Response of zebrafish to royal jelly supplementation and differences in stocking density

Dietary supplementation with royal jelly (RJ) may improve growth, antioxidant gene expression, and intestinal antioxidant capacity, and possibly mitigate effects of stress induced by high stocking density (HSD) in zebrafish (Danio rerio). Effects of HSD and RJ supplementation on growth performance, antioxidant gene expression, and intestinal antioxidant capacity in zebrafish were investigated. A total of 240 four-month-old zebrafish were used in a 2 x 2 factorial design, with four treatments and three replications. The treatments consisted of normal stocking density (NSD) (1 fish/L) and high stocking density (HSD) (3 fish/L) and an unsupplemented commercial diet (0RJ) and commercial diet supplemented with 10% RJ (10RJ). The experiment lasted 25 days. Daily weight gain, final body length, specific growth rate, and survival were recorded. On day 25, six fish per treatment were euthanised and their intestines analysed for antioxidant capacity, and superoxide dismutase 2 (SOD2) and catalase (CAT) gene expression. There were no effects of diet or SD and diet interaction on growth. High stocking density decreased daily weight gain by 25.31%, body length by 2.70%, and survival by 16.85%. Stocking density (SD) and diet interaction influenced intestinal SOD2 and CAT expression and antioxidant capacity. The HSD/0RJ group had lower antioxidant gene expression and antioxidant capacity than the HSD/10RJ and NSD/0RJ groups. Supplementation with RJ did not mitigate the harmful effects of stocking stress. These results indicate that HSD promotes transcriptional suppression of gene encoding enzymes that form the first line of antioxidant defence, resulting in reduced elimination of toxic substances and occurrence of intestinal oxidative stress.

Dietary supplementation with canthaxanthin and 25-hydroxycholecalciferol on the incubation performance and fertility of European quail breeders

This study assessed the effects of combined supplementation with canthaxanthin (Cx) and 25-hydroxycholecalciferol (25-OH-D₃) on incubation performance, fertility, and chick quality in European quail breeders. A total of 240 birds were distributed in a completely randomized design with 5 diets and 8 replicates. The animals were fed a basal diet containing 50 µg of vitamin D₃ or the basal diet supplemented with 3 ppm Cx and 34.5 µg 25-OH-D₃, 6 ppm Cx, and 69 µg 25-OH-D₃, 9 ppm Cx and 103.5 µg 25-OH-D₃, or 12 ppm Cx and 138 µg 25-OH-D₃. Incubation performance was analyzed in 2 periods (32 and 38 wk). Breeders aged 32 wk produced eggs with higher hatchability (P = 0.024), hatchability of fertile eggs (P = 0.026) and lower initial plus mid embryonic mortality (P = 0.021), whereas 38-week-old breeders generated chicks with a higher length at hatching (P < 0.001) and lower final plus pipped embryonic mortality (P = 0.021). In both age groups, Cx + 25-OH-D₃ levels had a quadratic effect on egg fertility (P < 0.001), hatchability of total (P < 0.001), and fertile eggs (P < 0.001). The fertility and the number of sperm cells in the perivitelline membrane was analyzed in two periods (26 and 40 wk). A quadratic effect of diet and days after mating on both parameters (P < 0.05) was observed. Eggs from supplementing breeders showed a high fertility (P < 0.001) and sperm cell counts (P < 0.001) for up to 7 and 3 d after mating, respectively, then the control group. Moreover, the supplementation of quail breeder diets with 6 ppm Cx + 69 µg 25-OH-D₃ enhances sperm cell longevity in sperm storage tubules, hatchability of total and fertile eggs, fertility, and chick quality, especially in older quail's breeders and reduces embryonic mortality.

Effects of free and dipeptide forms of methionine supplementation on oxidative metabolism of broilers under high temperature

Our previous studies have shown that methionine supplementation could help to attenuate the effects of heat stress on the metabolism of broiler chickens. Here we investigated for the first time the effects of methionine supplementation in the form of DL-methionyl-DL-methionine on broilers subjected to heat stress during the growth phase. Broilers were divided into two groups; one group was reared under thermoneutral conditions and the other under continuous heat stress (30 ± 1 °C, 60% relative humidity). Both groups were subdivided into three dietary treatments: a methionine-deficient (MD) diet, a diet supplemented with free methionine (DL-M), and a diet supplemented with methionine dipeptide (DL-MM). Broilers raised under chronic heat stress had lower feed intake and weight gain than broilers raised under thermoneutral conditions (P < 0.05). There were no differences in animal performance between methionine-supplemented diets (DL-M and DL-MM). Heat-stressed birds had significantly higher heterophil/lymphocyte (H/L) ratio than thermoneutral birds. Under heat stress, broilers fed DL-M and DL-MM diets had lower H/L ratio than birds fed the MD diet. Higher concentrations of carbonylated proteins and lower concentration of reduced glutathione were observed in broilers raised under heat stress. In comparing heat-stressed broilers, we found that birds fed the DL-M diet had lower concentrations of thiobarbituric acid-reactive substances and carbonylated proteins than those fed the MD diet (P < 0.05). Higher expression of glutathione peroxidase (GPX) and glutathione synthetase (GSS) genes was observed in heat-stressed broilers (P < 0.05). Under heat stress, the MD diet increased GPX expression compared with other diets. Under thermoneutral conditions, the DL-M diet resulted in the highest GSS expression. There was a negative correlation between DNA methylation and GPX and GSS expression. Our results showed that supplementation of broiler diets with free methionine or methionine dipeptide may help attenuate the effects of heat stress through enhanced activation of genes related to the glutathione antioxidant system. Methionine effects were found for gene regulation, gene expression, and post-translational processing.

