Use of antioxidants and time of cold storage: effects over viability parameters and enzymatic levels in semen of rainbow trout (Oncorhynchus mykiss, Walbaum, 1792) / Uso de antioxidantes e tempo de armazenamento a frio: efeitos sobre parâmetros de viabilidade e níveis enzimáticos no sêmen da truta arco-íris (Oncorhynchus mykiss, Walbaum, 1792)

The cold storage of milt implies potentials alterations in its quality because the storage generates as main process, free radicals that produce spermatozoa membrane lipids damage with the consequent motility and fertilising capacity disruptions. To decrease the damage generated by free radicals the cells have antioxidant defences (proteins, enzymes, and low molecular weight substances). The objective of the present study evaluated the time storage effect and different antioxidants prepared in spermatic diluents on sperm viability of O. mykiss milt stored at 4°C. The two-way ANOVA denoted that the time storage and antioxidant influence have significant effects separated or combined on viability parameters (sperm motility and viability, proteins concentrations and superoxide dismutase enzymatic activity in seminal plasma). In contrast, only the storage time affected the fertilising capacity and catalase enzymatic activity in seminal plasma. The resulting analysis can conclude that the antioxidant presence improves the viability of cold stored milt, especially the transport conditions and the antioxidants allow the fecundity despite motility decrease.

O armazenamento a frio de leite implica potenciais alterações em sua qualidade, pois gera como processo principal radicais livres que provocam danos aos lipídios da membrana dos espermatozoides, com as consequentes alterações na motilidade e na capacidade de fertilização. Para diminuir os danos causados pelos radicais livres, as células têm defesas antioxidantes (proteínas, enzimas e substâncias de baixo peso molecular). O presente estudo avaliou o efeito do tempo de armazenamento e diferentes antioxidantes preparados em diluentes espermáticos no armazenamento de viabilidade de O. mykiss milt a 4°C. A ANOVA de duas vias denotou que o armazenamento no tempo e a influência antioxidante têm efeitos significativos separados ou combinados nos parâmetros de viabilidade (motilidade espermática, viabilidade espermática, concentrações de proteínas e atividade enzimática da superóxido dismutase no plasma seminal), enquanto apenas o tempo de armazenamento afetou a capacidade de fertilização e atividade enzimática da catalase no plasma seminal. A análise resultante pode concluir que a presença de antioxidante melhora a viabilidade do leite frio, especialmente as condições de transporte, e os antioxidantes permitem a fecundidade apesar da diminuição da motilidade.

Use of antioxidants and time of cold storage: effects over viability parameters and enzymatic levels in semen of rainbow trout (Oncorhynchus mykiss, Walbaum, 1792)

Abstract The cold storage of milt implies potentials alterations in its quality because the storage generates as main process, free radicals that produce spermatozoa membrane lipids damage with the consequent motility and fertilising capacity disruptions. To decrease the damage generated by free radicals the cells have antioxidant defences (proteins, enzymes, and low molecular weight substances). The objective of the present study evaluated the time storage effect and different antioxidants prepared in spermatic diluents on sperm viability of O. mykiss milt stored at 4°C. The two-way ANOVA denoted that the time storage and antioxidant influence have significant effects separated or combined on viability parameters (sperm motility and viability, proteins concentrations and superoxide dismutase enzymatic activity in seminal plasma). In contrast, only the storage time affected the fertilising capacity and catalase enzymatic activity in seminal plasma. The resulting analysis can conclude that the antioxidant presence improves the viability of cold stored milt, especially the transport conditions and the antioxidants allow the fecundity despite motility decrease.

Resumo O armazenamento a frio de leite implica potenciais alterações em sua qualidade, pois gera como processo principal radicais livres que provocam danos aos lipídios da membrana dos espermatozoides, com as consequentes alterações na motilidade e na capacidade de fertilização. Para diminuir os danos causados pelos radicais livres, as células têm defesas antioxidantes (proteínas, enzimas e substâncias de baixo peso molecular). O presente estudo avaliou o efeito do tempo de armazenamento e diferentes antioxidantes preparados em diluentes espermáticos no armazenamento de viabilidade de O. mykiss milt a 4°C. A ANOVA de duas vias denotou que o armazenamento no tempo e a influência antioxidante têm efeitos significativos separados ou combinados nos parâmetros de viabilidade (motilidade espermática, viabilidade espermática, concentrações de proteínas e atividade enzimática da superóxido dismutase no plasma seminal), enquanto apenas o tempo de armazenamento afetou a capacidade de fertilização e atividade enzimática da catalase no plasma seminal. A análise resultante pode concluir que a presença de antioxidante melhora a viabilidade do leite frio, especialmente as condições de transporte, e os antioxidantes permitem a fecundidade apesar da diminuição da motilidade.

Use of antioxidants and time of cold storage: effects over viability parameters and enzymatic levels in semen of rainbow trout (Oncorhynchus mykiss, Walbaum, 1792) / Uso de antioxidantes e tempo de armazenamento a frio: efeitos sobre parâmetros de viabilidade e níveis enzimáticos no sêmen da truta arco-íris (Oncorhynchus mykiss, Walbaum, 1792)

Abstract The cold storage of milt implies potentials alterations in its quality because the storage generates as main process, free radicals that produce spermatozoa membrane lipids damage with the consequent motility and fertilising capacity disruptions. To decrease the damage generated by free radicals the cells have antioxidant defences (proteins, enzymes, and low molecular weight substances). The objective of the present study evaluated the time storage effect and different antioxidants prepared in spermatic diluents on sperm viability of O. mykiss milt stored at 4°C. The two-way ANOVA denoted that the time storage and antioxidant influence have significant effects separated or combined on viability parameters (sperm motility and viability, proteins concentrations and superoxide dismutase enzymatic activity in seminal plasma). In contrast, only the storage time affected the fertilising capacity and catalase enzymatic activity in seminal plasma. The resulting analysis can conclude that the antioxidant presence improves the viability of cold stored milt, especially the transport conditions and the antioxidants allow the fecundity despite motility decrease.

