Feeding habit of Brown trout (Salmo trutta fario) in upper parts of river Swat, Pakistan / Hábito de alimentação da truta marrom (Salmo trutta fario) nas partes superiores do rio Swat, Paquistão

Salmo trutta fario is the most important fish species of family Salmonidae inhibited in cool waters all over the world including the nortern parts of Pakistan. This study was aimed to find out the prey selection and feeding habits of the species. One hundred and eighty five Salmo trutta fario were captured from March 2016 to April 2017. Feeding intensity as represented by a fullness index (FI), changing with various length groups and season. Out of 185 Brown trout 24 fish stomaches were found empty. The most important and common food items of brown trout were Brachycentridae, Blepharocera, Hydropsychidae, ephemerella spp. Kruskal Wallis H-test were applied on feeding intensity groups consisting of three month group. The test statistic for K.W-H-test were (H=8.13 with df =3) had a p-value of 0.043 < (alpha=0.05 indicates favor of the alternative hypothesis of at least one difference among the feeding intensity groups. The linear relationship of N with index of relative importance and %IRI denoted by least square regression line (N = 35.2 + 22.1%IRI), shows that for 22 prey there is 1% change in IRI. The relationship between total length (mm) and fish body weight (gm) is expressed by Pearson correlation coefficient (r = 0.976), showed that total length (mm) and fish body weight (gm.) is highly correlated. Descriptive statistics are used for the stomach fullness, which shows that feeding intensity was recorded higher from March to May. A total of 2289 preys was recorded including the most common were; Trichoptera, Hydropsychidae, Brachycentridae, diptera, blepharocera, ephemerala, chironomida, honey bees, grass hopper, locust, trout egg, trochanter, plant tissue, stones were retrieved from the gut contents of brown trout. According to index of relative importance IRI% four preys represents major components of the diet. The highest IRI% was recorded in Brachycentridae (39.38%), followed by blepharocera (13.23%), [...].

Salmo trutta fario é a espécie de peixe mais importante da família dos salmonídeos, inibida em águas frias em todo o mundo, incluindo as partes do noroeste do Paquistão. Este estudo teve como objetivo conhecer a seleção de presas e os hábitos alimentares da espécie. Cento e oitenta e cinco Salmo trutta fario foram capturados de março de 2016 a abril de 2017. Intensidade de alimentação representada por um índice de plenitude (FI), mudando com vários grupos de comprimento e estação. De 185 trutas, 24 estômagos de peixes foram encontrados vazios. Os itens alimentares mais importantes e comuns da truta marrom foram brachycentridae, blepharocera, hydropsychidae, ephemerellaspp. O teste H de Kruskal Wallis foi aplicado em grupos de intensidade de alimentação consistindo de um grupo de três meses. A estatística de teste para o teste KW-H foi (H = 8,13 com df = 3) teve um valor de p de 0,043 <(alfa = 0,05 indica favor da hipótese alternativa de pelo menos uma diferença entre os grupos de intensidade de alimentação. relação de N com o índice de importância relativa e% IRI denotado pela linha de regressão do mínimo quadrado (N = 35,2 + 22,1% IRI), mostra que para 22 presas há 1% de mudança no IRI. A relação entre comprimento total (mm) e peixes o peso corporal (gm) é expresso pelo coeficiente de correlação de Pearson (r = 0,976), mostrou que o comprimento total (mm) e o peso corporal dos peixes (gm.) são altamente correlacionados. Estatísticas descritivas são usadas para a plenitude do estômago, o que mostra que a intensidade da alimentação foi registrado mais alto de março a maio. Um total de 2.289 presas foi registrado, incluindo os mais comuns foram; trichoptera, hydropsychidae, brachycentridae, diptera, blepharocera, efemérala, chironomida, abelhas, funil de grama, gafanhoto, ovo de truta, trocânter, tecido vegetal, pedras foram retiradas do intestino conteúdo de truta marrom. De acordo com o índice de importância relativa [...].

Prevalence of rhabdochoniasis in snow trout of river Swat and river Panjkora, Khyber Pakhtunkhwa province, Pakistan / Prevalência de rabdoconíase em trutas das neves do rio Swat e do rio Panjkora, província de Khyber Pakhtunkhwa, Paquistão

This research was aimed to explore the helminth parasitic diseases in Schizothorax plagiostomus (the snow trout) from river Swat and river Panjkora, Pakistan. Collection of 360 fish specimens have done from the lower, middle and upper reaches of both the rivers through gill nets, cast nets, dragon nets and hooks. All the samples were examined in the University of Malakand, Zoology Department for helminth parasites during the months from January 2015 to December 2016. Of the total examined fish samples 21.9% (n=79) were infected with Rhabdochona spp including 17.7% (n=32/180) in river Swat and 26.6% (n=47/180) in river Panjkora. Highest month-wise prevalence (p=0.09878,p0.05) prevalence (28.8%) than males (16.6%). Fishes of the lower reaches had highest (p=0.0029, P>0.05) prevalence (31.7%) followed by middle reaches (16.5%) while the lowest prevalence was observed in samples of fish collected from upper reaches (9.87%). Present study address that Rhabdochona spp in the intestine of snow trout has a long term relationship and call as a natural infection in cyprinids and zoonotic risk to human.

Esta pesquisa teve como objetivo explorar as doenças parasitárias por helmintos em Schizothorax plagiostomus (a truta das neves) do rio Swat e do rio Panjkora, Paquistão. A coleta de 360 espécimes de peixes foi feita nos trechos inferior, médio e superior de ambos os rios por meio de redes de emalhar, de lançamento, de dragão e anzóis. Todas as amostras foram examinadas na Universidade de Malakand, Departamento de Zoologia, para helmintos parasitas durante os meses de janeiro de 2015 a dezembro de 2016. Do total de amostras de peixes examinadas, 21,9% (n = 79) estavam infectados com Rhabdochona spp, incluindo 17,7% (n = 32/180) no rio Swat e 26,6% (n = 47/180) no rio Panjkora. A maior prevalência no mês (p = 0,09878, p 0,05) prevalência (28,8%) do que o masculino (16,6%). Os peixes do curso inferior tiveram maior (p = 0,0029, P> 0,05) prevalência (31,7%) seguida do curso médio (16,5%), enquanto a menor prevalência foi observada em amostras de peixes coletados do curso superior (9,87%). O presente estudo aborda que Rhabdochona spp no intestino da truta das neves tem uma relação de longo prazo e pode ser considerada uma infecção natural em ciprinídeos e risco zoonótico para humanos.

