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Made available in DSpace on 2021-06-25T10:47:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-12-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Empresa Brasileira de Pesquisa Agropecuária Antibiotics, Hematological Variables, Oxidative stress, Aquaculture; Agricultural Water Management; Environmental Science; Environmental Risk Assessment; Environmental Toxicology; Toxicology Intensive fish cultivation has a high incidence of infection, which is often controlled by administering antibiotics. Florfenicol (FF) is one of the two antimicrobial drugs permitted for aquaculture in Brazil. Due to their intensive use, potentially harmful effects on aquatic organisms are of great concern. In this sense, we investigated whether the presence of FF in cultivation water could change the health parameters of Nile tilapia. For this, we evaluated hemoglobin, hematocrit, mean corpuscular hemoglobin (MCHC) concentration, mean corpuscular volume (MCV), total plasma protein (TPP), number of circulating red blood cells and leukocytes, as lipid peroxidation levels, catalase activity and glutathione S-transferase activity of fish exposed to 11.72 mg L−1 of FF in water for 48 h. The fish were divided into two groups: Nile tilapia in water with FF or without FF (control). Exposure to FF in cultivation water for a short period didn't change the hematological variables analyzed, but caused changes in liver ROS (Reactive oxygen species) markers of the Nile tilapia, which was revealed by lipid peroxidation levels, catalase activity, and glutathione S-transferase. The 48h exposure period was enough to induce oxidative stress in hepatocytes, causing cellular oxidative damage. Therefore, the antibiotic florfenicol may cause toxicity to organisms and aquatic ecosystems, even at a sublethal concentrations near 1/100 LC50-48h for fish species. Institute of Chemistry University of Campinas, POB 6154 Joint Graduate Program in Physiological Sciences Federal University of São Carlos -UFSCar/São Paulo State University UNESP Campus Araraquara Embrapa Environment Brazilian Agricultural Research Corporation (EMBRAPA), Rod. SP 340, Km 127,5, Caixa Postal 69 Joint Graduate Program in Physiological Sciences Federal University of São Carlos -UFSCar/São Paulo State University UNESP Campus Araraquara Empresa Brasileira de Pesquisa Agropecuária: 0117020010606007

Trichlorfon [TCF] is an organophosphate compound used to eliminate or control a variety of parasites in farmed fish. The physiological and biochemical responses of juvenile Nile tilapia were studied after 96 hours of exposure to TCF. The experiment was conducted randomly with two treatments: control and TCF (0.5 mg L-1). No mortality or changes in hematological profile were recorded for the fish. On the other hand, we found that TCF exposure caused behavioral, metabolic and hormonal changes that modified the response patterns of the immune and enzymatic defense system in muscle and liver tissues. Increased plasma cortisol and glucose combined with the reduction of acetylcholinesterase activity in muscle and liver tissue after 96-h of TCF exposure indicates chemical stress. In response to this harmful situation, we observed changes in the immune system that lead to an increased number of leukocytes, thrombocytes, monocytes, lysozyme and leukocyte respiratory burst activity. Furthermore, we associate the increased activity of glutathione-S-transferase in liver tissue as a strategy fish use to combat the effects of TCF. Thus, we conclude that TCF affects the physiologic parameters of Nile tilapia, which can generate irreversible situations of recovery of the clinical condition. Such fact highlights the need to search for new compounds that could replace TCF, that have no or few adverse effects on fish species. Made available in DSpace on 2021-02-02T01:07:36Z (GMT). No. of bitstreams: 1 Ishikawa-Physiological-biochemical-2020.pdf: 411152 bytes, checksum: 3055487f2054433a3537fc309c715a16 (MD5) Previous issue date: 2020

In this study, the effect as growth promoter of five lactic acid strains (Enterococcus faecium, E. durans, Leuconostoc sp., Streptococcus sp. I and Streptococcus sp. II), isolated from intestinal tract of Nile tilapia (Oreochromis niloticus), was evaluated. Eight isocaloric diets were formulated: one containing 40% of protein as positive control, and seven with 27% protein. Five diets with 27% protein were supplemented with one of the isolated lactic acid bacteria in a concentration of 2.5x106 cfu g-1 of diet. A commercial probiotic based on S. faecium and Lactobacillus acidophilus was added at the same concentration to one 27% protein diet as a comparative diet, and the last diet was not supplemented with bacteria (negative control). Tilapia fry (280 mg basal weight) stocked in 15 L aquaria at a density of two per liter were fed for 12 weeks with experimental diets. Results showed that fry fed with native bacteria supplemented diets presented significantly higher growth and feeding performance than those fed with control diet. Treatment with Streptococcus sp. I isolated from the intestine of Tilapia produced the best growth and feeding efficiency, suggesting that this bacteria is an appropriate native growth promoter.

