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Fumonisins are naturally occurring mycotoxins that contaminate food for human and animal consumption. They have neurotoxic effects, but the mechanisms by which these toxins affect the nervous system are not fully known. In the present study, male Wistar rats were fed between 21 and 63 days of age with diets that contained fumonisins B

The impact of oral supplementation with an effervescent glutamine formulation on the beneficial effects of antiretroviral therapies was evaluated in people living with HIV/AIDS. For this purpose, 12 HIV/AIDS carrier patients with CD4

Although fumonisins are identified as responsible for alterations in weight gain, little information is available on their effects on expression of growth-related genes, especially for Nile tilapia (Oreochromis niloticus) fingerlings. In this study, Nile tilapia fingerlings were treated with increasing levels of fumonisin B1 (FB1) and fumonisin B2 (FB2) (diets of 0, 20, 40, and 60 mg/kg) to evaluate their effects on weight gain (WG), feed intake (FI), feed efficiency (FE), growth hormone receptor (GHR) and insulin growth factor 1 (IGF-1) mRNA expression in liver of this fish. All variables were evaluated at 15 and 30 days of treatment. Diet containing 0 mg fumonisin/kg was used as control treatment. Treatment with 20, 40, and 60 mg fumonisin/kg of diet significantly reduced WG (P1 + FB2) affect the growth of Nile tilapia fingerlings through mechanisms that involve reduction of GHR and IGF-1 expression.

Made available in DSpace on 2019-10-06T16:25:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-05-30 Fumonisins (FB) are mycotoxins produced during secondary metabolism of Fusarium verticillioides and Fusarium proliferatum fungi and can prevent animal performance. In this study, the hypothesis that fumonisin affects the expression of IGF-1 and GHR genes in Nile tilapia (Oreochromis niloticus) fingerlings and juveniles was tested. Nile tilapia fingerlings and juveniles received diets with and without the inclusion of fumonisin (50 mg FB kg−1 of feed) to evaluate their effects on weight gain (WG), feed intake (FI), feed conversion (FC) and mRNA expression of GHR and IGF-1 in the liver. The fumonisin-free diet was used as a control treatment. All variables were evaluated after 20 days of treatment. The diet containing 50 mg FB kg−1 of feed significantly reduced WG (P < 0.0001) and worsened FC (P < 0.0001) for fingerlings, but did not affect FI. For juveniles, the inclusion of fumonisin did not affect FI, FC and WG. GHR and IGF-1 mRNA expression of both fingerlings and juveniles was significantly reduced by the inclusion of fumonisin (P < 0.0001). These results indicate that fumonisin affects the hepatic expression of GHR and IGF-1 in Nile tilapia, but the phenotypic effect is more evident in fingerlings. Program of Master in Science Technology and Food Safety Cesumar Institute of Science Technology and Innovation - ICETI. University Center of Mariná UNICESUMAR Department of Animal Breeding and Nutrition UNESP College of Veterinary Medicine and Animal Sciences São Paulo State University Department of Veterinary Science UNICESUMAR University Center of Maringá Department of Pharmacology and Therapeutics UEM State University of Maringá Department of Animal Science UFS Federal University of Sergipe Department of Animal Science UEM State University of Maringá Department of Animal Breeding and Nutrition UNESP College of Veterinary Medicine and Animal Sciences São Paulo State University

Made available in DSpace on 2018-12-11T16:51:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-03-10 In this study, we tested the hypothesis that the ingestion of feed containing fumonisin affects the apoptosis balance in liver cells. Thus, a trial was conducted with Nile tilapia fingerlings (2.64 ± 0.06 g) fed diets containing increasing levels of fumonisin (FB) (0-control diet, 20, 40, and 60 mg/kg), and expression of caspase7 (CASP7) and sphingosine phosphate lyase (SPL) genes in liver tissue was evaluated at 15 and 30 days of treatment. SPL:CASP7 mRNA ratio was also evaluated. Relative mRNA levels of SPL decreased in tilapia treated with 60 mg FB/kg of diet at 15 days (P