Resumo O armazenamento a frio de leite implica potenciais alterações em sua qualidade, pois gera como processo principal radicais livres que provocam danos aos lipídios da membrana dos espermatozoides, com as consequentes alterações na motilidade e na capacidade de fertilização. Para diminuir os danos causados pelos radicais livres, as células têm defesas antioxidantes (proteínas, enzimas e substâncias de baixo peso molecular). O presente estudo avaliou o efeito do tempo de armazenamento e diferentes antioxidantes preparados em diluentes espermáticos no armazenamento de viabilidade de O. mykiss milt a 4°C. A ANOVA de duas vias denotou que o armazenamento no tempo e a influência antioxidante têm efeitos significativos separados ou combinados nos parâmetros de viabilidade (motilidade espermática, viabilidade espermática, concentrações de proteínas e atividade enzimática da superóxido dismutase no plasma seminal), enquanto apenas o tempo de armazenamento afetou a capacidade de fertilização e atividade enzimática da catalase no plasma seminal. A análise resultante pode concluir que a presença de antioxidante melhora a viabilidade do leite frio, especialmente as condições de transporte, e os antioxidantes permitem a fecundidade apesar da diminuição da motilidade.

Use of antioxidants and time of cold storage: effects over viability parameters and enzymatic levels in semen of rainbow trout (Oncorhynchus mykiss, Walbaum, 1792) / Uso de antioxidantes e tempo de armazenamento a frio: efeitos sobre parâmetros de viabilidade e níveis enzimáticos no sêmen da truta arco-íris (Oncorhynchus mykiss, Walbaum, 1792)

The cold storage of milt implies potentials alterations in its quality because the storage generates as main process, free radicals that produce spermatozoa membrane lipids damage with the consequent motility and fertilising capacity disruptions. To decrease the damage generated by free radicals the cells have antioxidant defences (proteins, enzymes, and low molecular weight substances). The objective of the present study evaluated the time storage effect and different antioxidants prepared in spermatic diluents on sperm viability of O. mykiss milt stored at 4°C. The two-way ANOVA denoted that the time storage and antioxidant influence have significant effects separated or combined on viability parameters (sperm motility and viability, proteins concentrations and superoxide dismutase enzymatic activity in seminal plasma). In contrast, only the storage time affected the fertilising capacity and catalase enzymatic activity in seminal plasma. The resulting analysis can conclude that the antioxidant presence improves the viability of cold stored milt, especially the transport conditions and the antioxidants allow the fecundity despite motility decrease.(AU)

O armazenamento a frio de leite implica potenciais alterações em sua qualidade, pois gera como processo principal radicais livres que provocam danos aos lipídios da membrana dos espermatozoides, com as consequentes alterações na motilidade e na capacidade de fertilização. Para diminuir os danos causados pelos radicais livres, as células têm defesas antioxidantes (proteínas, enzimas e substâncias de baixo peso molecular). O presente estudo avaliou o efeito do tempo de armazenamento e diferentes antioxidantes preparados em diluentes espermáticos no armazenamento de viabilidade de O. mykiss milt a 4°C. A ANOVA de duas vias denotou que o armazenamento no tempo e a influência antioxidante têm efeitos significativos separados ou combinados nos parâmetros de viabilidade (motilidade espermática, viabilidade espermática, concentrações de proteínas e atividade enzimática da superóxido dismutase no plasma seminal), enquanto apenas o tempo de armazenamento afetou a capacidade de fertilização e atividade enzimática da catalase no plasma seminal. A análise resultante pode concluir que a presença de antioxidante melhora a viabilidade do leite frio, especialmente as condições de transporte, e os antioxidantes permitem a fecundidade apesar da diminuição da motilidade.(AU)

Avaliação da viabilidade de microrganismos probióticos incorporados em ração de truta-arco-íris (Oncorhynchus mykiss) / [Evaluation of the viability of probiotic microorganisms impregnated into rainbow trout (Oncorhynchus mykiss) ration]

A produção aquícola mundial tem demandado estudos que buscam soluções para os problemas produtivos e sanitários apresentados na piscicultura. Nesse contexto, o uso de produtos probióticos demonstra ser uma abordagem promissora. Dessa forma, o presente trabalho teve como objetivo avaliar a viabilidade de um pool de cepas de Lactobacillus incorporados à ração de truta-arco-íris. Para tanto, as respectivas cepas foram previamente cultivadas em caldo MRS e submetidas à criocentrifugação. As células obtidas foram ressuspensas em soro fisiológico acrescentado de 2% de óleo de soja, sendo posteriormente incorporadas à ração por meio de misturador circular. Essa ração foi devidamente armazenada sob refrigeração a 4°C, por 120 dias, sendo retiradas aleatoriamente três amostras, a cada 15 dias, para avaliação da viabilidade das bactérias, por meio da contagem em placas. Os resultados demonstraram que houve uma redução não significativa (P>0,05) na população de células viáveis, correspondente a 2%, após 30 dias de armazenamento. Verificou-se também, após esse período, uma população aproximada equivalente a 3,00 x 108 UFC/g. Dessa forma, demonstrou-se a possibilidade de desenvolvimento de formulações probióticas por meio da incorporação de cepas específicas em rações de trutas, o que poderá contribuir para o desenvolvimento de tecnologias alternativas para produção de peixes.(AU)

Among the exotic species of fish produced in Brazil, the rainbow trout (Oncorhynchus mykiss) has been highlighted during the past few years. The expansion of this sector has been intensifying the need for further studies in order to decrease production and health problems presented in aquaculture, as well as to develop alternative technics to controversial antimicrobial treatments. In this context, the use of probiotics has been shown to be a promising approach to the improvement in trout husbandry. Thus, the present study aimed to contribute to the development of an alternative technology in the rainbow trout husbandry by evaluating the effect of probiotic preparations on the performance of the animals subjected to conventional husbandry conditions or chronic stress. Therefore, in this paper we report the results regarding the evaluation of the viability of a pool of 4 Lactobacillus probiotic strains incorporated into rainbow trout ration using soybean oil as vehicle. The results have demonstrated a high efficacy of cell incorporation into the ration with high viability rate after storage for 120 days at 4°C.(AU)