Os aspectos nutricionais são relevantes para otimizar a produção da tilápia-do-Nilo e redução do impacto ambiental causado pela atividade. Em função do potencial no escopo dos aspectos nutricionais, estudos precisam ser incentivados acerca da qualidade das rações comerciais, uso de extratos de plantas e adubação de viveiros com cama-de-frango, considerando a variedade de sistemas de produção, fases de desenvolvimento dos peixes, características climáticas do local de produção e condição imunológica dos animais. Portanto, o objetivo deste estudo foi avaliar a qualidade de rações comerciais para tilápiado-Nilo em crescimento; testar a incorporação do extrato aquoso de folhas de Serjania marginata na dieta da tilápia; e verificar os efeitos da adubação com cama-de-frango em viveiros no cultivo da tilápia. O estudo da qualidade de rações comerciais foi realizado com rações de dez diferentes fabricantes sendo avaliados os aspectos físicos (tamanho de péletes, flutuabilidade, estabilidade e quantidade de finos), químicos (composição centesimal, e teores de aflatoxinas e de vitamina C) e biológicos (desempenho e digestibilidade); no estudo com uso do extrato aquoso de folhas de S. marginata foram avaliados os efeitos na atividade de enzimas do metabolismo digestivo e hepático e na histopatologia do intestino e fígado; e na fertilização com cama-de-frango foram avaliados a acumulação de elementos traço (água, sedimento e filé do peixe) e o desempenho produtivo (ganho de peso e conversão alimentar). De acordo com os resultados obtidos, destaca-se que a qualidade das rações comerciais difere entre fabricantes e lotes do mesmo fabricante, além de não ser condizente em alguns casos com a qualidade esperada, de acordo com as informações do rótulo e limites estabelecidos para sua conformidade, afetando os parâmetros de desempenho (índice viscerossomático, consumo de ração, mortalidade e taxas de retenção proteica e de energia) e de digestibilidade, com base na exigência da espécie (fósforo e proteína digestíveis), além de apresentarem relações inadequadas de cálcio/fósforo e energia/proteína, digestíveis Made available in DSpace on 2019-10-02T00:43:09Z (GMT). No. of bitstreams: 1 TeseErikaOta2019.pdf: 2761786 bytes, checksum: f2da800ebc3fb86c8a098358aed129c2 (MD5) Previous issue date: 2019 Orientadora: Dra. Claudia Andréa Lima Cardoso; Coorientadora: Dra. Tarcila Souza de Castro Silva

RESUMEN:En este trabajo se estudió el proceso de extracción de colágeno a partir de tres subproductos de pescado: escamas de tilapia roja (ETR), espina dorsal de trucha (EDT) y piel de tilapia nilótica (PTN). En general, el proceso consistió en 4 etapas: desengrasado, pretratamiento alcalino, extracción ácida y filtración tangencial. Para seleccionar el mejor subproducto se compararon los rendimientos de extracción porcentuales de colágeno. El mejor subproducto resultó ser la PTN, con esta se estandarizó el proceso de extracción de colágeno mediante la implementación de diseños experimentales con el fin de establecer las condiciones óptimas del pretratamiento alcalino y de la extracción ácida mediante la metodología de superficie de respuesta. Adicionalmente se hizo un estudio cinético y se obtuvo un modelo fenomenológico (primera extracción alcalina) y varios empíricos (pretratamiento alcalino y extracción ácida) que mostraron una buena capacidad de predicción de los datos experimentales correspondientes a la concentración de la proteína no colagenada (PNC). Para el caso de la primera y segunda extracción alcalina fue posible construir un modelo general, basado en el modelo de segundo orden (MSO), que permitió estimar la concentración del soluto en términos de temperatura, tamaño de piel, concentración de NaOH y del tiempo. El modelo general fue ajustado para los 135 experimentos del diseño experimental de la primera extracción alcalina promediando un R2 de 0.99. Adicionalmente, se realizó un escalado del pretratamiento alcalino y de la extracción ácida desde 200 mL hasta 2 L. El extracto ácido de colágeno obtenido se concentró mediante un proceso de filtración tangencial, la cual se modeló usando mediante teoría fundamentada en los mecanismos de bloqueo de poro y formación de torta, con una capacidad de ajuste aceptable. Así mismo, se hicieron diafiltraciones con el fin de obtener un colágeno que cumpliera con los requerimientos de la norma técnica colombiana. Finalmente, el colágeno obtenido se liofilizó y se caracterizó, resultando ser tipo I, el cual tiene aplicaciones en el campo farmacéutico y alimentario. ABSTRACT: In this work the collagen extraction process was implemented from three fish by-products: red tilapia scales (RTS), trout dorsal spine (TDS) and nile tilapia skin (NTS). In general, the process consisted of four stages: defatted, alkaline pretreatment, acid extraction and cross flow filtration. In order to select the best by-product, the percentage yields of collagen extraction were compared and the NTS resulted be the best. Then collagen extraction process from NTS was standardized through the implementation of experimental designs in order to establish the optimal conditions of alkaline pretreatment and acid extraction using response surface methodology. Additionally, a kinetic study was carried out and a phenomenological model (first alkaline extraction) and three empirical models (alkaline pretreatment and acid extraction) were developed and they showed a good prediction of the experimental data of the non-collagenous protein (NCP) concentration. In the case of the first and second alkaline extraction it was possible to build a general model, based on the second order model (SOM) which allowed estimating the liquid concentration of NCP in terms of temperature, skin size, NaOH concentration and time. This model was fitted with 135 experiments of experimental design in the first alkaline extraction averaging a R2 of 0.99. Additionally, an alkaline pretreatment and acid extraction scaling up from 200 mL to 2 L was performed. The collagen acid extract obtained was concentrated by a cross flow filtration process, which was modeled using the theory of pore blocking and cake formation mechanisms, with a good prediction of the experimental data. Likewise, diafiltration were made in order to obtain a collagen that met the requirements of the Colombian technical standard. Ultimately, Freeze-dried collagen was analyzed by infrared spectroscopy, SEM and SDS-PAGE and it result be a type I collagen, which has applications in the pharmaceutical and food industry.

