• Análise de parâmetros físico-químicos e biológicos no sistema intensivo de produção de tilápia do Nilo.

      Pires, T. B. (Universidade Estadual de Maringá . Centro de Ciências Agrárias . Programa de Pós-Graduação em Zootecnia, 2014)
      This work was performed at the Crow River, a tributary of Rosana reservoir (RP/SP) located in the area between the towns of North Diamond (PR) and Terra Rica. 18,000 juveniles post-reversed for male of Nile tilapia (O. niloticus), from the variety GIFT were used. From these animals the biomass data at intervals of approximately thirty days were collected in the summer period, to determine the feeding management. The evaluation of limnology, temperature, dissolved oxygen, oxygen saturation, electric conductivity and transparency were determined in situ. For these were used a sampling interval of about fifteen days and were evaluated at three levels of the water column; while the evaluation of the levels of total nitrogen, orthophosphate and nitrate occurred at intervals of thirty days and in two levels of the water column. Limnological data were collected at an interval of four hours between each repetition in the day. The collection of aquatic macroinvertebrates occurred through a method of natural colonization, called bio collector, made from a plastic net with a capacity of five kilos and using as substrate 15g of Cattail (Typha sp.), 10 cm of plant bush and about 450g of crushed stone and gravel, with six replicates for each point. One triplicate of bio collectorswas exposed for about 15 days and the other three for about 30 days from the date of its implementation. The data of the limnological variables were subjected to descriptive analysis and variance (Anova) and means were compared by the Scott-Knott test at 5% probability. A statistical analysis using the Poisson distribution with log link function to the data obtained by counting identifiedaquatic macroinvertebrates was applied. The number of individuals and the richness were used to evaluate: collection points established; transects formed with the deployment of cages; the effect of stocking densities of fish in cages and the exposure time of bio collectors. The system of cultivation in cages caused a significant variation (P<0.05) in oxygen content and pH. On average in the transect without cages the saturation by oxygen, and the oxygen dissolved in water is 2.9% and 0.24 mg/L to higher than the available transects in cages, with significant difference (P <0.05) between these transects. But even with the effect of fish farming indexes of water quality evaluated have not breached the levels imposed by Resolution No. 357/2005 of Conama, indicating that the environment has the capacity to assimilate mitigating the impact of fish farming organic load imposed by the activity in function of waste from feed and fish excreta. The sampling method of benthic macroinvertebrate communities was more efficient in the environmental monitoring than thelimnological variables, confirming that the increase of organic matter increases the density of these organisms, especially the group of Oligochaeta, Hirudinea and Gastropoda. These results demonstrate the importance of studies in this area to define more precisely the methodological procedure and studies aboutthe responses of groups of benthic macroinvertebratesin function of aquaculture production activities.
    • Avaliação da diversidade genética e do manejo reprodutivo em pacu, Piaractus mesopotamicus.

      Povh, J. A. (Universidade Estadual de Maringá. Centro de Ciências Agrárias. Programa de Pós-Graduação em Zootecnia, 2007)
      In many Brazilian Rivers it has been observed a decrease and even a disappearance of many fish species caused by factors as pollution, building dams and over fishing. Among these species, the pacu (Piaractus mesopotamicus) nowadays is barely found in some rivers, for example, in the Paranapanema River. As a fonn to outline the impacts on fish's populations, the restocking technique has been very used in Brazil. However, this practice has been realized, in general, without any scientific support. Facing this scenery, any action that seeks the environment recovery should look for the monitoring by scientific ways not basing in suppositions. Among methodologies for this aim, the molecular markers are tools that can be used to recognition and genetic characterization of stocks (native and broodstocks) and fish that will be get free in the environment. So, the works presented here evaluated the genetic diversity of Piaractus mesopotamicus collected in the middle of Paranapanema River, of fish farming broodstocks with restocking purpose, and also offspring's obtained by extrusion and semi-natural reproductive systems. For these evaluations the molecular markers RAPD (Random Amplified Polymorphic DNA) and microsatellite were using, both based on PCR (Polymerase Chain Reaction). The results showed a lower genetic variability of stock in relation to population, promoted by founder effect of this stock and/or due to different origin of fish that formed the stock. However, the moderate genetic differentiation and high Nm obtained indicate that populations and stock presented a similar genetic pool. As for the reproductive systems, a great genetic variability reduction was observed in the offspring from extrusion reproduction system in relation to the semi-natural system. Although this last system has presented dominance of some reproducers, due multiple patemities existence, there was a genetic Variability maintenance of offspring in relation to reproducers.
    • Avaliação da qualidade dos gametas de tambaqui (Colossoma macropomum) ao longo da estação reprodutiva.

