USO DE GENES CANDIDATOS NO TAMANHO DA LEITEGADA

A suinocultura no Brasil ocupa lugar de destaque na produção de alimentos para consumo interno, e também para exportação. Os avanços ocorridos na genética na área da suinocultura podem ser considerados como fatores primordiais para que a mesma viesse a se mostrar como um importante setor da agropecuária brasileira. As características reprodutivas são essenciais para o desenvolvimento da produção, dentre essas, uma que se mostra bastante importante é o tamanho da leitegada. O uso de genes candidatos pode ser um método promissor na questão reprodutiva de suínos. Vários genes têm sido testados para este fim, como o gene receptor do estrogênio, a proteína 4 de ligação a retinol (RBP4), o receptor da melatonina, o gene receptor da prolactina. E ainda outros genes de caráter importante na reprodução dos animais domésticos, como a Prostaglandina Endoperoxidase Sintetase 2, o gene ligado ao hormônio fator de crescimento epidérmico (EGF) e o hormônio folículo estimulante beta (FSHß). O uso de genes candidatos se faz necessário já que os mesmos são ferramentas potentes para a seleção de genótipos superiore

SEQUENCIAMENTO DO EXON I DO GENE DO HORMÔNIO DO CRESCIMENTO (GH) EM CODORNAS

O hormônio do crescimento (GH) é um hormônio sintetizado e secretado pela hipófise e está envolvido em uma série de processos fisiológicos importantes. Há relatos de polimorfismo no gene GH e associado com a produção de leite, ovos, carne, além de algumas características relacionadas à reprodução. Neste estudo, foi observada alta homologia entre o fragmento seqüenciado em uma linhagem de codorna de corte e os fragmentos depositados no GenBank, sendo verificadas mutações pontuais como transversões e transições, além de deleções e inserções de bases.  No exon I, na região 5´UTR, foram observados polimorfismos que podem ser utilizados em estudo de associação com características de interesse econômico

Effect of slaughter weight on the quality of Nile tilapia fillets

The objective of this work was to evaluate the influence of slaughter weight on the expression of calpastatin, mcalpain and the RyR3 gene, and on the chemical composition, morphometric measurements, fillet yield and sensorial characteristics of Nile tilapia fillets. In the experiment, 90 Nile tilapia were divided into three experimental treatments regarding slaughter weight (n = 30): in treatment 1, tilapia aged 140 days were slaughtered with an average body weight of 665 ± 85 g; in treatment 2, the animals were slaughtered at 182 days and weighed 1000 ± 177 g; and in treatment 3, they were slaughtered at 238 days and weighed 1325 ± 167 g. There was no significant difference (P > .05) between the treatments for the chemical composition and fillet yield. Fillets of tilapia slaughtered with a weight of 665 g presented higher expression of mcalpain and lower expression of calpastatin gene, lower pH values of the thawed fillet, lower drip and thawing loss, and lower shear force than animals slaughtered with the highest evaluated weight. Tilapias slaughtered at 665 g also presented higher flavor and general acceptance. These results show that slaughter weight may influence important aspects of the quality of Nile tilapia fillets and that the slaughter of Nile tilapia with a body weight of 665 g allows fillets that serve the consumer market to be obtained.This work was supported by the Conselho Nacional de Desenvolvimento Científico e Tecnológico – CNPq, Brazil. This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brazil (CAPES) – Finance Code 001.info:eu-repo/semantics/publishedVersio

Effect of prenatal ambient temperature on the performance physiological parameters, and oxidative metabolism of Japanese quail (Coturnix coturnix japonica) layers exposed to heat stress during growth

A strategy to mitigate the negative effects of stress on animals is to enhance their ability to beneficially respond to stressful conditions. This study aimed to assess whether prenatal ambient temperature influences the response of Japanese quail (Coturnix coturnix japonica) chicks to environmental challenges during growth. The experiment was conducted in a 2 × 2 factorial arrangement: two temperature conditions for the mothers (thermoneutral and heat stress by continuous exposure to 32 °C) and two offspring ambient temperature conditions (thermoneutral and heat stress by intermittent exposure to 34 °C for 6 h/day from 15 to 35 days of age). Heat stress in mothers led to lower laying rate, egg mass, expression of methionine sulfoxide reductase A (MSRA) gene, and antioxidant capacity as well as higher chick mortality rate (1–15 days of age). Maternal heat stress led to lower weight gain and total antioxidant capacity and higher feed conversion ratio. Maternal temperature × Offspring temperature interaction effects were observed on carbonylated protein content and HSP70, GSS, and MSRA gene expression. It was observed that, for chicks hatched from heat-stressed mothers, exposure to heat stress led to higher carbonylated protein content and HSP70 expression than exposure to thermoneutral conditions. Maternal heat stress was also responsible for increasing GSS expression in chicks grown under thermoneutral conditions. Chicks hatched from non-stressed mothers and subjected to heat stress had higher MSRA expression compared to chicks maintained in a thermoneutral environment. Our results show that, although maternal heat stress had no negative effects on performance or oxidative metabolism of offspring grown under thermoneutral conditions, it was associated with lower performance and higher protein oxidation in offspring exposed to heat stress during growth. These results could be due in part to alterations in the expression of genes related to antioxidant capacity