The impact of food restriction (FR) during 56 days on serum levels of cytokines in mice fed a high-fat diet (HFD) or high-carbohydrate diet (HCD) were evaluated. The amount of food was reduced 50% for HFD-FR and HCD-FR groups compared to mice receiving free access to HFD (HFD group) or HCD (HCD group). We quantified the serum levels of basic fibroblast growth factor, granulocyte-macrophage colony-stimulating factor, inducible protein 10, interferon γ, interleukin 1α (IL-1α), IL-1β, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12, IL-13, IL-17, keratinocyte chemoattractant, macrophage inflammatory protein-1α, monocyte chemotactic protein 1, monokine induced by IFN-γ, and tumor necrosis factor α. Only IL-12 levels were lower (P

During the early post-natal period, offspring are vulnerable to environmental insults, such as nutritional and hormonal changes, which increase risk to develop metabolic diseases later in life. Our aim was to understand whether maternal obesity during lactation programs offspring to metabolic syndrome and obese phenotype, in addition we aimed to assess the peripheral glucose metabolism and hypothalamic leptin/insulin signaling pathways. At delivery, female Wistar rats were randomly divided in two groups: Control group (CO), mothers fed a standard rodent chow (Nuvilab); and Diet-induced obesity group (DIO), mothers who had free access to a diet performed with 33% ground standard rodent chow, 33% sweetened condensed milk (Nestle), 7% sucrose and 27% water. Maternal treatment was performed throughout suckling period. All offspring received standard rodent chow from weaning until 91-day-old. DIO dams presented increased total body fat and insulin resistance. Consequently, the breast milk from obese dams had altered composition. At 91-day-old, DIO offspring had overweight, hyperphagia and higher adiposity. Furthermore, DIO animals had hyperinsulinemia and insulin resistance, they also showed pancreatic islet hypertrophy and increased pancreatic β-cell proliferation. Finally, DIO offspring showed low ObRb, JAK2, STAT-3, IRβ, PI3K and Akt levels, suggesting leptin and insulin hypothalamic resistance, associated with increased of hypothalamic NPY level and decreased of POMC. Maternal obesity during lactation malprograms rat offspring to develop obesity that is associated with impairment of melanocortin system. Indeed, rat offspring displayed glucose dyshomeostasis and both peripheral and central insulin resistance.

The effect of graded levels of dietary available phosphorus (AP) on large Nile tilapia (145.87 ± 9.51 g) performance, feed efficiency, body composition and mineral retention in vertebrae was evaluated. All male fish were distributed into three replicates in fiberglass aquaria (800 L each; 12 fish per tank) for 87 days and hand fed to pelletized diets three times a day until apparent satiation. Diets with approximately 302 g kg−1 of digestible protein and 15.2 kJ g−1 of digestible energy with graded levels of dibasic phosphate yield AP levels of 2.39, 4.17, 6.12 and 8.91 g kg−1. At the end of the trial, feed intake, hepatosomatic index, fillet yield, whole body moisture and crude protein of fish fed 2.39–8.91 g kg−1 of AP diets were not significantly different. The supplementation of 6.12 and 8.91 g kg−1 of AP resulted in significantly increased weight gain, whole body ash and calcium. Whole body crude lipids significantly decreased with increasing AP from 6.12 to 8.91 g kg−1. However, concentration of zinc in the vertebrae was not affected by dietary treatments. The magnesium contents of the fish vertebrae were lower in fish fed lower dietary AP level. No effects of the dietary AP on apparent digestibility coefficients of energy and nutrients were observed. The study indicated that the dietary AP level of at least 6.12 g kg−1 satisfies the needs for growth performance, body composition and bone mineralization of large Nile tilapia.