      Galo, J. M. (Universidade Estadual de Maringá. Centro de Ciências Agrárias. Programa de Pós-Graduação em Zootecnia, 2013)
      The objective, in this work, was to analyze the reproductive behavior of the Colossoma macropomum specie, on quality of its male and female gametes throughout along the reproductive station, in order to determine the best time to accomplish the reproduction. Besides, it was analyzed the interaction among the presence of proteins of the seminal plasma of the C. macropomum as an indicators of seminal quality post-thawing. The experiment was carried out in Pimenta Bueno-Rondônia, in the reproductive station of November of 2009 to January of 2010, and November of 2010 to March of 2011. 23 males of C. macropomum were used during the reproductive station of 2009-2010, and 36 females in the station of 2010-2011. The male gametes were collected for the quali-quantitativas analyses along the reproductive station, every 15±5 days, the same happened with the collection of the feminine gametes, being classified as: period (1) - beginning of November (11/09); (2) - final of November (11/25); (3) - middle of December (12/14); (4) - beginning of January (01/03), and (5) - final of January (01/22); (6) - beginning of February (02/07); (7) - final of February (02/23); (8) - beginning of March (03/10) and (9) - final of March (03/28). During the evaluations of the spermatic quality in the periods three (middle of December) and four (beginning of January) from 2009/2010, an aliquot of semen of each animal was cry preserved, using Beltsville Thawing Solution (BTS) with 8% DMSO. A sample of 200 μL of semen of each animal, was diluted in 800 μL of BTS, and centrifuged in 800 rpm, and only the supernatant (proteins) was cry preserved to subsequent analysis of the protein outline of the seminal plasma, through the one-dimensional electrophoresis (SDS-PAGE). After 15 days the cryopreservation, a "pallet" with cry preserved semen was thawed for analysis of the quali-quantitative parameters. For the sperm parameters, it was not verified (P>0.05) period effect inside station for semen volume, spermatic vigor, time motility and spermatic concentration. When the progressive motility was evaluated among the collection periods, the effect (P <0.05) found was of quadratic behavior. About the sperm morphology significant differences were verified (P <0.05) in the probability of occurrences of normal sperms, primary and secondary abnormalities in function of the collection period. The fertilization rate and hatching presented significant effect (P <0.05) inside the period. For the qualitative parameters of the female gametes during the season 2010-2011, it was verified (P <0.05) period effect (it collects) inside the season for amount of oocytes, productive index and fertilization rate (P <0.05). In spite of the period 3 (collection - month of December) had not differentiated (P>0.05) from some periods, it was the period that presented the best established parameters for the oocytes'quality . For the analysis of the seminal plasma, considering all the collections, SDS-PAGE identified 15 protein bands (12, 25, 29, 34, 37, 40, 44, 50, 65, 70, 75, 78, 85, 90 and 100 kDa). When the interaction was evaluated (presence or absence) of the proteins found in the seminal plasma, with the sperm parameters post-thawing, great influence of the presence of the proteins was observed for sperm quality. Most of the proteins found in the seminal plasma influenced (P <0.05) the progressive motility of the frozen semen with DMSO. In consequence, a larger fertilization rate was observed (P <0.05) with the presence of the proteins 12, 34, 44, 85 and 90 kDa. In conclusion, the qualitative parameters of the semen and oócitos of C. macropomum presented changes during the reproductive station. The changes in the qualitative parameters of the semen can be associated to the aging processes of the sperms in the end of the reproductive station that can take a consequent reduction of the fertilization rates and hatching. The weight of liberated oocytes, production index and fertilization rate, had better results observed in the periods of December and January, indicating a better time to place the species reproduction. The proteins of the seminal plasma of C. macropomum influence the sperm quality post-thawing, as well as they can be used as indicators for the sperm quality post-thawing, mainly the proteins with molecular weight 50 kDa.
    • Avaliação de Homeopatila RS, em tilápias do Nilo, Oreochromis niloticus (Linnaeus, 1758), fase de larvicultura, no desenvolvimento, proporção sexual e histologia de brânquias e fígado.

      Zabott, M. V. (Universidade Estadual de Maringá. Centro de Ciências Agrárias. Programa de Pós-Graduação em Zootecnia, 2006)
      The Nile tilapias, Oreochromis niloticus, natives from Africa, are fishes worldly cultivated and they are characterized by great rusticity and adaptability to the most several cultivation systems. Considering the reproductive aspect they are precocious and males are larger than females. Exclusive populations of males are desired in this species due to the fact of having better performance and uniformity. In Brazil, the majority of the market demands for male fingerlings and they are obtained by sexual reversion using steroids hormones. The objective of this paper was to evaluate the effects of the homeopathic nucleus Homeopatila RS. This compound has as base the iodine, male gonads and Pituitary gland extract dinamization, so, an experiment were accomplished, with Nile tilapias during the period of gonadal differentiation for: a) evaluate the development and sexual proportion; b) investigate gills and liver fingerlings histological alterations. There were three distinct treatments: a) control, alcohol 30ºGL (C); b) hormonal, 17 a-metiltestosterone (H); c) homeopathic, Homeopatila RS, in hidroalcoholic solution (HH). The experiment was realized at the aquaculture center of Universidade Paranaense-UNIPAR, Umuarama-PR, from February to April 2006, for 45 days. It was used 4.800 post-larvae, distributed in 12 water boxes (500L). Each treatment had 4 replications totalizing twelve units. The results showed that there is not an effect (p>0.05) correlation between sexual proportion and use of Homeopatila RS, when observing the male and female gonads frequencies in relation to the control group. The hormonal treatment, showed a higher significantly frequency male gonads and intersex in relation to the other treatments, being absent the females frequency in this treatment. The animals? performance data analysis revealed significant differences 13 among the treatments (p < 0.05). The homeopathy treated group had a higher survival rate and a lower liver-somatic index, when compared with other groups. The histological analysis showed a significant difference (p<0.05), for the medium values of hepatic alterations, to lipidic inclusion, being lower than other treatments. There were not differences (p>0.05), for gills histological alterations. As conclusion, the homeopathic nucleus Homeopatila RS, added in Nile tilapias ration, during the gonadal phase differentiation, did not induce a sexual proportion alteration, in terms of masculinization, but showed a positive effect in the survival. The animals treated with homeopathy had smaller hepatic lipidic inclusion compared with other treated groups
    • Avaliação do citrato de tamoxifeno e temperatura na inversão sexual da tilápia do Nilo (Oreochromis niloticus).

