Nano copper in the diet of laying quails: productive performance, metabolism, and tissue concentration.

The study evaluated the use of nano copper in semi-purified diets for laying quails and its effect on performance, metabolic state, and bioavailability. A total of 160 (180-days-old) quails were distributed in a completely randomized design, in a 3x3+1 factorial. The copper sources used were copper sulfate, copper oxide, and nano copper oxide, at levels of 200, 400, and 800 ppm each, totaling nine treatments plus a negative control (with no copper inclusion). The following variables were determined: weight gain, feed intake, egg production, egg weight, hemoglobin, hematocrit, Cu in the tissues and Cu bioavailability. Data were subjected to analysis of variance at 5% probability. The effect of sources and levels, as well as the interaction between the factors were evaluated. When interaction was observed, the effect of sources was evaluated separately by the Tukey's test and the effect of levels by regression, both at 5% probability. Copper nano oxide can be used at up to 800 ppm in the diet of laying quails without altering the productive performance, and with higher bioavailability than conventional copper oxide. Hemoglobin increases with the inclusion of 200 and 400 ppm of nano copper oxide and the hematocrit with 400 ppm.

Genetic parameters for cloacal gland, sexual maturity, reproductive organs weight, and body weight in meat-type quail.

Selection to increase body weight in poultry can hamper reproduction traits and compromise production efficiency. Thus, attention to reproduction traits is essential to improving the sustainability of breeding programs. Data from a domestic quail breeding program for meat production were used to estimate genetic parameters. We analyzed five traits: 4-week body weight, age at sexual maturity for males and females, cloacal gland area, female, and male reproductive organs weights. A multi-trait mixed model analysis with fixed effects of generation/hatch was performed, assuming environmental covariance equals zero for sex-limited traits. Heritability estimates range from low to moderate for male sexual maturity and cloacal gland area, and high for other traits. Intersexual genetic correlation for age at sexual maturity is positive, which can lead to correlated responses in the other sex. Reproductive organs weights are genetically correlated with body weight, but not significantly between sexes and nor with sexual maturity. Genetic correlations for the cloacal gland area were positive with body weight and negative with age at sexual maturity of males and females, demonstrating a potential use of this trait for selection with favorable outcomes in reproduction. The use of the cloacal gland area can be used in the same way as the scrotal circumference in mammals, improving female reproduction traits by selecting a trait recorded in males.

Effect of Citrus Flavonoid on Storage Time and Meat Quality of Pharaoh Quail (Coturnix Pharaoh)

This study investigates the effects of Hesperidin added to quail ration at different rates on some microbiological and physicochemical, lipid peroxidation, and lipid profiles in thigh meat. The current study had a duration of 35 days and used Pharaoh quails (Coturnix Pharaoh). The grouping was done in three treatment groups: Control, HES500, and HES1000 (each group was divided into five subgroups), and 0, 500, and 1000 mg/kg of Hesperidin was added to the basal diet of the groups, respectively. Adding Hesperidin and storage time affected the pH parameter in meat. It affected colour parameters depending upon the added Hesperidin (p<0.05). There was a significant difference in the number of total mesophilic aerobic bacteria (TMAB) in comparison with the control group according to the storage time (p<0.05). Palmitic, α-linolenic, oleic acid, eicosapentaenoic, and docosahexaenoic acids, which are among the individual fatty acids, differed between the control, HES500 and HES1000 groups (p<0.05). Hesperidin addition reduced lipid peroxidation on the 3rd, 5th, and 7th days of storage (p<0.05). Consequently, in direct proportion to the hypothesis at the beginning of the study, it was specified that adding Hesperidin reduced its concentration on lipid oxidation and had a positive effect on meat quality in terms of colour parameters.(AU)

Models for predicting protein requirements for meat quail.

