Effect of dietary inclusion of atorvastatin, garlic, and dill on growth performance, antioxidant defense, gut, and cardio-pulmonary function, and lipogenesis in broiler chickens.

In the present study, we evaluated the antihyperlipidemic and antioxidant effects of garlic and dill in comparison with atorvastatin to combat lipogenesis in broiler chickens. A total of 400 1-day-old chicks (Ross 308 strain) were randomly distributed into four experimental diets. Dietary treatments included a control diet, the control diet plus atorvastatin at 20 mg/kg, the control diet plus garlic dry powder (GDP) at 7.5 g/kg, and the control diet plus dill dry powder (DDP) at 7.5 g/kg. Chicks were maintained on experimental diets for 42 days under the recommended environmental conditions set out by the strain management manual. The results showed that weight gain, feed conversion ratio (FCR), and duodenal, jejunal, and ileal dimensions of villi (height, width, and the surface absorptive area) were improved by in-feed atorvastatin, GDP, or DDP when compared to the control (P < 0.05). The inclusion of atorvastatin or phytobiotic products increased circulatory levels of nitric oxide (NO) but decreased circulatory levels of malondialdehyde (MDA), triacylglycerol (TAG), and low-density lipoproteins cholesterol (LDL), with concomitant reductions in the T, R, and S waves amplitudes in the Lead 2 electrocardiogram (ECG) (P < 0.05). Dietary supplements caused an up-regulation of inducible nitric oxide synthase (iNOS), superoxide dismutase 1 (SOD1), and glutathione peroxidase (GPX) but reduced the expression of key hepatic lipogenic enzymes (fatty acid synthase (FAS) and hydroxy-methylglutaryl-CoA reductase (HMGCR) (P < 0.05). In conclusion, feed supplementation with atorvastatin, GDP, or DDP suppressed lipogenesis, enhanced antioxidant response, and improved gut and cardio-pulmonary function in broiler chicks subjected to hypobaric hypoxia.

Managing broiler production challenges at high altitude.

This review covers the challenges of broiler chickens at high altitude, with the focus on growth performance and physiological response. The review also sheds light on nutritional and management interventions that help overcome the challenges raised at high altitude. Reduced concentration of atmospheric oxygen is by far the biggest challenge that remarkably affect growth performance and livability of broiler chickens reared in high altitude area. Broiler chickens have endured intensive genetic selection, which potentially predispose them to several metabolic disorders. Hypoxia is an overriding factor that may increase the incidence of metabolic disorders, mainly ascites syndrome at high altitude. Commercial broiler strains cannot fully achieve their genetic potential when raising at highland regions. Careful nutrition and management considerations are required to prevent metabolic disorders when raising broilers at high altitude. In ovo or in-feed nutraceuticals such as l-carnitine and guanidinoacetic acid as well as pharmaceuticals, texture of feed and the use of proper sources and levels of dietary energy and protein are important factors that need to be carefully considered for rearing broiler chickens at high altitude. Management strategies such as lighting programs have been shown to be effective to circumvent ascites prevalence. Special breeding programs may also be considered to develop strains with resistance to ascites.

Pomegranate peel as a phytogenic in broiler chickens: Influence upon antioxidant, lipogenesis and hypotensive response.

The aim of this study was to evaluate antioxidant, antihyperlipidemic and hypotensive properties of pomegranate peel (PP) on antioxidant status, fat deposition, lipid peroxidation and pulmonary hypertensive response in broiler chickens. A total of 375 one-day-old male broilers (Cobb 500) were randomly assigned to five treatments included dietary PP levels of 0, 2.5, 5.0, 7.5 and 10 g/kg. Supplementation of PP at 7.5 and 10 g/kg resulted in significant upregulation of hepatic catalase (p < 0.004) and superoxide dismutase1 (SOD1; p < 0.05), which reflected in decreased concentration of circulatory malondialdehyde (MDA). Dietary inclusion of PP at 7.5 and 1.0 g/kg significantly decreased serum concentrations of triglycerides (p < 0.004) and cholesterol (p < 0.006) with concomitant decrease in abdominal fat deposition (p < 0.05). The antihyperlipidemic effect of PP was mediated through down-regulation of peroxisome proliferator activated receptor alpha (PPARα). Hypotensive effect of PP was also observed at 7.5 and 10 g/kg as reduced heart weight and the right-to-total ventricular weight ratio (RV/TV) and decreased mortality from pulmonary hypertension. The hypotensive property of PP was associated with increased concentration of serum nitric oxide. In conclusion, this study revealed antioxidative, antihyperlipidemic and hypotensive effects of PP at 7.5 and 10 g/kg in broiler chickens exposed to hypobaric hypoxia. Health-beneficial effects of PP suggest this product as a promising multi-functional phytogenic feed additive for broiler chickens.