Biofloc technology system (BFT), recirculation aquaculture system (RAS) and polyculture promote efficient use of water, area and nutrient recycling, which are essential practices for sustainable aquaculture development. The aim of this study was to evaluate the growth, feed efficiency, biofloc composition and water quality of Nile tilapia Oreochromis niloticus (Linnaeus, 1758) in monoculture and polyculture with giant freshwater prawn Macrobrachium rosenbergii (De Man, 1906) in BFT and RAS, over a period of 30 days. Fish (n = 128; 7.29 ± 0.67 g) were distributed randomly in 16 experimental tanks (8 fish/tank). Prawn (n = 96; 0.50 ± 0.09 g) were allocated in 8 experimental tanks (12 prawn/tank) in a polyculture. The experimental design was completely randomized with four treatments with four replicates each, in a factorial design 2 × 2 (BFT and RAS vs. monoculture and polyculture). The experimental diet (28% of digestible protein; 3100 kcal kg−1 of digestible energy) was used both to fish and prawn in BFT and RAS. There was significant effect (p p p

Se evaluaron variables medioambientales (temperatura, oxígeno, pH) del agua en estanques, a las 6, 14, 22 horas. Las variables de producción analizadas fueron ganancia de peso (g/día/pez), consumo de alimento balanceado (pez/día/g) y conversión alimenticia. Los costos fijos representaron: mantenimiento del estanque e instalación del polímero en el piso y cubierta. Los costos variables se determinaron por el costo del alevino de Oreochromis niloticus y del alimento balanceado de 30% de proteína, evaluados en cuatro tratamientos: estanques con piso en tierra y cubierta plástica, piso en plástico y cubierta plástica, piso en plástico sin cubierta y estanques en tierra sin cubierta plástica. El plástico utilizado para la cubierta fue el Agroclear XF y para el piso de los estanques se utilizó el polímero Agroblack No. 15, utilizando un diseño en bloques completos al azar, en el tiempo y tres repeticiones por bloque. Los resultados muestran que la construcción en guadua de los invernaderos para los estanques utilizando Guadua angustifolia, es una opción económica para piscicultores, las cubiertas plásticas de los estanques permiten un control adecuado de la temperatura del agua en los estanques y controla en un 100% la depredación de peces por aves piscívoras. Se concluye que los estanques con piso en tierra y cubierta plástica fueron los más eficientes, presentaron facilidad de manejo, mayor producción de plancton, mejor rendimiento productivo y económico, que coincidió con la mayor estabilidad térmica, seguido por los estanques con piso en tierra sin cubierta plástica, convirtiéndose en una alternativa viable para optimizar la producción piscícola. Environmental variables (temperature, oxygen, pH) of the water of the ponds were evaluated at the 6, 14, and 22 hours. The production variables analyzed were weight gain (g/day/fish), consumption of balanced food (fish/day/g) and feed conversion. Fixed costs represented: pond maintenance and installation of polymer on the floor and cover. Variable costs were determined by the cost of the Oreochromis niloticus larva and 30% protein balanced feed, evaluated in four treatments: ground-floor ponds with plastic cover; plastic floor ponds and plastic cover; plastic floor ponds without cover; ground-floor ponds without plastic cover. The plastic used for the cover was Agroclear XF, and for the floor of the pond the Agroblack No. 15 polymer was used, utilizing a design in randomized complete blocks in time and three replicates per block. The results show that construction of greenhouses in guadua for ponds using Guadua angustifolia, is an economical choice for fish farmers; the plastic covers of the ponds allow adequate control of the temperature of the water in the ponds and controls 100% fish predation by piscivorous birds. It is concluded that ground-floor ponds and plastic cover were the more efficient presenting ease of use, increased production of plankton, better productive and economical yield, coinciding with a greater thermal stability, followed by the ground-floor ponds without plastic cover, making it a viable alternative to optimize fish production.