Assessment and incidence of fish associated bacterial pathogens at hatcheries of Azad Kashmir, Pakistan / Avaliação e incidência de patógenos bacterianos associados a peixes em incubadoras da Caxemira de Azad, Paquistão

Fish is the most indispensable source of proteins for individuals and have high nutritional value. On the other hand, the fish culturing raised issues of fish health due to close contact between the aquatic environment and the fish pathogens. So, the aim of the current study was to identify the bacterial pathogens and screen the injured Rainbow trout rearing in different trout hatcheries run under fisheries department of the government of Azad Jammu and Kashmir, Pakistan. Seven bacterial pathogens such as Shigella flexneri, Enterobacter amnigenus, Salmonella Typhimurium, Serratia odorifera, Pseudomonas aeruginosa, Streptococcus pyogenes, and Bacillus cereus were isolated and identified. Results revealed that the injury of fish specimens was due to overcrowding. Instead of rainbow coloration, specimens have darker black in color. The water of ponds was not clean and clear and such conditions was because of the greater quantity of feed thrown in the water. It was concluded that poor hygienic water condition and overloading allowed the opportunistic bacterial contaminations to succeed which cause a serious threat to hatcheries.(AU)

O peixe é a fonte mais indispensável de proteínas para os indivíduos e tem alto valor nutricional. Por outro lado, a cultura dos peixes levantou questões sobre a saúde dos peixes devido ao próximo contato entre o ambiente aquático e os agentes patogênicos desses peixes. Assim, o objetivo do presente estudo foi identificar os patógenos bacterianos e rastrear a criação da truta arco-íris que apresentou lesões em diferentes incubadoras de trutas, com supervisão do departamento de pesca do governo de Azad Jammu e Caxemira, Paquistão. Sete patógenos bacterianos foram isolados e identificados, tais como: Shigella flexneri, Enterobacter amnigenus, Salmonella typhimurium, Serratia odorifera, Pseudomonas aeruginosa, Streptococcus pyogenes e Bacillus cereus. Os resultados revelaram que a lesão de espécimes de peixes foi devido à superlotação. Em vez da coloração do arco-íris, os espécimes tiveram uma coloração preta mais escura. A água das lagoas não era limpa e nem clara, e tais condições ocorreram devido a maior quantidade de alimento lançada na água. Concluiu-se que a precária condição higiênica da água e também a sobrecarga permitiram que as contaminações bacterianas oportunistas fossem bem-sucedidas, causando séria ameaça às incubadoras.(AU)

Assessment and incidence of fish associated bacterial pathogens at hatcheries of Azad Kashmir, Pakistan

Abstract Fish is the most indispensable source of proteins for individuals and have high nutritional value. On the other hand, the fish culturing raised issues of fish health due to close contact between the aquatic environment and the fish pathogens. So, the aim of the current study was to identify the bacterial pathogens and screen the injured Rainbow trout rearing in different trout hatcheries run under fisheries department of the government of Azad Jammu and Kashmir, Pakistan. Seven bacterial pathogens such as Shigella flexneri, Enterobacter amnigenus, Salmonella Typhimurium, Serratia odorifera, Pseudomonas aeruginosa, Streptococcus pyogenes, and Bacillus cereus were isolated and identified. Results revealed that the injury of fish specimens was due to overcrowding. Instead of rainbow coloration, specimens have darker black in color. The water of ponds was not clean and clear and such conditions was because of the greater quantity of feed thrown in the water. It was concluded that poor hygienic water condition and overloading allowed the opportunistic bacterial contaminations to succeed which cause a serious threat to hatcheries.

Resumo O peixe é a fonte mais indispensável de proteínas para os indivíduos e tem alto valor nutricional. Por outro lado, a cultura dos peixes levantou questões sobre a saúde dos peixes devido ao próximo contato entre o ambiente aquático e os agentes patogênicos desses peixes. Assim, o objetivo do presente estudo foi identificar os patógenos bacterianos e rastrear a criação da truta arco-íris que apresentou lesões em diferentes incubadoras de trutas, com supervisão do departamento de pesca do governo de Azad Jammu e Caxemira, Paquistão. Sete patógenos bacterianos foram isolados e identificados, tais como: Shigella flexneri, Enterobacter amnigenus, Salmonella typhimurium, Serratia odorifera, Pseudomonas aeruginosa, Streptococcus pyogenes e Bacillus cereus. Os resultados revelaram que a lesão de espécimes de peixes foi devido à superlotação. Em vez da coloração do arco-íris, os espécimes tiveram uma coloração preta mais escura. A água das lagoas não era limpa e nem clara, e tais condições ocorreram devido a maior quantidade de alimento lançada na água. Concluiu-se que a precária condição higiênica da água e também a sobrecarga permitiram que as contaminações bacterianas oportunistas fossem bem-sucedidas, causando séria ameaça às incubadoras.

Assessment and incidence of fish associated bacterial pathogens at hatcheries of Azad Kashmir, Pakistan

Abstract Fish is the most indispensable source of proteins for individuals and have high nutritional value. On the other hand, the fish culturing raised issues of fish health due to close contact between the aquatic environment and the fish pathogens. So, the aim of the current study was to identify the bacterial pathogens and screen the injured Rainbow trout rearing in different trout hatcheries run under fisheries department of the government of Azad Jammu and Kashmir, Pakistan. Seven bacterial pathogens such as Shigella flexneri, Enterobacter amnigenus, Salmonella Typhimurium, Serratia odorifera, Pseudomonas aeruginosa, Streptococcus pyogenes, and Bacillus cereus were isolated and identified. Results revealed that the injury of fish specimens was due to overcrowding. Instead of rainbow coloration, specimens have darker black in color. The water of ponds was not clean and clear and such conditions was because of the greater quantity of feed thrown in the water. It was concluded that poor hygienic water condition and overloading allowed the opportunistic bacterial contaminations to succeed which cause a serious threat to hatcheries.