      Zanoni, M. A. (Universidade Estadual de Maringá. Centro de Ciências Agrárias. Programa de Pós-Graduação em Zootecnia, 2011)
      Aquaculture in Brazil has been improving and finding new techniques to improve the quality of fish produced, one of the main problems is the use of steroids in sex inversion of tilapia, despite being a widespread technique and practiced in various regions of the world is increasing concern to environmental liabilities generated by the use of 17 α-methyltestosterone. In this context, this study aims to evaluate the overall use of non steroids in sex inversion of Nile tilapia. The first experiment was conducted to evaluate the influence of citrate tamoxifen on sex inversion of Nile tilapia larvae from two days of life, they were divided into an experimental design of five treatments and three replicates, and fed diets with different amounts of citrate tamoxifen: 0, 25, 50, 75 and 100 mg kg-1 of feed. After 28 days of treatment, the larvae remaining in each treatment were counted and transferred to water tanks of 500 liters which were fed a diet containing 28% crude protein for 60 days. After this period the fry were sexed by the "squash" method. The survival 75.5 ± 5.74, 73 ± 4.76, 66 ± 11.19, 76.5 ± 4.12, 75 ± 3.46 and average percentage of male individuals 62.5 ± 5, 70 ± 8.1, 60 ± 8.2, 70 ± 0.0, 62.5 ± 9.5 for treatments 0, 25, 50, 75 and 100 mg of citrate tamoxifen kg-1 diet, respectively, showed no statistically significant differences. The number of gonads in each subject experienced a significant reduction in the treatments with 75 and 100 mg of citrate tamoxifen (89.3 and 79.3 ± 0.527 ± 0.378) when compared with treatments 0, 25 and 50 mg of citrate tamoxifen (98, 9 ± 1.0, 97.6 ± 1.0 and 94.5 ± 1.0, respectively), the histological structure of female gonads did not differ and ovaries in all treatments showed well-defined and oocytes at various stages of maturation. The second experiment evaluated the effects of temperature 28, 30, 32 and 34°C and control (28ºC + ration plus 60 mg of 17 α-methyltestosterone) in sexual inversion, survival and presence of deformities in Nile tilapia. The results showed a statistical difference between the proportion of males, with a temperature of 32 and 34°C and control (91 ± 0.71; 96 ± 0.59 and 98.33 ± 1.0%, respectively) showed better results than those obtained for 28 and 30 degrees treatments (71 and 82 ± 0.29 ± 0.33%). Survival: 90.49 ± 2.32, 88.20 ± 2.04, 85.43 ± 1.58, 82.16 ± 1.63 and 90.74 ± 2.28% for temperatures 28, 30, 32 and 34°C, respectively, showed no statistical differences, but there were differences in survival between the control and treatments 32 and 34°C. In the analysis of radiographs was not possible to observe the presence of morphological changes in fish subjected to different treatments. With this experiment it was concluded that temperatures of 32 and 34°C larvae were able to genetically masculinizing females, and that there was no increase in mortality and in deformities presence that can be attributed to treatment. This technique is an alternative to the use of steroid hormones. The third experiment was conducted in order to describe gonads of Nile tilapia fingerlings (Supreme) with 75 days of age, using as a tool cytological techniques, structural and ultrastructural. Cytological technique gonads were stained with carmine acetate pressed between slide and coverslip and observed under light microscopy. To structural prepare gonads, after processing, were cut in microtome at thickness of 5 mm, stained with hematoxylin-eosin and observed under light microscopy. At the ultrastructural method, gonads were photo documented in a scanning electron microscope FEI QUANTA 200. The structural and cytological preparations allowed the visualization of the ovaries of oocytes, cell boundaries, nuclei and nucleoli associated. In males the cytologic preparations did not allow a clear identification of the structures, but in preparing structural testicular sperm was possible to visualize cysts, Sertoli cells and the beginning of the formation of seminiferous tubules. The scanning electron microscopy, used to visualize surface allowed, after the fracture of the gonads, to observe internal structure, such as spermatogonia, oocytes and collagen fibers. The results showed that all three techniques were efficient in distinguishing the sex of the individual, allowing observation and comparison of the structures present in the gonads.
    • Avaliação dos parâmetros seminais de pacu (Piaractus mesopotamicus) e sua correlação com as taxas de fertilização, eclosão e morfologia das larvas.

      Galo, J. M. (Universidade Estadual de Maringá. Centro de Ciências Agrárias. Programa de Pós-Graduação em Zootecnia, 2009)
      The objective in this work was to identify through the parameters of quality of the pacu semen (Piaractus mesopotamicus), of the fertilization rate, hatching and morphology of the larvae, indexes that allow certifying the animal with the best reproductive characteristic.Besides, to find possible correlations among the parameters qualiquantitative of the semen with the fertilization rate, hatching rate, and with the larval morphology, coming of eggs fertilized with semen "in natura" and frozen. A total of 42 males and 16 females of P. mesopotamicus were used to evaluate the correlations among the seminal parameters with it rates of fertilization, hatching and morphology of the larvae. Through the extrusion the semen and the egg were collected, and appraised the seminal quali-quantitative parameters, and accomplished the fertilization of the eggs. According to the value of the percentage of the fertilization rate of each crossing (maleXfemale), the females were classified as: "good females" - with fertilization taxes ? 70% and "bad females" - with fertilization taxes <70%. The quali-quantitative parameters of the semen didn't present statistical difference (P>0.05) in relation to the groups of "good and bad" females. Only the percentage of bent tail was larger (P <0.05) in the semen that fertilized the egg of the group of "good females", and broken tail was larger (P <0.05) in the semen that fertilized the group of the "bad females". The fertilization rate, hatching and percentage of normal larvae were larger (P <0.01) in the group of the "good females". Already the percentage of wasted eggs, larvae no emerged alive and no emerged died, it was larger (P <0.05) in the group of "bad females". Defective and dead larvae didn't differ (P>0.05) among the two groups. The main correlations found in the group of the "good females" were: progressive motility with primary abnormalities (r=-0.23; P=0.07). Spermatic concentration with hatching rate (r=0.25; P=0.05) and with wasted eggs (r=-0.34; P=0.007). The correlations found in the group of the "bad females" were: motility duration with coiled tail (r=-0.35; P=0.04) and spermatic concentration (r=-0.67; P <0.0001); wasted eggs and spermatic xvi concentration (r=0.33; P=0.05). Already for the study of the quality seminal evaluation "in natura" and frozen and its correlation with the fertilization rate, hatching and morphology of the larvae, six males and six females of P. mesopotamicus were used induced with extract of carp pituitary. After the evaluation of the seminal parameters, a bracket of each collected sample was cryopreserved and later thawed. In the semen "in natura", motility, spermatic vigor, duration of the motility, normal spermatozoa and secondary abnormalities were larger (P <0.0001). The averages of the fertilization rate and hatching, percentage of normal larvae and defective larvae of the eggs fertilized with the semen "in natura", were larger (P <0.0001) in relation to the thawed semen. Correlation was just verified among quali-quantitative parameters of the semen "in natura" and thawed for: duration of the motility with spermatozoa of degenerate tail (r = -0.77; P=0.0002) in the semen "in natura" and (r = -0.54; P=0.01) thawed. Correlations of the quali-quantitative parameters of the semen "in natura" were not observed and thawed with the fertilization rate, hatching rate, wasted eggs and defective larvae. As for the run across results, it is ended that the found correlations can auxiliary in the previous evaluation of the semen and of the males, because you encourage with smaller indexes of spermatics abnormalities possess a progressive motility and its higher duration, possibly causing a larger fertilization rate. Beyond of that fact, if the quality of the egg is not good, so that it causes a better fertilization rate, the quality of the semen needs to present good indicators of the parameters. The quality seminal raised the primordial being except using egg of good quality. The quality spermatic was influenced by the freezing process, including the spermatic morphology in the semen of P. mesopotamicus, taking the alteration in the fertilization rate and hatching.
    • Avaliação genética e de efeitos ambientais em características reprodutivas de tilápia do Nilo.