Effect of dietary supplementation of whey powder and Bacillus subtilis on growth performance, gut and hepatic function, and muscle antioxidant capacity of Japanese quail.

This experiment was conducted to evaluate the effects of dietary supplementation of whey powder (WP), Bacillus subtilis (BAS), and their combination (MIX) on growth performance, intestinal morphology, caecal microflora, hepatic gene expression, blood metabolites, and skeletal muscle antioxidant capacity in Japanese quails. A total of 400 one-day-old Japanese quails were randomly distributed to 20-floor pens (4 dietary treatments, 5 replications per treatment, 20 birds per pen). The birds were fed a basal diet (control, CON) or the basal diet supplemented with 40 g/kg WP, 1 g/kg BAS probiotic or 40 g/kg WP plus 1 g/kg BAS probiotic for five weeks. Feed intake was not affected by the treatments at any stage of the trial. However, the WP, BAS, and MIX feed had better weight gain and feed conversion ratio compared to the CON during the entire production period (day 1-35; p < .05). Feeding the WP, BAS, and MIX diets caused no significant difference in morphometric measures in the duodenum, jejunum, and ileum other than the villus height to crypt depth ratio in the ileum (p < .05). The expression of insulin-like growth factor-1 (IGF-1) and growth hormone genes was highly upregulated in the liver of the birds fed the MIX diet (p < .05). Feeding birds with the diets containing WP, BAS, and MIX increased the population of caecal lactic acid bacteria and reduced serum cholesterol concentration compared to the CON diet (p < .05). Likewise, the tested feed additives increased superoxide dismutase and glutathione peroxidase enzyme activities in the thigh muscle (p < .05). No synergistic effect was found between WP and BAS in studied parameters other than IGF-1 gene expression. Improved growth performance of Japanese quails by feeding the WP, BAS, and the MIX feed could be linked to improved absorptive capacity of the small intestine as well as over-expression of anabolic growth factors. In conclusion, WP with or without BAS could be considered as a beneficial dietary supplement to enhance productive performance, gut functionality, and antioxidant capacity of Japanese quail.

Expression of antioxidant genes in broiler chickens fed nettle (Urtica dioica) and its link with pulmonary hypertension.

Nettle (Urtica dioica) contains a wide range of chemical constituents that confer a strong antioxidant capacity to the plant. The present study was to investigate the antioxidant gene expression and pulmonary hypertensive responses of broiler chickens to U. dioica. A total of 240 one-d-old broilers (Ross 308) were randomly assigned to 4 dietary levels of U. dioica (0, 0.5%, 1% and 1.5%). Birds were reared for 6 wk in a high altitude region (2,100 m). The results showed a significant relative overexpression (target gene/ß-actin as the arbitrary unit) of catalase (CAT) and superoxide dismutase 1 (SOD1) in the liver and lung of the chickens fed U. dioica. Lipid peroxidation was significantly suppressed, as reflected in reduced circulatory concentrations of malondialdehyde (MDA) in the birds fed U. dioica. These birds also had significantly (P < 0.05) higher serum nitric oxide (NO) concentrations than those in the control group. Feeding U. dioica at 1% and 1.5% also attenuated the right ventricular hypertrophy (reflected in the lower right to total ventricular weight ratio), which was associated with a significant lower rate of mortality from pulmonary hypertension syndrome. Feeding U. dioica led to an upregulation of hepatic and pulmonary antioxidant genes.