High leucine levels affecting valine and isoleucine recommendations in low-protein diets for broiler chickens

Four experiments were conducted to estimate the optimal standardized ileal digestible (SID) level of branched-chain amino acids in low-protein diets during the starter, grower, and finisher periods, using the response surface methodology, and to study their effects on performance and mRNA expression of genes involved in the mechanistic target of rapamycin (mTOR) pathway of broiler chickens from 8 to 21 D of age. In experiments 1, 2, and 3, a total of 1,500 Cobb male broiler chickens were assigned to 15 diets of a central composite rotatable design (CCD) of response surface methodology containing 5 levels of SID Leu, Val, and Ile with 5 replicate pens of 20 birds each. A 3-factor, 5-level CCD platform was used to fit the second-order polynomial equation of broiler performance. In experiment 4, a total of 540 8-day-old Cobb male broiler chickens were distributed in a completely randomized 2 x 3 x 3 factorial arrangement with 2 SID Leu levels (1.28 or 1.83%), 3 SID Val levels (0.65, 0.90, or 1.20%), and 3 SID Ile levels (0.54, 0.79, or 1.09%) for a total of 18 treatments with 5 replicate cages of 6 birds each. High Leu levels impaired (P < 0.05) gain:feed when birds were fed marginal Val or Ile diets. However, gain:feed was restored when both Val and Ile were supplemented to reach adequate or high levels. High Leu levels increased (P < 0.05) mRNA expression of S6K1 and eEF2 genes only in birds fed high Ile levels. Dietary SID Leu, Val, and Ile levels required for gain:feed optimization in low-protein diets were estimated at 1.37, 0.94, and 0.87% during the starter period; 1.23, 0.82, and 0.75% during the grower period; and 1.15, 0.77, and 0.70% during the finisher phase, respectively. Higher Val and Ile levels are required to optimize the effect of Leu supplementation on mRNA expression of mTOR pathway genes in the pectoralis major muscle of broilers from day 1 to 21 after hatch.

Digestible lysine effects on gene expression by Japanese quails in the pre-laying phase

This study aimed to determine the effects of digestible lysine levels in the diets of Japanese quail (Coturnix coturnix japonica) on performance, blood parameters and the expression of insulin-like growth factor I, and growth hormone receptor (GHR), apolipoprotein A-I (APOA-I), acetyl-CoA-carboxylase (ACC), and fatty acid synthase (FAS) genes. A total of 288 seven-day-old female Japanese quails were randomly assigned to one of three diets that contained 0.8%, 1.10%, or 1.40% digestible lysine. The birds were slaughtered at 42 days old, and relative gene expression was evaluated in the liver by qRT-PCR using the 2-ΔCT method. Lysine supplementation had no effect on weight gain and feed conversion. Abdominal fat was lower in birds supplemented with 0.8% digestible lysine than those supplemented with 1.10% and 1.40%. Increased total cholesterol and triglycerides were elevated in quails that received supplementation of 1.10% digestible lysine compared with the other diets. High density lipoproteins were decreased in birds that received 0.8% digestible lysine. Quails fed with 1.40% digestible lysine had greater expression of GHR and APOA-I than quails fed diets with 0.8 and 1.10% (P <0.05). The greatest expressions of ACC and FAS were observed in the liver of quails fed with 0.8% digestible lysine. The current results suggest that lysine supplementation in the pre-laying phase allows birds to deposit muscle mass to reach the optimal conformation and body fatness that provides an energetic reserve for the productive phase by modulating the expression of genes related to growth and lipid metabolism. Keywords: Coturnix coturnix japonica, growth, growth hormone, lipid synthesis, lipid metabolism

A genome-wide association study for feed efficiency-related traits in a crossbred pig population

Feed efficiency (FE) is one of the most important traits in pig production. However, it is difficult and costly to measure it, limiting the collection of large amount of data for an accurate selection for better FE. Therefore, the identification of single-nucleotide polymorphisms (SNPs) associated with FE-related traits to be used in the genetic evaluation is of great interest of pig breeding programs for increasing the prediction accuracy and the genetic progress of these traits. The objective of this study was to identify SNPs significantly associated with FE-related traits: average daily gain (ADG), average daily feed intake (ADFI) and feed conversion ratio (FCR). We also aimed to identify potential candidate genes for these traits. Phenotypic information recorded on a population of 2386 three-way crossbreed pigs that were genotyped for 51 468 SNPs was used. We identified three loci of quantitative trait (QTL) regions associated with ADG and three QTL regions associated with ADFI; however, no significant association was found for FCR. A false discovery rate (FDR) ≤ 0.005 was used as the threshold for declaring an association as significant. The QTL regions associated with ADG on Sus scrofa chromosome (SSC) 1 were located between 177.01 and 185.47 Mb, which overlaps with the QTL regions for ADFI on SSC1 (173.26 and 185.47 Mb). The other QTL region for ADG was located on SSC12 (2.87 and 3.22 Mb). The most significant SNPs in these QTL regions explained up to 3.26% of the phenotypic variance of these traits. The non-identification of genomic regions associated with FCR can be explained by the complexity of this trait, which is a ratio between ADG and ADFI. Finally, the genes CDH19, CDH7, RNF152, MC4R, PMAIP1, FEM1B and GAA were the candidate genes found in the 1 Mb window around the QTL regions identified in this study. Among them, the MC4R gene (SSC1) has a well-known function related to ADG and ADFI. In this study, we identified three QTL regions for ADG (SSC1 and SSC12) and three for ADFI (SSC1). These regions were previously described in purebred pig populations; however, to our knowledge, this is the first study to confirm the relevance of these QTL regions in a crossbred pig population. The potential use of the SNPs and genes identified in this study in prediction models that combine genomic selection and marker-assisted selection should be evaluated for increasing the prediction accuracy of these traits in this population.