Feeding habit of Brown trout (Salmo trutta fario) in upper parts of river Swat, Pakistan / Hábito de alimentação da truta marrom (Salmo trutta fario) nas partes superiores do rio Swat, Paquistão

Salmo trutta fario is the most important fish species of family Salmonidae inhibited in cool waters all over the world including the nortern parts of Pakistan. This study was aimed to find out the prey selection and feeding habits of the species. One hundred and eighty five Salmo trutta fario were captured from March 2016 to April 2017. Feeding intensity as represented by a fullness index (FI), changing with various length groups and season. Out of 185 Brown trout 24 fish stomaches were found empty. The most important and common food items of brown trout were Brachycentridae, Blepharocera, Hydropsychidae, ephemerella spp. Kruskal Wallis H-test were applied on feeding intensity groups consisting of three month group. The test statistic for K.W-H-test were (H=8.13 with df =3) had a p-value of 0.043 < (alpha=0.05 indicates favor of the alternative hypothesis of at least one difference among the feeding intensity groups. The linear relationship of N with index of relative importance and %IRI denoted by least square regression line (N = 35.2 + 22.1%IRI), shows that for 22 prey there is 1% change in IRI. The relationship between total length (mm) and fish body weight (gm) is expressed by Pearson correlation coefficient (r = 0.976), showed that total length (mm) and fish body weight (gm.) is highly correlated. Descriptive statistics are used for the stomach fullness, which shows that feeding intensity was recorded higher from March to May. A total of 2289 preys was recorded including the most common were; Trichoptera, Hydropsychidae, Brachycentridae, diptera, blepharocera, ephemerala, chironomida, honey bees, grass hopper, locust, trout egg, trochanter, plant tissue, stones were retrieved from the gut contents of brown trout. According to index of relative importance IRI% four preys represents major components of the diet. The highest IRI% was recorded in Brachycentridae (39.38%), followed by blepharocera (13.23%), Hydropsychidae (10.76%) and ephemerella spp (8.28%). The relationship between IRI and FO is (r =0.556) is moderately correlated with coefficient of determination (r2=0.31). This study will help in the development of an artificial diet for the species for better growth performance in captivity.

Salmo trutta fario é a espécie de peixe mais importante da família dos salmonídeos, inibida em águas frias em todo o mundo, incluindo as partes do noroeste do Paquistão. Este estudo teve como objetivo conhecer a seleção de presas e os hábitos alimentares da espécie. Cento e oitenta e cinco Salmo trutta fario foram capturados de março de 2016 a abril de 2017. Intensidade de alimentação representada por um índice de plenitude (FI), mudando com vários grupos de comprimento e estação. De 185 trutas, 24 estômagos de peixes foram encontrados vazios. Os itens alimentares mais importantes e comuns da truta marrom foram brachycentridae, blepharocera, hydropsychidae, ephemerellaspp. O teste H de Kruskal Wallis foi aplicado em grupos de intensidade de alimentação consistindo de um grupo de três meses. A estatística de teste para o teste KW-H foi (H = 8,13 com df = 3) teve um valor de p de 0,043 <(alfa = 0,05 indica favor da hipótese alternativa de pelo menos uma diferença entre os grupos de intensidade de alimentação. relação de N com o índice de importância relativa e% IRI denotado pela linha de regressão do mínimo quadrado (N = 35,2 + 22,1% IRI), mostra que para 22 presas há 1% de mudança no IRI. A relação entre comprimento total (mm) e peixes o peso corporal (gm) é expresso pelo coeficiente de correlação de Pearson (r = 0,976), mostrou que o comprimento total (mm) e o peso corporal dos peixes (gm.) são altamente correlacionados. Estatísticas descritivas são usadas para a plenitude do estômago, o que mostra que a intensidade da alimentação foi registrado mais alto de março a maio. Um total de 2.289 presas foi registrado, incluindo os mais comuns foram; trichoptera, hydropsychidae, brachycentridae, diptera, blepharocera, efemérala, chironomida, abelhas, funil de grama, gafanhoto, ovo de truta, trocânter, tecido vegetal, pedras foram retiradas do intestino conteúdo de truta marrom. De acordo com o índice de importância relativa IRI%, quatro presas representam os principais componentes da dieta. O maior IRI% foi registrado em brachycentridae (39,38%), seguido por blepharocera (13,23%), hydropsychidae (10,76%) e ephemerellaspp (8,28%). A relação entre IRI e FO é (r = 0,556) está moderadamente correlacionada com o coeficiente de determinação (r2 = 0,31). Este estudo auxiliará no desenvolvimento de uma dieta artificial para a espécie para melhor desempenho de crescimento em cativeiro.

Prevalence of rhabdochoniasis in snow trout of river Swat and river Panjkora, Khyber Pakhtunkhwa province, Pakistan / Prevalência de rabdoconíase em trutas das neves do rio Swat e do rio Panjkora, província de Khyber Pakhtunkhwa, Paquistão

This research was aimed to explore the helminth parasitic diseases in Schizothorax plagiostomus (the snow trout) from river Swat and river Panjkora, Pakistan. Collection of 360 fish specimens have done from the lower, middle and upper reaches of both the rivers through gill nets, cast nets, dragon nets and hooks. All the samples were examined in the University of Malakand, Zoology Department for helminth parasites during the months from January 2015 to December 2016. Of the total examined fish samples 21.9% (n=79) were infected with Rhabdochona spp including 17.7% (n=32/180) in river Swat and 26.6% (n=47/180) in river Panjkora. Highest month-wise prevalence (p=0.09878,p<0.05) was reported in May (30%), then by February and October each (26.6%) while the lowest during August (13.3%). Highest prevalence (p=0.9723, p<0.05) was reported in summer season (26.6%), while lowest in the winter season (20%). Adults were highly infected (p=< 0.0001) in prevalence (63.7%) followed by sub-adults (13.2%) while no infection was found in juvenile specimens. Females fish samples had higher (p=0.0277, p>0.05) prevalence (28.8%) than males (16.6%). Fishes of the lower reaches had highest (p=0.0029, P>0.05) prevalence (31.7%) followed by middle reaches (16.5%) while the lowest prevalence was observed in samples of fish collected from upper reaches (9.87%). Present study address that Rhabdochona spp in the intestine of snow trout has a long term relationship and call as a natural infection in cyprinids and zoonotic risk to human.

