ABSTRACT
ABSTRACT In this study we evaluated the inclusion of chemical silage from red tilapia viscera (Oreochromis sp.) in diets for ISA Brown line laying hens (Gallus gallus domesticus) and its influence on nutritional parameters and egg quality. A total of 56 16-week-old laying hens were randomly divided into two groups (one per diet), which in turn were subdivided into 7 groups, each with 4 birds. Eggs were collected during the first 13 weeks of laying. During this period the egg quality parameters were evaluated until week 11; the bromatological characterization of the egg was carried out in the 2nd and 4th week of laying. The results indicated that the inclusion of chemical silage in 17,18% dry matter does not result in statistically significant differences in egg quality parameters or in their bromatological composition, with respect to the control. This led to the conclusion that chemical silage can be used as an alternative to protein inputs such as fish meal and soybean cake in the diet of laying hens, without modifying the quality of the final product.
RESUMEN En este trabajo se evaluó la inclusion de ensilado químico de vísceras de tilapia roja (Oreochromis sp.) en dietas para gallinas ponedoras (Gallus gallus domesticus) de la raza Isa-Brown, y su influencia sobre parámetros nutricionales y la calidad del huevo. Se utilizó un total de 56 gallinas ponedoras de 16 semanas de edad divididas al azar en dos grupos (uno por dieta), los cuales a su vez se subdividieron en 7 grupos de 4 aves cada uno. Se les recolectó huevos durante las primeras 13 semanas de postura. Durante este periodo se realizó la evaluación de los parámetros de calidad del huevo hasta la semana 11. La caracterización bromatológica del huevo se realizo en las semanas 2 y 4, luego de haber sido puestos. Los resultados indicaron que la inclusion de ensilado químico en un 17,18% materia seca, no genera diferencias estadísticamente significativas (p < 0,05) en los parámetros de calidad del huevo ni en su composición bromatológica, con respecto al control. Esto permitió concluir que el ensilado químico puede ser usado como alternativa a insumos proteicos como harina de pescado y torta de soya en la alimentación de gallinas ponedoras, sin modificar la calidad del producto final.
Subject(s)
Animals , Silage , Chickens , Tilapia , Eggs , Food Analysis , Fish Proteins, Dietary , Birds , Viscera , Microbiological Techniques , MineralsABSTRACT
RESUMEN Introducción. En hematología, el estudio de las alteraciones de la morfología eritrocitaria contribuye con el diagnóstico de la normalidad o anormalidad de estas estructuras, sin embargo, el carácter cualitativo de los criterios diagnósticos dificulta su interpretación y alcance. Objetivo. Caracterizar los eritrocitos nucleados de tilapia roja (Oreochromis spp), en el contexto de la geometría fractal y euclidiana. Metodología. Se tomaron 50 eritrocitos nucleados de 20 extendidos de sangre de tilapia roja. Posteriormente todos los contornos del núcleo y el citoplasma de los eritrocitos fueron delineados, para superponer dos rejillas, una con el doble tamaño que la otra, para calcular mediante el método de Box Counting la dimensión fractal de cada eritrocito delineado. Adicionalmente fue calculada la superficie de estas dos partes del eritrocito. Resultados: Los resultados de este estudio revelaron que los valores de la dimensión fractal no permiten hacer comparaciones entre eritrocitos nucleados. Por su parte, la superposición de rejillas de 5x5 y 10x10 píxeles permitió observar que los valores de ocupación del citoplasma y el núcleo permiten hacer comparaciones entre los eritrocitos nucleados, junto con los valores de la superficie de estas dos partes del eritrocito nucleado. Conclusión: Los eritrocitos nucleados de tilapia roja pueden ser caracterizados mediante la medición de los valores espacios ocupados por su citoplasma y el núcleo, junto con los valores de la superficie de cada una de estas dos partes del eritrocito.
ABSTRACT Introduction. In hematology, the study of erythrocyte morphology alterations contributes to the diagnosis of normality or abnormality of these structures. However, the qualitative nature of the diagnostic criteria makes their interpretation and scope difficult. Objective. Characterize the nucleated erythrocytes of red tilapia (Oreochromis spp) in the context of fractal and Euclidean geometry. Methodology. Fifty nucleated erythrocytes were taken from twenty red tilapia blood smears. Subsequently, all the contours of the nucleus and the cytoplasm of the erythrocytes were delineated to superimpose two grids, one twice the size of the other, to calculate the fractal dimension of each delineated erythrocyte using the Box Counting method. Additionally, the surface of these two parts of the erythrocyte was calculated. Results: This study revealed that the fractal dimension values do not allow comparisons between nucleated erythrocytes. The superposition of 5x5 and 10x10 pixel grids allowed us to observe that the occupancy values of the cytoplasm and the nucleus allow comparisons between the nucleated erythrocytes, together with the values of the surface of these two parts of the nucleated erythrocyte. Conclusion: Red tilapia nucleated erythrocytes can be characterized by measuring the values of the spaces occupied by their cytoplasm and nucleus, together with the values of the surface of each of these two parts of the erythrocyte.