Combined effects of guanidinoacetic acid, coenzyme Q10 and taurine on growth performance, gene expression and ascites mortality in broiler chickens.

High levels of guanidinoacetate acid (GAA) deteriorate growth response in broiler chickens. We propose using coenzyme Q10 , an antioxidant, and taurine (TAU), a methyl donor, to cope with the situation when high level of GAA included in diet. GAA was supplemented at 0 (control), 0.75, 1.5 and 2.25 g/kg in isoenergetic and isonitrogenous diets and fed to broilers (Cobb 500) from 1 to 40 days post-hatch. Three additional diets were prepared by adding CoQ10 (40 mg/kg), TAU (40 mg/kg) or their combination (both CoQ10 and TAU at 40 mg/kg) to the 2.25 g/kg GAA group. The experimental design used was a completely randomized design. While weight gain (p = 0.038) and feed conversion ratio (p = 0.024) improved when GAA added at 1.5 g/kg, higher supplementation (2.25 g/kg) deteriorated these responses. These responses, however, were significantly restored by using CoQ10 , TAU or their combination. Abdominal fat deposition was significantly decreased when TAU added to broiler diets by virtue of upregulating peroxisome proliferator-activated receptor alpha. Supplementing broiler diets with CoQ10 and TAU or their combination significantly decrease ascites mortality. In conclusion, CoQ10 and TAU have shown beneficial effects when high level of GAA included in broiler diets.

Evaluation of hepatic lipogenesis and antioxidant status of broiler chickens fed mountain celery.

BACKGROUND: Fatness is an unwanted side effect of genetic selection in broiler chickens. In this study, we introduce mountain celery powder as a feed supplement to suppress lipogenesis and improve antioxidant status in broiler chickens. Male broiler chicks (Ross 308) were fed a control diet or a diet that includes mountain celery (MC) at 7.5 gkg-1over 42 days. RESULTS: Body weight gain and feed conversion ratio significantly (P < 0.05) improved in chicks fed MC. A highly significant down-regulation of genes involved in hepatic lipogenesis including acetyl CoA carboxylase (ACC), fatty acid synthase (FAS), malic enzyme (ME), and lipoprotein lipase (LPL) was observed in the liver of chickens fed MC. These birds, however, had greater compensatory upregulation in antioxidative genes SOD1 and catalase in the liver compared to the birds that received the control diet. Birds received MC had significantly lower level of lipid peroxidation (1.59 µmol/L serum malondialdehyde) compared to birds from the control group (3.57 µmol/L; P = 0.0024). Birds fed MC had significantly (P < 0.05) lower circulatory concentrations of triacylglycerols, cholesterol, and LDL but higher concentrations of HDL. Relative liver weight and abdominal fat deposition were significantly reduced by feeding MC. CONCLUSIONS: It can be concluded that feeding birds MC significantly suppresses hepatic lipogenesis by down-regulating key hepatic lipogenic enzyme genes and boosts antioxidant capacity by up-regulating hepatic antioxidantive genes.

Pulmonary hypertensive response of broiler chickens to arginine and guanidinoacetic acid under high-altitude hypoxia.

This study assessed the preventive effects of arginine (ARG) and guanidinoacetic acid (GAA) on the incidence of pulmonary hypertension syndrome (PHS) in broiler chickens. Four isoenergetic and isonitrogenous diets were prepared, including: (i) the control, (ii) the control supplemented with 1 g/kg ARG, (iii) the control supplemented with 1 g/kg GAA, and (iv) the control supplemented with 1.5 g/kg GAA. These diets were fed to broilers (Ross 308) from day 1 to 42 post-hatch. Criteria evaluated in the experiment were growth performance, carcass characteristics, serum and blood variables, lead-II electrocardiogram, and ET-1 and iNOS gene expression in heart and lungs. Mortality from PHS was recorded daily. The results showed that ARG and GAA supplements improved the feed conversion ratio (FCR) compared to the control (P < 0.05). Supplementation of ARG and GAA significantly (P < 0.05) increased serum nitric oxide (NO) concentration. ARG and GAA supplementation significantly reduced the haematocrit value and the heterophil to lymphocyte ratio in the blood. A significant (P < 0.05) decline in S-wave amplitude of the lead-II electrocardiogram, right to total ventricular weight ratio (RV:TV) and ascites mortality was observed by supplementing ARG or 1.5 g/kg GAA. Addition of ARG and GAA supplements did not significantly change ET-1 and iNOS gene expression in the heart and lung relative to the control. In conclusion, GAA supplementation at 1.5 g/kg had a potential to improve growth performance and could prevent PHS.

