Estimativa da concentração espermática do sêmen de peixe pelo método de espermatócrito

Um experimento foi realizado com o objetivo de estimar a concentração espermática das espécies dourado (Salminus brasiliensis), curimba (Prochilodus lineatus), jundiá (Rhamdia quelen), cascudo-preto (Rhinelepis aspera) e tilápia-do-nilo (Oreochromis niloticus) pelo método de espermatócrito. Utilizaram-se 19, 58, 51, 43 e 85 reprodutores de dourado, curimba, jundiá, cascudo-preto e tilápia-do-nilo, respectivamente. Com exceção da tilápia-do-nilo, os reprodutores foram submetidos ao processo de indução hormonal e posteriormente submetidos a coleta de sêmen. Foram comparadas as técnicas de mensuração da concentração espermática do sêmen por contagem em câmara hematimétrica de Neubauer e por espermatócrito. Os resultados obtidos foram submetidos à análise de regressão a 5% de probabilidade. As concentrações espermáticas mensuradas por ambas as técnicas apresentaram relação linear, para curimbas, jundiás e tilápias-do-nilo, com equações y = 6,6624 × 10(9) + 3,68553 × 10(8)x; y = 2,153 × 10(9) + 4,426 × 10(8)x e y = -9,0897 × 10(8) + 6,0167 × 10(8), respectivamente. O método de espermatócrito pode ser utilizado para estimar a concentração espermática do sêmen de curimbas, jundiás e tilápias-do-nilo.

Metodologia para quantificação de leucóciotos totais em peixe Oreochromis Niloticus

Haematological investigation is an important part of disease diagnosis. The techniques used for mammals are generally applicable for fishes with slight modification. The presence of nucleated erythrocytes and thrombocytes in fish may cause some confusion in the identification of blood cells, mainly in total leukocytes count. This work evaluated two different methods (direct and indirect) of leukocytes counting. Specimens of tilapia were divided randomly into four groups of 48 fish each. Each group was further randomized into three replicate experiments of 16 fish per replicate in 40 L aquarium and maintained for 10 days. Counting of leukocytes in peripheral blood was determined in six fishes per group at the times: 0, 3, 7 and 10 days. The direct method in Neubauer chamber showed a large dispersion of data in regard to the average, the opposite was observed in indirect method determined in blood smears that showed more homogeneity among groups. Due to this factor the indirect method can be considered more accurate than the direct method for counting leukocytes in fishes.

Parâmetros do estresse oxidativo no soro de cães alimentados com rações suplementadas com óleo de caju, óleo de mamona e óleo de peixe

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Níveis de cálcio e fósforo disponíveis no desempenho reprodutiv e mineralização possea da tilápia-do-Nilo

Pós-graduação em Zootecnia - FMVZ

Valor nutritivo, pela Tilápia do Nilo, do farelo de algodão suplementado com fitase

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

As interferências das pisciculturas em tanques-rede a assembléia de peixe em grandes reservatórios do rio paranapanema (Bacia doAlto Paraná)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Substituição da farinha de peixe por farinha de vísceras de aves na alimentação do piavuçu Leporinus macrocephalus

The present study aimed at evaluating the productive performance of Leporinus macrocephalus fed with different levels of inclusion of poultry viscera meal replacing fish meal. The experiment was conducted in a stove located in the Universidade Estadual do Oeste do Paraná during 45 days. We used 200 fish with average initial length of 4.7 ± 0.37 cm and average initial weight of 1.407 ± 0.03 g, distributed in 20 net-cages. The experimental design was randomized with five treatments and five replicates with five levels of replacement of fish meal by poultry viscera meal (0, 25, 50, 75, 100%). The parameters evaluated were the productive performance and the chemical composition of animals. The inclusion of poultry viscera meal in the substitution of fish meal in the feeding of Leporinus macrocephalus can be used without impairing the performance of the animals.