ABSTRACT
Aims@#This study aimed to isolate and characterize putative new probiotic with antimicrobial properties against common fish pathogens from the gut of Oreochromis spp. (red tilapia). @*Methodology and results@#A total of 28 colonies were isolated from gut of Oreochromis spp. and characterized phenotypically. Eight isolates were selected for probiotic characterization. Temperature, salinity, pH and bile salt tolerance, antibiotic susceptibility and antimicrobial test against selected fish pathogens (Aeromonas hydrophila, Edwardsiella tarda and Staphylococcus aureus subsp. aureus ATCC 25923) were conducted. Characterization studies revealed isolates suited for freshwater environment and exhibited tolerance against wide range of salinity, pH and bile salt. Isolates displayed different antibiotic susceptibility profile, with six exhibited antimicrobial properties against E. tarda. Molecular identification based on 16S rRNA gene sequencing showed 99.44%, 98.59% and 91.21% sequence similarity with Leuconostoc pseudomesenteroides strain 3832T, Leuconostoc lactis strain KCC202369T and Leuconostoc mesenteroides strain 4332T, respectively as compared to known sequence in the GenBank. When identified Leuconostoc spp. were coated on feed pellets, no major decrease in viability over 21 days of storage at 4 °C were observed, with an average of 8 log CFU/mL.@*Conclusion, significance and impact of study@#The characterized species allow further application assessment of the probiotic-supplemented tilapia feed. Host-originated Leuconostoc displayed potential antimicrobial properties against fish pathogen E. tarda. The isolates Leuconostoc is expected to provide protective effect for Oreochromis spp. against edwardsiellosis and to exert beneficial effects more efficiently as compared to commercial probiotics which are not specifically target for Oreochromis spp., thereby indirectly helping fish farmers in achieving economic sustainability and increase affordability of fish.
Subject(s)
Leuconostoc , Anti-Infective Agents , Tilapia , ProbioticsABSTRACT
Red tilapia (Oreochromis niloticus) is one of aquaculture’s most adaptive species. It is abundantly found in the wild and known to be cultured in several parts of the world. It is mainly a freshwater fish, inhabiting shallow streams, ponds, rivers and lakes but less commonly found living in brackish water. The concept of ‘waste to wealth’ has been applied widely as an alternative to waste reduction and environmental conservation. Based on these perspectives, the present study was conducted to assess possible medicinal and pharmaceutical values of the tilapia. The mice model of delayed-contact hypersensitivity test, the mice ear swelling test (MEST), was chosen for this study due to its ability to predict contact sensitization with less cost and time consumed. Four female BALB/c mice were tested in each group which included controls. Three different doses of scales powder at 500, 1000, and 2000 mg/kg in an acetone and olive oil (AOO) solution were formulated and applied to shaved dorsal trunk of the mice at induction phase, and to both sides of each ear of the mice at elicitation phase. From the observations made throughout the study period, neither erythema nor oedema was formed on the skin of mice treated with scales powder in AOO solution. Mice ear thickness increase showed percentage ear swelling of no more than 20%. Thus, the finding of this study showed that the scales of red tilapia fish did not induce allergic sensitization and could have an application in medicinal and pharmaceutical industries.
ABSTRACT
Luego de considerar el significado de las tilapias en el escenario piscícola nacional, la posibilidad de mejorar los índices de producción es un imperativo técnico y, dentro de estos, focalizar esfuerzos experimentales en la semilla resulta ser una opción estratégica. Con el fin de establecer un referente de base se utilizaron las puestas individuales de 50 hembras de tilapia roja (Oreochromis spp.) para determinar los contenidos en los huevos de proteína (%MS), extracto etéreo (%MS), energía (cal g-1) y los perfiles de ácidos grasos (%), con algunas relaciones de interés analítico. Salvo ciertas variaciones menores, los valores encontrados se ajustan a los registros disponibles para la especie en diferentes estudios, lo que sugiere que las dietas ofrecidas a los reproductores experimentales contienen los mínimos necesarios para asegurar una provisión de nutrientes y energía suficientes para los embriones y las larvas en formación. Se analiza que, como punto de partida, esta serie de datos tiene utilidad para el desarrollo de trabajos destinados a mejorar los estándares de producción de alevinos, considerando que las variaciones en la composición, que pueden ser determinadas sobre los huevos, se pueden utilizar y tienen validez como un indicativo directo de su calidad.