Growth Performance and Right Ventricular Hypertrophy Responses of Broiler Chickens to Guanidinoacetic Acid Supplementation under Hypobaric Hypoxia.

Guanidinoacetic acid (GAA) has been shown to spare arginine (ARG) requirements in chickens. ARG plays a critical role in enhancing growth and preventing right ventricular hypertrophy (RVH) in broiler chickens subjected to hypobaric hypoxia. However, ARG is not available as a feed grade supplement in the market. Therefore, we evaluated the effects of commercially available GAA supplement as an alternative on growth performance and RVH in broilers raised at high altitude (2100 m). Five graded levels of GAA ranging from 0 (control) to 2 g/kg were provided in isoenergetic and isonitrogenous diets to broilers (Ross 308) from day 1 to 42, post-hatch. Results indicated that responses to GAA were nonlinear and attained plateau values within the studied range of GAA supply. While weight gain and feed intake were unaffected by GAA supply, feed conversion ratio was improved by GAA supplementation up to 1.5 g/kg. Similar trends were observed for the proportions in the liver and heart, as well as hematocrit. GAA supplementation at 1 and 1.5 g/kg resulted in reduced abdominal fat deposition as well as a decline in right-tototal ventricular weight ratio (RV:TV, an index of RVH). A significant (P<0.05) increase in serum nitric oxide concentration was observed at 1 and 1.5 g/kg GAA supplementation. However, GAA supply led to lower serum malondialdehyde and uric acid levels than in the control. In conclusion, GAA supplementation up to 1.5 g/kg had the potential to improve growth performance and RVH response. Meanwhile, GAA supply beyond 1.5 g/kg could deteriorate these responses.

Hybridization increases mitochondrial production of reactive oxygen species in sunfish.

Mitochondrial dysfunction and oxidative stress have been suggested to be possible mechanisms underlying hybrid breakdown, as a result of mito-nuclear incompatibilities in respiratory complexes of the electron transport system. However, it remains unclear whether hybridization increases the production of reactive oxygen species (ROS) by mitochondria. We used high-resolution respirometry and fluorometry on isolated liver mitochondria to examine mitochondrial physiology and ROS emission in naturally occurring hybrids of pumpkinseed (Lepomis gibbosus) and bluegill (L. macrochirus). ROS emission was greater in hybrids than in both parent species when respiration was supported by complex I (but not complex II) substrates, and was associated with increases in lipid peroxidation. However, respiratory capacities for oxidative phosphorylation, phosphorylation efficiency, and O2  kinetics in hybrids were intermediate between those in parental species. Flux control ratios of capacities for electron transport (measured in uncoupled mitochondria) relative to oxidative phosphorylation suggested that the limiting influence of the phosphorylation system is reduced in hybrids. This likely helped offset impairments in electron transport capacity and complex III activity, but contributed to augmenting ROS production. Therefore, hybridization can increase mitochondrial ROS production, in support of previous suggestions that mitochondrial dysfunction can induce oxidative stress and thus contribute to hybrid breakdown.

Interspecific and environment-induced variation in hypoxia tolerance in sunfish.