Challenge with fumonisins B1 and B2 changes IGF-1 and GHR mRNA expression in liver of Nile tilapia fingerlings

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 (P<0.0001) and FE (P<0.0001), while GHR and IGF-1 mRNA expression was reduced both at 15 and 30 days of treatment. Feed intake was not affected by diets in any of the evaluated periods. These results indicate that fumonisins (FB1 + FB2) affect the growth of Nile tilapia fingerlings through mechanisms that involve reduction of GHR and IGF-1 expression.

Compositional analysis and physicochemical and mechanical testing of tanned rabbit skins

<p>Chemical composition and physicochemical and mechanical parameters of New Zealand White rabbit tanned skin were evaluated. Skin samples from 70-d-old males, in natura and semi-finished, were collected for evaluation. The in natura treatment comprise skins without any processing, while semi-finished treatment comprise skins after soaking, fleshing, liming, de-liming, purging, degreasing, pickling, tanning, neutralising, re-tanning and dyeing, followed by oiling, drying, stretching and softening. After tanning, samples from the dorsal and flank regions were removed for tensile and physicochemical testing in the longitudinal and transverse directions. A split plot design was used with plot treatments (leather regions: R1=dorsal and R2=flank) and subplots directions (S1=longitudinal and S2=transversal), using 10 examples per treatment. At the end of processing, the leather analysis revealed low moisture (31.76%), protein (46.48%) and fat content (24.95%), and a high ash content (8.58%). Leather presented a pH of 4.9 and contained 2.0% chromium oxide, 25.5% extractable substances in dichloromethane, and these characteristics were coupled with a higher tensile strength (10.84 N/mm2) in the dorsal region. However, samples in the same region proved to have higher elasticity (64.57%) in the longitudinal direction, although there was no difference in the progressive tearing analysis (21.07-23.50 N/mm). Overall, our analyses suggest that, in this case, the tanned leather product does not have sufficient resistance for application in clothing production.</p>

Análises mecânicas e físico-químicas de couros de tilápia, cachara e salmão

Objetivou-se comparar as análises físico-químicas e mecânicas de couros de tilápia do Nilo, cachara e salmão submetidos à mesma técnica de processamento da pele. As peles de tilápias, salmão e cachara foram obtidas da unidade de beneficiamento Smart fish (Rolândia-PR), Empresa Tomita e Tomita (Maringá-PR) e Embrapa (Corumbá-MS), respectivamente. Assim que retiradas dos peixes, foram submetidas ao congelamento para transporte e estocagem até ao momento de realizar o curtimento. As peles para o curtimento, foram descongeladas, descarnadas e submetidas à mesma técnica de processamento e transformadas em couro. O couro de tilápia apresentou a maior espessura, força de carga de ruptura e de tração, o de salmão apresentou a maior resistência ao rasgamento (105,69 N/mm). O couro de cachara apresentou resultados inferiores aos couros de tilápia e salmão quanto a porcentagem de elongação. O couro de salmão apresentou o melhor percentual de óxido de cromo (2,6%), já para a tilápia (2,0%) e para a cachara (1,8%), os valores ficaram abaixo do recomendando para couros curtidos com sais de cromo. Substâncias extraíveis em diclorometano para salmão foi o mais indicado (14,7%), enquanto os demais ficaram acima do valor recomendado, sendo necessário ajustes na formulação para a obtenção de couros de melhor qualidade.

Polymorphism C242T in the Cyp19 gene in meat sheep

Abstract The objective of this study was to evaluate the frequency of C242T polymorphism on the aromatase gene and the allelic and genotypic frequency of these variants in sheep belonging to four breed groups. Blood samples were collected from 187 animals of four breed groups: Dorper, Santa Inês, Texel and White Dorper, originated from herds in the region of Maringá/PR, Brazil. The genomic DNA was extracted using alkaline extraction, with subsequent amplification of the fragments via PCR with specific primer. The samples resulting from amplification were subjected to digestion process using the Dpn II restriction enzyme and to polyacrylamide gel electrophoresis 10.0% and stained with silver nitrate. Three distinct genotypes were observed: homozygous (CC), heterozygous (CT) and homozygous for no cut (TT). The resulting data were analyzed using the POPGENE software with 5% significance. Genotypic frequencies among the breed groups were: Texel (CC - 0.426; CT - 0.511; TT - 0.064), Dorper (CC - 0.073; CT - 0.732; TT - 0.439), White Dorper (CC - 0.021; CT - 0.255; TT - 0.723) and Santa Inês (CC - 0.115; CT - 0.462; TT - 0.423).