Se evaluaron variables medioambientales (temperatura, oxígeno, pH) del agua en estanques, a las 6, 14, 22 horas. Las variables de producción analizadas fueron ganancia de peso (g/día/pez), consumo de alimento balanceado (pez/día/g) y conversión alimenticia. Los costos fijos representaron: mantenimiento del estanque e instalación del polímero en el piso y cubierta. Los costos variables se determinaron por el costo del alevino deOreochromis niloticusy del alimento balanceado de 30% de proteína, evaluados en cuatro tratamientos: estanques con piso en tierra y cubierta plástica, piso en plástico y cubierta plástica, piso en plástico sin cubierta y estanques en tierra sin cubierta plástica. El plástico utilizado para la cubierta fue elAgroclearXF y para el piso de los estanques se utilizó el polímeroAgroblack No. 15, utilizando un diseño en bloques completos al azar, en el tiempo y tres repeticiones por bloque. Los resultados muestran que la construcción en guadua de los invernaderos para los estanques utilizandoGuadua angustifolia, es una opción económica para piscicultores, las cubiertas plásticas de los estanques permiten un control adecuado de la temperatura del agua en los estanques y controla en un 100% la depredación de peces por aves piscívoras. Se concluye que los estanques con piso en tierra y cubierta plástica fueron los más eficientes, presentaron facilidad de manejo, mayor producción de plancton, mejor rendimiento productivo y económico, que coincidió con la mayor estabilidad térmica, seguido por los estanques con piso en tierra sin cubierta plástica, convirtiéndose en una alternativa viable para optimizar la producción piscícola. Environmental variables (temperature, oxygen, pH) of the water of the ponds were evaluated at the 6, 14, and 22 hours. The production variables analyzed were weight gain (g/day/fish), consumption of balanced food (fish/day/g) and feed conversion. Fixed costs represented: pond maintenance and installation of polymer on the floor and cover. Variable costs were determined by the cost of theOreochromis niloticuslarva and 30% protein balanced feed, evaluated in four treatments: ground-floor ponds with plastic cover; plastic floor ponds and plastic cover; plastic floor ponds without cover; ground-floor ponds without plastic cover. The plastic used for the cover wasAgroclearXF, and for the floor of the pond the Agroblack No. 15 polymer was used, utilizing a design in randomized complete blocks in time and three replicates per block. The results show that construction of greenhouses in guadua for ponds usingGuadua angustifolia, is an economical choice for fish farmers; the plastic covers of the ponds allow adequate control of the temperature of the water in the ponds and controls 100% fish predation by piscivorous birds. It is concluded that ground-floor ponds and plastic cover were the more efficient presenting ease of use, increased production of plankton, better productive and economical yield, coinciding with a greater thermal stability, followed by the ground-floor ponds without plastic cover, making it a viable alternative to optimize fish production.

O objetivo deste trabalho foi o de avaliar o efeito da suplementação da dieta de Tilápias (Oreochromis niloticus) utilizando sal comercial composto dos microminerais cobre, manganês e zinco, sobre a histologia e o desenvolvimento das gônadas dos machos. Foram utilizados 1200 machos masculinizados de tilápia, com média de peso de 120g, suplementadas com níveis crescentes (0,00; 0,35; 0,70; 1,05; 1,40 e 1,75 mg/kg) de um produto comercial composto por Cu 13,40 g/kg; Mn 26,70 g/kg e Zn 66,70 g/kg. O experimento foi conduzido em um sistema de recirculação de água, composto por 24 tanques divididos ao meio totalizando 48 unidades experimentais. O delineamento experimental foi inteiramente casualizado, com medidas repetidas no tempo. As biometrias e coletas foram realizadas em 16 e 32 semanas de experimento, para avaliar o desenvolvimento dos peixes. As gônadas coletadas foram preparadas e cortadas para confecção de lamina histológica, após coradas com hematoxilina e eosina, e posteriormente fotografadas, utilizando microscópio com câmera acoplada. A contagem das fotos foi realizada manualmente, e avaliou-se o número de células por mm3, para espermatogônias, espermatócitos, espermátides e espermatozoides. As correlações entre número de espermatozoides, espermatócitos, espermátides e tratamentos foi de -0,30, -0,20 e -0,30, respectivamente, demonstrando que o efeito da suplementação crescente com o sal, é prejudicial para o desenvolvimento das células reprodutivas masculinas. Foi observado que os tratamentos com adição igual ou superior a 0,70 mg/kg do sal comercial causaram danos as gônadas para os parâmetros da gametogênese de número de espermatócitos, espermátides e espermatozoides. Sendo assim, a utilização de sais que contenham combinação de Cu 13,40 g/kg; Mn 26,70 g/kg e Zn 66,70 g/kg reprodutores machos de tilápia, não é recomendada em função dos danos causados nas etapas da gametogênese, reduzindo a produção de espermatozoides. The objective of this study was to evaluate the effect of supplementing the diet of tilapia (Oreochromis niloticus) using commercial salt compound of micro minerals copper, manganese and zinc, on the histology and gonadal development of males. A total of 1200 masculinized male tilapia were used, with 120 g average weight, supplemented with increasing levels (0.00, 0.35, 0.70, 1.05, 1.40 and 1.75 mg / kg) of a product commercial composed of Cu 13,40 g/kg; Mn 26,70 g/kg e Zn 66,70 g/kg. The trial was conducted in a water recirculation system, consisting of 24 tanks divided in half, totaling 48 experimental units. The experimental design was completely randomized with repeated measures over time. The biometry and samples were taken at 16 and 32 weeks of experiment, to evaluate the fish development. The collected gonads were prepared and sliced for making histological slide, after stained with hematoxylin and eosin, and then photographed using a microscope with attached camera. The count of the photos was performed manually, and was rated the number of cells per mm3 to spermatogonia, spermatocytes, spermatids and sperm cell. The correlations between the number of spermatozoa, spermatocytes, spermatids and treatments was of -0.30, -0.20 and -0.30, respectively, demonstrating that the effect of increasing supplementation of the salt is detrimental to the development of male reproductive cells. It was observed that the addition equal or superior to 0.70 mg / kg of commercial salt caused damage in the gonads for gametogenesis parameters number of spermatocytes, spermatids and sperma cell. Thus, the use of combination of salts containing 13.40 g Cu / kg; Mn 26.70 g / kg Zn and 66.70 g / kg breeding male tilapia is not recommended due to the damage caused in the stages of gametogenesis, reducing the sperm production.