Hypoxia tolerance is a plastic trait, and can vary between species. We compared hypoxia tolerance (hypoxic loss of equilibrium, LOE, and critical O2 tension, Pcrit) and traits that dictate O2 transport and metabolism in pumpkinseed (Lepomis gibbosus), bluegill (L. macrochirus), and the naturally occurring hybrid in different acclimation environments (wild versus lab-acclimated fish) and at different temperatures. Wild fish generally had lower Pcrit and lower PO2 at LOE in progressive hypoxia than lab-acclimated fish, but time to LOE in sustained hypoxia (PO2 of 2kPa) did not vary between environments. Wild fish also had greater gill surface area and higher haematocrit, suggesting that increased O2 transport capacity underlies the environmental variation in Pcrit. Metabolic (lactate dehydrogenase, LDH; pyruvate kinase, PK; citrate synthase; cytochrome c oxidase) and antioxidant (catalase and superoxide dismutase) enzyme activities varied appreciably between environments. Wild fish had higher protein contents across tissues and higher activities of LDH in heart, PK in brain, and catalase in brain, liver, and skeletal muscle. Otherwise, wild fish had lower activities for most enzymes. Warming temperature from 15 to 25°C increased O2 consumption rate, Pcrit, PO2 at LOE, and haemoglobin-O2 affinity, and decreased time to LOE, but pumpkinseed had ≥2-fold longer time to LOE than bluegill and hybrids across this temperature range. This was associated with higher LDH activities in the heart and muscle, and lower or similar antioxidant enzyme activities in several tissues. However, the greater hypoxia tolerance of pumpkinseed collapsed at 28°C, demonstrating that the interactive effects of hypoxia and warming temperature can differ between species. Overall, distinct mechanisms appear to underpin interspecific and environment-induced variation in hypoxia tolerance in sunfish.

Kelussia odoratissima Mozzaf - a promising medicinal herb to prevent pulmonary hypertension in broiler chickens reared at high altitude.

ETHNOPHARMACOLOGICAL RELEVANCE: Kelussia odoratissima Mozzaf, formerly Apium odoratissima, is a plant locally called "Karafs", found in central Zagros region of Iran. Leaves and stems of the plant are traditionally used in the treatment of hypertension and inflammation. Lowering blood pressure effects of Kelussia odoratissima Mozzaf (wild celery) was evaluated in preventing pulmonary hypertension syndrome (PHS) in broiler chickens reared at high altitude (2,100 m). MATERIALS AND METHODS: A total number of 208 day-old male broilers (Ross 308) were randomly assigned to four treatments including different levels of Kelussia odoratissima Mozzaf (0%, 0.25%, 0.5%, and 0.75%) in a 42-day trial. RESULTS: Body weight gain and feed:gain responses significantly (P<0.05) improved when Kelussia odoratissima Mozzaf was included in broiler diets at 0.75% in the growing stage and throughout the trial. Over-expression of inducible nitric oxide (NO) synthase in the heart was observed in chickens fed Kelussia odoratissima Mozzaf. Birds received Kelussia odoratissima Mozzaf at 0.5% and 0.75% had significantly (P<0.05) higher circulatory concentrations of NO though significantly (P<0.05) lower serum malondialdehyde concentration, hematocrit and heterophil to lymphocyte ratio when compared to the birds fed the control diet. Feeding Kelussia odoratissima Mozzaf at 0.5% and 0.75% prevented from right ventricular hypertrophy and led to a significant decline in mortality from PHS. CONCLUSION: It can be concluded that Kelussia odoratissima Mozzaf is a promising medicinal herb to prevent PHS in broiler chickens by improving blood pressure and antioxidant responses.

L-carnitine supplementation decreases lipid peroxidation and improves cardiopulmonary function in broiler chickens reared at high altitude.

An experiment was carried out to examine the effects of L-carnitine supplementation on growth performance and cardiopulmonary function of broiler chickens reared at high altitude (2100 m above sea level). A total of 96 day-old male chicks (Cobb 500) were randomly assigned into two dietary treatments containing 0 (control group) and 200 mg/kg L-carnitine. The experimental diets were fed for a period of 42 days consisting of the starting (days 1 to 21) and growing periods (days 21 to 42). Nutrient requirements of chickens met the NRC (1994) recommendations. The results showed that dietary L-carnitine had no significant influence on body weight gain, feed intake and feed conversion ratio. L-carnitine reduced plasma concentration of malondialdehyde, packed cell volume (PCV) and abdominal fat deposition compared to the control (P < 0.05). A significant (P < 0.05) decrease was observed in the right to total ventricular weight ratio (RV:TV) in birds receiving L-carnitine when compared to the control. Supplementation of L-carnitine increased plasma nitric oxide and immune responsiveness, which manifested in an increased toe-web thickness index measured at 24 h following the injection of phytohaemagglutinin P. In conclusion, supplementation of L-carnitine had beneficial effects on preventing lipid peroxidation and pulmonary hypertension in broiler chickens raised at high altitude.