Repeatability and genotypic correlations of reproductive and productive traits of crossbred beef cattle dams

Beef cattle production requires reproductive efficiency. However, measures of reproductive traits are not usually collected; consequently, correlated traits that could be used as indicators would be useful. We examined associations between measures of reproductive and productive efficiency that could be used as selection indicators. Data from 194 dams of the genetic groups Angus x Nelore, Caracu x Nelore, and Valdostana x Nelore collected over 4 years were used. The reproductive traits analyzed were days to heat (DH), calving interval (CI), days to calving (DC), and pregnancy rate (PR). The productive traits were dam weight (DW), body condition score (BCS), calf weight (CW), and weaning rate (WR). The effects on the model were: year, genetic group, reproductive status (RS), age, reproductive rest, and breed of bull (CW and WR). Multivariate analyses were performed, using the Bayesian approach via Gibbs sampling. We conclude that the reproductive measures are ineffective as selection indicators, whereas using dam weight may be a good alternative.

Mitochondrial gene expression in the liver and muscle of high and low feed efficiency Japanese quail layers subjected to different environmental temperatures

We evaluated the adenine nucleotide translocator (ANT) and cytochrome oxidase subunit III (COX III) mRNA expressions in the muscle and liver of Japanese quails presenting high and low feed efficiency (FE), and subjected them to three different environmental temperatures: comfort, heat stress (38°C), and cold stress (10°C). ANT mRNA expression was lower in the liver of heat-stressed animals. In the muscle, higher ANT and COX III mRNA expressions were observed in high-FE and cold-stressed animals. In the liver, much higher expression of COX III mRNA was observed in cold-stressed animals. These results suggest a possible correlation between the genes involved in energy production by the mitochondria and FE phenotypes, and that environmental temperature can affect the ANT and COX III mRNA expressions. Japanese quails presenting different FE levels respond differently to environmental stimuli.

Acute heat stress and dietary methionine effects on IGF-I, GHR, and UCP mRNA expression in liver and muscle of quails

This study evaluated the expression of insulin-like growth factor I (IGF-I), growth hormone receptor (GHR), and uncoupling protein (UCP) mRNA in muscle and liver of quails that were in thermal comfort or exposed to heat stress and that were fed diets with or without methionine supplementation. Meat quails were fed a diet that either met the nutritional demands for methionine (MS) or did not meet this demand (methionine-deficient diet, MD). The animals were either kept at a thermal comfort temperature (25°C) or exposed to heat stress (38°C for 24 h starting on the 6th day). RNA was extracted from liver and breast muscle, and cDNA was synthesized and amplified using quantitative reverse transcription-polymerase chain reaction. Animals that were fed the MS diet and remained at the thermal comfort temperature exhibited increased IGF-I mRNA expression in the liver (0.56 AU). The GHR mRNA expression in the liver and muscle was influenced by both the study variables. Animals receiving the MS diet showed higher GHR expression, while increased expression was observed in animals at the thermal comfort temperature. The UCP mRNA expression in the muscle was influenced by both methionine supplementation and heat stress. Higher expression was observed in animals that received the MD diet (2.29 vs 3.77 AU) and in animals kept in thermal comfort. Our results suggest that heat stress negatively affects the expression of growth-related genes and that methionine supplementation is necessary to appropriately maintain the levels of IGF-I, GHR, and UCP transcripts for animal metabolism.

Effects of methionine supplementation on the redox state of acute heat stress-exposed quails

The aims of the present study were to evaluate the possible effects of heat stress (HS) on H2O2 production and to evaluate whether methionine supplementation (MS) could mitigate the deleterious effects on cell metabolism and the redox state induced by oxidative stress. Meat quails (Coturnix coturnix coturnix) were fed a diet that either met the nutritional demands for methionine or did not meet this demand (methionine deficient [MD] diet) for 7 d. The animals were either kept at a thermal comfort temperature (25°C) or exposed to HS (38°C for 24 h, starting on the sixth day). Heat stress induced decreased food intake (P = 0.0140), decreased daily weight gain (P < 0.0001), and increased water intake (P = 0.0211). A higher rate of H2O2 production was observed in HS animals (0.0802 vs. 0.0692 nmol of reactive oxygen species [ROS] produced per minute per milligram of protein; P = 0.0042) and in animals fed with the MD diet (0.0808 vs. 0.0686 nmol of ROS produced per minute per milligram of protein; P = 0.0020). We observed effects of the interaction between diet and the environment on the activities of glutathione peroxidase (GP-x) and catalase (P = 0.0392 and P < 0.0001, respectively). Heat stress induced higher levels of GP-x activity in animals on the MS diet and higher catalase activity in animals on the MD diet. Glutathione (GSH) levels were higher in animals on the MS diet (P = 0.0273) and in animals that were kept in thermal comfort (P = 0.0018). The thiobarbituric acid reactive substances level was higher in HS animals fed with the MD diet (P = 0.0386). Significant effects of the interaction between supplementation and environment were observed on uric acid concentration levels, which were higher in HS animals fed the MS diet (P = 0.008), and on creatine kinase activity levels, which were lower in HS animals fed the MD diet (1,620.33 units/L; P = 0.0442). Our results suggest that under HS conditions, in which H2O2 production is increased, MS was able to mitigate ROS-induced damage, possibly by increasing the activities of antioxidant elements such as GSH, GPx activity, and uric acid concentration, which were present in higher levels in animals that were subjected to HS and fed the MS diet.