      Yoshida, G. M. (Universidade Estadual de Maringá. Centro de Ciências Agrárias. Programa de Pós-Graduação em Zootecnia, 2014)
      The aim of this work was to investigate the effect of three different age classes and different reproductive environments in Nile tilapia female performance, as well as, to estimate the genetic parameters for reproductive traits using the Bayesian inference methodology. The data set contained information from 451 female Nile tilapia evaluated in two different environments in Maringá, Paraná State and in an environment in Alfenas, Minas Gerais State. The spawning observation was carried once a week from October 2012 to March 2013, corresponding to 23 weeks of evaluation. For statistical analysis it was used the procedure Proc Genmod for the SAS statistical program and for the estimation of genetic parameters the computer program MTGSAM Threshold. The traits studied were spawning success, number of spawning, spawning frequency and volume of eggs/female. In statistical analyzes, Local 2 was inferior to the other Locals for the most of traits when using female of age 2. Statistical differences were not observed between Age 1 and 2 for the same Local of evaluation. The Age 3 present at Local 3 showed superior results when compared with female of age 2 for all traits. The heritability estimates were 0.14, 0.16, 0.53 and 0.02 for spawning success, multiple spawning, spawning frequencies and volume of eggs respectively and repeatability obtained for egg volume was 0.28. The results indicate that older females have higher reproductive performance than female of age 1 and 2 and should avoid the use of animals in individual hapas. Heritability estimates show genetic gain if used reproductive traits as selection criteria.
    • Contribuição genética e reprodutiva de piracanjuba (Brycon orbignyanus) submetidos aos sistemas de reprodução seminatural e extrusão.

      Castro, P. L. (Universidade Estadual de Maringá . Centro de Ciências Agrárias. Programa de Pós-Graduação em Zootecnia, 2015)
      Building hydroelectric dams in the course of Brazilian rivers is constantly associated with the large reduction in native fish populations. This action in addition to changing the entire water dynamics, is also a physical barrier that hinders the reproduction of migratory fish, such as piracanjuba (Brycon orbignyanus), strongly impacted species which is currently on the list of fish that are in danger of extinction. To mitigate the damages, a series of public policies were implemented, requiring biological compensation for the use of inland waters for electricity production and restocking, restoring natural populations from the release of alevins, is the most commonly adopted practice. However, if not carefully performed, this practice represents genetic and reproductive risk to populations still present in rivers, given the common loss of genetic variability in the production of alevins in the fish farms. The purpose of this study was to evaluate the influence of extrusion or semi-natural reproductive systems in different breeding (a female to three males and two females to six males), on the genetic and reproductive variability of the obtained progeny. 360 larvae samples were taken (90 larvae for each treatment) as well as a fin fragment from the 24 breeders used, and the genetic variability analyzes performed by PCR (Polymerase Chain Reaction) with amplification of eight microsatellite heterologous primers. 30 alleles were identified ranging from three to four per locus, so that 75% of higher frequency in the parental alleles were also in the offspring, demonstrating the maintenance of allelic frequencies in all treatments. The rates of expected heterozygosity and Shannon found the maintenance of genetic variability, observing the increase of its values in all progenies in relation to their parents. On the other hand, the parental contribution analyzes showed better results for treatments of the reproductive system by extrusion, since apparent relations of reproductive dominance were observed among the males in the semi-natural system, thus the increased number of breeders in the system was responsible for the intensification of this behavior. Moreover, better fertilization, hatching and mortality rates of breeders were observed in the semi-natural system, result associated to injuries caused by abdominal massage in extrusion. Thus, a reduction in the male x female ratio is indicated in the production of piracanjuba alevins in semi-natural system in fish farms aimed at restocking, while in extrusion systems increasing this ratio favors a more homogeneous parental contribution, but it is conditioned to effective participation of all males which can be guaranteed by semen quality analysis.
    • Crioconservação de embriões de tambaqui (Colossoma macropomum).

      Fornari, D. C. (Universidade Estadual de Maringá. Centro de Ciências Agrárias. Programa de Pós-Graduação em Zootecnia, 2012)
      Cryopreservation of genetic material of fish has become a tool essential for preservation of biological materials and production. However, stocking of fish embryos in liquid nitrogen (-196°C) and maintain indefinitely is not yet possible. Recently, developments in research on cryopreservation allowed storing embryos at -8°C for 24 hours. This indicates the possibilityof fish embryo cryopreserving, moreover, the biotechnical cooling for a short time already has practical applications. The present study aimed to evaluate the efficiency of different cryoprotectants to the processes of cryopreservation (freezing, vitrification and cooling) of tambaqui embryos (Colossoma macropomum). Despite not having succeeded in tambaqui embryos cryopreservation important points has been clarified as related to damage to the embryos. Injuries and morphological changes in embryos were identified at all stages of the freezing process, being higher with stabilization at -35°C after being submerged in liquid nitrogen and thawed. At the moment of the seeding besides a lower incidence of injuries, higher percentage of embryos with chorion were observed. The freezing curve protocolstested have not prevented the formation of ice crystals, thus turning unfeasible the embryonic embryos C. macropomum freezing. In the experiment of vitrification the methanol 20% with two-minutes of pre-immersion in exposure to liquid nitrogen, preserved the chorion and some cellular structures. Although it avoided further damage was not sufficient to prevent mortality of embryos, these results open perspectives for continued studies on cryopreservation of fish embryos. Ethylene glycol, glycerol and DMSO were toxic at higher concentrations (20 and30%) not being interesting for the vitrification of embryos C. macropomum. In tests of cooling to at -8°C treatments with ethylene glycol, glycerol and DMSO associated withsucrose did not result in satisfactory answers. To store embryos of C. macropomum at -8°Cfor a period of six hours is suggested cryoprotectant solutions with 17% sucrose combinedwith 10% methanol.
    • Desempenho de três linhagens de Tilápia do Nilo (Oreochromis niloticus) em diferentes fases, densidades e níveis de proteína.