Esta pesquisa teve como objetivo explorar as doenças parasitárias por helmintos em Schizothorax plagiostomus (a truta das neves) do rio Swat e do rio Panjkora, Paquistão. A coleta de 360 espécimes de peixes foi feita nos trechos inferior, médio e superior de ambos os rios por meio de redes de emalhar, de lançamento, de dragão e anzóis. Todas as amostras foram examinadas na Universidade de Malakand, Departamento de Zoologia, para helmintos parasitas durante os meses de janeiro de 2015 a dezembro de 2016. Do total de amostras de peixes examinadas, 21,9% (n = 79) estavam infectados com Rhabdochona spp, incluindo 17,7% (n = 32/180) no rio Swat e 26,6% (n = 47/180) no rio Panjkora. A maior prevalência no mês (p = 0,09878, p <0,05) foi relatada em maio (30%), depois em fevereiro e outubro cada (26,6%), enquanto a menor em agosto (13,3%). A maior prevalência (p = 0,9723, p <0,05) foi relatada no verão (26,6%), enquanto a menor no inverno (20%). Os adultos foram altamente infectados (p = <0,0001) na prevalência (63,7%), seguidos por subadultos (13,2%), enquanto nenhuma infecção foi encontrada em espécimes juvenis. As amostras de peixes do sexo feminino tiveram maior (p = 0,0277, p> 0,05) prevalência (28,8%) do que o masculino (16,6%). Os peixes do curso inferior tiveram maior (p = 0,0029, P> 0,05) prevalência (31,7%) seguida do curso médio (16,5%), enquanto a menor prevalência foi observada em amostras de peixes coletados do curso superior (9,87%). O presente estudo aborda que Rhabdochona spp no intestino da truta das neves tem uma relação de longo prazo e pode ser considerada uma infecção natural em ciprinídeos e risco zoonótico para humanos.

Obtención y evaluación de concentrado proteico hidrolizado de residuos animales como alternativa de alimentación en Piaractus brachypomus (Cuvier 1818) / Obtaining and evaluating hydrolyzed protein concentrate from animal waste as a feeding alternative in Piaractus brachypomus (Cuvier 1818)

RESUMEN En la industria acuícola, se vienen desarrollando acciones encaminadas a buscar fuentes proteicas alternativas palatables y de alto valor biológico para reemplazar las fuentes convencionales. Debido al potencial nutricional de los subproductos animales, se han adoptado tecnologías para su uso, como las técnicas de bioconversión por hidrólisis enzimática. En consecuencia, el objetivo de este estudio fue obtener y evaluar un concentrado de proteína hidrolizada de residuos animales (CPHRA) como alternativa en dietas para Piaractus brachypomus. Las vísceras de los subproductos avícolas se evaluaron utilizando ácido fórmico y vísceras de trucha al 20% para promover la hidrólisis enzimática a un pH más bajo (pH 3,66). El producto resultante se utilizó en la formulación de dietas para determinar coeficiente de digestibilidad aparente (CDA) de energía y nutrientes, utilizando una dieta control () y tres dietas con inclusión de 10%, 20% y 30% de CPHRA (T1, T2 y T3). Se alimentaron por triplicado ciento veinte juveniles de híbridos de cachama blanca con un peso promedio de 145 ± 3,0 g. La CPHRA presentó alto contenido proteico y se evidenciaron diferencias significativas (p < 0,05) para los CDA de materia seca, proteína bruta, grasa bruta, energía bruta y absorción de cenizas, calcio y fósforo. Los CDA de nutrientes y energía estaban por encima del 80%. En consecuencia, el concentrado de proteína hidrolizada de los desechos de aves de corral tiene un gran potencial como alternativa proteica y energética de alto valor nutricional en la alimentación de los peces.

ABSTRACT The aquaculture industry aims to find new strategies to replace fishmeal in formulated diet-sources with high attraction and palatability and high biological value to replace conventional sources. Due to the nutritional potential of animal by-products, technologies have been adopted for their use, such as bioconversion techniques by enzymatic hydrolysis. Consequently, the objective of this study was obtaining and evaluating a hydrolyzed protein concentrate of animal waste (CPHRA, by its Spanish acronym) in diets for Piaractus brachypomus. Viscera from poultry by-products was evaluated by using formic acid and a 20% trout viscera to promote the catalyst at lower pH (3,66). The resulting product was used in feed formulation to determine the Apparent Digestibility Coefficient (ADC) of energy and nutrients, using a control diet (T0) and three diets with 10%, 20%, and 30% CPHRA (T1, T2 y T3). One hundred and twenty juveniles of hybrids of cachama blanca with an average weight of 145 ± 3,0 g were fed in triplicate groups. The CPHRA presented high protein content and significant differences (p < 0,05) were evidenced for the ADCs of dry matter, crude protein, crude fat, crude energy, and ash absorption, calcium and phosphorus. The ADCs for nutrients and energy were above 80%. Accordingly, the hydrolyzed protein concentrate from poultry waste has great potential as a protein and energy alternative of high nutritional value in fish feeding.

Assessing the growth of Arctic charr (Salvelinus alpinus) (Linnaeus, 1758) in four salinities, under experimental conditions / Avaliando o crescimento do Charr Ártico (Salvelinus alpinus) (Linnaeus, 1758) em quatro salinidades, sob condições experimentais

Abstract Studies in Salvelinus alpinus, Arctic charr, indicate that it has a low capacity to hyposmorregulatory or adaption to sea in winter periods in Arctic waters. The investigation finds to determinate the rank optimum of salinity to can cultivate this species at Chile. The weight adequate was determined to join on the sea by analysis of gill Na+, K+-ATPase activity, that it was found between the ranks 80-130 g, with 14.5 U/mg. It underwent evaluation of fish growth of 72 g salinities from 0 (control), 18, 25 and 33 g/L (sea water) for 94 days. The results indicate that the largest increases were obtained in brackish water. T18 g/L and T25 g/L achieved growth of 25% and 19% on day 94 and term sampling respectively. It is important to mention that the 8% that survived in seawater introduced percentages growth 16.6% equivalent to brackish water and control. These results suggest that Salvelinus alpinus can grow in seawater, with levels of Na+, K+-ATPase similar to those submitted by Salmo salar with a weight not less than 80 g.