Resumo O peixe é a fonte mais indispensável de proteínas para os indivíduos e tem alto valor nutricional. Por outro lado, a cultura dos peixes levantou questões sobre a saúde dos peixes devido ao próximo contato entre o ambiente aquático e os agentes patogênicos desses peixes. Assim, o objetivo do presente estudo foi identificar os patógenos bacterianos e rastrear a criação da truta arco-íris que apresentou lesões em diferentes incubadoras de trutas, com supervisão do departamento de pesca do governo de Azad Jammu e Caxemira, Paquistão. Sete patógenos bacterianos foram isolados e identificados, tais como: Shigella flexneri, Enterobacter amnigenus, Salmonella typhimurium, Serratia odorifera, Pseudomonas aeruginosa, Streptococcus pyogenes e Bacillus cereus. Os resultados revelaram que a lesão de espécimes de peixes foi devido à superlotação. Em vez da coloração do arco-íris, os espécimes tiveram uma coloração preta mais escura. A água das lagoas não era limpa e nem clara, e tais condições ocorreram devido a maior quantidade de alimento lançada na água. Concluiu-se que a precária condição higiênica da água e também a sobrecarga permitiram que as contaminações bacterianas oportunistas fossem bem-sucedidas, causando séria ameaça às incubadoras.

Expressão da enzima indoleamina-2, 3-dioxigenase em truta arco-íris (Oncorhynchus mykiss) / Expression of the enzyme indoleamine-2, 3-dioxygenase in Rainbow Trout (Oncorhynchus mykiss

A indoleamina 2,3-dioxigenase (IDO) é uma enzima que cataboliza o aminoácido triptofano, levando à inibição da proliferação de linfócitos T, seja pela exaustão desse aminoácido no ambiente, ou pela indução via catabólitos induzindo-os a apoptose. Em mamíferos, esta enzima atua em diversas condições do organismo como a gestação, infecções, inflamações crônicas, transplantes e tumores, atuando na regulação imunológica. Estudos recentes identificaram a presença de moléculas homólogas a IDO em espécies filogeneticamente inferiores, cuja função parece estar restrita ao metabolismo do triptofano como fonte de energia. Este estudo teve por objetivo averiguar a expressão da IDO em células sanguíneas e órgãos hematopoiéticos de truta arco-íris pela imuno-histoquímica, buscando evidências de que a mesma poderia, nesta espécie, estar relacionada ao sistema imune. A expressão de IDO foi observada nos órgãos hematopoiéticos estudados incluindo o rim cefálico que apresentou marcação em células interrenais e leucócitos; baço, na qual a marcação restringiu à alguns leucócitos; no fígado a marcação ficou limitada à apenas algumas células dentro dos vasos sanguíneos e nas extensões sanguíneas pode-se visualizar a marcação de alguns leucócitos como os monócitos, linfócitos e neutrófilos. A predominância da marcação da IDO nesses tecidos pode constituir uma evidência de que a IDO identificada na O. mykiss esteja relacionada ao sistema imunológico nessa espécie.(AU)

Indoleamine 2,3-dioxygenase (IDO) is an enzyme that catabolizes the amino acid tryptophan, leading to inhibition of T lymphocyte proliferation, whether by depletion of this amino acid in the environment, or by induction via the catabolites inducing apoptosis. In mammals, this enzyme acts on various conditions of the body such as pregnancy, infections, chronic inflammation, transplantation and tumors, acting in immune regulation. Recent studies have identified the presence of homologous molecules IDO lower phylogenetically related species, whose function appears to be confined to the tryptophan metabolism as an energy source. This study aimed to investigate the expression of IDO in blood cells and hematopoietic organs of rainbow trout by immunohistochemistry, seeking evidence that it could, this species is related to the immune system. The expression of IDO was observed in hematopoietic organs studied including head kidney that show labeling in interrenal cells and leukocytes; spleen, in which the marking restricted to a few leukocytes in the liver;, labeling was restricted to only certain cells within the blood vessels and the blood extensions can view the marking of some leukocytes including monocytes, lymphocytes and neutrophils. The predominance of IDO marking these tissues may constitute evidence that IDO identified in O. mykiss is related to the immune system in this species.(AU)

Detection of Virus Level in Tissues of Rainbow Trout, Oncoryhinchus mykiss in Clinical Stage of Viral Hemorrhagic Septicemia

In order to detecting VHS virus titer in various tissues in clinical stage of VHS disease, rainbow trout,Oncorhynchus mykiss, were exposed to virus by bath. The experiments were carried out with 140 fish obtained fromrainbow trout farm. The fish were divided into two equal groups in 120 Liter tanks containing 70 fish. Group one wasconsidered as control and group two infected by bath challenge with 103 TCID50 ml-1 of a VHS virus strain serologicallysimilar to reference strain F1 with high pathogenicity in rainbow trout. At days 12, 13 and 14 post infection the organsincluding kidney, spleen, heart, skin, liver, pyloric caeca and brain were sampled from dead fish with appropriate clinicalsigns of VHS separately. Each sample was placed in vials adding 1 ml transport medium to assess virus titer in varioustissues. Results of the study, showed that significant difference between virus loads in various organs (p≤ 0.05). Thehighest virus titer belongs to the heart while it is in minimum amount in the skin. According to the virus quantity theexperimental tissues can be divided in three categories, respectively. Heart and kidney performed the highest amount ofvirus quantities while liver, gill, pyloric caeca and skin showed the lowest with brain and spleen lying in between. Theseresults point out that the significant levels of VHS virus found in rainbow trout tissues are relevant for the biosecurity inVHS-free areas mainly when fish are displayed and retained as whole fish.