Three experiments were carried out to determine the crude protein requirements for maintenance (CPm) and weight gain (CPg) of meat quail and to develop protein-requirement prediction models. Experiment 1 was conducted to determine CPm by the nitrogen-balance technique. The regression of nitrogen balance on nitrogen intake revealed a CPm requirement of 2.94 g/kg0.75 /day. Experiment 2 was aimed at determining CPm by the comparative-slaughter technique. Retained nitrogen (RN) and nitrogen intake (NI) were quantified considering the metabolic weight of the birds. The linear regression of RN on NI provided a CPm estimate of 6.63 g/kg0.75 /day. Experiment 3 was conducted to determine CPg. The regression of body nitrogen from the carcasses on fasted body weight revealed CPg estimates of 407.68 (0-7 days), 501.76 (8-14 days), 470.40 (0-14 days), 517.44 (15-21 days), 627.20 (22-28 days), 423.36 (29-35 days), and 517.44 mg/g (15-35 days). The protein-requirement prediction models developed for meat quail aged 0-7, 8-14, 0-14, 15-21, 22-28, 29-35, and 15-35 days were CP = 2.94.W0.75  + 0.408.G; CP = 2.94.W0.75  + 0.502.G; CP = 2.94.W0.75  + 0.470.G; CP = 2.94.W0.75  + 0,517.G; CP = 2.94.W0.75  + 0.627.G; CP = 2.94.W0.75  + 0.423.G; CP = 2.94.W0.75  + 0.517.G, respectively, where: W0.75  =  metabolic weight (kg), and G =  daily weight gain (g).

Effects of the Dietary Inclusion of Xylanase on the Performance and Jejunum Morphometry of Meat-Type Quails

The objective of this study was to evaluate the effects of the supplementation of two xylanase products to diets with reduced metabolizable energy fed to meat-type quails during the starter phase (1-14 days). A completely randomized experimental design in a 2 x 3 + 1 factorial arrangement two reduced metabolizable energy (ME) diets, inclusion or not of xylanase, and a control diet with no enzyme addition) was applied, totaling seven treatments with five replicates of 45 quails each. At 14 days of age, jejunum segments were collected for morphometry evaluation. No interaction between the studied factors were detected for performance and jejunal morphometry parameters. Body weight, weight gain, feed intake and feed conversion were not influenced by enzyme inclusion. Reduced ME diets (-70 or -140 kcal/kg) did not affect performance, except for feed intake. Xylanase inclusion increased villus height and villus:crypt ratio. Therefore, xylanase supplementation can be effective in corn and soybean meal-based diets, without causing any impairment in the performance of 1- to 14-day-old quails. Xylanases A and B were more efficient when dietary energy level was reduced in 140 kcal ME/kg, and were also shown to effectively improve the jejunal morphometry of starter meat-type quails.(AU)

Effects of the Dietary Inclusion of Xylanase on the Performance and Jejunum Morphometry of Meat-Type Quails

The objective of this study was to evaluate the effects of the supplementation of two xylanase products to diets with reduced metabolizable energy fed to meat-type quails during the starter phase (1-14 days). A completely randomized experimental design in a 2 x 3 + 1 factorial arrangement two reduced metabolizable energy (ME) diets, inclusion or not of xylanase, and a control diet with no enzyme addition) was applied, totaling seven treatments with five replicates of 45 quails each. At 14 days of age, jejunum segments were collected for morphometry evaluation. No interaction between the studied factors were detected for performance and jejunal morphometry parameters. Body weight, weight gain, feed intake and feed conversion were not influenced by enzyme inclusion. Reduced ME diets (-70 or -140 kcal/kg) did not affect performance, except for feed intake. Xylanase inclusion increased villus height and villus:crypt ratio. Therefore, xylanase supplementation can be effective in corn and soybean meal-based diets, without causing any impairment in the performance of 1- to 14-day-old quails. Xylanases A and B were more efficient when dietary energy level was reduced in 140 kcal ME/kg, and were also shown to effectively improve the jejunal morphometry of starter meat-type quails.

P and Ca requirements for Japanese quail.