      Fulber, V. M. (Universidade Estadual de Maringá. Centro de Ciências Agrárias. Programa de Pós-Graduação em Zootecnia, 2007)
      The present work objective to evaluate the productive performance of three Nile Tilapia (O. niloticus) lines during the initial and growing phase in different stocking densities also during the final phase with different crude protein levels (25 and 30%). The evaluated lines were: Bouaké, Chitralada and GIFT (Geneticaly Improved Farmed Tilapia). The experiment was carried out in three phases from February to November of 2006. in the first two phases it was used a kind of greenhouse installation, with a total of 500L water box were it was tested three Nile Tilapia lines and three stocking densities (15, 20 and 25 fish per box). In the initial phase, with a lasting of 28 days from February to March of 2006 and (06, 10 and 14 fish per box) during the growing phase with 53 days of lasting from March to April of 2006. Each phase characterized by nine treatments with three replications. The final phase had 204 days and was from April to November of 2006. For so, the fish were individually marked with an electronic Passive Integrated Transponder (PIT) tags implanted in the abdomen, guarantying the secure and permanent identification of fish using a code formed by letters and numbers that allowed the lecture by using an electronic lecture scanner. The final phase last 204 days and was carried out from April to November of 2006. There were used three fish lines totalizing 230 fish that were proportionally divided and allocated in two land tanks of 140m2 each one. Each tank received commercial rations with different crude protein (CP) levels being 25% of CP for one tank and other one with 30% of CP. The water quality parameters kept adequate for the different densities during the first two phases not affecting lines performance. In the initial phase comparing the densities inside the same line, Chitralada and GIFT did not show difference. However, Bouaké line showed sensibility to the stocking density increase with total final length average, final weight and gain weight significantly lower to the higher evaluated density while the surviving rate kept normal levels to this specie phase. The growing phase results to the average final performance showed differences (P< 0.05) among evaluated densities inside the same lines, being the lower density the most efficient. But comparing the same density among the different lines it was not observed significant differences. The different densities showed a straight relation between the increased density and performance reduction. In the final phase the average temperature during the winter contributed to the feed ingestion restriction by fish during the coldest days what could have influenced the lines performance. However, when evaluating the water quality parameters it was observed that the averages for these factors kept satisfactory to the adequate specie growing. The average performance of fish fed with ratio containing 25% of CP were higher in 46.0%, 35.0% and 51.0% for Bouaké, Chitralada and GIFT, respectively, when compared to the fish of the same line that received ration with 30% of CP, showing an inverse relation between CP levels increase and productivity, suggesting a lower CP levels necessity to Nile tilapias diet during the final phase, decreasing the ambient impact with lower nitrogen amounts being lost and also decreasing the cost production since protein is the most expensive ingredient of rations and does not necessary affect the biological value. Comparing the three tilapia lines performance, the GIFT showed to be the most efficient for all evaluates parameters independent of the crude protein level supplied, followed by Chitralada and Bouaké. The most efficient average of GIFT in relation to the others lines reported its potential genetic improvement in relation to the no improved lines.
    • Desempenho produtivo e econômico da Tilápia do nilo (O. niloticus) cultivada em tanques-rede nos períodos de inverno e verão, no rio do Corvo-Paraná

      Filho, L. A. (Universidade Estadual de Maringá. Centro de Ciências Agrárias. Programa de Pós-Graduação em Zootecnia, 2008)
      This project aimed to evaluate the performance and economic viability of fish creation in net cages as an alternative to improve life quality of the producers from Corvo River (Parana, Brazil) with minimum environmental impact and great sustainability. The research involved water quality monitoring considering the physic-chemical parameters and evaluation of zootechnical and economical indexes to three storage density in net cages with 100, 150 and 200 fish m-3 in summer and winter cultivation. The species used was Oreochromis niloticus of Thailandese strain, submitted to the sex reversal process. There were used 14,850 juvenile fish in the summer and 8,910 in the winter with 57 and 99 g of weight respectively, and distributed in 6.0 m³ useful cages, being 15 in summer and 09 in winter. The trial period of the summer was 84 days and 140 in winter; however, to final biomass calculation in the summer the weights from 130 days were used. The diet was composed by extruded commercial food, one with 32% PB for the first 30 days and another with 28% PB until the slaughter. The collects of limnological variables were done each thirty days in sub-surface layers, in a longitudinal transect inside the cage. Data of electrical conductivity and pH (digital potentiometers), water temperature daily monitored with maximum and minimum thermometer, dissolved oxygen, and transparency were obtained. The data from the limnological evaluation were submitted to an exploratory analysis through the descriptive statistics, and for the zootechnical and economic evaluation the variance analysis by GLM process were applied, followed by multiple comparison of average using the Tukey test (p<0.05). The physical chemical indicators for both periods were adequate to the limits of the studied specie, except in winter when the average temperature of 20.99°C influenced the results. The production cost structure used in the study was followed by the methodology of Production Operational Cost and as profitability indicators the Gross Revenue and Operating Profit. Analyzing the final zoothecnical performance of two seasons, it was observed that there was no difference (p<0.05) among the three densities in the two periods for final and daily average weight when analyzed separately. Survival rates during the summer showed differences (p<0.05) among treatments, and the lowest rate was for treatment with the highest density (79.99%), while treatments with lower density had the highest rate survivors (94.57%). Comparing the summer and winter period, it was found that there is a difference (p<0.05) for the obtained average weights in the same space-time cultivation. Fish reared in the summer showed a better performance than in the winter (460.40 grams and 367.76 grams respectively) with daily average weight gain of 5.60 g day-1 during the summer, and 3.58 g day-1 in winter. Differences were found (p<0.05) when it was examined the final biomass and feed intake, and the increases were rising as density was increased. The increase in consumption in summer has a direct influence on reducing the apparent food conversion, so that there was difference (p<0.05) for the three densities between the two periods. When it was analyzed the economic indicators in both periods, there was a difference (p<0.05) for all studied variables. The total operational cost (per kg of fish) in the summer period was R$ 2.19 and R$ 1.55 in the winter and the Operating Profit per kg of fish produced was higher in winter (R$ 0.95) than in the summer (R$ 0.31). It was concluded that increased density did not influenced the performance of the fish, therefore, it can establish that a density of 150 fish m-3 for the summer period and 200 fish m-3 for the winter can be used and that the production of the tilapia Nile in cage is economically viable for both periods.
    • Desenvolvimento de misturas liofilizadas para croquete de tilápia do Nilo.