Two scarabs from Orgame/ Argamum. The two faience scarabs discovered at Orgame in a house dated, on the basis of a stamped amphora fragment and other fine wares, to the end of the IVth century BC are of the "Naucratite type" (Gorton 1996, type XXVIII). For the ICEM 46773, a mould representing the Scarabaeus Sacer in a naturalistic way has been used ; the Tilapia Nilotica, with a Nymphaea Caerulea in its mouth, cast on the underside, is very common on scarabs : the fish which guides and protects Rê against Apophis and which spits its own alevins, like Atoum the Creator, associated with a lotus bloom, the flower of the beginnings and of the "Gott auf der Blume" , is a strong symbol of renewal and resurrection. The ICEM 46774, cast with a simplified mould into an inferior faience, has on its backside the name of Amon, joining up, in cryptographic form, the forces of Maât, Horus and Rê, just like some other scarabs from Olbia, Carthage or Egypt, found in VIth-Vth centuries layers. These amulets, preserved during generations or made and exported at a later date than usually accepted, could fill a gap in our knowledge of the (in) direct relations between the southern and northern parts of the eastern Mediterranean in the classical period., Lors des campagnes archéologiques organisées en 1998 et en 2000 dans la colonie grecque d’Orgamè, sur le littoral occidental du Pont-Euxin, deux scarabées en faïence (appartenant au type XXVIII, «naucratite», de Gorton) ont été trouvés dans une maison datée de la fin du IVe s. av. J.-C. Le premier (ICEM 46773) a été modelé dans un moule représentant d’une manière soignée le Scarabeus Sacer et porte, sur sa base, une impression représentant une Tilapia Nilotica avec une Nymphaea Caerulea. Ce motif est très fréquent sur les scarabées : le poisson qui guide et qui protège Rê contre Apophis et qui crache ses propres alevins, comme l’avait fait Atoum lui-même, associé à la fleur de lotus, marque des commencements et du «Gott auf der Blume», est un fort symbole de la renaissance. Le deuxième scarabée (ICEM 46774), réalisé avec un moule simplifié dans une faïence de qualité inférieure, porte sur sa base le nom d’Amon symbolisé, en écriture cryptographique, par les signes de Maât, de Horus et de Rê. Plusieurs parallèles ont été trouvées à Olbia, à Carthage et en Égypte, dans des contextes du VIe-Ve siècle av. J.-C. Ces amulettes égyptiennes transposées en contexte grec ou grec barbarisé, conservées pendant plusieurs générations ou exportées à une date plus tardive que celle généralement acceptée par les spécialistes, peuvent compléter notre connaissance des relations (in) directes entre les extrémités septentrionale et méridionale de la Méditerranée classique., Dan Anca. Deux scarabées d’Orgamè/Argamum. In: Dialogues d'histoire ancienne, vol. 37, n°1, 2011. pp. 9-40.

El presente estudio tuvo como objetivo evaluar la eficiencia de un sistema de recirculación cerrado en los parámetros de calidad de agua como oxígeno disuelto, pH, amoniaco, nitritos y parámetros de crecimiento de alevines de tilapia nilótica (Oreochromis niloticus) como ganancia de peso, tasa de crecimiento absoluto, tasa de crecimiento especifico TCE %/día, conversión alimentaria y coeficiente térmico de crecimiento , para lo cual se diseñó 2 tratamientos con 3 repeticiones cada ,uno T1 (40 peces/100L agua) y T2 (30 peces/100 L de agua), haciendo un total de 6 unidades experimentales con sistemas de recirculación, los flujos de agua a la entrada en cada unidad experimental fue de 250 L por hora. La temperatura del agua en las unidades experimentales se mantuvo entre 23,5± o e a 24,5 o e, el oxígeno disuelto entre 7,54±0.21 y 7,73±0,31 mg de 02/L de agua; el pH entre 7,23±1,0,34 a 7,58±0,35; el amoniaco entre 0,21 a 0,30±0,02 mg/L,Ios nitritos entre 0,36 ± 0,03 y 0,39±0,042 mg/L respectivamente, no registrándose diferencia significativa entre los parámetros físico químicos de los dos tratamientos, se les alimento con una tasa alimenticia de 15% al inicio terminado con una tasa de 3% de acuerdo al aumento de peso; se midieron y pesaron los peces al inicio y cada 30 días durante 180 días, obteniéndose los siguientes resultados: Peso final T1 77,31±2,30 g; T2 78,31±2,60 g; La tasa de crecimiento absoluto para el tratamiento T1 0,44±0,05 g; para el tratamiento T2 de 0,47±0,04. g; no encontrándose diferencia significativa entre estos parámetros; La tasa de crecimiento específico para el tratamiento T1 fue de 2,09±0,30 %/día para el tratamiento T2 fue de 2,49±0,45 %/día ; La conversión alimentaria para el tratamiento T1 fue de 1.,24 y el tratamiento T2 de 1 ,21 ±0,27 ; El coeficiente térmico de crecimiento para el T1 fue de 0.0882 ± 0.005 y para el T2 fue de 0.0892 ± 0.004; El factor de condición para T1 fue de 1.51 ± 0.42 y para el T2 fue de 1.50 ± 0.22, no encontrándose diferencia significativas (P>0,05) entre los parámetros de cultivo concluyendo que los sistemas de recirculación se puede, trabajar con altas densidades de peces por metro cúbico sin bajar significativamente los parámetros productivos en el cultivo de tilapia nilotica.