The effects of linseed oil (LO) and macadamia oil (MO) on the metabolic changes induced by a high-fat diet (HFD) rich in saturated fatty acid were investigated. For the purpose of this study, the vegetable oil present in the HFD, i.e. soybean oil (SO) was replaced with LO (HFD-LO) or MO (HFD-MO). For comparative purposes, a group was included, which received a normal fat diet (NFD). Male Swiss mice (6-week old) were used. After 14 days under the dietary conditions, the mice were fasted for 18 h, and experiments were then performed. The HFD-SO, HFD-LO and HFD-MO groups showed higher glycaemia (p

Objetivou-se, no presente experimento, comparar o efeito da origem da fonte protéica e da suplementação com lisina e metionina ou cálcio e fósforo para a tilápia do Nilo (Oreochromis niloticus), durante a reversão sexual. Foram utilizadas 200 larvas, distribuídas em 20 aquários de 12 litros, em um delineamento inteiramente casualizado em quatro tratamentos e cinco repetições. A temperatura pela manhã e à tarde, o oxigênio dissolvido, pH e condutividade elétrica da água foram, respectivamente, de 22,6 ± 0,1ºC, 24,1±0,4ºC; 6,77 ± 0,38 mg/L, 7,75 ± 0,16; e 173,4 ± 2 mS/m. Os tratamentos foram compostos por quatro rações isoprotéicas e isoenergéticas: uma somente com ingredientes de origem animal (FA); outra com ingredientes de origem vegetal (FV) e duas com ingredientes de origem vegetal, uma com adição dos aminoácidos lisina e metionina (FAA) e outra com cálcio e fósforo (FP). Os valores médios finais de peso e comprimento dos animais submetidos à ração FA foi superior aos demais tratamentos, seguido pelo FP e FV, que não diferiram da FAA. O tratamento FA apresentou os maior valores de biomassa final, seguido do FP e FAA, que foram semelhantes ao FV. O fator de condição dos peixes do tratamento FA foi superior aos FAA e FV, porém o FP foi semelhante aos demais. A sobrevivência dos tratamentos FA, FV e FP foram semelhantes entre si e superiores ao FAA. Para a fase de reversão sexual da tilápia do Nilo, rações formuladas com ingredientes de origem animal foram mais eficientes que as formuladas com ingredientes de origem vegetal, mesmo quando estas foram suplementadas com lisina e metionina ou cálcio e fósforo. This work aimed to evaluate the effect of protein source origin and lysine and methionine or phosphorus and calcium supplementation to Nile tilapia during sex reversal phase. Two hundred fries were assigned to a completely randomized design with four treatments and five replications, in twenty 12 L aquarium. One aquarium with 10 Nile tilapia fry was considered an experimental unit. Morning and afternoon temperatures, dissolved oxygen, pH and electric conductivity was 22.6 ± 0.1ºC, 24.1± 0.4ºC; 6.77 ± 0.38 mg/L, 7.75 ± 0.16 e 173.4 ± 2 µS/m, respectively. The treatments were diets, one only with protein source of animal origin (FA), other only with protein source plant origin (FV), another with protein source plant origin but supplemented with lysine and methionine (FAA) and other with protein source plant origin but supplemented with calcium and phosphorus (FP). Means of end values of weight and length fry submitted to FA diet was greater than others treatments, followed to FP and FV diets, who had same value that the FAA diet. FA diet showed higher values of final biomass, followed by FP and FAA, that showed the same value of FV diet. Fry condiction of FA diet was greater than FAA and FV, but similar to FP diet. The survival of FA, FV, and FP diets was same and greater than FAA. Diets with animal protein ingredients were more efficient than vegetal protein ingredients with lysine and methionine or calcium and phosphorus supplementation, for Nile tilapia during sex reversion phase.