Detection of Virus Level in Tissues of Rainbow Trout, Oncoryhinchus mykiss in Clinical Stage of Viral Hemorrhagic Septicemia

In order to detecting VHS virus titer in various tissues in clinical stage of VHS disease, rainbow trout,Oncorhynchus mykiss, were exposed to virus by bath. The experiments were carried out with 140 fish obtained fromrainbow trout farm. The fish were divided into two equal groups in 120 Liter tanks containing 70 fish. Group one wasconsidered as control and group two infected by bath challenge with 103 TCID50 ml-1 of a VHS virus strain serologicallysimilar to reference strain F1 with high pathogenicity in rainbow trout. At days 12, 13 and 14 post infection the organsincluding kidney, spleen, heart, skin, liver, pyloric caeca and brain were sampled from dead fish with appropriate clinicalsigns of VHS separately. Each sample was placed in vials adding 1 ml transport medium to assess virus titer in varioustissues. Results of the study, showed that significant difference between virus loads in various organs (p≤ 0.05). Thehighest virus titer belongs to the heart while it is in minimum amount in the skin. According to the virus quantity theexperimental tissues can be divided in three categories, respectively. Heart and kidney performed the highest amount ofvirus quantities while liver, gill, pyloric caeca and skin showed the lowest with brain and spleen lying in between. Theseresults point out that the significant levels of VHS virus found in rainbow trout tissues are relevant for the biosecurity inVHS-free areas mainly when fish are displayed and retained as whole fish.(AU)

Influence of dietary vegetable crops on rainbow trout (Oncorhynchus mykiss) immune system and growth performance

Background: Carotenoids such as ß-carotene, α-carotene, lycopene, lutein and ß-cryptoxanthin are a family of pigmented compounds which are synthesized by many vegetable crops and microorganisms but not animals. In human and murine models, carotenoids are shown to mediate their effects via different mechanisms such as gap junction communication, cell growth regulation, modulating gene expression and immune response. In some fish species, the immunomodulating action of synthetic carotenoids has been the subject of some research. How ever, studies on the effects of carotenoids from natural sources on fish growth performance and immune parameters are lacking. In the current study, a preliminary study with 60 days feeding was conducted to study the influence of different natural sources of carotenoids from some vegetable crops on growth and some immune indices in rainbow trout (Oncorhynchus mykiss). Materials, Methods & Results: Purified isonitrigenous (crude protein: 40.16%) and isocaloric (3660 kcal kg-1) diet with 4.5 g of powdered crops namely tomato (Solanum lycopersicum) and sweet pepper (Capsicum annuum) per kg feed or control diet without any treatment was prepared. Rainbow trout weighing 150 ± 9 g were distributed equally into 2 groups with 33 fish in each group. Each group contained 11 fish in triplicate reared in individual ponds. In treatment group, fish were fed diet containing 4.5 g of powdered crops for 60 days while in control group, basal diet without any treatments was fed. At the end of the feeding trial, 4 fish per tank were sampled to analyze the growth parameters. Seven fish were also bled from the caudal vein to collect serum sample for immune parameters. During this study no mortality of fish was observed in different groups. Results of this study showed that condition factor and feed intake were similar among the groups while specific growth rate and weight gain showed a significant increase in treatment group compared to control group. Immunological parameters namely peroxidase content, antibacterial activity, α1-antiprotease, total antiprotease activities and total protein did not vary among the groups, even though slight decrease in serum peroxidase content was shown in treatment group. On the other hand, serum lysozyme activity of fish fed treatment diet was significantly higher than control group. Discussion: Enhanced growth performance in the current study might be attributed to some intermediary metabolism which could enhance nutrient utilization and may ultimately result in improved fi sh growth. Lysozyme is secreted by leukocytes and is a marker of leukocyte activity, increasing concomitantly with phagocytic activity. Administration of natural carotenoids in fish diet exerts a stabilizing or protective effect against oxidative damage, and enhances the proliferation of these cells, which could result in increased serum lysozyme level. Feeding natural carotenoids might act as a direct scavenger of reactive oxygen species and decrease the body's need for certain antioxidant enzymes. Therefore, slight decrease in serum peroxidase content can be attributed to this point. In conclusion, this study showed that rainbow trout appear to benefit from inclusion of crops in diet in terms of improved growth performance and immune system.

Sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis of rainbow trout (Oncorhynchus mykiss) seminal plasma proteins and their correlation with semen characteristics