Six enzyme systems coding for 10 loci and 6 proteins were examined in the blood of Polypterus senegalus, Clarias lazera, Tilapia nilotica and Protopterus annectens, using electrophoresis. Six loci were polymorphic in all the four species, three polymorphic in three species and one polymorphic in T. nilotica. Four protein loci were monomorphic in all the four species with variants in P. senegalus and T. nilotica. Haemoglobin can be used as a species-specific marker. Polymorphism was 53-56 per cent and average heterozygosity was 0.1-0.15.

In this study a method for evaluating phenotypic sex in Nile tilapia was validated. A technique that uses aceto-carmine squash mounts to stain the entire gonadal tissue for microscopic examination (Method 2- squash mounts) was compared with a technique based on traditional histology. Approximately 2600 Nile tilapia fry weighing and measuring, respectively, between 0.25-2.50g and 26-53mm, aged 35 to 60 days after hatch (DAH), were sexed using this methodology. In situ microscopic examination on the gonads was also performed. A reliable sexing using squash mount was possible with fish weighing more than 0.500g, 45-47 DAH. Results from microscopic observation using the aceto-carmine stain coincided 100% with the histological examination. Male gonadal tissue was characterized by the presence of cysts containing spermatogonia and spermatocytes, while females were easily identified by the presence of oocytes at the perinucleolar stage. The technique proved to be efficient not only in terms of evaluating sex proportion in fish but also because it allows immediate evaluation of gonadal sex and demands less time and labour.Neste estudo foi validado um método para avaliar o sexo fenotípico de alevinos de tilápia nilótica. Foi comparada uma técnica que usa aceto-carmim para corar o tecido gonadal, o qual é examinado em microscópio, com a histologia tradicional. Aproximadamente 2600 alevinos de tilápia nilótica com idade entre 35 e 60 dias após a eclosão (DAE), pesando e medindo, respectivamente, 0,250-2,50g and 26-53mm foram sexados usando este método. Foi também realizado um exame macroscópico das gonadas in situ. Foi possivel sexar com acerto, usando o método de aceto-carmim, alevinos com peso superior a 0.50g, 45-47 DAE. Os resultados das observações microscópicas usando o corante aceto-carmim coincidiram em 100% com o exame histológico. O tecido gonadal dos machos foi caracterizado pela presenca de cistos que continham espermatogônias e espermatócitos, enquanto que as fêmeas foram facilmente identificadas pela presenca de ovócitos no estádio perinucleolar. A técnica provou ser eficiente não só para avaliar a proporção dos sexos, mas também porque permite avaliação imediata do sexo gonadal e demanda menos tempo e trabalho.

La acuicultura es una alternativa para la producción de proteína de alta calidad a bajo precio, particularmente en países en desarrollo y desabasto de alimentos. En zonas rurales, la disponibilidad de insumos alternativos es clave para mejorar la producción en el cultivo de peces, sobre todo si dichos insumos se usan en forma cruda. Una opción son las hojas de chaya (Cnidoscolus chayamansa), arbusto que crece en México, Centroamérica y Sudamérica. En este estudio se evaluó durante dos épocas climáticas (cálida y fría) la supervivencia, tasa de crecimiento y tasa de conversión alimenticia de juveniles de tilapia (7-4,5 g), al sustituir parcialmente la ración de alimento balanceado (25 y 50%) con hojas crudas de chaya (ad libitum), en un diseno experimental completamente al azar, con dos tratamientos y un control (00% de la ración a base de alimento balanceado), con tres réplicas cada uno por época climática. Las densidades fueron de 36 peces m-3 por réplica en la época fría y de 44 peces m-3 por réplica en la época cálida. Los resultados indican que los tratamientos con 50 y 75% de alimento balanceado y chaya, en ambas épocas climáticas, tuvieron una ganancia de peso similar a la de los organismos que se alimentaron con la dieta control. Durante la época fría se observaron efectos adversos en la supervivencia, peso ganado y tasa de conversión alimenticia en todos los tratamientos, lo cual no ocurrió en la época cálida. Al incluir hojas de chaya en la dieta de las tilapias, la tasa de conversión alimenticia de alimento balanceado se redujo de 9,7 a 33,62% en la época fría y de 5,38 a 40,23% en la época cálida. Los resultados muestran que el uso de insumos complementarios disponibles regionalmente como la chaya, puede favorecer el desarrollo de cultivos de tilapia a pequena escala en los trópicos. Aquaculture is an alternative for the production of high-quality, low-cost protein, particularly in developing countries with a limited food supply. In rural areas, the availability of alternative inputs is key to improving fish farming production, especially if these inputs are unprocessed. The leaves of tree spinach (Cnidoscolus chayamansa), a bush that grows in Mexico and Central and South America, are one such option. In this work, juvenile tilapia (7-4.5 g) survival, growth rates, and food conversion rates were studied during two seasons (warm and cold), substituting 25 and 50% of the balanced feed rations with raw tree spinach leaves (ad libitum). The experimental design was completely random, with two treatments and one control (00% of the balanced feed ration); three replicates were done in each season. The densities were 36 fish m-per replica in the cold season and 44 fish m-3 per replica in the warm season. The weight gain in the treatments with 50 and 75% balanced feed and tree spinach leaves was similar to that of the control group in both seasons. The cold season adversely affected survival, weight gain, and feed conversion rates in all treatments, but the warm season did not. When tree spinach leaves were included in the tilapia diet, the feed conversion rate for the balanced feed was reduced from 9.7 to 33.62% in the cold season and from 5.38 to 40.23% in the warm season. The results show that the use of locally available complementary inputs such as tree spinach leaves may favor the development of small-scale tilapia cultures in the tropics.