      Fuchs, R. H. B. (Universidade Estadual de Maringá. Centro de Ciências Agrárias. Programa de Pós-Graduação em Zootecnia, 2013)
      The Nile tilapia (Oreochromis niloticus) is a fish whose production is growing worldwide. It has mild flavor, low fat and high acceptability, being consumed mainly in the form of fillets. However, this cut represents only 30-35% of the live weight of the fish. The meat which is adhered to fish carcass after filleting process may be removed and used in the development of new food products. This meat is called mechanically separated meat (MSM) or tilapia mince. The objective of this study was to use the MSM of Nile tilapia in developing freeze-dried mixtures of fish croquette, enrich it with flaxseed flour to increase your omega-3 content and evaluate the chemical, microbiological and sensory stability for 240 days. Cost, fiber content and sensory analysis of flavor, texture and overall acceptance of seven formulations of tilapia croquette were evaluated, varying levels of wheat, oats and rye used in its production. A genetic algorithm (GA) with desirability functions was combined with a multiobjective optimization of the response surface models. The optimized mixture, called basic formulation was freeze-dried until a constant value for water activity (aw) was obtained. Through a preference ranking test (p <0.05), it was determined the higher content of flaxseed flour can be added to the basic formulation, with no changes to the basic formulations and the enriched one. The two formulations, raw and deep fried in soybean oil had their proximal composition and fatty acid composition determined. Indices of nutritional quality of lipids from the basic and enriched formulations (raw and deep fried) were also evaluated. The parameters evaluated were index of atherogenicity (AI), index of thrombogenicity (IT) and ratio HH (hypocholesterolemic fatty acids/ hypercholesterolemic fatty acids). The freeze-dried samples of mixtures of tilapia croquete were vacuum packed in transparent plastic bags with a thickness of 180? and stored in dark plastic boxes at room temperature (24oC ± 3oC). The stability of both formulations were evaluated through analysis of TBARS and aw (on days 0, 30, 60, 90, 120, 150, 180, 210 and 240), total and fecal coliforms, Staphylococcus coagulase positive, molds and yeasts, Bacillus cereus and Salmonella sp (on days 0, 120 and 240) and sensory acceptance of the attributes appearance, texture, odor, flavor and overall acceptance (on days 0, 210 and 240), using 9-point hedonic scale. The combination of flours was chosen to minimize the cost and maximize the overall acceptance and fiber content. The overall acceptance showed a statistically significant correlation (p?0.05) with flavor (r=0.67) and texture (r=0.61). The GA-based approach indicated that the highest overall acceptability is obtained when using wheat and rye flours in equal parts. This formulation had an overall acceptance of 7.52, fiber content of 11.50 g kg-1 and cost of $ 2.21/ kg. After 24 hours of freeze-drying the water activity of the mixture was 0.11. The ranking preference test indicated that the limit of addition of flaxseed flour is 12.5 g 100 g-1. In addition to the enhanced content of omega-3, the enriched formulation showed a lower loss of this substance during frying and better indices of nutritional quality of lipid than the basic product. The water activity of mixtures increased significantly (p <0.05) ranging between 0.1666 and 0.5392 (control mixture) and between 0.0554 and 0.5415 (enriched misture). TBARS values were increased significantly (p<0.05), from 0.08 to 0.38 mg MDA kg-1 (control mixture) and 0.11 to 0.40 mg MDA kg-1 (enriched mixture). The attributes appearance, texture and overall acceptance of the control mixture remained constant and flavor was improved during storage. During the evaluation period, the enriched mixture did not change the acceptance of its sensory attributes (p<0.05). After 120 days of storage, the control mixture showed significantly higher overall acceptance than the averages of the enriched mixture. At the end of the evaluation, the overall acceptance was approximately 8 for control mixture and 6 for the enriched mixture. Microbiological parameters did not exceed the limits allowed for consumption. The use of genetic algorithm was a suitable tool in the optimization process of the basic formulation of tilapia croquette and freeze-drying contributed to the development of a product with high added value, high quality and stability. The enrichment of the basic formulation with flaxseed flour increased its nutritional value, with a high content of omega-3 fatty acids and improved IA, IT and HH ratio, even when this product is subjected to deep fat frying. Control and enriched freeze-dried mixtures of tilapia croquette remained suitable for consumption during 240 days of storage.
    • Diversidade genética de Brycon orbignyanus em sistema reprodutivo seminatural.

      Barrero, N. M. L. (Universidade Estadual de Maringá. Centro de Ciências Agrárias. Programa de Pós-Graduação em Zootecnia, 2007)
      Several ecological and climatic factors and especially those related to man's actions have led to the disappearance of piracanjuba (Brycon orbignyanus) natural populations. For the importance of the ecosystems in which it is located and by its qualities of fast growth and good adaptation to controlled environments, in the last years the producer's interest in the use of such migratory species has increased, aiming the production and the participation in conservation and stock enhancement programs. In the implementation of management and stock enhancement programs as conservation strategies, the genetic monitoring, the evaluation of reproductive procedures and the scientific support of different areas are necessary to obtain a correct maintenance and a greater objectivity of such programs. The purpose of this study was to evaluate the influence of the reproductive and semi-natural systems in the genetic diversity and the parental contribution of B. orbignyanus offspring's destined to stock enhancement programs of the Paranapanema River with the RAPD (Random Amplified Polymorphic DNA) and microsatellites molecular markers. The results showed an increase of the genetic variability when an equal proportion of sex was used, possibly due to the effective broodstock number used in the mating and the semi-natural reproductive system. The semi-natural system allowed the preservation of the reproducers in the reproductive process. The occurrence of multiple paternities and the reproductive dominance was verified. These results provide information's that will contribute to the development of management models in B. orbignyanus, ensuring a correct genetic and a reproductive monitoring that are important for a safe conservation of the specie.
    • Diversidade genética de Salminus brasiliensis utilizados em programas de repovoamento.

      Gomes, P. C. (Universidade Estadual de Maringá . Centro de Ciências Agrárias. Programa de Pós-Graduação em Zootecnia, 2015)
      In recent years there has been a decline in the capture of "dourado" fish (Salminus brasiliensis) in the Paranapanema River. The major factors causing this decline are: clearing of riverside vegetation, excessive fishing effort, capture of young individuals, drainage ponds, regulation of hydrological regime of rivers, construction of dams, pollution and introduction of exotic species. To preserve the genetic diversity of this species, it is necessary to develop programs that can mitigate the impact of dams on spawning. The production of juveniles is an alternative to conservation, aiming to populate fish ponds, large lakes, rivers and dams. But for an effective implementation of repopulation programs it is required genetic monitoring, evaluation of reproductive procedures and scientific support of different areas. The aim of this study was to determine whether there is transposition of individuals of S. brasiliensis on the transposition stairs of the hydroelectric plant of Canoas I and evaluate the genetic diversity of these individuals to renew the stocks of "dourado" at the Station of Hydrology and Aquaculture of Salto Grande and also assess the genetic diversity of breeders (5♂ and 5♀) from the progeny of this mating, which will be used in repopulation programs of the Paranapanema River through the molecular marker RAPD (Random Amplified Polymorphic DNA). The results showed that the transposition stairs of Canoas I allow the transposition of "dourado" (S. brasiliensis) at the middle Paranapanema River and that the three populations collected there can be used to renew the stock of "dourado" at Salto Grande (SP). It was also shown that there was a dominance of only one mating pair of Salminus brasiliensis in the semi-natural reproductive system. However, the genetic variability of the offspring produced by this system was maintained.
    • Diversidade genética de três estoques de piapara (Leporinus elongatus), utilizando RAPD.