Effect of glycerol on GHR and IGF-1 gene expression in breast muscle and on growth of Japanese meat quails

We evaluated messenger RNA (mRNA) expression of the growth-hormone (GHR) and insulin-like growth factor (IGF-1) genes in 28-day-old Japanese meat quails fed diets containing 0, 8, or 12% dietary glycerol in substitution of corn. Total RNA was extracted from the breast muscle and the DNA was amplified with specific primers using real-time PCR. Feed conversion ratio and feed intake were evaluated. The birds fed 8 and 12% glycerol presented higher IGF-1 mRNA expression [0.059 and 0.049 arbitrary units (AU), respectively] relative to those not fed with glycerol (0.029 AU), while 12% glycerol reduced GHR mRNA expression (0.022 AU). Dietary inclusion of 8% glycerol promoted similar performance results (feed conversion) as the diet with no glycerol. We conclude that inclusion of glycerol in the diet affects GHR and IGF-1 gene expression in Japanese meat quails. However, considering the performance results and the expression of the GHR and IGF-1 genes, 8% glycerol may be safely included in the diet of meat quails.

Hambúrgueres de aparas de jacaré-do-pantanal (Caiman yacare) submetidos a diferentes técnicas de defumação

Avaliaram-se hambúrgueres de aparas de jacaré-do-pantanal (Caiman yacare) quanto à composição centesimal, cor e análise sensorial. O delineamento foi inteiramente ao acaso, em três tratamentos: T1= sem defumação; T2= defumação a quente e T3= defumação líquida, e nove repetições. As aparas foram moídas e condimentadas para o hambúrguer. Os hambúrgueres para defumação a quente foram colocados no defumador 60 min a 60ºC com gerador de fumaça por fricção. Foi pulverizada fumaça líquida, sobre os produtos (T3), e estes foram colocados em desidratador por 60 min a 60ºC. Houve diferença significativa quanto à composição centesimal entre os hambúrgueres defumados, T2 = 43,1% e T3 = 60,9%, e verificou-se menor teor de umidade em relação aos sem defumação, 73,3%. A proteína, 39,9%, e as cinzas, 6,1%, foram mais altas nos defumados a quente. Os hambúrgueres defumados a quente apresentaram menor luminosidade, 42,05, e maiores valores do croma a*, 14,65, e b*, 28,57, em relação aos demais tratamentos. As variáveis sensoriais foram significativas para sabor, textura e aceitação geral. Os produtos defumados a quente apresentaram a pior aceitação. Concluiu-se que a defumação a quente proporciona produtos com menor teor de umidade, com pigmentação mais intensa, porém menos aceitos pelos provadores.

The effect of glycerol on mRNA expression of growth hormone, insulin-like growth factor, and mitochondrial breast muscle genes of Japanese quail

1. A study was carried out to evaluate the expression of growth hormone (GH), insulin-like growth factor I (IGF-I), mitochondrial adenine nucleotide translocase (ANT), cytochrome oxidase III (COX III) and avian uncoupling protein (avUCP) genes in 14-d-old Japanese quail that were fed different levels of glycerol (0%, 4%, and 12% dietary glycerol) which replaced maize as an energy source. 2. Total RNA was extracted from the breast muscle, and cDNA was amplified using real-time PCR with primers specific to the examined genes. 3. Quail fed the diet with 12% glycerol supplementation presented higher growth hormone (GH) mRNA expression than did those fed 0% glycerol. Supplementation with 12% glycerol negatively influenced IGF-I mRNA expression and reduced ANT mRNA expression in comparison with the treatment with no glycerol. COX III mRNA expression in the pectoralis superficialis muscle was decreased by 26% in quail fed 12% glycerol compared with those fed 0 and 4% glycerol. 4. There was no difference in UCP mRNA expression between quail fed 0 and 4% glycerol; however, UCP expression was reduced (73%) in birds fed the 12% glycerol diet compared with the level in those fed the 4% glycerol diet. 5. The inclusion of 4% glycerol in the diet produced results similar to those of the diet with no glycerol. Based on quail performance and the expression of the GH, IGF-I, ANT, COX III and UCP genes, 4% glycerol can be used in quail feeding without any harmful effects.

Production of reactive oxygen species, gene expression, and enzymatic activity in quail subjected to acute heat stress