Objetivou-se avaliar a influência da densidade de estocagem sobre o desenvolvimento do quinguio, Carassius auratus (Osteichthyes, Cyprinidae) em suas fases iniciais. Foram utilizados 300 larvas (Lt = 7,00 mm), distribuídas em 20 aquários (12-L). O delineamento experimental utilizado foi o inteiramente casualizado com quatro tratamentos (0,50; 1,00; 1,50 e 2,00 larvas/L) e cinco repetições. A alimentação utilizada foi à base de náuplios de Artemia sp. (fornecida de forma proporcional a densidade) e ração com 40% de proteína bruta (fornecida à vontade). Observou-se aumento linear (p0,001) pelas diferentes densidades de estocagem utilizadas. Os valores dos parâmetros físico-químicos permaneceram nos níveis adequados para o cultivo de peixes, embora os valores de pH tenham apresentado redução linear (pThis experiment aimed to evaluate the influence of stocking density on the goldfish, Carassius auratus (Osteichthyes, Cyprinidae) development, during its initial phases. 300 fry (Lt.: 7.00 mm) were distributed in 20 12-liter aquariums. The experimental design was entirely randomized, with four treatments (0.50; 1.00; 1.50 and 2.00 fry/liter) and five replications. Food consisted of Artemia sp nauplii (supplied proportionally to density) and rations with 40% raw protein, given ad libitum. While the biomass per aquarium linear increase (p0.001). On the other hand, quadract effect (p 0.001) by the different stocking densities. The physical-chemical parameters rates remained at adequate levels for fish culture, although pH values suffered linear decrease (pCarassius auratus fry culture can use such density during its initial development phases.

Fumonisins are mycotoxins that naturally occur as contaminants in grains that are destined for animal and human consumption. These mycotoxins cause hepatotoxic, nephrotoxic, carcinogenic, teratogenic, immunotoxic, and neurotoxic effects in different intensities based on dose, time of exposure, and animal species. In the present study, male Wistar rats were fed between postnatal days 21 and 63 with diets that contained fumonisins B1+B2 at concentrations of 1 and 3mg/kg. The objective of the present study was to evaluate the effects of fumonisins on food intake, growth, weight gain, serum activity of the alanine aminotransferase and aspartate aminotransferase enzymes, and quantitative and morphometric parameters of myenteric neurons in the jejunum that are immunoreactive to HuC/D protein and neuronal nitric oxide synthase enzyme (nNOS). Diets that contained fumonisins did not significantly alter food intake or body and blood parameters. We did not observe significant differences in the neuronal density and proportion of nitrergic neurons but found a significant reduction of cell body areas in both neuronal populations. This study is the first to report the effects of fumonisins in the enteric nervous system. The possible mechanisms by which fumonisins impair neuronal development and the use of the enteric nervous system as a tool for the study of the neurotoxic effects of fumonisins are discussed. In conclusion, fumonisin-containing food negatively affected the growth of myenteric neurons.

Este estudo foi realizado para avaliar níveis de L-glutamina e L-glutamato em dietas para juvenis de tilápia-do-nilo (0,60 ± 0,1 g). Foi utilizado delineamento inteiramente casualizado com quatro dietas e três repetições e 90 peixes por unidade experimental. Foi utilizada dieta controle, com 29% de proteína digestível e 2.940 kcal/kg de energia digestível, suplementada mistura de L-glutamina e L-glutamato na proporção de 0, 1, 2 e 3% da dieta, durante 85 dias. Não foi observado efeito da L-glutamina e L-glutamato sobre o consumo, a conversão alimentar, a taxa de eficiência protéica, a eficiência de retenção de nitrogênio, o índice hepatossomático, a composição química corporal, a amônia e ureia sanguíneas. O aumento nos níveis de L-glutamina e L-glutamato nas dietas teve aumento linear sobre o ganho de peso e efeito quadrático na altura dos vilos. A adição de L-glutamina e L-glutamato melhora o ganho de peso e a altura das vilosidades intestinais de tilápia-do-nilo. This work was carried out to evaluate levels of L-glutamine and L-glutamate in diets for Nile tilapia juveniles (0.60 ± 0.1 g). A complete randomized experimental design with four diets and three replicates and 90 fish per experimental unit was used. It was used a control diet with 29% of digestible protein and 2,940 kcal/kg of digestible energy supplemented with L-glutamine and L-glutamate at the proportion of 0, 1, 2 and 3% of diet, during 85 days. It was not observed effect of dietary L-glutamine and L-glutamate on feed intake, food conversion, protein efficiency rate, nitrogen retention efficiency, hepatic somatic index, chemical body composition, blood ammonia and urea. It was observed a linear increase on gain weight and a quadratic effet on villus height when levels of L-glutamine and L-glutamate increased. The addition of L-glutamine and L-glutamate increases the weight gain and intestinal villus height of Nile tilapia.

