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Context: Methionine (Met) is an essential amino acid in pig diets. However, high blood homocysteine concentration, a risk factor for cardiovascular disease, can arise from high dietary Met intake and may indicate an imbalance in the Met cycle. Vitamin B6 acts as a cofactor for enzymes associated with the trans-sulfuration pathway, considered the major elimination route of excess homocysteine. Aims: We evaluated the effects of different levels of dietary Met and vitamin B6 supplementation and their interaction with respect to growth performance, blood parameters and metabolic-enzyme gene expression of finishing pigs. Methods: Fifty-six crossbred barrows, averaging 75.11 ± 1.84 kg bodyweight (BW), were assigned in a completely randomised block design arranged in a 2 × 4 factorial with two levels of vitamin B6 supplementation (1.58 and 3.58 mg/kg) and four levels of standardised ileal digestible (SID) Met + cystine (Cys) (0.35%, 0.45%, 0.55 and 0.65%), with seven replicates and one animal per pen, for an average duration of 26 days. BW of each pig and quantity of experimental diets on-offer and consumed were recorded at the beginning and end of the experiment. Plasma concentrations of glucose, urea, total proteins, creatinine and triacylglycerol were determined by the colourimetric method, and serum homocysteine by chemiluminescence. Gene expression was measured by quantitative real-time polymerase chain reaction. Key results: No interactions (P > 0.05) between vitamin B6 supplementation and SID Met + Cys levels were observed for growth performance, blood parameters or metabolic-enzyme gene expression. Higher vitamin B6 supplementation (3.58 mg/kg) improved (P = 0.05) the feed : growth ratio. Treatments did not affect (P > 0.05) expression of the enzymes methionine synthase or cystathionine γ-lyase, and there was a linear increase (P = 0.01) in serum homocysteine levels with increasing dietary Met + Cys. Increasing vitamin B6 supplementation (3.58 mg/kg) in finishing pig diets increased plasma glucose concentration (P = 0.05), but did not mitigate the increase in homocysteine concentration. Conclusions: Overall, a dietary SID Met + Cys intake of 10.46 g/day (corresponding to 0.35%) was sufficient for the growth of finishing barrows from 75 to 100 kg BW. Vitamin B6 supplementation at 3.58 mg/kg improved the feed : growth ratio but was not effective for metabolising the increasing homocysteine concentration via the trans-sulfuration pathway. Implications: This study provides much needed empirical data on the dietary SID Met + Cys requirements for finishing pigs, and the metabolism of these amino acids. High intake of methionine (Met) or deficiency of a vitamin acting on its metabolic pathway (e.g. vitamin B6) can cause high blood homocysteine concentrations. Supplementation with vitamin B6 at 3.58 vs 1.58 mg/kg improved feed conversion of finishing pigs but did not improve the metabolisation of increased blood homocysteine caused by higher levels of standardised ileal digestible Met +cystine (SID Met + Cys). Thus, the main contribution of this study is the data it provides about the required levels of dietary SID Met + Cys associated with vitamin B6 supplementation for finishing pigs. [ABSTRACT FROM AUTHOR]

Context: Methionine (Met) is an essential amino acid in pig diets. However, high blood homocysteine concentration, a risk factor for cardiovascular disease, can arise from high dietary Met intake and may indicate an imbalance in the Met cycle. Vitamin B6 acts as a cofactor for enzymes associated with the trans-sulfuration pathway, considered the major elimination route of excess homocysteine. Aims: We evaluated the effects of different levels of dietary Met and vitamin B6 supplementation and their interaction with respect to growth performance, blood parameters and metabolic-enzyme gene expression of finishing pigs. Methods: Fifty-six crossbred barrows, averaging 75.11 ± 1.84 kg bodyweight (BW), were assigned in a completely randomised block design arranged in a 2 × 4 factorial with two levels of vitamin B6 supplementation (1.58 and 3.58 mg/kg) and four levels of standardised ileal digestible (SID) Met + cystine (Cys) (0.35%, 