After considering the meaning of tilapia in the national piscicultural scenario, the possibility of improving production rates is a technical imperative and, among these, focusing experimental efforts in the seed turns out to be a strategic option. In order to establish a base model, individual laying of 50 female red tilapia (Oreochromis spp.) were used to determine the content of protein in eggs (%MS), ether extract (%DM), energy (cal g-1) and fatty acid profiles (%) with some relations of analytical interest. Except for minor variations, the values found are consistent with the available records for the species in different studies, suggesting that diets offered to experimental breeders contain the minimum necessary to ensure provision of sufficient energy and nutrients for embryos and larvae in formation. It is analyzed that, as a starting point, this series of data is useful for the development of work to improve the standards of fingerling production, considering that variations in the composition, which can be determined on the eggs, can be used and have validity as a direct indication of its quality.
Depois de considerar o significado das tilápias no cenário da piscicultura nacional, a possibilidade de melhorar los índices de produção é um imperativo técnico e, dentro destes, focalizar esforços experimentais na semente resulta ser uma opção estratégica. Com a finalidade de estabelecer um referente de base, se utilizaram as postas individuais de 50 fêmeas de tilápia vermelha (Oreochromis spp.) para determinar os conteúdos nos ovos de proteína (%MS), extrato etéreo (%MS), energia (cal g-1) e os perfis de ácidos gordurosos (%), com algumas relações de interesse analítico. Com exceção de algumas variações menores, os valores encontrados se ajustam aos registros disponíveis para a espécie em diferentes estágios, o que sugere que as dietas oferecidas aos reprodutores experimentais contêm os mínimos necessários para assegurar uma provisão de nutrientes e energia suficientes para os embriões e as larvas em formações. Analisa-se que, como ponto de partida, esta série de dados tem utilidade para o desenvolvimento de trabalhos destinados a melhorar os padrões de produção de alevinos, considerando que as variações na composição, que podem ser determinadas sobre os ovos, se podem utilizar e têm validade como um indicativo direto de sua qualidade.
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El objetivo del presente trabajo fue estimar los efectos genéticos para peso al momento de sexaje, crecimiento y sobrevivencia hasta cosecha, y proporción de mancha (área de mancha y presencia/ausencia de mancha) durante la fase comercial en un grupo de 86 familias de hermanos enteros y 31 familias de hermanos medios de tilapia roja (tilapia sp). La media de peso durante la fase de crecimiento comercial fue de 181,4 g (184 g para machos y 178 g para hembras), los machos significativamente más grandes que las hembras (P < 0,001). Las variables de sobrevivencia, área de mancha y ausencia de mancha no presentaron diferencias entre los sexos. Las heredabilidades estimadas (h²±E.S) para crecimiento comercial y sobrevivencia fueron 0,23±0,02 y 0,05±0,03, respectivamente. El porcentaje de mancha y la ausencia y presencia de la misma mostraron heredabilidades cercanas a cero, lo cual indica que estos dos caracteres están relacionados más con efectos ambientales que con efectos genéticos aditivos. Se encontró una correlación favorable y significativa entre sobrevivencia y crecimiento comercial (0,24; P < 0,05). Los resultados de este trabajo indican que mediante la explotación de la genética aditiva es posible mejorar el desempeño de los animales para crecimiento comercial y sobrevivencia en la tilapia roja, mientras que poco progreso se puede esperar por medio de la selección para variables relacionadas con el manchado corporal en la población evaluada.
The aim of this study was to quantify the genetic effects for commercial weight as, pond survival and degree of black spot for red tilapia (Tilapia ssp). A total of 86 families were evaluated, the average weight at commercial size was 181.4 g with males being significantly heavier than females. Pond survival, spotted area and presence/absence of black spots did not differ between sexes. The estimated heritabilities (h²±S.E.) for harvest weight and pond survival were 0.23±0.02 0.05±0.03, respectively. No heritability was found for spotted area and for presence/absence of black spots indicating that these traits are more affected by environmental conditions rather than by additive genes. We found a significant positive favorable correlation between harvest weight and survival (0.26; P < 0.05). The results of this study show that through selective breeding is possible to improve the performance of red tilapia for commercial growth and survival. While selection to reduce black spots in the studied population should show little progress.