An L-Arginine supplement improves broiler hypertensive response and gut function in broiler chickens reared at high altitude.

An experiment was carried out to examine the effects of supplemental dietary arginine (ARG) on growth, hypertensive response, and gut function in broilers reared at high altitude (2,100 m). A total of 120 day-old male broilers (Cobb 500) were divided equally into two treatment groups. Treatments included a control basal diet composed of corn and soybean meal and an experimental diet to which an L-ARG supplement was added at 10 g/kg. The trial lasted for 42 days. There were no treatment differences with regard to feed intake, body weight gain, or feed conversion ratio. However ARG supplementation did increase the plasma concentration of nitric oxide, a potent vasodilator (P<0.05), and attenuated indices of pulmonary hypertension as reflected by reductions in the hematocrit and the right to total ventricular weight ratio (P<0.05). Significantly enhanced intestinal mucosal development was observed in broilers receiving ARG supplement when compared with controls (P<0.05), suggesting that ARG supplementation increased the absorptive surface area of the jejunum and ileum. In conclusion, broiler diets supplemented with ARG beneficially improved pulmonary hemodynamics and appeared to enhance gut function.

Plexiform lesions in the lungs of domestic fowl selected for susceptibility to pulmonary arterial hypertension: incidence and histology.

Plexiform lesions develop in the pulmonary arteries of humans suffering from idiopathic pulmonary arterial hypertension (IPAH). Plexogenic arteriopathy rarely develops in existing animal models of IPAH. In this study, plexiform lesions developed in the lungs of rapidly growing meat-type chickens (broiler chickens) that had been genetically selected for susceptibility to IPAH. Plexiform lesions developed spontaneously in: 42% of females and 40% of males; 35% of right lungs, and 45% of left lungs; and, at 8, 12, 16, 20, 24, and 52 weeks of age the plexiform lesion incidences averaged 52%, 50%, 51%, 40%, 36%, and 22%, respectively. Plexiform lesions formed distal to branch points in muscular interparabronchial pulmonary arteries exhibiting intimal proliferation. Perivascular mononuclear cell infiltrates consistently surrounded the affected arteries. Proliferating intimal cells fully or partially occluded the arterial lumen adjacent to plexiform lesions. Broilers reared in clean stainless steel cages exhibited a 50% lesion incidence that did not differ from the 64% incidence in flock mates grown on dusty floor litter. Microparticles (30 µm diameter) were injected to determine if physical occlusion and focal inflammation within distal pulmonary arteries might initiate plexiform lesion development. Three months postinjection no plexiform lesions were observed in the vicinity of persisting microparticles. Broiler chickens selected for innate susceptibility to IPAH represent a new animal model for investigating the mechanisms responsible for spontaneous plexogenic arteriopathy.

Blood gas values and pulmonary hypertension as affected by dietary sodium source in broiler chickens reared at cool temperature in a high-altitude area.

One hundred and twenty day-old male chicks (Ross 308) reared at a cool temperature at high altitude were subjected to the following two treatments in a completely randomised design: (1) a group for which the sodium requirements were supplied by sodium chloride from day-old age and regarded as control, (2) a group similar to the control but for which 50% of the sodium requirements was supplied by sodium bicarbonate from day-old age. Provision of sodium equally from NaCl and NaHCO3 significantly (P < 0.05) increased the partial pressure of oxygen and the saturation of haemoglobin with oxygen, and significantly (P < 0.05) decreased the heterophil to lymphocyte ratio. The right ventricle to total ventricles ratio shifted to lower values as a result of substituting NaHCO3 for NaCl as a sodium source. Growth performance and carcass characteristics were not affected significantly by the dietary sodium source.