The aim of the present study was to evaluate the effect of acute heat stress on the production of mitochondrial reactive oxygen species (ROS), the gene expression of the avian uncoupling protein (avUCP) and glutathione peroxidase (GPX 7), and the activity of the enzyme GPX in the liver of meat quail. Two groups of 15 meat quail (Coturnix coturnix japonica) that were 23 d of age were initially housed individually in metallic cages. A period of 7 d was provided for the 2 bird groups to adapt to the cages and to a thermoneutral environment at 25°C with 60% relative humidity. At 30 d of age, 15 quail were exposed to a heat stress (HS) treatment of 34°C for 24 h, humidity 60%, whereas control quail (n = 15) were kept at 25°C. To analyze the production of ROS, 4 quail from each treatment group were slaughtered, and their livers were collected for mitochondrial isolation and to measure the subsequent production of ROS by the mitochondria. Additionally, the livers of 6 animals from each treatment group were collected for total RNA extraction. The cDNA was amplified using primers specific for the target genes, and expression was analyzed using the real-time PCR reaction (qRT-PCR). Five animals from each treatment group were slaughtered to analyze glutathione peroxidase (GPx) activity, which was determined by using of hydrogen peroxide (H2O2), and based on measuring the amount nicotinamide adenine dinucleotide phosphate oxidized. A greater amount of mitochondrial ROS was found in HS animals (0.34 vs. 0.22 nm of ROS produced min(-1) · mg(-1) of protein, P < 0.05) for the reactions that contained only rotenone and in the reactions that were performed with rotenone and antimycin (0.31 vs. 0.23 nm of ROS produced min(-1) · mg(-1) of protein, P < 0.05). Concomitantly, the birds that were subjected to acute heat stress and had a greater amount of ROS production expressed less avUCP mRNA [0.75 arbitrary units (AU) vs. 0.87 AU, P < 0.05] and more GPX 7 mRNA (2.37 AU vs. 1.17 AU, P < 0.01). The HS quail displayed significantly greater GPx activity in their hepatocytes (47.8 vs. 39.6 nmol of NADPH oxidized per mg of protein per minute, P < 0.05). Thus, acute heat stress at 34°C for 24 h affects the production of mitochondrial ROS, the expression of avUCP and GPX 7 mRNA, and the activity of the GPx enzyme in the liver of meat quail.

Identification and validation of differentially expressed genes from pig skeletal muscle

Pig is an important animal for meat production; this is generally associated with characteristics determined prenatally during myogenesis. Expressed sequence tags (EST) can provide direct information on the transcriptome and indirect information on the relation between the genome and phenotype, giving information about differentially expressed genes (DEG). In this work, the identification and annotation of DEG from EST libraries of three pig breeds (Duroc, Large White and Local Breed Piau) were performed followed by real-time PCR analyses during pre- and postnatal stages (21, 40, 70 and 90 days of pregnancy and 107, 121 and 171 days postnatal) from commercial breed animals for analysis of genes expression levels. Therefore, 34 genes differentially expressed were identified, of which 21 grouped in a network related with muscle development. From this, the expression profile of 13 genes was measured, to confirm their relationship with myogenesis like ANKRD2, MYBPC1, NEB and MYL2. These genes showed a prenatal high expression in this study. Besides, novels candidates for muscle development (TP53 and DCTN1) were listed. These findings can contribute to better explaining gene function mechanism and are helpful in uncovering the pathways that mediate pre- and postnatal skeletal muscle development in vertebrates.

Comparação das peles de tilápia do nilo, pacu e tambaqui: histologia, composição e resistência

O objetivo deste trabalho foi comparar as peles de tilápia (Oreochromis niloticus), pacu (Piaractus mesopotamicus) e tambaqui (Co-lossoma macroporum) quanto à histologia, composição centesimal, características físico-química e físico-mecânica. Para tanto foram utilizados 10 kg de peles de cada espécie. Todas as peles seguiram a mesma metodologia de curtimento, sendo todas processadas em fulão. Foram realizadas análises histológicas e de composição nas peles in natura, e após o curtimento foram utilizados 20 couros de cada espécie para obtenção dos corpos-de-prova de cada tratamento para análises físico-química e físico-mecânica. A pele de tilápia do Nilo apresentou lamélulas maiores que as demais espécies analisadas, entretanto, a camada mais profunda da derme desta espécie apresenta feixes de fibras colágenas mais finas no sentido transversal a superfície da pele, enquanto nas peles de pacu e tambaqui observou-se fibras colágenas mais espessas no sentido longitudinal e grossos feixes de fibras colágenas no sentido transversal a superfície da pele. A pele de tilápia do Nilo apresentou maior teor de umidade (67,14 %), lipídeos (1,96 %) e cinzas (1,82 %), entretanto a pele dessa espécie foi a que apresentou menor teor de proteína bruta (29,08 %). Maior teor de proteína bruta foi encontrado nas peles de tambaquis (35,70 %). Os couros de tilápia do Nilo apresentaram menor espessura (0,68 mm), resistência à tração (11,86 N/mm2), rasgamento progressivo (40,18 N/mm), menor elasticidade (52,63 %) e menor força máxima (81,06 %) comparada aos couros de pacu e tambaqui. Sendo o couro de tambaqui, o de maior espessura (0,89 mm) e resistência para as variáveis analisadas (tração= 29,49 N/mm2, rasgamento progressivo= 80,01 N/mm e força máxima=224,25). Os couros de tilápia são menos resistentes que os de pacu e tambaqui; os couros de tambaqui, poderiam ser destinados à confecção de vestuários, e os couros das três espécies apresentam a espessura dentro do recomendado para confecção de luvas e vestimentas.

Expression of growth genes in response to glycerol use in Japanese quail diets

Glycerol can be used as a substitute for corn for feeding poultry, but there are concerns about how it may affect growth performance and health of the birds. We evaluated the expression of mRNA of growth hormone (GH) and insulin-like growth factor I (IGF-I) in 35-day-old Japanese quails fed different glycerol levels (0, 4, and 8% dietary glycerol instead of corn). Total RNA was extracted from the breast muscle and cDNA was amplified with the use of specific primers for these genes using real-time PCR. Quails fed the diet with 8% glycerol supplementation had significantly lower GH mRNA and IGF-I mRNA expression than those fed no glycerol or 4% glycerol. No significant effect of the treatments was found on quail weight gain or feed intake. Feed conversion ratio was influenced by dietary glycerol levels: the group fed 8% glycerol displayed the worst feed conversion ratio (2.54) compared with that of quail fed the control diet (2.35) or 4% glycerol (2.36). Considering quail performance and the expression of the genes GH and IGF-I, a level of 4% glycerol can be used in quail feeding without any harmful effects.