      Gomes, P. C. (Universidade Estadual de Maringá. Centro de Ciências Agrárias. Programa de Pós-Graduação em Zootecnia, 2007)
      Recently the Brazilian aquiculture production has presented a great progress. Amongst cultivated native species in Brazil, piapara (Leporinus elogatus) has been widely praised. With the objective of to evaluate restock programs, the variability and genetic divergence of three piapara supplies had been analyzed, using RAPD technique. The first supply belongs to the Aquiculture and Hydrology Station of Duke Energy International (A); second to the Rolândia fish culture (B) and third to the Restock Program of Paraná Rivers (C). Ten primers used for RAPD produced 105 polymorphic loci, conferring a polymorphism of 98.1% for the three evaluated supplies. Polymorphism loci percentage and Shannon index were higher for a supply. However, all values were high, indicating high intrapopulation diversity. The Gst values indicate a low genetic variation between A x B stocking and a moderate differentiation amongst others. The Nm was higher between A x B supplies. Genetic distance and dendrogram, indicate that A x B supplies are less distant genetically.
    • Estimação de parâmetros genéticos de características de desempenho e de rendimento de filé de grupos genéticos de tilápias do Nilo.

      Kunita, N. M. (Universidade Estadual de Maringá. Centro de Ciências Agrárias. Programa de Pós-Graduação em Zootecnia, 2014)
      The objective of this study was to estimate (co ) variance, genetic parameters, common effect of family and genetic and phenotypic correlations for performance traits ( daily weight gain - GPD and total weight ) and yield (area, volume, body density and fillet yield ) of three genetic groups of tilapia : GIFT, ½ GIFT ½ Chitralada, 1/2 GIFT ½ Bouaké. The data set contained information from 859 animals being 563 males and 296 females. Breeding values of 968 animals in the relationship matrix were predicted. Single-trait analyzes of all traits and bicaracter associating trait fillet yield with daily weight gain, area, volume and density were performed. The analyzes were performed from the Animal Model using Bayesian inference by applying the MTGSAM program (Multiple Trait Gibbs Sampler using in Animal Model). The convergence of chains was tested by the method of Heidelberger and Welch. The heritability estimates for all traits, both in single-trait analyzes as bicaracter varied from 0.09 to 0.20 for fillet yield, indicating moderate magnitude. For the association between fillet yield with GPD, the value of the genetic correlation was -0.24 , with credibility intervals containing the zero value, showing the probability of no genetic association between these traits. Similar results were found for the genetic correlations between fillet yield and other traits, indicating the necessity of conducting a specific program of breeding for fillet yield.
    • Expressão gênica da proteína receptora da rianodina e qualidade da carne em tilápia-do-Nilo submetida ao estresse antes do abate

      Goes, E. S. R. (Universidade Estadual de Maringá. Centro de Ciências Agrárias. Programa de Pós-Graduação em Zootecnia, 2015)
      Fish management procedures in aquiculture, such as capture, handling and transport, are often traumatic and cause serious physiological and biochemical reactions. The importance of the reduction of pre-slaughter stress is due to the fact that vigorous swimming intensely employs the white muscle, increases the anaerobic glycolysis and the production of lactic acid, and decreases muscle´s pH with the structural degradation of muscular proteins. The above diminishes the meat´s water-holding capacity (WHC). The genetic factors bonded to changes in the muscle´s WHC are related to alterations in the activity of ryanodine receptors which may decrease the ability of this channel to control the release of calcium to the cytoplasm of the muscular cell, especially in periods of physical stress. Calcium excess in the cytosol causes fast muscular contraction, with an acceleration of anaerobic metabolism and post-mortem glycolysis. The muscle´s pH is drastically decreased, affecting the muscle´s capacity to retain water in the intracellular stores. Changes in muscle quality derived from pre-slaughter stress diminish shelf life and bring economic liabilities for the fish industry. Current analysis assesses the pre-slaughter stress caused by transport and its influence on stress indicators, fillets´ quality and sensorial factors, and genetic expression of the ryanodine receptor protein (RyR) in Nile tilapias.
    • Impacto da seleção genética na morfometria e desempenho de tilápias do nilo.

      Zardin, A. M. S. O. (Universidade Estadual de Maringá . Centro de Ciências Agrárias. Programa de Pós-Graduação em Zootecnia, 2015)
      This study aimed to estimate the variance and covariance components, genetic parameters and genetic associations of body traits and performance of Nile tilapia, Tilamax variety, grown in cages, and evaluate responses to selection and genetic evolution between generations, as well as verify the impact of selection on traits, when selecting fish based on daily weight gain. The data set used in the first study contained information of male and female tilapia grown in cages in 2011-12, 2013 and 2014. Estimates were made of variances and covariances components, genetic trends for height and tail width, trunk length, body area, harvest weight, daily weight gain and fillet volume by Bayesian Inference. An animal model considering random effects additive, residual and common family was used in additional to the fixed effects of sex and cages, in single-trait and bi-characteristics analysis. Genetic correlations between traits were positive and higher than 0.82, showing increase in traits, mainly body area and fillet volume. The heritabilities of body traits and performance were of moderate magnitude. Genetic gains were increasing to all traits, specially for daily weight gain, harvest weight, body area and fillet volume with values of 4.15, 4.59, 2.30 and 3.65% per generation, respectively. The selection based on daily weight gain resulted in indirect genetic gains in trait over the generations, changing body shape, increasing body weight with trends changing the fillet weight, as well as in the taking advantage of different cuts to the consumer market. The data set used in the second study contained information of male and female tilapia of Tilamax variety, produced in cages from 2008 to 2015. Estimates were made of variances components for total, standard and trunk length; height and width of the body, body area, harvest weight, daily weight gain and fillet volume by Bayesian inference, using single-trait analysis, in additional to genetic trends and rate of inbreeding. The heritabilities were of moderate magnitude with values between 0.14 to 0.28. The genetic trends showed increases of genetic values over the generations, with annual rates gains of 1.440 cm2 in body area, 12.90 g in harvest weight, 0.04 g day-1 in daily weight gain and 3.317 cm3 in fillet volume, representing 1.27, 2.35, 2.29 and 1.90% per generation, respectively. The rate of inbreeding showed small increment, with value of 0.36% for generation eight. The heritabilities values and genetic variances over the generations showed the genetic progress and response to selection, with the main gains in traits body area, harvest weight, daily weight gain and fillet volumes without reducing the genetic variability and with small increment of inbreeding, which enables genetic gains on future generations.
    • Influência da baixa temperatura e diferentes crioprotetores em oócitos e embriões de Colossoma macropomum e Piaractus brachypomus.