0.45%, 0.55 and 0.65%), with seven replicates and one animal per pen, for an average duration of 26 days. BW of each pig and quantity of experimental diets on-offer and consumed were recorded at the beginning and end of the experiment. Plasma concentrations of glucose, urea, total proteins, creatinine and triacylglycerol were determined by the colourimetric method, and serum homocysteine by chemiluminescence. Gene expression was measured by quantitative real-time polymerase chain reaction. Key results: No interactions (P > 0.05) between vitamin B6 supplementation and SID Met + Cys levels were observed for growth performance, blood parameters or metabolic-enzyme gene expression. Higher vitamin B6 supplementation (3.58 mg/kg) improved (P = 0.05) the feed : growth ratio. Treatments did not affect (P > 0.05) expression of the enzymes methionine synthase or cystathionine γ-lyase, and there was a linear increase (P = 0.01) in serum homocysteine levels with increasing dietary Met + Cys. Increasing vitamin B6 supplementation (3.58 mg/kg) in finishing pig diets increased plasma glucose concentration (P = 0.05), but did not mitigate the increase in homocysteine concentration. Conclusions: Overall, a dietary SID Met + Cys intake of 10.46 g/day (corresponding to 0.35%) was sufficient for the growth of finishing barrows from 75 to 100 kg BW. Vitamin B6 supplementation at 3.58 mg/kg improved the feed : growth ratio but was not effective for metabolising the increasing homocysteine concentration via the trans-sulfuration pathway. Implications: This study provides much needed empirical data on the dietary SID Met + Cys requirements for finishing pigs, and the metabolism of these amino acids. High intake of methionine (Met) or deficiency of a vitamin acting on its metabolic pathway (e.g. vitamin B6) can cause high blood homocysteine concentrations. Supplementation with vitamin B6 at 3.58 vs 1.58 mg/kg improved feed conversion of finishing pigs but did not improve the metabolisation of increased blood homocysteine caused by higher levels of standardised ileal digestible Met +cystine (SID Met + Cys). Thus, the main contribution of this study is the data it provides about the required levels of dietary SID Met + Cys associated with vitamin B6 supplementation for finishing pigs. [ABSTRACT FROM AUTHOR]

Buffalo milk production has become of significant importance on the world scale, however, there are few studies involving biotechnological tools specifically for buffalo. To verify the effects caused by subclinical mastitis on the components of milk and to study the innate immune system in the udder of dairy buffaloes with subclinical mastitis, we evaluated the levels of expression of the lactoferrin (LTF), tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β), interleukin-8 (IL-8), and toll-like receptors 2 (TLR-2) and 4 (TLR-4) genes in buffaloes with and without subclinical mastitis. Milk samples were collected for the determination of milk components: somatic cell score (SCS), fat, protein, lactose, total solids and solids-not-fat (SNF), as well as for RNA extraction of milk cells, complementary DNA synthesis, and expression profile quantification by quantitative real-time PCR. For gene expression, the ΔΔCt was estimated using contrasts of the target genes expression adjusted for the expression of the housekeeping genes between both groups. Linear regression analysis was performed to determine the relationship between the genes studied and the milk components. Subclinical mastitis induced changes in the fat, lactose and SNF in milk of buffaloes, and the messenger RNA abundance was upregulated for TLR-2, TLR-4, TNF-α, IL-1β and IL-8 genes in milk cells of buffaloes with subclinical mastitis, whereas the LTF gene was not differentially expressed. Results of linear regression analysis showed that TLR-2 gene expression most explains the variation in SCS, and the change in a unit of ΔCt of the TNF-α gene would result in a higher increase in SCS. The study of these immune function genes that are active in the mammary gland is important to characterize the action mechanism of the innate immunity that occurs in subclinical mastitis in dairy buffaloes and may aid the development of strategies to preserve the health of the udder. [ABSTRACT FROM AUTHOR]

