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Objective: This study aimed to assess the association between vitamin D and sleep health and to investigate whether depression could mediate this relationship. Methods: A cross-sectional analysis was performed using the 2005–2014 US National Health and Nutrition Examination Survey (NHANES) data. The logistic regression models were conducted to evaluate association of serum vitamin D concentrations with sleep health and depression. Mediation analyses were conducted to investigate the mediated effects of depression on the association of vitamin D with sleep health. Results: In multivariate logistic models, vitamin D was found to be negatively associated with an increased risk of poor sleep health, with an odds ratio (OR) of vitamin D deficiency versus sufficiency was 1.256 (95% CI = 1.084–1.455). Additionally, univariate logistic models showed that vitamin D was also negatively associated with depression risk (vitamin D deficiency vs. sufficiency: OR = 1.699, 95% CI = (1.373–2.103). Further mediation analyses showed that the association of vitamin D with sleep health was mediated by depression, with the mediating effects of depression accounted for 44.56% of the total effects. Conclusion: Vitamin D affects sleep health directly and indirectly through depression. The results suggest that interventions increasing intake of vitamin D should be prioritized to promote sleep health of persons with or at risk of depression. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effects of dietary zinc (Zn) supplementation on performance, immune responses and gastrointestinal tract features of broilers fed wheat-soybean meal diet. In addition, optimised dietary Zn level was estimated based on dose-response data. A total of 500 one-day-old male Ross-308 broiler chicks were randomly assigned to 10 dietary treatments with five replicates and ten birds per replicate in a 5 × 2 factorial arrangement of five graded (+40 mg/kg) dietary Zn levels with or without phytase (500 FTU/kg of diet) supplementation. By increasing dietary Zn concentration, final live body weight (LBW), daily weight gain (WG), feed intake (FI), and European Production Efficiency Factor (EPEF), antibody titres against the sheep red blood cell inoculation, cutaneous basophils hypersensitivity to PHA-P injection, jejunum villus height, and apparent dry matter digestibility (ADMD) increased with a significant linear trend. Phytase supplementation improved WG and ADMD and decreased pancreas and intestine relative weights. The interaction effects of dietary Zn concentration and phytase supplementation on the whole of evaluated traits were not significant. Optimum dietary Zn levels were estimated by the regression models at 70, 82, 98, and 110 mg/kg of diet for optimised EPEF and immunity, LBW and WG, appetites, and ADMD, respectively. It is concluded, in the broiler chickens fed wheat-soybean meal diet, Zn and phytase supplementation can improve growth performance, immune response, digestibility, and intestinal features. The Zn requirement is higher than the NRC (1994) recommendation. The efficacy of dietary Zn was not affected by dietary phytase supplementation. In the broilers fed wheat-soy diet: •Dietary Zn and phytase supplementation improve growth performance. •The Zn requirement is higher than the NRC recommendation. [ABSTRACT FROM AUTHOR]

Increased blood lactic acid is likely to be involved in the incidence of sudden death syndrome (SDS) in broiler chicken. Guanidinoacetic acid (GAA) with direct or indirect influence on the cardiovascular system may provide, to some degree, protection against lactic acidemia in birds. A total number of 144 male broiler chicks (Ross 308) were used in a complete randomised block design to investigate the effects of dietary supplementation of GAA at 0.6, 1.2, 1.8, 2.4 and 3 g/kg on the physiological response of broiler chicks to an acute lactic acidosis in an 8-days experiment. Birds receiving 1.8 and 3 g/kg GAA exhibited lesser mortality percentage compared with the control birds and those received dietary GAA at 0.6 and 1.2 g/kg (p <.03). Dietary inclusion of 1.2 g/kg GAA to broiler chicks increased serum concentration of uric acid compared to the control birds and those received 2.4 g/kg (p <.02). The mean serum concentration of creatinine was greater in the birds receiving different GAA levels compared with the control birds (p <.0001). The serum concentration of nitric oxide decreased in the birds receiving 1.2 g/kg GAA by 21.05 and 15.57% compared with the control birds and those received 1.8 g/kg of GAA, respectively (p <.04). A lesser frequency for liver colour score 5 was observed in the birds fed on the diet with 0.6 g/k GAA (p <.0001). It was concluded that dietary administration of GAA deteriorates the adaptive physiological responses to an acute lactic acidosis in broiler chicken possibly through liver and kidney dysfunction. Dietary guanidinoacetic acid decreased mortality but showed an adverse effect on growth performance in chickens exposed to acute lactic acidosis. The adverse effects of guanidinoacetic acid may happen through liver and kidney dysfunction. No firm evidence was found to suggest a significant effect of extra nutritional guanidinoacetic acid on the incidence of sudden death syndrome in chicken. [ABSTRACT FROM AUTHOR]