Use of mathematical models in the study of bodily growth in GIFT strain Nile tilapia

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Efeito da suplementação dietética com triptofano no comportamento agressivo em juvenis de tilápia-do-Nilo

Níveis elevados de agressividade estão diretamente relacionados ao crescimento heterogêneo e ao canibalismo, podendo levar a perdas significativas na produção no setor da aquicultura. Uma alternativa para redução da agressividade poderia ser o aumento da produção de serotonina por meio da suplementação dietética com o aminoácido triptofano (TRP). A serotonina é um neurotransmissor que regula diversos processos comportamentais, dentre eles, a agressividade e o estresse. Assim, neste estudo avaliamos o efeito da suplementação dietética com triptofano TRP no comportamento agressivo em juvenis de tilápia-do-Nilo. Os peixes foram mantidos em aquários individuais durante sete dias e alimentados uma vez ao dia “ad libitum” com as dietas: T1(controle: 0,32% de TRP), T2 (1,28% de TRP) e T3 (2,56% de TRP). O índice de agressividade foi avaliado com base na resposta do peixe à sua imagem no espelho. Contabilizamos o número de ataques (mordidas) à imagem de um espelho posicionado em uma das laterais do aquário durante vinte minutos. Os peixes alimentados com T3 apresentaram menor frequência de mordidas (P = 0,010849) durante o período de observação, em comparação ao grupo controle. Concluímos que a dieta contendo 25,6mg/g TRP altera a agressividade em juvenis de tilápia-do-Nilo e que a rações suplementadas com TRP podem ser uma estratégia eficiente no manejo de pisciculturas. Também avaliamos os efeitos do TRP exógeno na ansiedade (teste do objeto novo) e estresse (teste do confinamento) em juvenis da tilápia-do-Nilo, porém não houve diferenças significativas entre os tratamentos

Integrated multi-trophic culture of Nile tilapia (Oreochromis niloticus) and Amazon river prawn (Macrobrachium amazonicum) in brackish water

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Perfil hematológico de tilápias-do-nilo alimentadas com dietas contendo diferentes lipídeos e estimuladas por baixa temperatura

The goal of this paper was to determine the effects of seven diets with differents fatty acids sources in hematology of Nile tilapia before and after cold stimulus. Seven diets, with 3% of fatty acid source, were formulated: soybean oil (OS); fish oil (OP); beef tallow (SB) and mixtures of OS+OP; OS+SB; OP+SB e OS+OP+SB. Fish (112 male of Nile tilapia of 30,0 +/- 2,65g) were totally randomly distributed, with four replicates, into 28 plastic aquaria (40 L; 4 fish per aquarium). Fish were fed four times per day for 35 days. At 35th day and also after seven days cold stimulus blood was collected and the profile hematological was evaluated. Leucocytes numbers were reduced in fish fed a SB and fish oil combination diet and were highest in fish fed SB diet before cold stimulus. Plasma protein was reduced in fish fed soybean oil diets and highest in fishes fed a combination of soybean oil, fish oil and SB diets. Anything fatty acids source promotes effective changes in fish health and cold tolerance promotion. Cold don't drastically reduced fish general health status.

Ectoparasites of Nile tilapia (Oreochromis niloticus) in cage farming in a hydroelectric reservoir in Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Deposition of bodily chemical components in the carcass of tilapia (oreochromis sp.) strains

The knowledge of how animals deposited chemical components as water, protein, fat and ash in the carcass is importance for the formulation of a balanced diet, allowing maximum performance with a low environmental impact. So, the study was carried out to evaluate the influence of different tilapia strains (Chitralada, Commercial, Red and Universidade Federal de Lavras [UFLA]) on the deposition of bodily chemical components in the carcass. The bodily components analyzed were water, protein, fat and ash. For the determination of the bodily chemical deposition curves by age, the exponential, Brody, logistic, Gompertz and von Bertalanffy models were adjusted. The Commercial and UFLA strains deposited water at a faster speed (P<0.05) compared with the remaining strains. As for protein, the Red strain had a lower estimated maturity weight (49.37 g), and was more precocious (202 days) with regard to maximum deposition in comparison to the other strains (Chitralada, UFLA and Commercial) in which there was an estimated maturity weight of 231.5 g and maximum depositionfor 337 days. There were no differences (P>0.05) for the logistic model parameter between Red, UFLA and Commercial strains for fat, which presented a maximum fat deposition (0.23 g) at 310 days of age. Regarding ash deposition, the Commercial strain presented a higher maximum deposition (0.10 g) at 337 days, occurring later than the other strains that presented maximum deposition (0.033g) at 254 days of age. Thus, it was concluded that the genetic strains evaluated differ in chemical deposition curves of water, protein, fat and ash.