ABSTRACT
To meet the increasing demand for fish, aquaculture has expanded through intensive farming that requires large amounts of feed. This can cause environmental and economic difficulties because fish can only retain 20 to 30 % of the ingested nitrogen (N). The remaining fraction is excreted as ammonium and can accumulate in water, thus becoming detrimental to fish performance. This experiment used red tilapia (Oreochromis sp) to determine the effects of temperature, body weight, and dietary crude protein (CP) on ammonium excretion. A factorial AxBxC design was used to compare total ammonium excreted. Factor A is defined as fish body weight (P). Fish weights were: P1= 100 ± 6.2, P2= 249 ± 4.2 y P3= 498 ± 4.7g. Factor B is defined as dietary protein levels (D1, D2 y D3), and factor C as water temperature (T1 and T2). Increased dietary protein levels, as well as water temperature caused significant increases in ammonium excretion (p<0.05). Body weight showed an inverse relationship with ammonia excretion. The 100 g fish at 26 ºC consuming a 25.6% CP diet excreted 468.8 ± 2.2 g N- NH4+ /day/kg, while 498 g fish under the same diet and temperature, excreted 356.3 ± 1.6 mg N- NH4+ /day/kg. This study suggests that dietary factors and environmental variables can alter ammonia excretion in fish, and thus affect of ammonia toxicity in the surrounding water.
Con el fin de atender la creciente demanda del mercado, la acuicultura se ha expandido mediante la implementación de sistemas de cultivo intensivo que requieren suministro de altas cantidades de alimento. Estas condiciones pueden generar dificultades ambientales y económicas debido a que los peces solamente pueden retener 20 a 30% del nitrógeno (N) ingerido; la proporción restante, que es excretada en la forma de amonio, se puede acumular en al agua llegando a ser perjudicial para los peces. El presente experimento fue realizado con el fin de determinar el efecto de la temperatura, peso corporal y niveles proteicos de las dietas sobre las tasas de excreción de amonio total en tilapia roja (Oreochromis sp). Para la cuantificación del amonio total se aplicó un diseño completamente al azar con arreglo factorial AxBxC, siendo el factor A = peso corporal de los peces (P1= 100 ± 6.2, P2= 249 ± 4.2 y P3= 498 ± 4.7 g), B= dietas experimentales (D1, D2 y D3) y C = temperatura del agua (T1 Y 72). El aumento de los niveles de proteína de la dieta, así como de la temperatura del agua, ocasionaron incrementos significativos en las tasas de excreción de amonio total (p<0.05). El peso corporal presentó una relación inversa respecto a la tasa de excreción de amonio. Peces de 100 g a 26 ºC y una dieta con un nivel proteico del 25.6% excretaron 468.8 ± 2.2 g N-NH4+ al día/kg de peso vivo, en tanto que peces de 498 g bajo la misma dieta y la misma temperatura, excretaron 356.3 ± 1.6 mg N-NH4+ al día/kg de peso vivo.
Para atender à crescente demanda do mercado, a aquicultura tem se expandido através da implementação de sistemas de agricultura intensiva que exigem a entrega de grandes quantidades de alimentos. Essas condições podem gerar dificuldades ambientais e económicas porque o peixe só pode conter 20 a 30% de nitrogênio (N) ingeridos, o resto é excretada na forma de amônia pode acumular-se na água tornando-se prejudicial para os peixes. Este experimento foi conduzido para determinar o efeito da temperatura, peso corporal e níveis de proteína na dieta sobre a taxa de excreção de amônia total em tilápia vermelha (Oreochromis sp.) Para a quantificação de amônia total foi aplicado um delineamento inteiramente casualizado com AxBxC factorial, sendo o factor A = peso corporal dos peixes (P1 = 100 ± 6.2, P2 = 249 ± 4.2 e P3 = 498 ± 4.7 g), B = dietas experimentais (D1, D2 e D3) e C = temperatura da água (T1 e 72). Aumento dos níveis de proteína na dieta, bem como a temperatura da água, resultou em aumentos significativos nas taxas de excreção de amônia total (p<0.05). O peso corporal mostrou uma relação inversa com a taxa de excreção de amônia. Peixes de 100 g mantidos em 26 ºC e uma dieta com teor proteico de 25.6% excretaram 468.8 ± 2.2 g de N-NH4 + por dia / kg de peso corporal, enquanto os peixes de 498 g com a mesma dieta e à mesma temperatura, excretada 356.3 ± 1.6 mg N-NH4 + por dia / kg de peso vivo.