      Digmayer, M. (Universidade Estadual de Maringá. Centro de Ciências Agrárias. Programa de Pós-Graduação em Zootecnia, 2013)
      The aim of this work was to develop methods for cryopreservation of Colossoma macropomum oocytes and oocytes and embryos of Piaractus brachypomus, as well as to analyze the damages in oocytes and embryos after exposure to cryoprotectant solutions and cryopreservation. Oocytes of C. macropomum were distributed in six cryoprotectant solutions: T1 -methanol 1.6 M + sucrose 0.25 M, T2 - methanol 1.6 M + sucrose 0.5 M, T3 - methanol 1.6 M + trehalose 0.25 M, T4 - methanol 1.6 M + trehalose 0.5 M, T5 - methanol 1.6 M + fructose 0.25 M, T6 - methanol 1.6 M + fructose 0.5 M and T7 - outbreak control. Oocytes were kept in cryoprotectant solutions for 20 minutes at room temperature, fertilized and taken to incubators. A second portion of the oocytes were underwent to slow freezing, stored in liquid nitrogen, thawed, and a part was fixed while the other was fertilized and kept in incubators. The survival probability of oocytes subjected to T1 at room temperature was higher (15.8%). As for survival after hatched larvae, there was no difference between treatments. In the fertilization of oocytes that passed by slow freezing there was not hatching. Morphological preservation was observed in T1 and T2 with cryoprotectant solution containing methanol 1.6 M and sucrose 0.25 and 0.50 M, respectively. The oocytes of Piaractus brachypomus were distributed in eight cryoprotectant solutions: T1 - methanol 1.6 M + sucrose 0.25 M + 50 % L15, T2 -methanol 3.1 M + sucrose 0.25 M + 50 % L15, T3 - DMSO 0.7M + sucrose 0.25 M + 50% L15, T4 - DMSO 1.3 M + sucrose 0.25 M + 50% L15, T5 -methanol 1.6 M + sucrose 0.25 M + Hank, T6 - methanol 3.1 M + sucrose 0,25M + Hank, T7 -DMSO 0.7 M + sucrose 0.25 M + Hank, T8 - DMSO 1.3 M + sucrose 0.25 M + Hank. The embryos frozen at -13ºC were distributed in eight cryoprotectant solutions: T1 - methanol 3.1M + 0.15M PVP + Hank, xvi T2 - methanol 3.1 M + PVP 0.3 M + Hank, T3 - methanol 3.1 M + PVP 0,45M + Hank, T4 - methanol 3.1 M + PVP 0.6 M + Hank, T5 -methanol 3.1 M + sucrose 0.45 M + Hank, T6 - methanol 3.1 M + sucrose 0.63 M + Hank, T7 - methanol 3.1 M + sucrose 0.81 M + Hank, T8 - methanol 3.1 M + sucrose 1.0 M + Hank. Embryos frozen in liquid nitrogen were distributed in four cryoprotectant solutions: T1 - methanol 3.1 M + sucrose 0.45 M + Hank, T2 - methanol 3.1 M + sucrose 0.63 M + Hank, T3 - methanol 3.1 M + sucrose 0.81M + Hank, T4 - methanol 3.1 M + sucrose 1.0 M + Hank. For morphological analysis oocytes and embryos were processed in historesin and oocytes for scanning electron microscopy technique. For oocytes of P. brachypomus kept at room temperature and fertilized treatments that showed embryo development were T5 (methanol 1.5 M, sucrose 0.25 M solution and Hank), 17.3% and T7 (DMSO 0.7 M, sucrose 0.25 M and Hank) 1.8%. In fertilization of oocytes subjected to slow freezing curve there was not embryo development after fertilization. In the morphological analysis it was found that the oocytes of P. brachypomus when subjected to slow freezing in extender solution with methanol 1.6 M + sucrose 0.25 M + solution hank (T5) showed a full zona radiata with regular contour. From embryos that were underwent freezing at -13ºC in T5, 15.3% developed and was significantly higher than in T6 (4.6%), T3 (1.5%), T7 (1.8%) and T8 (1.9%) and there was also embryo development. In other treatments, all embryos subjected to cryoprotectant solutions at a temperature of -13ºC and embryos subjected to treatments in liquid nitrogen resulted in dead embryos. No treatment with oocysts of C. macropomum and oocytes and embryos of P. brachypomus provided maintenance of fertilizing capacity after freezing.
    • Interação genótipo X ambiente para peso vivo e modelagem estatística para seleção genética em tilápias do nilo (Oreochromis niloticus).

      Oliveira, S. N. (Universidade Estadual de Maringá. Centro de Ciências Agrárias. Programa de Pós-Graduação em Zootecnia, 2013)
      This study evaluated the existence of genotype x environment interaction for bodyweight in Nile tilapia (Oreochromis niloticus), GIFT range between three cities indifferent regions in the Paraná state. The data set consisted of 1,132 animals, males and females, born between November 2011 and February 2012. Analyses were performed using Bayesian inference, considering an animal model that included fixed effects of sex, linear and quadratic covariate of fish age (in days), in addition to the effects considered random, and the additive genetic and common environment hatchery (c) and nursery (w) , where the weight was treated as a different trait in each of the regions. The results of heritability were high for univariate models, being 0.71 , 0.72 and 0.67 for the cities of Palotina (PL) , Floriano (FL) and Diamante do Norte (DN) , respectively , the results of heritability for the two-trait analyzes showed similar values. Genetic correlations estimated in vicariate analyzes were weak with values between 0.12 PL-FL,0.06 for PL- DN and 0.23 for FL-DM. The Spearman correlation values were low, indicating change in ranking in the animals selection in different environments understudy. There was heterogeneity of phenotypic variance between the three regions and heterogeneity of residual variance between PL and DN. The direct genetic gain was greater for DN region with the value of 281.35 g of weight gain per generation, followed by FL with 198.24 g per generation and finally PL with 98.73 g per generation. The indirect genetic gains ranged from 7.77 g per generation between DNand PL to 74.66 g per generation between FL and DN. Eight statistical models were used to check what best describes the average daily weight gain (ADG), in order to make the best selection in animals subjected to genetic breeding program of tilapia(Oreochromis niloticus), variety GIFT, and the data set consisted of information from2,615 animals, from the fourth generation of selection (G4) . The analyzes considered the animal model that included fixed effects of sex, linear and quadratic covariate offish age, in days, in addition to additive genetic effects. The models were modified to include or not maternal genetic effect (m) and common hatchery environments (c) and nursery (w) . The results of heritability were considered the average for most models,M2 = 0.24, M4 = 0.23, M5 = 0.28, = 0.30 M6, M7 and M8 = 0.33 = 0.36 and high for models M1 = M3 = 0.83 and 0.79 . The Bayesian deviance information criterion (DIC)was lower for M1 (DIC = -282.59) and higher for M4 (DIC = 1754.57) . The criterion of log marginal density for Bayes factor agreed with the DIC to the lowest value at which M1 = 585.29 and the highest value presented for this criterion was for M5 =1837.37.