Resumo Estudos em Salvelinus alpinus, Charr Ártico, indicam que tem baixa capacidade de hiposmorregulação ou adaptação ao mar em períodos de inverno nas águas do Ártico. A investigação determina o melhor nível de salinidade para cultivar esta espécie no Chile. Determinou-se o peso adequado para se unir ao mar pela análise da atividade da Na +, K + -ATPase das brânquias, que foi encontrada entre as faixas de 80 a 130 g, com 14,5 U/mg. Foi avaliado o crescimento de 72 g salinidades de 0 (controle), 18, 25 e 33 g/L (água do mar) por 94 dias. Os resultados indicam que os maiores aumentos foram obtidos em água salobra. T18 g/L e T25 g/L alcançaram crescimento de 25% e 19% no dia 94 e amostragem a termo, respectivamente. É importante mencionar que os 8% que sobreviveram na água do mar apresentaram percentuais de crescimento de 16,6% equivalentes a água salobra e controle. Estes resultados sugerem que o Salvelinus alpinus pode crescer em água do mar, com níveis de Na +, K + -ATPase semelhantes aos apresentados por Salmo salar com um peso não inferior a 80 g.

First study of food webs in a large glacial river: the trophic role of invasive trout

The aim of this study was to determine the food webs structure of a large Patagonian river in two river sections (Upstream and Midstream) and to evaluate isotopic overlap between native and introduced species. We used stable isotope analyses of δ15N and δ13C and stomach content. The Upstream section had a more complex food webs structure with a greater richness of macroinvertebrates and fish species than Midstream. Upstream basal resources were dominated by filamentous algae. Lake Trout were found to have a higher trophic position than all other fish species in that area although, the most abundant fish species, were Rainbow Trout. Depending on the life stage, Rainbow Trout shifted from prey to competitor/predator. In the Midstream section, the base of the food webs was dominated by coarse particulate organic matter, and adult Rainbow Trout had the highest trophic level. Isotopic values changed among macroinvertebrates and fish for both areas. The two most abundant native and invasive species — Puyen and Rainbow Trout — showed an isotopic separation in Midstream but did not in Upstream areas. The presence of invasive fish that occupy top trophic levels can have a significant impact on native fish populations that have great ecological importance in the region.(AU)

El objetivo de este estudio fue determinar la estructura trófica de un gran río de la Patagonia en dos secciones (río arriba y medio) y evaluar la superposición isotópica entre especies nativas e introducidas. Utilizamos análisis de isótopos estables δ15N y δ13C y contenido estomacal. La sección río arriba tuvo una estructura de trama trófica más compleja, con mayor riqueza de macroinvertebrados y peces respecto de la sección media. Los recursos basales dominantes río arriba fueron las algas filamentosas. En esta área, la trucha de lago tuvo la posición trófica más alta entre los peces, aunque, las especies de peces más abundantes fueron las truchas arcoiris. Dependiendo del estadio, la trucha arcoiris cambió su rol de presa a competidor/depredador. En la sección media del río, la base de la trama trófica estuvo dominada por materia orgánica particulada gruesa y la trucha arcoíris adulta fue el depredador tope. Los valores isotópicos variaron entre zonas para invetebrados y peces. Las dos especies nativas e invasoras más abundantes, Puyen y trucha arcoiris, mostraron una separación isotópica en la sección media, pero no en secciones de río arriba. La presencia de peces invasores que ocupan una posición tope en los niveles tróficos puede tener un impacto significativo sobre las poblaciones de peces nativos de gran importancia ecológica en la región.(AU)

Effect of temperature on the expression of IFN-1 (α), STAT-1 and Mx-1 genes in Oncorhynchus mykiss (Salmoniformes: Salmonidae) exposed with the virus of the infectious pancreatic necrosis (IPNV) / Efecto de la temperatura sobre la expresión de genes IFN-1(α), STAT-1 y Mx-1 en alevines de trucha arcoíris Oncorhynchus mykiss (Salmoniformes: Salmonidae) expuestos al el virus de la necrosis pancreática infecciosa (IPNV)

The infectious pancreatic necrosis (IPNV) is the causative agent of an acute illness well characterized in salmonids worldwide. Clinical signs and mortality rates are dependent on several factors such as the viral dose, the age of the fish, the water temperature, among others. An experimental study was conducted to measure the effect of temperature on the gene expression profile of IFN-1(α), STAT-1 and Mx-1 in rainbow trout fry, exposed to IPNV. Fry (n=198) were exposed at 8, 12 and 16°C, and samples were taken for 21 days to determine the virus titer and gene expression. In the first 11 days the greatest viral titer was recorded at 8°C compared with the values obtained at 12 and 16°C. At 8°C, there was a significant increase on day 4 of mRNA Mx-1 (t-test, p<0.05), time in which the viral titer began to decrease. Furthermore, as the viral titer increased, STAT-1 and Mx-1 (r=0.91) and (r=0.96) increased, respectively. The animals were able to recover from day 4 from some of the symptoms of IPN. Clinical disease was developed only in fish exposed to 12°C and all died between days 6 and 14, despite the highly significant increase shown in the average expression level of Mx-1, compared with the values recorded at 8°C and 16°C (Tukey, p<0.0001). Additionally, the expression profiles of IFN-1(α) and STAT-1 decreased completely (~0.016) and (~0.020 times) on day 7. The highest expression level of IFN-1(α), occurred at 16°C (Tukey, p<0.0005). Fry exposed at 16°C were normal during the experiment. IFN-1(α) possibly generated a protector effect from day 2 when they showed a significant expression increase compared with the results at 8°C and 12°C (t-student, p<0.0001); however, STAT-1 was not significantly affected by temperature, although the highest average expression value was recorded at 16°C. Our research supports the expression of relevant anti-viral response genes as IFN-1(α), STAT-1 and Mx-1 are physiologically modulated by the water temperature, directly influencing the development of the IPN disease in rainbow trout.