Background: Fish seminal plasma is a complex mixture made of different components. In few studies on some fish species such as rainbow trout, Nile tilapia and jundiá fish (Rhamdia quelen) characterization of seminal plasma proteins were shown. Meanwhile there is little information regarding the correlation between specific seminal proteins and semen characteristics in rainbow trout. The objective of the present study was to evaluate the seminal plasma protein profiles and their relation with some semen characteristics in rainbow trout. Materials, Methods & Results: Nine mature male rainbow trout with total weight 2300 ± 200 g were used. A total of nine male fish were anaesthetized by clove oil bath (50 µl L-¹) and semen was collected by abdominal massage. Semen variables (spermatocrit, concentration, duration of activity, percent of motility, total protein) were recorded. Seminal plasma was also separated by centrifugation and subjected to SDS-PAGE analysis. Gel images were analysed to determine molecular weight and relative protein content (pixel density) using the Total Lab TL120 computer program. Spermatocrit (%), sperm concentration (cell mL-¹), duration of sperm activity (sec), percentage of sperm motility and total protein (mg dL-¹) were 22.67, 12.35 × 109, 36.56, 89.33 and 81.49 respectively. Nine protein bands were identified on the 15% gel ranging from 11.74 to 68.12 kDa which seven were present in all samples. Band 1 (68.12 kDa), 2 (60.20 kDa) and 3 (54.19 kDa) were prominent (56.92% of the bands) in semen samples. Sperm concentration was negatively correlated with band 1 (68.12 kDa), 2 (60.20 kDa), 7 (32.72 k Da) and 8 (20.96). Percent of sperm motility showed positive correlation with band 3 (54.19 kDa) and 9 (11.74). Negative correlation was also revealed between spermatocrit and band 7 (32.72 k Da). Discussion: In the present study, spermatocrit (%) and duration of sperm activity (sec) were 22.67 and 36.56. In our study values for sperm concentration (cell mL-¹) and percentage of spem motility were 12.35 × 109 and 89.33 while in previously study these values were 7.89 × 109 and 88.5. Nine bands with molecular weights ranging from 11.74 to 68.12 kDa were detected in this study. The proteins with molecular weight higher than 54 kDa were prominent (56.92% of the bands). In the current study protein bands 3 (54.19 kDa) and 9 (11.74 kDa) were positively correlated with percent of sperm motility. It can be concluded that protein band 3 (54.19) and 9 (11.74) may modulate sperm function by providing energy and protection for spermatozoa as a complementary substance. Also According to our results, protein bands 1 (68.12), 2 (60.20), 7 (32.72) and 9 (11.74) negatively correlated with sperm concentration. It seems that these protein fractions could relate to other parameters in rainbow trout semen which are detrimental to sperm cells. On the other hand, all protein bands showed no correlation with other spermatological parameters such as total protein and duration of sperm activity. In conclusion, the present study shows that there is a correlation between some of the seminal plasma protein fraction and semen characteristics.

Effects of water temperature on the susceptibility of rainbow trout to Streptococcus agalactiae

Background: The outbreak of diseases is a limiting factor in fish culture. Among different bacterial agents, Streptococcus agalactiae is a major problem, causing heavy loss in cultured and wild fish species from fresh and marine water. Outbreaks with considerable mortalities in different fish species have been associated with multiple environmental factors, including warm water temperatures, increased ammonia levels and low dissolved oxygen levels. The effects of various water quality factors on streptococcal infections have been previously shown. To date, there is no available data on the effects of water temperature on the infection of rainbow trout with S. agalactiae. Therefore, present study evaluated the effect of two water temperatures (12 and 18ºC) on clinical signs, relative percent survival (RPS), cumulative mortality and LD50 in rainbow trout against S. agalactiae. Materials, Methods & Results: Three hundred and sixty rainbow trout (56 ± 4.1 g) were acclimatized for 2 weeks and fed the commercial fish diet at 2% body weight twice daily. The experiment was conducted in two different water temperatures (12 ± 1ºC and 18 ± 1ºC). In each temperature, fish were injected with 0.2 mL of five different concentrations (108, 107, 106, 105 and 104 CFU mL-¹) of S. agalactiae (RTCC2051). In control group, the same amount of physiological saline was injected instead of the bacterial suspension. Mortality rates and clinical signs were recorded for 14 days. Throughout the experiment, different signs such as eye abnormalities, erratic swimming and body lesions were observed in fish which were exposed to high bacterial doses at 18ºC while fish kept at 12ºC were completely asymptomatic. No mortality was observed within 2 or 3 days in fish at 12ºC while at 18ºC, the mortality started growing rapidly even from first day of bacterial injections. Results also revealed that the trend of mortalities in 18ºC was quite different from 12ºC. The median lethal dose (LD50) on the 14th day was also calculated at 12 and 18ºC as 7.22 × 107 CFU mL-¹ and 1.711 × 107 CFU mL-¹, respectively. Discussion: In this study, the relationship between temperature and infection with Streptococcus agalactiae was pronounced. When the water temperature was 18ºC, mortality due to S. agalactiae was higher in rainbow trout than 12ºC. It was previously showed that the optimum temperature for growth provide the best performance of fish immune system. Non-specific and specific immune parameters in teleost decrease significantly when the water temperature is lower or higher than normal physiological range of the fish. According to current study, the higher mortality in fish kept at 18ºC might be affected by the reduction of rainbow trout immunogenic activity. On the other hand, the effects of water temperature on the progress of infection in fish species are also important. For example, manipulation of temperature and/or salinity can be used to reduce the growth rate of Flavobacterium psychrophilum. The change of virulent S. agalactiae related to water temperature in fish species needs more consideration. In conclusion, there was a clear relationship between temperature and mortality in rainbow trout against Streptococcus agalactiae and the total cumulative mortality at 18ºC was higher compared to 12ºC for every single concentration used.

Influence of dietary vegetable crops on rainbow trout (Oncorhynchus mykiss) immune system and growth performance / Influence of dietary vegetable crops on rainbow trout (Oncorhynchus mykiss) immune system and growth performance

Background: Carotenoids such as -carotene, -carotene, lycopene, lutein and -cryptoxanthin are a family of pigmented compounds which are synthesized by many vegetable crops and microorganisms but not animals. In human and murine models, carotenoids are shown to mediate their effects via different mechanisms such as gap junction communication, cell growth regulation, modulating gene expression and immune response. In some fish species, the immunomodulating action of synthetic carotenoids has been the subject of some research. However, studies on the effects of carotenoids from natural sources on fish growth performance and immune parameters are lacking. In the current study, a preliminary study with 60 days feeding was conducted to study the influence of different natural sources of carotenoids from some vegetable crops on growth and some immune indices in rainbow trout (Oncorhynchus mykiss). Materials, Methods & Results: Purified isonitrigenous (crude protein: 40.16%) and isocaloric (3660 kcal kg-1) diet with 4.5 g of powdered crops namely tomato (Solanum lycopersicum) and sweet pepper (Capsicum annuum) per kg feed or control diet without any treatment was prepared. Rainbow trout weighing 150 ± 9 g were distributed equally into 2 groups with 33 fish in each group. Each group contained 11 fish in triplicate reared in individual ponds. In treatment group, fish were fed diet