We evaluated the effects of heat stress (HS) and methionine supplementation on biological markers of stress and expression of the genes for superoxide dismutase (SOD), thioredoxin (TRx), thioredoxin reductase 1 (TRxR1) and methionine sulfoxide reductase A (MsrA) in broilers aged 1 to 21 or 22 to 42 days. The broilers were divided into two treatments, one with the recommended level of methionine supplementation (MS, supplementation of dl-2-hydroxy-4-methylthiobutanoic acid (dl-HMTBA)) and one without methionine supplementation (MD). The animals were maintained at a temperature of thermal comfort or one of HS (38°C for 24 h). Mortality was only observed in 42-day-old broilers exposed to HS and fed the MD diet, and the rate was 5%. Starter period: we observed an interaction effect between diet and temperature on the gene expression of TRxR1 and MsrA, and expression of these genes was higher in the HS animals that received the MS diet than that in birds with the MD diet. Grower period: the expression of SOD, TRxR1 and MsrA genes, activities of aspartate aminotransferase (AST) and creatine kinase (CK) and content of creatinine were influenced by both study variables. In the HS animals, the expression of these genes, AST activity and creatinine content increased and CK activity decreased. In the animals on the MD diet, the expression of these genes and AST and creatinine values were higher and the CK activity was lower than those for the birds on the MS diet. Our results indicated that under HS conditions, the supplementation with dl-HMTBA could mitigate major damage caused by stress through the action on some genes related to TRx complex activity. [ABSTRACT FROM AUTHOR]

We aimed to evaluate the effects of acute heat stress (HS) and age on the redox state in broilers aged 21 and 42 days. We evaluated the expression of genes related to antioxidant capacity, the production of hydrogen peroxide (H2O2), and the activity of antioxidant enzymes in the liver, as well as oxidative stress markers in the liver and plasma. The experiment had a completely randomized factorial design with two thermal environments (thermoneutral and HS, 38°C for 24 h) and two ages (21 and 42 days). Twenty-one-day-old animals exposed to HS showed the highest thioredoxin reductase 1 (TrxR1) (P<0.0001) and glutathione synthetase (GSS) (P<0.0001) gene expression levels. Age influenced the expression of the thioredoxin (Trx) (P=0.0090), superoxide dismutase (SOD) (P=0.0194), glutathione reductase (GSR) (P<0.0001) and glutathione peroxidase 7 (GPx7) (P<0.0001) genes; we observed greater expression in birds at 21 days than at 42 days. Forty-two-day-old HS birds showed the highest H2O2 production (222.31 pmol dichlorofluorescein produced/min×mg mitochondrial protein). We also verified the effects of age and environment on the liver content of Glutathione (GSH) (P<0.0001 and P=0.0039, respectively) and catalase (CAT) enzyme activity (P=0.0007 and P=0.0004, respectively). Higher GSH content and lower CAT activity were observed in animals from the thermoneutral environment compared with the HS environment and in animals at 21 days compared with 42 days. Broilers at 42 days of age had higher plasma creatinine content (0.05 v. 0.01 mg/dl) and higher aspartate aminotransferase activity (546.50 v. 230.67 U/l) than chickens at 21 days of age. Our results suggest that under HS conditions, in which there is higher H2O2 production, 21-day-old broilers have greater antioxidant capacity than 42-day-old animals. [ABSTRACT FROM PUBLISHER]

1. A study was conducted to test the hypothesis that feed efficiency (FE) correlated with the expression of genes from the somatotropic axis and mitochondrial genes involved in energy production, and that the environment to which the birds are exposed influenced the expression of such genes. 2. Quails were divided into High-FE and low-FE groups and maintained in a comfortable or heat stress (HS) (38°C for 24 h) environment to evaluate changes in insulin-like growth factor I (IGF-I), growth hormone receptor (GHR), adenine nucleotide translocator (ANT), uncoupling protein (UCP) and cytochrome oxidase subunit III (COX III) messenger ribonucleic acid (mRNA) expression in liver and muscle tissues. 