AimsLiver glycogen catabolism was evaluated in male Swiss mice fed a high-fat diet rich in saturated fatty acids (HFD) or normal fat diet (NFD) during one week.Main methodsLiver glycogenolysis (LG) and liver glucose production (LGP) were measured either under basal or stimulated conditions (infusion of glycogenolytic agents). Thus, isolated perfused livers from HFD and NFD mice were infused with glycogenolytic agents, i.e., glucagon, epinephrine, phenylephrine, isoproterenol, adenosine-3′-5′-cyclic monophosphate (cAMP), N6,2′-O-dibutyryl-cAMP (DB-cAMP), 8-bromoadenosine-cAMP (8-Br-cAMP) or N6-monobutyryl-cAMP (N6-MB-cAMP). Moreover, glycemia and liver glycogen content were measured.Key findingsGlycemia, liver glycogen content and basal rate of LGP and LG were not influenced by the HFD. However, LGP and LG were lower (p

We developed a pre-clinical model in which to evaluate the impact of orally administered carbohydrates on postprandial blood glucose levels. For this purpose, we compared the effects of different carbohydrates with well-established glycemic indexes. We orally administered (gavage) increasing amounts (0.2, 0.4, 0.6, 0.8, and 1.0 g/kg) of sucrose and lactose to rats which had been fasted for 6 h or 15 h, respectively. In part of the experiments we administered frutose (gavagem). Three different models were compared for measuring postprandial blood glucose levels: a) evaluation of interstitial glucose concentrations by using a real time continuous glucose monitoring system; b) evaluation of glucose levels in blood obtained from the rat tail; c) evaluation of serum glucose levels in blood collected after decapitation. Our results showed that blood obtained from the tails of 15-h fasted rats was the best model in which to evaluate the effect of carbohydrates on postprandial blood glucose levels.

Fumonisin is a mycotoxin produced during the secondary metabolism of Fusarium verticillioides and Fusarium proliferatum and may cause several injuries and loss in performance in animals that consume them. In this study, the hypothesis that dietary intake of fumonisin affects the growth performance and the apoptotic balance was tested. Two experiments were performed. In the first, fingerlings of Nile tilapia (2.64 ± 0.06g) were fed diets containing different levels of fumonisin (0 mg/kg - control diet, 20 mg/kg, 40 mg/kg and 60 mg/kg) and were evaluated at an average feed intake (FI), weight gain (WG), feed efficiency (FE) and the gene expression of growth hormone receptor (GHR), insulin like growth factor 1(IGF-1), caspase7 (CASP 7) and sphingosine phosphate lyase (SPL) in hepatic tissue. All variables were evaluated at 15 and 30 days of treatment. Diets containing 20, 40 and FB 60 mg/kg diet significantly reduced the GP (p