Background: Carotenoids such as -carotene, -carotene, lycopene, lutein and -cryptoxanthin are a family of pigmented compounds which are synthesized by many vegetable crops and microorganisms but not animals. In human and murine models, carotenoids are shown to mediate their effects via different mechanisms such as gap junction communication, cell growth regulation, modulating gene expression and immune response. In some fish species, the immunomodulating action of synthetic carotenoids has been the subject of some research. However, studies on the effects of carotenoids from natural sources on fish growth performance and immune parameters are lacking. In the current study, a preliminary study with 60 days feeding was conducted to study the influence of different natural sources of carotenoids from some vegetable crops on growth and some immune indices in rainbow trout (Oncorhynchus mykiss). Materials, Methods & Results: Purified isonitrigenous (crude protein: 40.16%) and isocaloric (3660 kcal kg-1) diet with 4.5 g of powdered crops namely tomato (Solanum lycopersicum) and sweet pepper (Capsicum annuum) per kg feed or control diet without any treatment was prepared. Rainbow trout weighing 150 ± 9 g were distributed equally into 2 groups with 33 fish in each group. Each group contained 11 fish in triplicate reared in individual ponds. In treatment group, fish were fed diet

Effects of water temperature on the susceptibility of rainbow trout to Streptococcus agalactiae / Effects of water temperature on the susceptibility of rainbow trout to Streptococcus agalactiae

Background: The outbreak of diseases is a limiting factor in fish culture. Among different bacterial agents, Streptococcus agalactiae is a major problem, causing heavy loss in cultured and wild fish species from fresh and marine water. Outbreaks with considerable mortalities in different fish species have been associated with multiple environmental factors, including warm water temperatures, increased ammonia levels and low dissolved oxygen levels. The effects of various water quality factors on streptococcal infections have been previously shown. To date, there is no available data on the effects of water temperature on the infection of rainbow trout with S. agalactiae. Therefore, present study evaluated the effect of two water temperatures (12 and 18ºC) on clinical signs, relative percent survival (RPS), cumulative mortality and LD50 in rainbow trout against S. agalactiae. Materials, Methods & Results: Three hundred and sixty rainbow trout (56 ± 4.1 g) were acclimatized for 2 weeks and fed the commercial fish diet at 2% body weight twice daily. The experiment was conducted in two different water temperatures (12 ± 1ºC and 18 ± 1ºC). In each temperature, fish were injected with 0.2 mL of five different concentrations (108, 107, 106, 105 and 104 CFU mL-1) of S. agalactiae (RTCC2051). In control group, the same amount of physiological saline was injected instead of the bacte

Background: The outbreak of diseases is a limiting factor in fish culture. Among different bacterial agents, Streptococcus agalactiae is a major problem, causing heavy loss in cultured and wild fish species from fresh and marine water. Outbreaks with considerable mortalities in different fish species have been associated with multiple environmental factors, including warm water temperatures, increased ammonia levels and low dissolved oxygen levels. The effects of various water quality factors on streptococcal infections have been previously shown. To date, there is no available data on the effects of water temperature on the infection of rainbow trout with S. agalactiae. Therefore, present study evaluated the effect of two water temperatures (12 and 18ºC) on clinical signs, relative percent survival (RPS), cumulative mortality and LD50 in rainbow trout against S. agalactiae. Materials, Methods & Results: Three hundred and sixty rainbow trout (56 ± 4.1 g) were acclimatized for 2 weeks and fed the commercial fish diet at 2% body weight twice daily. The experiment was conducted in two different water temperatures (12 ± 1ºC and 18 ± 1ºC). In each temperature, fish were injected with 0.2 mL of five different concentrations (108, 107, 106, 105 and 104 CFU mL-1) of S. agalactiae (RTCC2051). In control group, the same amount of physiological saline was injected instead of the bacte

Sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis of rainbow trout (Oncorhynchus mykiss) seminal plasma proteins and their correlation with semen characteristics / Sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis of rainbow trout (Oncorhynchus mykiss) seminal plasma proteins and their correlation with semen characteristics

Background: Fish seminal plasma is a complex mixture made of different components. In few studies on some fish species such as rainbow trout, Nile tilapia and jundiá fish (Rhamdia quelen) characterization of seminal plasma proteins were shown. Meanwhile there is little information regarding the correlation between specific seminal proteins and semen characteristics in rainbow trout. The objective of the present study was to evaluate the seminal plasma protein profiles and their relation with some semen characteristics in rainbow trout. Materials, Methods & Results: Nine mature male rainbow trout with total weight 2300 ± 200 g were used. A total of nine male fish were anaesthetized by clove oil bath (50 µl L-1) and semen was collected by abdominal massage. Semen variables (spermatocrit, concentration, duration of activity, percent of motility, total protein) were recorded. Seminal plasma was also separated by centrifugation and subjected to SDS-PAGE analysis. Gel images were analysed to determine molecular weight and relative protein content (pixel density) using the Total Lab TL120 computer program. Spermatocrit (%), sperm concentration (cell mL-1), duration of sperm activity (sec), percentage of sperm motility and total protein (mg dL-1) were 22.67, 12.35 × 109, 36.56, 89.33 and 81.49 respectively. Nine protein bands were identified on the 15% gel ranging from 11.74 to 68.

Background: Fish seminal plasma is a complex mixture made of different components. In few studies on some fish species such as rainbow trout, Nile tilapia and jundiá fish (Rhamdia quelen) characterization of seminal plasma proteins were shown. Meanwhile there is little information regarding the correlation between specific seminal proteins and semen characteristics in rainbow trout. The objective of the present study was to evaluate the seminal plasma protein profiles and their relation with some semen characteristics in rainbow trout. Materials, Methods & Results: Nine mature male rainbow trout with total weight 2300 ± 200 g were used. A total of nine male fish were anaesthetized by clove oil bath (50 µl L-1) and semen was collected by abdominal massage. Semen variables (spermatocrit, concentration, duration of activity, percent of motility, total protein) were recorded. Seminal plasma was also separated by centrifugation and subjected to SDS-PAGE analysis. Gel images were analysed to determine molecular weight and relative protein content (pixel density) using the Total Lab TL120 computer program. Spermatocrit (%), sperm concentration (cell mL-1), duration of sperm activity (sec), percentage of sperm motility and total protein (mg dL-1) were 22.67, 12.35 × 109, 36.56, 89.33 and 81.49 respectively. Nine protein bands were identified on the 15% gel ranging from 11.74 to 68.