3. High-FE quails (0.28 g/g) presented a higher final body weight, greater weight gain and a better feed conversion ratio than low-FE birds (0.18 g/g). High-FE birds showed greater IGF-I mRNA expression in the liver and muscle and greater GHR mRNA expression in the muscle. 4. Environmental effects only affected GHR expression in the liver, with quails under comfortable conditions exhibiting greater GHR expression than quails subjected to HS. 5. There was a significant interaction between FE and environmental temperature on ANT mRNA expression in the liver. The greatest ANT mRNA expression was observed for high FE-birds that remained under comfortable conditions. 6. In the liver, UCP mRNA expression did not differ among the quails and was not affected by environment or efficiency. However, comparisons of the low- and high-FE birds revealed higher levels of UCP mRNA in the muscle of low-FE birds. 7. COX III mRNA expression in the liver was dependent on environmental temperature and FE. Higher COX III mRNA expression was observed in animals that remained under comfortable conditions, and high-FE birds exhibited higher expression levels compared to low-FE birds. 8. These results suggest a correlation between IGF-I, GHR, ANT, Í/CP and COX III gene expression and FE and that environmental temperature could affect the expression of some of these genes. [ABSTRACT FROM AUTHOR]

The aims of the present study were to evaluate the possible effects of heat stress (HS) on H202 production and to evaluate whether methionine supple-mentation (MS) could mitigate the deleterious effects on cell metabolism and the redox state induced by oxi-dative stress. Meat quails (Coturnix coturnix coturnix) were fed a diet that either met the nutritional demands for methionine or did not meet this demand (methio-nine 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 H207 pro-duction 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 ani-mals 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 inter-action 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 H702 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 pres-ent in higher levels in animals that were subjected to HS and fed the MS diet. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the effect of temperature and different levels of available phosphorus (aP) on the expression of nine genes encoding electron transport chain proteins in the Longissimus dorsi (LD) muscle of pigs. Two trials were carried out using 48 high-lean growth pigs from two different growth phases: from 15 to 30 kg (phase 1) and from 30 to 60 kg (phase 2). Pigs from growth phase 1 were fed with three different levels of dietary aP (0.107%, 0.321% or 0.535%) and submitted either to a thermoneutral (24°C and RH at 76%) or to a heat stress (34°C and RH at 70%) environment. Pigs from growth phase 2 were fed with three different levels of dietary aP (0.116%, 0.306% or 0.496%) and submitted either to a thermoneutral (22ºC and RH at 77%) or to a heat stress (32ºC and RH at 73%) environment. Heat stress decreased (P<0.001) average daily feed intake at both growth phases. At 24°C, pigs in phase 1 fed the 0.321% aP diet had greater average daily gain and feed conversion (P<0.05) than those fed the 0.107% or 0.535% while, at 34°C pigs fed the 0.535% aP had the best performance (P<0.05). Pigs from phase 2 fed the 0.306% aP had best performance in both thermal environments. Gene expression profile was analyzed by quantitative real-time polymerase chain reaction. Irrespective of growing phase, the expression of six genes was lower (P<0.05) at high temperature than at thermoneutrality. The lower expression of these genes under high temperatures evidences the effects of heat stress by decreasing oxidative metabolism, through adaptive physiological mechanisms in order to reduce heat production. In pigs from phase 1, six genes were differentially expressed across aP levels (P<0.05) in the thermoneutral and one gene in the heat stress. In pigs from phase 2, two genes were differentially expressed across aP levels (P<0.05) in both thermal environments. These data revealed strong evidence that phosphorus and thermal environments