Farinha de carcaça de tilápia do Nilo em dietas para coelhos: desempenho e lipídeos séricos

This study aimed to determine the performance and serum lipids of rabbits with 35 to 65 days of age fed with diets enriched with meal filleting residue of Nile tilapia (Oreochromis niloticus). The rabbits were randomly allocated to five treatments with the inclusion of different levels of meal (0, 1, 2, 3 and 4%) in the ration. Diets were formulated to meet the requirements for growing animals. At slaughter blood was collected from each animal in the right jugular vein for analysis of serum lipids. There was no statistical difference in animal performance (P<0.05) on HDL-cholesterol with the inclusion of meal filleting residue of Nile tilapia in the diet whose equation was ŷ=22+1.88Xi R2 = 0.87. The was a difference in the amount of blood calcium in treatment 1% (11.04 mg/dl) and 3% (11.09 mg/dl) of meal filleting residue of Nile tilapia. The inclusion of the meal did not influence the animal performance, but it altered the serum lipid profile. Este trabalho teve o objetivo de determinar o desempenho zootécnico e os lipídeos séricos de coelhos com 35 a 65 dias de idade, alimentados com dietas enriquecidas com farinha de resíduos de filetagem de tilápia do Nilo (Oreochromis niloticus). Os  coelhos  foram distribuídos ao acaso em cinco tratamentos, sendo as dietas diferenciadas pelos níveis de inclusão da farinha (0, 1, 2, 3 e 4%) na ração. As dietas foram balançeadas, atendendo ás exigências para animais em crescimento. No abate, foi coletado o sangue de cada animal direto da veia jugular, para as análises de lipídeos séricos. Não houve diferença estatística para o desempenho dos animais (P>0,05). A análise de lipídeos séricos, indicou um aumento linear (P<0,05) do HDL-colesterol à medida que aumentou a inclusão da farinha de resíduo de filetagem de tilápia do Nilo na ração, cuja equação foi ŷ=22+1,88Xi, R2 = 0,87. Houve diferença no valor de cálcio sanguíneo nos tratamentos 1% (11,04 mg/dl) e 3% (11,09 mg/dl) de inclusão de farinha de resíduos de filetagem de tilápia do Nilo.  A inclusão da farinha não influenciou o desempenho zootécnio, porém alterou o perfil de lipídeo sérico.&nbsp

Efeito da inclusão do blend de óleos essenciais no desempenho e na expressão do gene HSP70 em frangos de corte sob estresse térmico crônico

The objective of this study was to evaluate the effects of the inclusion of a blend of essential oils (capsaicin, carvacrol, cinnamaldehyde and eugenol) in broiler submitted to thermal stress. Performance parameters and gene expression of heat shock protein (HSP70) were evaluated in the liver and jejunum. Regarding performance, animals subjected to heat stress had lower feed intake and weight gain and higher feed conversion. The inclusion of 3% of the blend increased the HSP70 gene expression in jejunum and liver of 42 days old broiler chickens.El objetivo de este estudio fue evaluar los efectos de la inclusión de una mezcla de aceites esenciales (capsaicina, carvacrol, cinamaldehído y eugenol) en pollos de engorde sometidos a estrés térmico. Los parámetros de rendimiento y la expresión génica de la proteína de choque térmico 70 kDa (HSP70) se evaluaron en el hígado y el yeyuno. En cuanto al rendimiento, los animales sometidos a estrés por calor crónico tuvieron menor consumo de alimento y ganancia de peso y mayor conversión alimenticia. La inclusión del 3% de la mezcla en la ración aumentó la expresión del gen HSP70 en yeyuno e hígado de pollos de engorde de 42 días de edad.O objetivo deste estudo foi avaliar os efeitos da inclusão de um blend de óleos essenciais (capsaicina, carvacrol, cinamaldeído e eugenol) em frangos de corte submetidos a estresse térmico. Foram avaliados os parâmetros de desempenho e expressão do gene da proteína de choque térmico (HSP70) no fígado e jejuno. Em relação ao desempenho, os animais submetidos ao estresse térmico tiveram menor consumo de ração e ganho de peso e maior conversão alimentar. A inclusão de 3% aumentou a expressão do gene HSP70 no jejuno e fígado de frangos de corte de 42 dias de idade