Inflammation is the first defense of the human organism against tissue injuries. Plants are important sources of bioactive substances and part of its biological activities are attributed to the essential oils. The monoterpenes are the main constituents of the essential oils and have many biological effects. The aim of this study was to evaluate the anti-inflammatory effects of p-cymene and alpha-pinene, plant-derived monoterpene. Therefore, it was evaluated the cytotoxicity by MTT test, acute toxicity in animal models, in vitro neutrophil chemotaxis, in vivo cell migration by peritonitis and mesenteric microcirculation carrageenan-induced. The effects of p-cymene was also evaluated on the phagocytosis ability of the macrophages and cytokine levels. In the cell viability assay, p-cymene and alpha-pinene showed low cytotoxicity (until 90 μg/mL) and absence of acute toxicity at doses up to 3g/Kg. The p-cymene (3, 10, 30, 60 μg/mL) reduced neutrophil migration toward fMLP; decreased the infiltration of total and polymorphonuclear leukocytes into peritoneal cavity (100, 200 and 400 mg/Kg); decreased the number of rolling (100, 200 mg/kg) and adherent leukocytes (100, 200, 400 mg/kg) to the perivascular tissue; increased the macrophage phagocytic index and reduced TNF-α levels. The alpha-pinene (1, 3, 10, 30 g/ml) reduced neutrophil migration toward fMLP and LTB4 stimulation; decreased the infiltration of total and polymorphonuclear leukocytes into peritoneal cavity (200 and 400 mg/Kg) and decreased the number of rolling and adherent leukocytes (200 and 400 mg/Kg) to the perivascular tissue. Our results showed evidences that p-cymene and alpha-pinene have anti-inflammatory effects and may be considered as promising drugs for treatment of inflammatory process with excessive leukocyte migration; however, more studies are needed to elucidate the mechanism action of these monoterpenes. A inflamação é a primeira defesa do organismo humano frente a uma lesão tecidual. As plantas são fontes importantes de substâncias bioativas, e parte de suas atividades biológicas são atribuídas aos óleos essenciais. Os monoterpenos representam os principais constituintes dos óleos essenciais e possuem muitos efeitos biológicos. O objetivo deste trabalho foi avaliar os efeitos anti-inflamatórios dos monoterpenos p-cimeno e alfa-pineno. Para isso, avaliou-se a citotoxicidade pelo ensaio de MTT, a toxicidade aguda em modelo animal, a quimiotaxia de neutrófilos in vitro, a migração celular in vivo através da peritonite e da microcirculação mesentérica induzidas por carragenina. O p-cimeno também foi avaliado frente a capacidade fagocítica de macrófagos e sobre os níveis de citocinas. Nossos resultados demonstraram que o p-cimeno e o alfa-pineno apresentaram baixa citotoxicidade até a dose de 90μg/mL e ausência de toxicidade aguda até 3g/Kg. O p-cimeno (3, 10, 30 e 60 μg/ml) inibiu a quimiotaxia de neutrófilos frente ao fMLP; reduziu a migração de leucócitos totais e polimorfonucleares para a cavidade peritoneal (100, 200 e 400 mg/Kg); reduziu o número de leucócitos rolling (100 e 200 mg/Kg); o número de leucócitos aderentes (100, 200 e 400 mg/Kg); estimulou a capacidade fagocítica de macrófagos (3, 10 e 30 μg/ml) e inibiu a secreção de TNF-α (10 e 90 μg/ml). O alfa-pineno (1, 3, 10 e 30 μg/ml) inibiu a quimiotaxia de neutrófilos frente ao fMLP e ao LTB4; reduziu a migração de leucócitos totais e polimorfonucleares para a cavidade peritoneal (200 e 400mg/Kg) e diminuiu o número de leucócitos rolling e aderentes (200 e 400 mg/Kg). Nossos resultados mostraram evidências de que os monoterpenos p-cimeno e alfa-pineno possuem efeitos anti-inflamatórios, e podem ser considerados drogas promissoras no tratamento de doenças inflamatórias que apresentam uma migração excessiva de leucócitos. Todavia, mais estudos serão necessários para elucidar o mecanismo de ação destes compostos. 59 [2] f