El virus de la necrosis pancreática infecciosa (IPNV) es el agente etiológico de una enfermedad aguda bien caracterizada en salmónidos alrededor del mundo. Los signos clínicos y la tasa de mortalidad dependen de varios factores tales como la dosis viral, la edad del pez y la temperatura del agua, entre otros. Un estudio experimental se llevó a cabo para medir el efecto de la temperatura sobre el perfil de expresión génica de IFN-1(α), STAT-1 y Mx-1 en alevines de trucha arcoíris expuestos con IPNV. Los alevines (n=198) fueron expuestos a 8, 12 y 16°C, y se tomaron muestras durante 21 días para determinar el título viral y la expresión génica. En los primeros 11 días el mayor titulo viral se registró a 8ºC en comparación con 12 y 16. A 8°C, existió un incremento significativo en el día 4 del ARNm de Mx-1 (t-test, p<0.05), momento en que el título viral empezó a disminuir. Además conforme el título viral aumentaba, también STAT-1 y Mx-1 aumentaron (r=0.91) y (r=0.96) respectivamente. Los animales fueron capaces de recuperarse desde el día 4 de algunos de los síntomas de IPN. La enfermedad clínica se desarrolló únicamente en peces expuestos a 12°C y todos murieron entre el día 6 y 14, a pesar del incremento altamente significativo mostrado en el nivel promedio de expresión de Mx-1 a 12°C, comparados con los valores registrados a 8 y 16°C (Tukey, p<0.0001). Además los perfiles de expresión de IFN-1(α) y STAT-1 decrecieron el día 7 completamente (~0.016) y (~0.020) veces, respectivamente. El nivel de expresión promedio más alto de IFN-1(α) se registró a 16°C (Tukey, p<0.0005). Los alevines expuestos a 16°C se mostraron normales durante el experimento. IFN-1(α) posiblemente generó un efecto protector desde el día 2 cuando mostró un aumento significativo en comparación con los resultados a 8 y 12°C (t-student, p<0.0001); sin embargo, STAT-1 no fue afectado de manera significativa por la temperatura, aunque el más alto valor de expresión promedio se registró a 16°C. Nuestra investigación confirma que la expresión de genes relevantes de respuesta antiviral como IFN-1(α), STAT-1 y Mx-1 son fisiológicamente modulados por la temperatura del agua, influyendo directamente en el desarrollo de la enfermedad de IPN en trucha arcoíris.

Evaluation of a rainbow trout (Oncorhynchus mikyss) culture water recirculating system / Evaluación de un sistema de recirculación de agua para levante de trucha arcoiris (Oncorhynchus mikyss)

Objective. To evaluate a water recirculation system of rainbow trout fish culture at the recirculating laboratory of the Aquaculture Engineering Production Program of the Universidad of Nariño. Materials and Methods. There were cultured 324 rainbow trout (Oncorhynchus mikyss) fries in 12 plastic tanks of 250 L capacity in a recirculation aquaculture system which treatment system was made up by a conventional sedimentation tank, a fixed bead up flow biofilter with recycled PVC tube pieces used as carrier, and a natural degassing system; the sedimentation unit effluent was pumped to a reservoir tank by a centrifugal 2 HP after passed by gravity through the biofilter and was distributed to the 12 culture units in which there were injected a constant amount of air from a blower. Results. The waste water treatment system removes 31% of the Total Suspended Solids; 9.5% of total ammonia nitrogen, and increased the dissolved oxygen to the final effluent in a 6.5%. It was calculated a biomass increase of 305% on the 75 days, the mortality percentage registered during the research period was of 4.9%. Conclusions. The wastewater treatment system maintained the physic chemical water quality parameters in the recommended values for the specie. The values of weight and size gain, food conversion, mortality and biomass production reported were between the normal values of rainbow trout fish culture in recirculating systems.

Objetivo. Evaluar un sistema de recirculación de agua para cultivo de trucha arcoiris en el laboratorio de recirculación del Programa Ingeniería en Producción Acuícola de la Universidad de Nariño. Materiales y métodos. Se cultivaron 324 alevinos de trucha arco íris (Oncorhynchus mikyss) en 12 tanques plásticos de 250 L de capacidad en un sistema de recirculación para acuacultura cuyo sistema de tratamiento estuvo constituido por un sedimentador convencional, un biofiltro de flujo ascendente con medio soporte fijo conformado por segmentos reciclados de tubos PVC, y un sistema de desgasificación natural; el efluente del sedimentador fue elevado a un tanque reservorio por medio de una bomba centrífuga de 2 HP para después pasar por gravedad a través del biofiltro y posteriormente ser distribuido a las 12 unidades de cultivo a las que de manera permanente se inyectó aire proveniente de un blówer. Resultados. El sistema de tratamiento del agua removió 31% de los sólidos suspendidos totales; 9.5% del nitrógeno amoniacal total, e incrementó el oxígeno disuelto al efluente final en un 6.5%. Se calculó un incremento de la biomasa del 345% en los 75 días, el porcentaje de mortalidad registrado durante todo el periodo de estudio fue del 4.9%. Conclusiones. El sistema de tratamiento mantuvo los parámetros físico-químicos de la calidad de agua dentro de los rangos requeridos por la especie. El incremento de peso y talla, la conversión alimenticia, la mortalidad y la producción de biomasa reportaron valores normales para producción de trucha en sistemas de recirculación.

Composición de ácidos grasos en ovas de trucha arco iris (Oncorhynchus mykiss, Walbaum, 1792) / Fatty Acid Composition in Rainbow Trout Eggs (Oncorhynchus mykiss, Walbaum, 1792)

En este artículo se analizan con parámetros de composición 58 puestas de trucha arcoiris obtenidas, manejadas y monitoreadas individualmente en desempeño desde la fertilización hasta finalizar la etapa de reabsorción de vesícula. Además de los valores reproductivos, el contenido de ácidos grasos en las ovas se determinó en fresco, mediante cromatografía de gases. En el perfil medio se destacan los ácidos palmítico (C16), oleico (C18:1n-9) y docosahexaenoico (C22:6n-3) como los más representativos, con casi el 60% del total y, en general, en concentraciones estables entre las hembras. Tanto para cada ácido determinado como para el conjunto de contenidos integrados de las series n-3 y n-6, y los colectivos de saturados (SAF), monoinsaturados (MUFA) y poliinsaturados (PUFA), se define un patrón de composición similar al reportado para la especie en otros esquemas de manejo y bajo regímenes nutricionales variables. Se analizó la condición conservativa en la incorporación de ácidos grasos al huevo, y se discutió su utilidad como posibles definitorios de calidad, teniendo como referente la alta variabilidad registrada en la supervivencia al final del proceso de incubación...