Influência do tempo do processo de curtimento na qualidade dos couros de coelhos (o. Cunniculus)

O experimento foi conduzido para avaliar a qualidade dos couros de coelhos em diferentes partes da superfície e orientações, submetidos a dois diferentes tempos de processamento. Foram utilizadas 40 peles de coelhos, da raça Nova Zelândia Branco, abatidos aos 70 dias de idade. Foi utilizado um delineamento inteiramente casualizado em esquema de parcelas subdivididas, tendo nas parcelas os tratamentos (T1= tempo normal; T2= tempo contínuo) e nas subparcelas as posições de corte no couro (P1= anterior longitudinal; P2 = anterior transversal; P3= posterior longitudinal e P4= posterior transversal), com dez repetições por tratamento. As etapas aplicadas no processo de curtimento foram: remolho, descarne, caleiro (3% de sulfeto de sódio e 4% de cal), desencalagem, purga, desengraxe, píquel, curtimento (6% de sais de cromo), neutralização, recurtimento (4% sais de cromo), tingimento, engraxe (6% de óleos sulfatados), secagem e amaciamento. A espessura dos couros foi maior (p

Candidate gene expression and intramuscular fat content in pigs

Seventy-two pigs of three genetic groups (Brazilian indigenous breed Piau, Commercial line and Crossbred) of both sexes were slaughtered at four live weights (30, 60, 90 and 120 kg). Intramuscular fat (IMF) content in Longissimus dorsi muscle of each animal was extracted and correlated with candidate gene mRNA expression (ATN1, EEF1A2, FABP3, LDLR, MGP, OBSCN, PDHB, TRDN and RYR1). Within slaughter weight of 120 kg, Piau and Crossbred pigs showed higher IMF content (p < 0.05) than commercial animals, with 2.48, 2.08 and 1.00% respectively. Barrows presented higher values of IMF (p < 0.05) than gilts (1.54 and 1.30% respectively). Gene expression of EEF1A2, FABP3, LDLR, OBSCN, PDHB, TRDN and RYR1 were correlated with IMF (p < 0.05) using the whole dataset. For Piau data only, expression of FABP3, LDLR, MGP, OBSCN, PDHB, TRDN and RYR1 showed correlation with IMF (p < 0.05). Genes that have important roles in lipid transportation inside the cell (FABP3) and tissues (LDLR) showed correlation with IMF of, respectively, 0.68 and 0.63 using the whole data set, and 0.90 and 0.91 using data from Piau animals. The highly positive correlation of the LDLR and FAPB3 expression with IMF content may confirm that these genes are important for fat deposition in the porcine L. dorsi muscle.

Diversidade genética entre três linhagens de codorna selecionadas para produção de ovos

A diversidade genética entre três linhagens de codorna (Coturnix japônica) foi avaliada utilizando-se a técnica de random amplified polymorphic DNA (RAPD). As linhagens selecionadas para produção de ovos foram identificadas como amarela, azul e vermelha por meio de anilhas no pé esquerdo. Seis primers de RAPD amplificaram 55 loci, os quais geraram padrão de bandas intensa e reproduzível em gel de agarose. Os resultados indicaram polimorfismos dentro e entre as linhagens. A similaridade de Jaccard média e o índice de diversidade Shannon revelaram alta diversidade dentro das linhagens de codornas. O teste de Mantel por meio do algoritmo unweighted pair-group method using arithmetic average (UPGMA) e a dispersão de coordenadas principais indicaram diferenciação genética significativa, embora em baixo nível. Os resultados sugerem que a diversidade genética dentro e entre as linhagens de codornas da Universidade Estadual de Maringá são promissoras para uso em programas de melhoramento.

Frequencia alélica e genotípica do gene DGAT1 em uma população de bovinos de leite

O gene DGAT1 é um gene candidato envolvido com o conteúdo de gordura no leite. Neste estudo foram analisadas amostras de DNA de 72 bovinos leiteiros de uma população parcialmente fechada através amostras de sangue. O DNA foi extraído utilizando CTAB e proteinase K. A região alvo do gene foi amplificada por PCR e os resultados foram visualizados com a utilização de gel de poliacri-lamida. Na população em estudo foi verificada a presença de quatro alelos, cujas frequências foram: A= 4,0%, B= 50%, C= 40%, e D= 6,0%. Foi verificado o equilíbrio de Hardy-Weinberg através do teste de c², concluindo-se que a população não se encontrava em equilíbrio para o locos avaliado.