Effects of dietary propolis and vitamin E on growth performance and antioxidant status in blood of juvenile Rainbow trout, Oncorhynchus mykiss (Teleostei: Salmoniformes) under different flow rates

The present study investigated the effects of propolis and vitamin E supplementation in diets of juvenil rainbow trout subjected to two different flow rates with or without flow stress (0.9 and 2.1 l/min, respectively) on final weigth (FW), condition factor (CF), feed conservation ratio (FCR), protein efficiency ratio (PER) and vitamin A, C and E concentrations and malondialdehyde (MDA) levels in serum as well as plasma superoxide dismutase (SOD) activity. The experimental groups were as follows: group C was fed a basal diet, group P10 was fed a basal diet supplemented with 10 g propolis/kg, group P30 was fed a basal diet supplemented with 30 g propolis/kg, group E60 was fed a basal diet supplemented with 60 mg vitamin E/kg. CF and PER were not different among all diets groups for both flow rate treatments (p > 0.05). The FCR improved in P10, P30 and E60 diet groups compared to C diet group at 2.1 l/min flow rate (p 0.05). The FCR of E60 and P30 were found to be better than C and P10 diet groups at 0.9 l/min flow rate (p 0.05). Vitamin E and propolis supplementations did not affect vitamin A concentration of serum for either flow rate (p > 0.05). Fish fed with diet E60had higher serum vitamin E concentration than other groups (p 0.05). Serum Vitamin C concentration was only affected by the propolis supplemented diets. MDA level of E60 group was found significantly lower comperad to other groups for both flow rate (p 0.05). Plasma SOD activity significantly decreased in the E60 group compared to other groups at 2.1 l/min flow rate (p 0.05). But plasma SOD activity was not different among all diets groups at 0.9 l/min flow rate (p > 0.05).

Effects of dietary propolis and vitamin E on growth performance and antioxidant status in blood of juvenile Rainbow trout, Oncorhynchus mykiss (Teleostei: Salmoniformes) under different flow rates

The present study investigated the effects of propolis and vitamin E supplementation in diets of juvenil rainbow trout subjected to two different flow rates with or without flow stress (0.9 and 2.1 l/min, respectively) on final weigth (FW), condition factor (CF), feed conservation ratio (FCR), protein efficiency ratio (PER) and vitamin A, C and E concentrations and malondialdehyde (MDA) levels in serum as well as plasma superoxide dismutase (SOD) activity. The experimental groups were as follows: group C was fed a basal diet, group P10 was fed a basal diet supplemented with 10 g propolis/kg, group P30 was fed a basal diet supplemented with 30 g propolis/kg, group E60 was fed a basal diet supplemented with 60 mg vitamin E/kg. CF and PER were not different among all diets groups for both flow rate treatments (p > 0.05). The FCR improved in P10, P30 and E60 diet groups compared to C diet group at 2.1 l/min flow rate (p 0.05). The FCR of E60 and P30 were found to be better than C and P10 diet groups at 0.9 l/min flow rate (p 0.05). Vitamin E and propolis supplementations did not affect vitamin A concentration of serum for either flow rate (p > 0.05). Fish fed with diet E60had higher serum vitamin E concentration than other groups (p 0.05). Serum Vitamin C concentration was only affected by the propolis supplemented diets. MDA level of E60 group was found significantly lower comperad to other groups for both flow rate (p 0.05). Plasma SOD activity significantly decreased in the E60 group compared to other groups at 2.1 l/min flow rate (p 0.05). But plasma SOD activity was not different among all diets groups at 0.9 l/min flow rate (p > 0.05).

Effects of dietary propolis and vitamin E on growth performance and antioxidant status in blood of juvenile Rainbow trout, Oncorhynchus mykiss (Teleostei: Salmoniformes) under different flow rates

The present study investigated the effects of propolis and vitamin E supplementation in diets of juvenil rainbow trout subjected to two different flow rates with or without flow stress (0.9 and 2.1 l/min, respectively) on final weigth (FW), condition factor (CF), feed conservation ratio (FCR), protein efficiency ratio (PER) and vitamin A, C and E concentrations and malondialdehyde (MDA) levels in serum as well as plasma superoxide dismutase (SOD) activity. The experimental groups were as follows: group C was fed a basal diet, group P10 was fed a basal diet supplemented with 10 g propolis/kg, group P30 was fed a basal diet supplemented with 30 g propolis/kg, group E60 was fed a basal diet supplemented with 60 mg vitamin E/kg. CF and PER were not different among all diets groups for both flow rate treatments (p > 0.05). The FCR improved in P10, P30 and E60 diet groups compared to C diet group at 2.1 l/min flow rate (p 0.05). The FCR of E60 and P30 were found to be better than C and P10 diet groups at 0.9 l/min flow rate (p 0.05). Vitamin E and propolis supplementations did not affect vitamin A concentration of serum for either flow rate (p > 0.05). Fish fed with diet E60had higher serum vitamin E concentration than other groups (p 0.05). Serum Vitamin C concentration was only affected by the propolis supplemented diets. MDA level of E60 group was found significantly lower comperad to other groups for both flow rate (p 0.05). Plasma SOD activity significantly decreased in the E60 group compared to other groups at 2.1 l/min flow rate (p 0.05). But plasma SOD activity was not different among all diets groups at 0.9 l/min flow rate (p > 0.05).