Four experiments were conducted to estimate the phosphorus and calcium requirements for weight maintenance and weight gain in Japanese quails during their growth phase from 16 to 36 days. Japanese quails aged 16 days were used for estimating the phosphorous and calcium requirements for weight maintenance or weight gain, with these quails composing each reference slaughter group and the others distributed in a completely randomized design, housed in cages of galvanized wire (33 × 33 × 16 cm) that were stored in acclimatized chambers with specific environmental temperatures. The light programme used during the 20-day experimental period was 24 h of artificial light. Analysis of the data showed that the prediction equations for estimating the phosphorus and calcium requirements for weight maintenance and weight gain of Japanese quails between 16 and 36 days of age were P (g/quail/day) = P0.75 *(9.3695 + 7.7397*T) + 9.70*WG, in which P is the phosphorus requirement, and Ca (g/quail/day) = P0.75 *(363.99 - 8.0262*T) + 28.15*WG, in which Ca is the calcium requirement, P is BW (kg), T is temperature (°C) and WG (g/quail/day).

Sensitivity of breeding values for carcass traits of meat-type quail to changes in dietary (methionine + cystine):lysine ratio using reaction norm models.

Our objective was to evaluate changes in breeding values for carcass traits of two meat-type quail (Coturnix coturnix) strains (LF1 and LF2) to changes in the dietary (methionine + cystine):lysine ([Met + Cys]:Lys) ratio due to genotype by environment (G × E) interaction via reaction norm. A total of 7000 records of carcass weight and yield were used for analyses. During the initial phase (from hatching to day 21), five diets with increasing (Met + Cys):Lys ratios (0.61, 0.66, 0.71, 0.76 and 0.81), containing 26.1% crude protein and 2900 kcal ME/kg, were evaluated. Analyses were performed using random regression models that included linear functions of sex (fixed effect) and breeding value (random effect) for carcass weight and yield, without and with heterogeneous residual variance adjustment. Both fixed and random effects were modelled using Legendre polynomials of second order. Genetic variance and heritability estimates were affected by both (Met + Cys):Lys ratio and strain. We observed that a G × E interaction was present, with changes in the breeding value ranking. Therefore, genetic evaluation for carcass traits should be performed under the same (Met + Cys):Lys ratio in which quails are raised.

Genetic parameters for body weight in meat quail.

The aim of this study was to estimate genetic parameters for BW in meat quail at different ages. A total of 24,382 weight records from 3,652 quail, born between 2009 and 2011, were evaluated. Weekly BW was measured from hatch until 42 d of age. The genetic parameters were estimated by the restricted maximum likelihood method using a multivariate animal model. Heritability of BW ranged from 0.03 to 0.23. Genetic correlations were mainly high and positive. Selection for BW at 28 d of age yielded good indirect genetic progress in BW at 42 d of age.

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.

Searching for phenotypic causal networks involving complex traits: an application to European quail.

BACKGROUND: Structural equation models (SEM) are used to model multiple traits and the casual links among them. The number of different causal structures that can be used to fit a SEM is typically very large, even when only a few traits are studied. In recent applications of SEM in quantitative genetics mixed model settings, causal structures were pre-selected based on prior beliefs alone. Alternatively, there are algorithms that search for structures that are compatible with the joint distribution of the data. However, such a search cannot be performed directly on the joint distribution of the phenotypes since causal relationships are possibly masked by genetic covariances. In this context, the application of the Inductive Causation (IC) algorithm to the joint distribution of phenotypes conditional to unobservable genetic effects has been proposed. METHODS: Here, we applied this approach to five traits in European quail: birth weight (BW), weight at 35 days of age (W35), age at first egg (AFE), average egg weight from 77 to 110 days of age (AEW), and number of eggs laid in the same period (NE). We have focused the discussion on the challenges and difficulties resulting from applying this method to field data. Statistical decisions regarding partial correlations were based on different Highest Posterior Density (HPD) interval contents and models based on the selected causal structures were compared using the Deviance Information Criterion (DIC). In addition, we used temporal information to perform additional edge orienting, overriding the algorithm output when necessary. RESULTS: As a result, the final causal structure consisted of two separated substructures: BW→AEW and W35→AFE→NE, where an arrow represents a direct effect. Comparison between a SEM with the selected structure and a Multiple Trait Animal Model using DIC indicated that the SEM is more plausible. CONCLUSIONS: Coupling prior knowledge with the output provided by the IC algorithm allowed further learning regarding phenotypic causal structures when compared to standard mixed effects SEM applications.