The aim of the present study is the environmental impact assessment of tilapia (Tilapia nilotica) farming project in brackish water of Bafgh, with goals to achieve localization of technology and knowledge of tilapia fish production, employment and the possibility to controlled development in other areas. Desired range, located in northwest of Daranjir desert (Inland Salt Water Fishes Research Station, Bafgh). Total area used for the project includes three indoor hall for breeding operation, nursery (juvenile breeding) and fattening. Besides these, three 3000 m 3 available earth ponds has been considered as a potential area breeding after setting apart the quarantine. In order to achieve sustainable development of breeding this fish, impact assessment of this project development in which both environmental and social - economic effects are considered, it seems essential and project will be accomplished more confidently. So, after considering the technical characteristics of the project, the immediate, direct and indirect impact area were determined and environmental aspects of area identified. Matrix methods was utilized for the environmental impact assessment. The most important operational activities, including greenhouse structures implementation and water conveyance facilities, including excavation and embankment, channel, piping, lining of channels and their accessories including inlet and outlet valves, concrete, stone, porcelain, walling up , roof, construction of drainage network and access roads. Based on investigation, accessibility of the region, compatibility with the other land uses, lack of monuments in the area, not covered with the sensitive habitats range, the lack of permanent river flow, low quality of underground water and end up underground water flows in downstream desert and evaporated which result in impossibility of escaping introduced fish from the farm and the use of existing spaces in the first half of the year to product lead to make fewer infrastructure costs and increase revenue, are the main criteria for the sustainable development of this species culture in the area. Considering the executed studies and results of the matrix assessment construction and operation phases, it was concluded that there is no considerable destructive impacts related to the project. Therefore due to the fact that 50% of means in rows and columns of the matrix were not less than -3.1 so, we proposed execution of it with rehabilitation plans. Therefore, some strategies and plans to consider reducing the negative effects and enhance positive effects of the project, including monitoring programs, were proposed.

"La acuicultura es una alternativa para la producción de proteína de alta calidad a bajo precio, particularmente en países en desarrollo y desabasto de alimentos. En zonas rurales, la disponibilidad de insumos alternativos es clave para mejorar la producción en el cultivo de peces, sobre todo si dichos insumos se usan en forma cruda. Una opción son las hojas de chaya (Cnidoscolus chayamansa), arbusto que crece en México, Centroamérica y Sudamérica. En este estudio se evaluó durante dos épocas climáticas (cálida y fría) la supervivencia, tasa de crecimiento y tasa de conversión alimenticia de juveniles de tilapia (7-14,5 g), al sustituir parcialmente la ración de alimento balanceado (25 y 50%) con hojas crudas de chaya (ad libitum), en un diseño experimental completamente al azar, con dos tratamientos y un control (100% de la ración a base de alimento balanceado), con tres réplicas cada uno por época climática. Las densidades fueron de 36 peces m-3 por réplica en la época fría y de 44 peces m-3 por réplica en la época cálida. Los resultados indican que los tratamientos con 50 y 75% de alimento balanceado y chaya, en ambas épocas climáticas, tuvieron una ganancia de peso similar a la de los organismos que se alimentaron con la dieta control. Durante la época fría se observaron efectos adversos en la supervivencia, peso ganado y tasa de conversión alimenticia en todos los tratamientos, lo cual no ocurrió en la época cálida. Al incluir hojas de chaya en la dieta de las tilapias, la tasa de conversión alimenticia de alimento balanceado se redujo de 9,17 a 33,62% en la época fría y de 15,38 a 40,23% en la época cálida. Los resultados muestran que el uso de insumos complementarios disponibles regionalmente como la chaya, puede favorecer el desarrollo de cultivos de tilapia a pequeña escala en los trópicos."