The growth hormone gene (GH) has been a point of study for many researchers because it has been shown that it acts in various physiological processes. Molecular techniques such as sequencing have enabled access to the genomic structure information of GH gene and its polymorphisms, some of these correlated with improved performance and/or production. Tilapia have two GH called GH1 and GH2 their genomic sequences are in the GENBANK database with access numbers of M97766.1 and M97765, respectively, when done the alignment of these sequences we found a high homology. However, there is the repetition of a microsatellite (CTGT) located at two base pairs of the exon 2, the GH1 has seven replications and GH2 has six replications. A pair of specific primers for the GH1 and GH2 genes that amplify a commum region, where the only expected difference are the four base pairs relating to repetition (CTGT) at least, previously described in GH2, shows a difference of approximately 50bp tilapia in some individuals of tilapia, thus defining two types of individuals when using the primer pair, those with a single fragment of 650bp called GHbs (GH single band) and those with two fragments 650pb and 700pb GHbd (GH band double). Given this observation the research objective was to characterize polymorphisms not yet reported GHbs and GHbd by sequencing technique for varieties of GIFT tilapia, Thai, Bouaké and some of its crossings and calculate the frequencies of these polymorphisms . From the results of sequencing GHbs came to be called GH/Ho individuals who are homozygous with the same number of repetitions (CTGT) in GH1 and GH2 and GHbd as GH/He individuals who are heterozygous with different number of repetitions (CTGT) in GH1 and GH2. Thus, the other objectives were to evaluate the relationship between the polymorphisms GH/HO and GH/He with the performance characteristics polymorphisms, assessing the growth of tilapia GIFT x Thai in a period of 150 days and analyze the hyperplastic and hypertrophic growth of white muscle at 30-60-90 and 120 days of age tilapia, being collected right lateral muscle which was insert paraffin for semi-serial cuts and hematoxylin-eosin staining. The results of sequencing revealed that, when made the sequences aliggnments of genotypes GHbs and GHbd these have mutations as transversions, transitions and deletions when compared to the sequences of the GH1 and GH2 genes. It was also described that individuals can be either homozygous (GH/Ho) or heterozygous (GH/He) with respect to the number of the microsatellite repeats (CTGT) in GH1 and GH2. The genotype frequencies in Thai variety and crossing Thai Thai x GIFT showed 50% of GH/HE and GH/Ho, GIFT of fifth generation from a breeding program showed 90% of GH/Ho and crossing GIFT x Bouake (GXB) found up 100% of individuals GH/He. The results of the morphometric and performance was a significant effect of amplification pattern GH/He for final weight (FW), weight gain (WG), total length (TL), head length (CCAB), head weight was observed (PCAB), weight of gutted fish (PPevis) and weight of skinless fillet (pFILE). Histological evaluations of white muscle fibers of the genotypes showed no significant difference in the frequencies for most ages considered. We can conclude that both GH1 and GH2 may have 6 or 7 repeats of microsatellite CTGT, other low-frequency polymorphisms can be found in the studied region of the GH gene in variety GIFT and frequencies of GH/HO or GH/He may be associated with variety. Evaluations of performance the GH/He individuals showed significant differences for some features, however, it takes a study to examine whether there is change in the amino acid or regulatory regions of the GH gene, yet in the growth of white muscle there are no differences between the polymorphisms. O gene hormônio do crescimento (GH) tem sido ponto de estudo para muitos pesquisadores, pois se tem demonstrado que ele atua em vários processos fisiológicos. Técnicas