The role of cinnamon as a modulator of the expression of genes related to antioxidant activity and lipid metabolism of laying quails

Since cinnamon has vitamins and minerals in addition to antioxidants compounds in its chemical composition studies have shown the potential of cinnamon supplementation on some important characteristics in the performance of birds. Thus, this study was conducted under the hypothesis that the inclusion of cinnamon in the laying quail diet could influence the performance of the birds through the expression of genes related to antioxidant activity and lipid metabolism. To test this hypothesis, 144 Japanese quail (Coturnix japonica) with an initial age of 18 weeks and average weight of 133g were distributed in a completely randomized design with two treatments: no cinnamon supplementation (NCS—control group) and with supplementation of 9g/kg of cinnamon powder (CPS). The experiment lasted for 84 days. At the end of the experimental period, six animals from each treatment were euthanized by cervical dislocation, blood was collected and organs weighed. Liver tissue was collected for gene expression and biochemical analyses. We observed a significant effect of cinnamon inclusion on the weight of the pancreas (P = 0.0418), intestine (P = 0.0209) and ovary (P = 0.0389). Lower weights of the pancreas and intestine, and a higher ovary weight was observed in birds receiving the CPS diet. Quails fed with cinnamon supplementation also had better feed conversion per egg mass (2.426 g /g, P = 0.0126), and higher triglyceride (1516.60 mg/dL, P = 0.0207), uric acid (7.40 mg/dL, P = 0.0003) and VLDL (300.40 mg/dL, P = 0.0252) contents. A decreased content of thiobarbituric acid reactive substances (TBARS) and lower catalase activity was observed in the liver of quails from the CPS diet (0.086 nmoles/mg PTN, and 2.304 H2O2/min/mg PTN, respectively). Quails from the CPS group presented significantly greater expression of FAS (fatty acid synthase, 36,03 AU), ACC (Acetyl-CoA Carboxylase, 31.33 AU), APOAI (apolipoprotein A-I, 803,9 AU), ESR2 (estrogen receptor 2, 0.73 AU) SOD (superoxide dismutase, 4,933.9 AU) and GPx7 (glutathione peroxidase 7, 9.756 AU) than quails from the control group. These results allow us to suggest that cinnamon powder supplementation in the diet of laying quails can promote balance in the metabolism and better performance through the modulation of antioxidant activity and the expression of genes related to lipid metabolism

Genetic responses of inbred chicken lines illustrate importance of eIF2 family and immune-related genes in resistance to Newcastle disease virus

Newcastle disease virus (NDV) replication depends on the translation machinery of the host cell; therefore, the eukaryotic translation initiation factor 2 (eIF2) gene family is a likely candidate for control of viral replication. We hypothesized that differential expression of host genes related to translation and innate immune response could contribute to differential resistance to NDV in inbred Fayoumi and Leghorn lines. The expression of twenty-one genes related to the interferon signaling pathway and the eIF2 family was evaluated at two- and six-days post infection (dpi) in the spleen from both lines, either challenged by NDV or nonchallenged. Higher expression of OASL in NDV challenged versus nonchallenged spleen was observed in Leghorns at 2 dpi. Lower expression of EIF2B5 was found in NDV challenged than nonchallenged Fayoumis and Leghorns at 2 dpi. At 2 dpi, NDV challenged Fayoumis had lower expression of EIF2B5 and EIF2S3 than NDV challenged Leghorns. At 6 dpi, NDV challenged Fayoumis had lower expression of EIF2S3 and EIF2B4 than NDV challenged Leghorns. The genetic line differences in expression of eIF2-related genes may contribute to their differential resistance to NDV and also to understanding the interaction between protein synthesis shut-off and virus control in chickens.This article is published as Del Vesco, Ana Paula, Michael G. Kaiser, Melissa S. Monson, Huaijun Zhou, and Susan J. Lamont. "Genetic responses of inbred chicken lines illustrate importance of eIF2 family and immune-related genes in resistance to newcastle disease virus." Scientific Reports 10 (2020): 6155. doi: 10.1038/s41598-020-63074-9.</p