Caracterización genética de tres líneas de tilapia del Nilo (Oreochromis Niloticus)

El objetivo de este estudio fue analizar la diversidad genética de tres líneas de tilapia del Nilo (Oreochromis niloticus), mediante marcadores RAPDs. Se analizaron 90 individuos adultos (30 de cada línea) de dos piscifactorías ubicadas en las ciudades de Maringá (líneas Bouaké - B y GIFT - G) y Guaíra (línea Chitralada - C), en el Estado del Paraná (Brasil). Los 13 oligonucleótidos seleccionados produjeron 72 fragmentos de los cuales 60 (83,3%) fueron polimórficos. Fueron observadas diferencias (p

Testes físico-mecânicos e físico-químicos do couro da tilápia vermelha

Realizaram-se testes físico-mecânicos e físico-químicos em couro de tilápia vermelha (Oreochromis spp.) a fim de testar a sua resistência. As amostras foram distribuídas em delineamento inteiramente ao acaso com dois tratamentos: no T1, procedeu-se à retirada do corpo-de-prova no sentido longitudinal e, no T2, à retirada do corpo-de-prova no sentido transversal. Para os testes de determinação da resistência à tração, alongamento e rasgamento progressivo, foi utilizado o dinamômetro EMIC, com velocidade de afastamento entre as cargas de 100 ± 20mm/min, em ambiente climatizado (± 23ºC e UR do ar de 50%), por 24 horas. A espessura do couro variou de 0,61 a 0,75mm, mas não houve diferença entre os sentidos analisados. O couro apresentou maior resistência à tração no sentido transversal, 25,89N/mm², (P<0,01), comparado ao sentido longitudinal, 14,20 N/mm². O alongamento foi significativamente (P<0,05) maior no sentido longitudinal, 80,8%, em relação ao transversal, 62,6%. Não houve diferença para o rasgamento progressivo entre os tratamentos. O couro apresentou teor de óxido de cromo de 3,8%, graxa de 15,1% e pH e cifra diferencial de 3,5 e 0,5, respectivamente. Os valores nos testes de resistência e físico-químicos apresentados pelo couro indicam que ele pode ser utilizado para a confecção de vestuário e artefatos de couro em geral.

Produção e qualidade do pasto de coastcross consorciado ou não com amendoim forrageiro com ou sem aplicação de nitrogênio

Avaliaram-se a taxa de acúmulo foliar (TAF), a produção total de forragem (PTF), a composição química da forragem e os valores de digestibilidade in vitro da matéria seca (DIVMS) do coastcross (Cynodon dactylon) e do amendoim forrageiro (Arachis pintoi) em pastagem consorciada. Foram avaliados os tratamentos (parcelas): coastcross + A. pintoi sem nitrogênio (CA0); coastcross + A. pintoi com 100kg de nitrogênio (CA100); coastcross com 200kg de nitrogênio (C200) e coastcross + A. pintoi com 200kg de nitrogênio (CA200), e as estações (subparcelas) do ano inverno, primavera, verão e outono. Utilizou-se um delineamento experimental em blocos ao acaso, em esquema de parcelas subdivididas no tempo, com duas repetições. Os tratamentos com os maiores níveis de adubação de nitrogênio apresentaram TAF mais alto que os demais (P<0,05). No verão ocorreu a maior PTF, seguida da primavera, outono e inverno, mas estes não diferiram entre si. Não houve diferença (P>0,05) entre os tratamentos para as variáveis proteína bruta, fibra em detergente neutro e digestibilidade in vitro de matéria seca, tanto para as frações de folhas do coastcross, como para a planta inteira do A. pintoi. A adubação nitrogenada, quando aplicada à pastagem de coastcross singular ou associada ao amendoim forrageiro, proporcionou aumento da TAF e da PTF, com maior produtividade e qualidade no verão.

Diferentes tipos de sacos para análise da digestibilidade in vitro de forrageiras

O trabalho teve como objetivo avaliar a digestibilidade in vitro da matéria seca (DIVMS) e da fibra em detergente neutro (DIVFDN) de diferentes forrageiras no fermentador ruminal da ANKOM® (Daisy II), empregando-se diferentes materiais para a confecção dos filtros usados na digestibilidade: náilon (N) e tecido não tecido (TNT) comparado à testemunha (ANKOM®-F57) (T). As médias de DIVMS e DIVFDN dos tratamentos N e TNT, superestimam os valores obtidos com o material padrão T. Desta forma, comparando a eficiência dos materiais TNT e N, utilizados como alternativos, observa-se que é possível utilizar os mesmos na substituição do saco T, desde que sejam corrigidos através de equações estabe-lecidas neste experimento.

Genetic evaluation of the HSP70 protein in the Japanese quail (Coturnix japonica)

Heat stress is one of the main problems in modern aviculture, since it affects birds especially in the final phase of rearing, causing bird mortality and economic losses to the aviculturist. The quail, as most birds, has difficulties in dissipating heat. However, little is known about the mechanism that controls the responses of the organism to stressor agents. Therefore, the study of heat shock proteins (HSPs) in these birds is important. A 960-bp portion of HSP70 was amplified using oligonucleotide primers specific for chickens. The fragment was sequenced, since it was the same protein, although some modifications have been observed. It showed 98% homology with HSP70 stress protein in Gallus gallus and 99% homology with Numida meleageris.

Karyotypic characterization by mitosis, meiosis and C-banding of Eriopis connexa Mulsant (Coccinellidae: Coleoptera: Polyphaga), a predator of insect pests

Eriopis connexa presents a chromosome number of 2n = 18 + XX for most females analyzed and a meioformula of n = 9 + Xyp for all males. A small metacentric B chromosome restricted to females occurred in 10% of our sample and, when submitted to C-banding, it was shown to be almost completely euchromatic. Chromosome pairs 2 and 3 had satellites and probably contained the nucleolar organizer regions (NORs). C-band analysis also revealed that the constitutive heterochromatin was localized in the centromeres of all chromosomes in the complement.