are key factors to regulate oxidative phosphorylation with direct implications on animal performance. [ABSTRACT FROM PUBLISHER]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The study aimed to evaluate the effects of citric acid supplementation on the performance and the gene expression in the duodenum of Japanese quail. Genes related to antioxidant activity: superoxide dismutase (SOD) and glutathione peroxidase 7 (GPX7); and genes related to nutrient uptake in the enterocytes’ apical membrane: sodium-glucose cotransporter 1 (SGLT1, responsible for the glucose absorption), glucose transporter 2 (GLUT2) and B0AT1 (responsible for the absorption of neutral amino acids in brush board membrane) were evaluated. For this, 270 laying quails (Coturnix japonica) were fed a diet supplemented with 0%, 0.6% or 1.2% of citric acid. Gene expression was evaluated by the quantitative reverse transcription-polymerase chain reaction (qRT-PCR) at 35 days old (n = 5). The highest expression of the SGLT1 gene was observed in quails fed the 1.2% citric acid supplemented diet (0.120 AU). Birds fed diets with both levels of citric acid supplementation showed a higher B0AT1 gene expression than quails fed no citric acid. Quails fed the 1.2% of citric acid supplemented diet had the lowest SOD gene expression (0.3455 AU). The birds receiving the diets supplemented with citric acid showed a lower GPX7 gene expression than the quails fed the 0% citric acid diet. These results suggests that the effect of citric acid on gene expression in the digestive tract may have contributed to the greater weight gain and lower feed intake observed in birds fed diets supplemented with citric acid. [ABSTRACT FROM AUTHOR]

The effects of supplying diets with flaxseed oil and a propolis-based product, with or without vitamin E, on dry matter intake, ruminal and total digestibility, ruminal parameters, biohydrogenation, and bacterial and protozoal populations in dairy cows were evaluated. Four Holstein cows, with a mean weight of 584 ± 52 kg and 90 ± 39 days in milk, were randomly assigned to a 4 × 4 Latin square. Diets were composed of 600 g/kg of dry matter (DM) as roughage and 400 g/kg of concentrate for the following diets: control diet; diet with 25 g flaxseed oil/kg DM (FO); diet with flaxseed oil, 1.2 g propolis-based product/kg DM (PBP); diet with flaxseed oil, PBP, and 375 IU vitamin E/kg DM. The flaxseed oil diet tended to reduce populations of Entodinium and total protozoa (P = 0.09) and significantly increased Butyrivibrio fibrisolvens (P = 0.008) count. However, Anaerovibrio lipolytica (P < 0.001) and Methanobrevibacter ruminantium counts (P = 0.013) were significantly reduced with the flaxseed oil diet. The PBP diet, with or without vitamin E, tended to enhance Butyrivibrio fibrisolvens (P = 0.09) count. The flaxseed oil diet tended to decrease the intake of organic matter (P = 0.09) and total carbohydrates (P = 0.05). Ruminal and total digestibility of crude protein and ether extract were higher with flaxseed oil. The PBP did not influence omasal nutrient flow, digestibility, short-chain fatty acid concentrations, pH, and ammonia in the rumen. Flaxseed oil addition in diets significantly increased (P < 0.05) the production of fatty acid (FA) cis 3-18:3 and CLA cis 9, trans 11-18:2 in milk, and tended (P < 0.10) to increase FA 18:0 and cis 9-18:1. PBP in diet significantly increased (P < 0.05) the production of CLA cis 9, trans 11-18:2 in milk. Among the ingredients added to the diets, flaxseed oil had the greatest effect on the parameters evaluated, and both PBP and PBP-E diets did not interfere with flaxseed oil activity in the rumen. [ABSTRACT FROM AUTHOR]

This study assessed the effects of combined supplementation with canthaxanthin (Cx) and 25-hydroxycholecalciferol (25-OH-D 3) 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 D 3 or the basal diet supplemented with 3 ppm Cx and 34.5 µg 25-OH-D 3 , 6 ppm Cx, and 69 µg 25-OH-D 3 , 9 ppm Cx and 103.5 µg 25-OH-D 3 , or 12 ppm Cx and 138 µg 25-OH-D 3. 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-D 3 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-D 3 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. [ABSTRACT FROM AUTHOR]