moleculares como o sequenciamento, têm permitido o acesso à informação da estrutura genômica do gene GH e seus polimorfismos, alguns destes relacionados com melhores desempenhos e/ou produção. As tilápias apresentam dois GH chamados de GH1 e GH2 suas sequências se encontram no banco genômico GENBANK, com números de acesso M97766.1 e M97765 respectivamente, quando feito o alinhamento destas sequências, encontramos uma alta homologia. No entanto, observa-se a repetição de um microssatélite (CTGT) localizado a dois pares de bases do éxon 2. O GH1 apresenta sete repetições e o GH2 seis repetições. Um par de primers específicos para os genes GH1 e GH2 que amplificam uma região comum, onde a única diferença esperada são os quatro pares de bases referentes à repetição (CTGT) a menos, anteriormente descrita em GH2, e apresenta uma diferença de aproximadamente 50pb em alguns indivíduos de tilápias, definindo assim, dois tipos de indivíduos quando usado o par de primers: aqueles que apresentam um só fragmento de 650 pb chamados de GHbs (GH banda simples) e os que apresentam dois fragmentos 650pb e 700pb GHbd (GH banda dupla). Ante esta observação, o objetivo da pesquisa foi caracterizar polimorfismos ainda não reportados GHbs e GHbd, por meio da técnica de sequenciamento para variedades de tilápia GIFT, Tailandesa, Bouaké e alguns dos seus cruzamentos e calcular as frequências destes polimorfismos. A partir dos resultados do sequenciamento GHbs, passou a ser chamado GH/Ho indivíduos que se encontram em homozigose com o mesmo número de repetições (CTGT) em GH1 e GH2 e GHbd como GH/He indivíduos que se encontram em heterozigose com número diferente de repetições (CTGT) em GH1 e GH2. Sendo assim, os outros objetivos, como avaliar a relação que existe entre os polimorfismos GH/Ho e GH/He com as características de desempenho, sendo feita avaliação do crescimento de tilápias GIFT x xvii Tailandesa num período de 150 dias e analisar o crescimento hipertrófico e hiperplásico do músculo branco aos 30-60-90 e 120 dias de idade das tilápias, sendo coletado músculo lateral direito que foi incluído em parafina para cortes semi-seriados e coloração hematoxilina-eosina. Os resultados do seqüenciamento mostraram que, quando feitos os alinhamentos das seqüência dos genótipos GHbs e GHbd, estes apresentam mutações pontuais como transversões, transições e deleções, quando comparadas com as seqüências dos genes GH1 e GH2. Também foi descrito que os indivíduos podem estar tanto em homozigose (GH/Ho) ou heterozigose (GH/He) com relação ao número de repetições do microssatélite (CTGT) em GH1 e GH2. As freqüências dos genótipos na variedade Tailandesa e cruzamento GIFT x Tailandesa apresentaram 50% de GH/He e GH/Ho, GIFT da quinta geração proveniente de um programa de melhoramento apresentou 90% de GH/Ho e cruzamentos GIFT x Bouake (GxB) verificou-se 100% de indivíduos GH/He. Nos resultados para as características morfométricas e de desempenho, foi observado efeito significativo do padrão de amplificação GH/He para peso final (PF), ganho em peso (GP), comprimento total (CT), comprimento de cabeça (CCAB), peso de cabeça (PCAB), peso de peixe eviscerado (PPevis) e peso do filé sem pele (PFilé). As avaliações histológicas das fibras musculares brancas dos genótipos não apresentaram diferença significativa nas freqüências para a maioria das idades consideradas. Podemos concluir que, tanto GH1 e GH2 podem apresentar 6 ou 7 repetições do microssatélite CTGT, outros polimorfismos de baixa freqüência podem ser encontrados na região estudada do gene GH na variedade GIFT e as freqüências de GH/Ho ou GH/He podem estar associadas à variedade. Nas avaliações do desempenho, os indivíduos GH/He apresentaram diferenças significativas para algumas características, no entanto, é preciso um estudo que verifique se existe alteração nos aminoácidos ou regiões regulatórias do gene GH, já no crescimento do músculo branco não se encontram diferenças entre os polimorfismos. xix, 62 f