This article analyzes, with composition parameters, 58 rainbow trout egg-layings obtained, handled and monitored individually in performance from their fertilization until the end of the gallbladder reabsortion phase. Aside from the reproductive values, the content of fatty acids in the eggs was determined in fresh conditions through gas chromatography. The average profile highlights the palmitic acid (C16), oleic acid (C18:1n-9) and docosahexaenoic acid (C22:6n-3), as the most representative, with almost 60% of the total and, in general, in stable concentrations among females. Both for each determined acid and for the suite of integrated series n-3 and n-6, and the groups of saturated (SAF), monounstaturated (MUFA) and polyunsaturated (PUFA), a pattern of similar composition to the one reported is defined for the species in other management schemes and under varying nutritional regimes. The conservative condition was analyzed in the incorporation of fatty acids into the egg and its usefulness as possible quality definers was discussed, using the high variability recorded in survival at the end of the incubation process as reference...

Neste artigo analisam-se com parâmetros de composição, 58 posturas de truta arco-íris obtidas, manejadas e monitoradas individualmente em desempenho, desde a fertilização até a finalização da etapa de absorção de vesícula. Além dos valores reprodutivos, o conteúdo de ácidos graxos nas ovas foi determinado em fresco, mediante cromatografia de gases. No perfil médio destacam-se os ácidos palmíticos (C16), oleico (C18:1n-9) e docosaexaenoico (C22:6n-3), como os mais representativos, com quase 60% do total e, em geral, em concentrações estáveis entre as fêmeas. Tanto para cada ácido determinado quanto para o conjunto de conteúdos integrados das séries n-3 e n-6, e os coletivos de saturados (SAF), monoinsaturados (MUFA) e poli-insaturados (PUFA), define-se um padrão de composição similar ao relatado para a espécie em outros esquemas de manejo e em regimes nutricionais variáveis. Analisou-se a condição conservativa na incorporação de ácidos graxos à ova, e discutiu-se sua utilidade como possíveis determinantes de qualidade, tendo como referência a alta variabilidade registrada na sobrevivência ao final do processo de incubação...

Morphological variation in a secondary contact between divergent lineages of brown trout (Salmo trutta) from the Iberian Peninsula

The aim of this study was to analyze the morphological variation of brown trout (Salmo trutta) in the Duero basin, an Atlantic river basin in the Iberian Peninsula, where a spatial segregation of two divergent lineages was previously reported, based on isozyme, microsatellite and mtDNA data. In these studies, two divergent pure regions (Pisuerga and Lower-course) and several hybrid populations between them were identified. Morphological variation was evaluated in 11 populations representative of the genetic differentiation previously observed in the Duero basin, using multivariate analysis on 12 morphometric and 4 meristic traits. A large differentiation between populations was observed (interpopulation component of variance: 41.8 percent), similar to that previously detected with allozymes and microsatellites. Morphometric differentiation was also reflected by the high classification success of pure and hybrid individuals to their respective populations, using multivariate discriminant functions (94.1 percent and 79.0 percent, respectively). All multivariate and clustering analyses performed demonstrated a strong differentiation between the pure regions. The hybrid populations, though showing large differentiation among them, evidenced an intermediate position between the pure samples. Head and body shape traits were the most discriminant among the morphometric characters, while pectoral rays and gillrakers were the most discriminant among the meristic traits. These results confirmed the high divergence of the brown trout from the Duero basin and suggest some traits on which selection could be acting to explain the spatial segregation observed.

Estandarización del manejo y la criopreservación de semen de hembras masculinizadas de trucha arco iris (Oncorhynchus mykiss) / Padronizar a gestão ea criopreservação de sêmen de fêmeas de truta arco-íris (Oncorhynchus mykiss) sob masculinização / Standardization of handling and freezing sperm from masculinized females of rainbow trout (Oncorhynchus mykiss)

La demanda de líneas monosexo hembras en la producción de trucha ha incrementado significativamente en los últimos años, por lo que se han desarrollado tecnologías para estandarizar este proceso como el uso de semen de hembras genéticas sometidas a reversión sexual. El objetivo de la presente investigación fue estandarizar la maduración in vitro y la criopreservación de semen de hembras masculinizadas (neomachos XX) de trucha arco iris (Oncorhynchus mykiss) como estrategia para producir descendencias 100% hembras de reproductores colombianos. Para la obtención del semen los neomachos fueron sacrificados y el semen recuperado fue sometido a proceso de maduración con plasma seminal de machos normales o plasma seminal artificial. Para la criopreservación del semen se probaron los crioprotectores dimetilsulfóxido 10% y metanol 10%. En el experimento se evaluron la movilidad post maduración y post descongelación y la fertilidad del semen. El proceso de maduración tuvo un efecto significativo sobre el porcentaje de movilidad (p<0.05), al obtener los mejores valores con el plasma seminal artificial (55 ± 10.4% espermatozoides móviles). Los mayores valores de movilidad postdescongelación (29.9 ± 13.3%) al igual que la mejor fertilidad (26.33 ± 7.53%), se registraron con el protocolo de dimetilsulfóxido al 10%.

The demand of monosex female stocks in production of trout has significantly increased during the past years, which has led to develop new technologies to standardize this process. The usage of semen of genetic females submitted to sexual reversion is a good choice. The objective of this research was to develop a methodology to mature in vitro and cryopreserved semen of sex-reversed rainbow trout (Oncorhynchus mykiss) females as strategy to produce lineage 100% Colombian trout female. The semen was directly obtained from the gonads after its surgical extraction of the slaughtered individuals, later it was submitted to maturation process implementing seminal plasma of normal males and artificial plasma. The semen was cryopreserved in two extender dimetyhyl sulfoxide 10% and methanol 10%. Postmaturation, postcriopreservation movility and sperm fertility were evaluated. �Maturation process had a significative effect on movility, the highest movility was obtained with artificial seminal plasma (55 ± 10.4 %). Highest post criopreservation movility (29.9 ± 13.3%) and highest fertility rates (26.33 ± 7.53 %) were obtained with dimetyhyl sulfoxide 10%.

