) use of three commercial prebiotics including Saccharomyces cerevisiae–derived β-glucans and one including inulin on juvenile vimba (Vimba vimba) reared intensively under controlled conditions.

In this study 87 fish feed samples were randomly collected from feed mills and fish farming establishments from 14 provinces in Turkey to determine the occurrence of total aflatoxin (AF) and total fumonisin contamination. The quantitative analysis of total AF and total fumonisin of the samples was carried out using commercial kits. The samples were analysed by microplate reader. Total AF residues were found in 86 (98.85%) of 87 analyzed samples. The avarage value for total AF (AFB1, AFB2, AFG1, AFG2) in positive samples was found as 8.776±4.178 µg/kg ranged from 1.023-17.566 µg/kg, and these values were found to be less than the recommended level 20 ppb (Food Drug Administration). Total fumonisin (B1, B2, B3) residues were found in 49 (56.98%) of 86 samples analysed. The avarage value for total fumonisin in positive samples was found as 0.3028±0.2584 mg/kg ranged from 0.0107-0.9278 mg/kg. These values were below the tolerable limit of 10 ppm for fumonisin (B1, B2) announced by Ministry of Agriculture and Forestry in Turkey. It was suggested that although mycotoxin residues were detected in the collected feeds, these values remained below the tolerable values.

In the world, aquaculture is seen as the fastest growing and developing food production sector and however, in the near future, it is estimatedthat the rates of fisheries and aquaculture will be equalized. In 2015, the fisheries production of the world amounted to 170,345,641 tons (fisheries;93,704,616 tons and aquaculture; 76,641,025 tons) according to the FAO records.The aquaculture in Turkey started in 1970s and its rate in total fisheries production has rapidly increased as of 2000. In our country, the amountof aquaculture, which was 79,943 tons in 2003, reached 253,395 tons in 2016. The aquaculture rate in the total production of our country hasincreased by more than 310%. As one of the most important reasons for this rate increase, it is seen to be providing some support policies withvarious incentive systems by the government for support and encourage the aquaculture in country.Directly product support for aquaculture farmers was started in 2003. According to the total capacity of the farms, total product and fry supportswere provided. In 2008, the total capacity supported was limited to 2000 tons/year. However, in 2012, different tonnage application (whole unitprice to 250 tons/year and ½ unit price from 251 to 500 tons/year) were brought to the total product support and the fry support was removed.At the same time, the processed product support was brought at the rate of twice the amount specified in the invoices of the total product. In thepresent, the support system is still continuing.The types of product support, prices, supported capacities and the expense criteria are applied annually by issuing the “Aquaculture SupportCommuniqués” in the Official Gazette.

Lactococcus garvieae is a Gram-positive bacterium that causes mortalities in freshwater and marine fish worldwide and therefore results in severe economic losses in the aquaculture industry. Apart from the apparent integral role of the exopolysaccharide (EPS) capsule in pathogenesis, factors associated with virulence of this bacterium are poorly understood. However, recent studies have indicated that the ability of L. garvieae to cause disease does not depend on the presence of the EPS capsule. Lack of knowledge of virulence factors, pathogenesis and serology of L. garvieae is an impediment to the development of effective typing methods and control measures. This study, therefore, aimed to detect the presence of EPS capsules and other putative virulence factors in South African L. garvieae fish pathogenic isolates and a non-virulent isolate, and to identify possible candidates for subunit vaccine development. No indication of the presence of the EPS capsule was detected by negative staining or amplification of the EPS biosynthesis gene cluster in the virulent isolates or the avirulent strain, discrediting the notion that the EPS capsule is the sole determinant of virulence. However, a set of putative virulence factor genes was detected in all isolates, and candidates for subunit vaccine development (enolase, lactate dehydrogenase phosphoenolpyruvate-protein phosphotransferase) were identified by identification of extracellular proteins of virulent strains.

This study describes the macroscopic and microscopic lesions in farmed rainbow trout (Oncorhynchus mykiss) naturally infected with genetically identified Aeromonas salmonicida, A. hydrophila, and A. veronii species. The genus Aeromonas includes bacteria that naturally inhabit both waterways and organisms. At least 27 Aeromonas species have been identified to date, some of which can cause significant economic losses in aquaculture. As up to 68.8% of Aeromonas isolates may be misidentified in routine biochemical and phenotypic tests, however, reported cases of Aeromonas infection in fish may be wrongly identified. Our findings confirmed that the 3 Aeromonas species studied are associated with septicemia and dermal lesions in rainbow trout.

Objective: The study was carried out to investigate the use and impact of veterinary drugs, anti¬microbials, and supplements in commercial aquaculture for fish health management measures in three selected areas of Mymensingh, Bangladesh. Materials and Methods: Data collection was conducted through questionnaire interviews with owners of 50 fish farms and 25 drug shop owners from Trishal, Fulpur, Tarakanda, and Sadar Upazila of Mymensingh district. Results: A total of 15 trade-named veterinary antibiotics and six categories of other compounds were identified in this study. Antibiotics were found as the most used veterinary drugs (80.85%), followed by disinfectants, nutritional supplements, saline, ammonia removal agents, probiotics, and pesticides. These veterinary compounds performances for fish health management were found to vary (10%60%) significantly. Conclusion: This studys findings urge the necessity to produce and approve effective aqua drugs and treatments to ensure farmed fish and public health. [J Adv Vet Anim Res 2021; 8(1.000): 36-43]

Creation of effective and easy-to-replicate in laboratory conditions culture medium for isolation of salmonella out of water, which could make it possible to increase the safety, authenticity and efficiency of bacteriological study of aquatic medium objects, was realized in the conditions of the Republic of Belarus. In course of the numorous preliminary experiments there was developed an enrichment medium containing the following: nutrient yeast (5 g/l); potassium phosphate monosubstituted (8,6 g/l); sodium hydrate (1,4 g/l); 0,1% brilliant green solution (5 cm3/l); 0,01% solution of crystal violet (10 cm3/l); distilled water (1 l). The analyzed medium was estimated in accordance with the following propertiesd: medium sensitivity; efficiency; inhibition of bacteria growing. Research result showed that the experimental medium was more sensitive in comparison with the selenite one. Studying of the efficiency of the compared media showed that accumulation of test strains of S. enteritidis on the experimental medium was in 10E4 times higher, S. typhi – in 10E3; S. typhiniurium, S. anatum was in 10 times higher than at selenite media. The experimental studies proved that the experimental culture medium for salmonella isolation out of city water and surface water was more sensitive and easier to use than the selenite medium

In the article concept and essence of aquaponic systems for production of ecologically clean agricultural production without waste technologies is set forth. A degree of a level of studies of the given рroblem in the countries of the Europe, America, Australia and other countries is set forth too. The expediency of application of similar systems for fuller use of power resources of plants for production of heat of the electric power, an opportunity of production of agricultural production in urban conditions and on the limited ground areas is proved