Com a finalidade de organizar um programa de controle da reprodução de tilápia nilótica (Oreochromis niloticus) em laboratório, foi desenvolvida uma técnica na qual foi utilizada pérolas de cerâmica presas à musculatura dorsal do animal por transfixação com um fio sintético flexível. Foram usados 60 peixes com peso médio de 12g e 60 com peso médio de 19g. A marcação foi feita em três posições: frontal (F), mediana (M) e caudal (C). Diferentes combinações de três pérolas coloridas foram fixadas do lado direito (definindo o número), e eram ligadas a uma única pérola do lado esquerdo (definido o sexo), deixando-se cerca de 1,5cm de folga no fio para não causar prejuízo ao crescimento. Os animais foram identificados e pesados individualmente aos 30, 60 e 130 dias após a cirurgia de transfixação. Os resultados indicaram que as posições F e M permitiram crescimento e comportamento reprodutivo normais, e na posição C houve mortalidade e perda do marcador. Recomenda-se como melhor posição a M, ou então a intermediária entre F e M. With the goal of organizing a control program of Nile tilapia (Oreochromis niloticus) reproduction in laboratory, a tecnique with ceramic pearls held on dorsal musculature by transfixion with flexible sintetic string was developed. Sixty fishes with 12g average weight and 60 with 19g average weight were used. Marking was done on three positions: frontal (F), median (M), and caudal (C). Different combinations of three collored pearls were fixed on the right side (defining number), and were linked to only one pearl in the left side (defining sex), with a slack of about 1.5cm to prevent growth damage. The animals were individually identified and weigthed at 30, 60 and 130 days after surgery. Results showed that both F and M positions allowed normal growth and reproductive behavior, whereas the C position induced mortality and loss of marker in some specimens. The M position is recomended as the best, or the intermediate between F and M positions.

Eugenia uniflora L. (Myrtaceae) é uma planta que ocorre no bioma Cerrado e é utilizada popularmente no tratamento de diarréias, inflamações, hiperglicemia e hipertensão. Estudos prévios revelaram atividade antimicrobiana da E. uniflora in vitro. Tendo em vista o uso popular, este trabalho objetivou avaliar as possíveis atividades celulares e teciduais sistêmicas do extrato bruto e das frações das folhas dessa planta em brânquias de Oreochromis niloticus L. (tilápia nilótica). Para isso, o extrato etanólico e as frações das folhas dessa planta foram administrados no peixe, por via oral, adicionadas à ração. Após um período de 24 horas, os peixes foram sacrificados e o segundo arco branquial de cada peixe foi dissecado, fixado em formalina neutra, desidratado, incluído em parafina e cortado. Nas análises histológicas, utilizaram-se tricômico de Masson e hematoxilina e eosina (HE). Pelas análises qualitativas na microscopia de luz, concluiu-se que o extrato etanólico bruto e as frações das folhas da E. uniflora apresentaram efeito sistêmico nas tilápias nilóticas atingindo as brânquias. As ações tóxicas como destacamento e descamação do epitélio respiratório e hiperplasia das células do epitélio interlamelar, foram mais pronunciadas nas tilápias que ingeriram maiores concentrações. Este trabalho colaborou para identificar o efeito vasodilatador dessa planta, e contribuiu para estabelecer a tilápia nilótica como sistema-modelo para testes com princípios ativos de plantas. Espera-se, com esses testes, viabilizar o uso de plantas como medicamentos para tratamentos de peixes, a manutenção da saúde de animais em cultivo intensivo e extensivo, a partir do qual se possibilite emprego alternativo aos medicamentos sintéticos. Eugenia uniflora L. (Myrtaceae) is a plant found in the Cerrado biome and traditionally used in the treatment of diarrheas, inflammations, hyperglycemia and hypertension. Previous studies have revealed in vitro antimicrobial activity of E. uniflora. Considering its popular use, this study aimed to assess possible systemic cellular and tissue activities of the crude extract and the fractions from the leaves of this plant on Oreochromis niloticus L. (Nile tilapia) gill. Thus, ethanol extract and fractions from the leaves of this plant were orally administered to the fish in their rations. After 24 hours, the fish were sacrificed and the second gill arch of each fish was dissected, fixed in neutral formalin, dehydrated, embedded in paraffin and sectioned. Masson's trichome and hematoxylin and eosin (HE) were used in the histological analyses. Qualitative analyses using a light microscope led to the conclusion that the crude ethanol extract and the fractions from E. uniflora leaves presented systemic effect on Nile tilapias, affecting the gills. Toxic actions such as respiratory epithelium detachment and lifting, and hyperplasia of interlamellar epithelial cells were more pronounced in the tilapias that ingested higher concentrations. This study helped to identify the vasodilator effect of this plant and contributed to the definition of the Nile tilapia as a model system for testing plant active principles. These tests are expected to make feasible not only the use of plants as fish medication but also the maintenance of the health of animals in intensive and extensive cultures through the possible use of alternatives to synthetic medication.

Este estudio evaluó el efecto del procesamiento de alimento (extruido frente a peletizado) sobre el desempeño productivo de tilapia nilótica durante un ciclo comercial de producción. Se utilizaron 504 alevinos reversados que fueron alimentados con un sistema de alimentación por fases (alevinaje, crecimiento 1, crecimiento 2 y finalización) con niveles de proteína cruda para cada fase de 43,10%, 36,40%, 31,50% y 28,65% respectivamente. Las dietas fueron procesadas (extruidas o peletizadas) en micro extrusora para laboratorio exteec® (exteec máquinas, Brasil). El análisis de los indicadores acumulados mostró que el proceso de extrusión generó un mayor crecimiento y una mayor eficiencia en el uso de alimento hasta la fase de crecimiento 2 (P