A procura de linhas monosexo fêmeas na produção de trutas tem aumentado significativamente nos últimos anos, de modo tecnologias foram desenvolvidas com a finalidade de padronizar este processo como o uso do esperma de genética feminina submetido a reversão sexual. O objectivo do presente inquérito foi para uniformizar a maturação in vitro e criopreservação de sêmen masculinização de fêmeas (neomachos XX) trutas arco-íris (Oncorhynchus mykiss) como uma estratégia para produzir descendentes de 100% do sexo feminino dos jogadores colombianos. Para a obtenção do esperma neomachos foram mortas e sêmen foi recuperado submetida a maturação processo normal de plasma seminal plasma seminal masculina ou artificiais. Para a criopreservação de sêmen foi testado crioprotectores dimethylsulphoxide 10% e 10% de metanol. O experimento foi evaluron mobilidade pós maturação e pós descongelamento e fertilidade do sêmen. O processo de maturação teve um efeito significativo sobre a porcentagem de mobilidade (p<0.05), para obter os melhores valores com artificial seminal plasma (55 ± 10.4% esperma). Os maiores valores de mobilidade postdescongelación (29.9 ± 13.3%), bem como a melhor fertilidade (26.33 ± 7.53%), foram registrados com o protocolo de dimethylsulphoxide a 10%.

Efecto de la concentración de aflatoxina B1 y tiempo de exposición sobre la condición hepática de la trucha arcoiris / Effects of aflatoxin B1 concentration and exposure time on hepatic condition in the rainbow trout

Se determinó el efecto de la concentración y tiempo de exposición de la afla­toxina B1 (AFB1) sobre la condición hepática de la trucha arcoiris (Oncorhynchus mykiss). Se utilizaron 3600 ovas em­brionadas de 13 días postfertilización y 5,36mm de diámetro, se dividieron en lotes de 200 y se colocaron en 18 recipientes plásticos. Las concentraciones de AFB1 fueron 0,55 y 0,75ppm para el grupo experimental y 0 para el control, y el tiempo de exposición 1 y 2 horas por tratamiento y por repetición. Después de la exposición de las ovas, éstas fueron colocadas nuevamente en las incubadoras hasta la eclosión. Cada tres meses se sacrificaron 10 ejemplares por réplica, tratamiento y tiempo de exposición. Se determinaron las características macroscópicas del hígado utilizando cuatro categorías: hígado normal, pálido, con manchas y con tumores. El análisis de regresión logística determinó diferencias significativas en la condición hepática con las dos concentraciones de AFB1, no así los tiempos de exposición. Las truchas que presentaron he­pa­tomas se encontraron a los 7 (3,33 por ciento), 9 (6,67 por ciento) y 13 meses de edad (57-60 por ciento) respectivamente, con las dos concentraciones de AFB1 utilizadas

Comportamiento del consumidor de truchas en el municipio Maracaibo / Behavior of trout consumers in the Maracaibo municipality

A objeto de definir el comportamiento del consumidor de truchas del municipio Maracaibo, se realizó una investigación descriptiva no experimental de campo a los habitantes con edad comprendida entre 25 y 60 años de las Parroquias en las que existen al menos, dos puntos de ventas de truchas y se utilizó un muestreo polietápico para una muestra de 400 consumidores. Los datos se recolectaron utilizando un cuestionario y analizados con estadísticas descriptivas. Los resultados indican que el 69 por ciento de los consumidores son hombres, 70 por ciento mayor de 45 años y el 72 por ciento con nivel de ocupación profesional, el ingreso del 87 por ciento es mayor a Bs. 1.200.000, ubicando al consumidor en los estratos B y C. la percepción de los consumidores revela que el 48 por ciento consideran la frescura y el 25 por ciento el tamaño del producto fundamental para la decisión de compra, el 52 por ciento de los consumidores califican el producto de bueno a regular, 54 por ciento y 69 por ciento consideran el producto pequeño e insípido respectivamente. El gusto 39 por ciento y el hábito 28 por ciento representan el motivo principal de compra del producto. Los consumidores demandan truchas empacadas al vacío 55 por ciento y con recetarios incluidos 43 por ciento

Efectos de la incorporación en la dieta de pigmentos carotenoides: sobre el desarrollo gonadal y la madurez de los ovocitos en hembras de trucha arco iris (Onchorhynchus mykiss, Walbaum, 1972) / Effects of the dietary incorporation of carotenoid pigments: on gonad development and oocyte maturity in females of rainbow trout (Oncorhynchus mykiss, Walbaum, 1972)

Se utilizaron cuatro grupos experimentales con 60 hembras de trucha arco iris (Onchorhynchus mykiss) cada uno, con un peso promedio de 467 g, las cuales fueron sometidas a un ensayo aleatorio para comparar la eficiencia de cuatro dietas conteniendo diferentes concentraciones de pigmentos carotenoides y determinar sí la concentración y el origen del mismo presentaba una influencia sobre el desarrollo gonadal y la maduración de los ovocitos. La primera dieta fue una dieta control no pigmentada (C); la segunda contenía 100 mg kg-1 de Carofil Rosa (CR); la tercera y cuarta contenía 200 (CR200) y 250 (CR250) mg kg-1 de oleorresina saponificada de chile rojo (Capsicum annuum), respectivamente. Los resultados mostraron que existieron diferencias significativas (p £ 0.05) entre las dietas C y CR250 con respecto al índice gonadosomático (IGS), peso promedio de la gónada (PG) y el diámetro de los ovocitos (DO), presentando la última dieta los valores más altos de estos factores. Los tratamientos de CP y CR200 presentaron valores similares. Al final del experimento solamente se observó el 10 por ciento de ovocitos maduros en la dieta CR250