Diversidade Ictiofaunística e Ecologia reprodutiva de uma espécie nativa de peixe da Bacia Piranhas-Assu, RN

The Caatinga biome is rich in endemic fish species fauna. The present study the results of fish faunal surveys conducted in the hydrographic basin of Piranhas-Assu of the Brazilian Caatinga biome. The fish samples collected were distributed in four orders (Characiformes, Perciformes, Siluriformes and Synbranchiformes), 11 families (Characidae, Curimatidae, Auchenipteridae, Anostomidae, Prochilodontidae, Erythrinidae, Cichlidae, Sciaenidae, Heptapteridae, Loricariidae, Synbranchidae) and 22 species, of which 17 are endemic and five have been introduced from other basins. The order Characiformes was the most representative in number of species (46,35% ) followed by Perciformes (35,38%), Siluriformes (17,44%) and Synbranchiformes (0,5%). The Nile tilapia, Oreochomis niloticus, the only exotic species, was most expressive in number of individuals (24.92%) followed by the native species piau preto, Leporinus piau (18,77 %). Considering the relative frequency of occurrence of the 22 species, 13 were constant, five were accessory and four were occasional. This study investigated the reproductive ecology of an endemic fish black piau, Leporinus piau from the Marechal Dutra reservoir, Acari, Rio Grande do Norte. Samplings were done on a monthly basis from January to December 2009, and a total of 211 specimens were captured. The environmental parameters such as rainfall, temperature, pH, electrical conductivity and dissolved oxygen of water were recorded. The sampled population showed a slight predominance of males (55%), however females were larger and heavier. Both sexes of L. piau showed positive allometric growth, indicating a higher increase of weight than length. The first sexual maturation of males occurred at smaller size, with 16.5 cm in total length than females (20.5 cm). During the reproductive period, the condition factor and gonadosomatic index (GSI) of L. piau were negatively correlated. This species has large oocytes with a high mean fecundity of 54.966 with synchronous oocyte development and total spawning

Diversidade Ictiofaunística e Ecologia reprodutiva de uma espécie nativa de peixe da Bacia Piranhas-Assu, RN

The Caatinga biome is rich in endemic fish species fauna. The present study the results of fish faunal surveys conducted in the hydrographic basin of Piranhas-Assu of the Brazilian Caatinga biome. The fish samples collected were distributed in four orders (Characiformes, Perciformes, Siluriformes and Synbranchiformes), 11 families (Characidae, Curimatidae, Auchenipteridae, Anostomidae, Prochilodontidae, Erythrinidae, Cichlidae, Sciaenidae, Heptapteridae, Loricariidae, Synbranchidae) and 22 species, of which 17 are endemic and five have been introduced from other basins. The order Characiformes was the most representative in number of species (46,35% ) followed by Perciformes (35,38%), Siluriformes (17,44%) and Synbranchiformes (0,5%). The Nile tilapia, Oreochomis niloticus, the only exotic species, was most expressive in number of individuals (24.92%) followed by the native species piau preto, Leporinus piau (18,77 %). Considering the relative frequency of occurrence of the 22 species, 13 were constant, five were accessory and four were occasional. This study investigated the reproductive ecology of an endemic fish black piau, Leporinus piau from the Marechal Dutra reservoir, Acari, Rio Grande do Norte. Samplings were done on a monthly basis from January to December 2009, and a total of 211 specimens were captured. The environmental parameters such as rainfall, temperature, pH, electrical conductivity and dissolved oxygen of water were recorded. The sampled population showed a slight predominance of males (55%), however females were larger and heavier. Both sexes of L. piau showed positive allometric growth, indicating a higher increase of weight than length. The first sexual maturation of males occurred at smaller size, with 16.5 cm in total length than females (20.5 cm). During the reproductive period, the condition factor and gonadosomatic index (GSI) of L. piau were negatively correlated. This species has large oocytes with a high mean fecundity of 54.966 with synchronous oocyte development and total spawning