Determinacion de los niveles de contaminacion por Mercurio en la especie Salmo Gairdnerie Irideus y el cuerpo de agua de la Laguna Suches adyacentes al Lago Titicaca del Departamento de La Paz / Determination of the levels of contamination by mercury in the species Salmo Gairdnerie Irideus and the water body of the adjacent Suches lagoon to the titicaca lake of the department of La Paz

En el presente estudio se determino la presencia de mercurio en la especie Salmo gairdnerie irideuis (trucha) y en aguas de la Laguna Suches afluente al lago Titicaca, la cual esta situada en la reserva Ulla-Ulla. La evaluacion se realizo mediante el metodo de espectrofotometria de Absorcion Atomica por generacion de vapor frio utilizando las tecnicas de oxido, reduccion para la preparacion de muestras. En 30 muestras de peces se determina que el 100 porciento tiene de contaminacion y en 25 muestras de agua de la Laguna Suches se determina que el 100 porciento de las muestras tambien presentan contaminacion. El tamaño muestral esta limitado por la poca accesibilidad de la zona esta circundada por minas pertenecientes al sector privado. La media de contaminacion por mercurio en peces es de 0.104 ppm, en agua corresponde a 0.398 ppb. Estos valores son menores a los valores permisibles que señala la Organizacion Mundial de la Salud que son de 2 ppm. Sin embargo consideramos que los mas importante de esta investigacion no son las concentraciones que se encuentran por debajo del limite permisible, sino el haber encontrado que el equilibrio ecologico de la zona esta en un inicio de contaminacion por un metal altamente toxico como es el mercurio

Further observations on cerebellar climbing fibers. A study by means of light microscopy, confocal laser scanning microscopy and scanning and transmission electron microscopy

The intracortical pathways of climbing fibers were traced in several vertebrate cerebella using light microscopy, confocal laser scanning microscopy, scanning and transmission electron microscopy. They were identified as fine fibers up to 1(micron thick, with a characteristic crossing-over bifurcation pattern. Climbing fiber collaterals were tridimensionally visualized forming thin climbing fiber glomeruli in the granular layer. Confocal laser scanning microscopy revealed three types of collateral processes at the interface between granular and Purkinje cell layers. Scanning electron microscopy showed climbing fiber retrograde collaterals in the molecular layer. Asymmetric synaptic contacts of climbing fibers with Purkinje dendritic spines and stellate neuron dendrites were characterized by transmission electron microscopy. Correlative microscopy allowed us to obtain the basic three-dimensional morphological features of climbing fibers in several vertebrates and to show with more accuracy a higher degree of lateral collateralization of these fibers within the cerebellar cortex. The correlative microscopy approach provides new views in the cerebellar cortex information processing.

Energy interconversion by the sarcoplasmic reticulum Ca2+-ATPase: ATP hydrolysis, Ca2+ transport, ATP synthesis and heat production

The sarcoplasmic reticulum of skeletal muscle retains a membrane bound Ca2+-ATPase which is able to interconvert different forms of energy. A part of the chemical energy released during ATP hydrolysis is converted into heat and in the bibliography it is assumed that the amount of heat produced during the hydrolysis of an ATP molecule is always the same, as if the energy released during ATP cleavage were divided in two non-interchangeable parts: one would be converted into heat, and the other used for Ca2+ transport. Data obtained in our laboratory during the past three years indicate that the amount of heat released during the hydrolysis of ATP may vary between 7 and 32 Kcal/mol depending on whether or not a transmembrane Ca2+ gradient is formed across the sarcoplasmic reticulum membrane. Drugs such as heparin and dimethyl sulfoxide are able to modify the fraction of the chemical energy released during ATP hydrolysis which is used for Ca2+ transport and the fraction which is dissipated in the surrounding medium as heat.

Correlative microscopy of cerebellar Golgi cells

The cerebellar Golgi cells of mouse, teleost fish, primate and human species have been studied by means of light and Golgi light microscopic techniques, confocal laser scanning microscopy, slicing technique, ethanol-cryofracturing and freeze-fracture methods for scanning electron microscopy and ultrathin sectioning and freeze-etching replicas for transmission electron microscopy. The Golgi cells appeared in the granular layer as polygonal, stellate, round or fusiform macroneurons surrounded by the granule cell groups. They exhibited ascending dendrites toward the molecular layer and horizontal dendrites and a short beaded axonal plexus confined to the granular layer. Scanning electron microscopy revealed their three-dimensional neuronal geometry and smooth outer surfaces. Freeze-fracture method for SEM showed the stereospatial cytoplasmic arrangement of endoplasmic reticulum, cell organelles and nuclear envelope. By means of transmission electron microscopy the asymmetric synaptic connections of Golgi cell horizontal dendrites--with mossy fiber rosettes at the cerebellar glomerulus--and of Golgi cell axons--with granule cell dendrites at the periphery of glomerular region--were identified. At the molecular layer, Golgi cell ascending dendrites exhibited short neckless spines establishing asymmetric contacts with granule cell axons or parallel fibers. Shaft asymmetric axodendritic and axospinodendritic contacts between Golgi cell dendrites and climbing fibers were also found in the molecular layer.

The interaction between O2 and CO2 movements during aerobic exercise in fish

In resting rainbow trout, 99 per cent of the total CO2 excreted across the gills consisted of bicarbonate (HCO3-) dehydrated to CO2 in the red cell. This value decreased to 93 percent during exercise, the remainder being excreted as molecular CO2 which existed in the pre-branchial blood. HCO3- dehydration consumes a proton which can be supplied from hemoglobin (1-1b) through its buffer capacity or the Haldane effect. Bohr proton release from Hb upon oxygenation is maximal between 50 and 100 percent of Hb saturation, consistent with observations made in tench blood. At low swimming speeds, when venous blood 02 content (CvO2) was high, there was a small but insignificant acidosis as blood passed through the gills, indicating a greater release of protons than could be consumed by HCO3-. At higher swimming speeds, when CvO2 was low, there was a significant alkalosis in the arterial blood relative to the venous blood, indicating that fewer protons were released upon oxygenation than HCO3- ions were dehydrated to CO2. The disproportionate release of Bohr protons over the range of Hb-O2 saturation in the blood at the gills limits HCO3- dehydration during greater work loads, conserving the HCO3- buffer capacity of the blood and tissues.