The aim of the present study was to evaluate the effects of dietary total sulphur amino acids (TSAA) levels and guanidinoacetic acid (GAA) supplementation on performance, carcase yield and energetic molecular metabolites in heart and breast muscle of broiler chickens fed wheat-soy diet. A total of 450, male one-day-old Ross-308 broiler chicks were assigned in a 3 × 3 factorial arrangement of nine treatments, five replicates and 10 birds each. Dietary treatments included three graded levels of supplementary TSAA (+0.4 g/kg per level) resulting in a deficient, adequate and plus level of recommended by strain, with three levels of GAA (0, 0.6 and 1.2 g/kg) and were fed for 35 days. Dietary TSAA levels only enhanced performance during the starter period (p <.05). At adequate TSAA level, weight gain (WG) and feed conversion ratio (FCR) in the grower phase were positively affected by supplementing GAA at 1.2 g/kg (p <.05). The FCR during the overall experimental period was significantly lower when feeding GAA at 0.6 and 1.2 g/kg compared to non-supplemented (p <.05). Heart and breast muscle ATP/AMP ratio and breast muscle ADP and PCr concentration and PCr/CrN ratio in the birds fed 1.2 g/kg GAA diet were significantly higher than non-supplemented (p <.05). It is concluded, effects of dietary GAA supplementation were influenced by dietary TSAA level, this indicates to need for proper dietary sulphur amino acid formulation by GAA supplementation. Dietary GAA supplementation could improve broiler chicken's growth performance via regulating some aspects of energy metabolism. Guanidinoacetic acid plays a critical role in energy homeostasis. The effect of dietary Guanidinoacetic acid supplementation may influenced by the dietary sulphur amino acids. [ABSTRACT FROM AUTHOR]

This work aimed to investigate the ions composition of wastewater produced after reverse osmosis and the suitability of using wastewater as a drinking source for different farm animals, especially in poultry, the most sensitive/intolerant farm animals. Ten samples of wastewater (three replicates) were obtained from different water filtration stations in Jordan and were analysed for their cations: sodium (Na), potassium (K) and calcium (Ca) and anions; fluorine (F), chlorine (Cl), nitrite (NO2), nitrate (NO3), phosphate (PO4) and sulfate (SO4) concentrations. The highest variation was found in both K (CV% = 99.7) and F (CV% = 90.78). With mineral concentration in extreme/highest cases, analysed wastewater samples can provide a negligible contribution to poultry (broilers) requirements, as the case in K (0.27%) or can supply excessive amounts as in Na (150.0%). In all wastewater samples, Cl and F levels were above the safety guidelines recommended for poultry drinking water. In some of the selected samples, presence of Na (9 out of 10 samples) and sulfate (5 out of 10 samples) was higher than the recommended limits for broilers. Other analysed minerals were found tolerable by poultry. Results suggest the feasibility of re-using wastewater directly or indirectly after mixing it with public water as a source of drinking water for farm animals. [ABSTRACT FROM AUTHOR]

Although commercial broiler feed is usually differently conditioned before pelleting, the nutritional consequences of fine grinding or expanding as pre-pelleting treatments are poorly defined so far. Therefore, the effects of these two pre-treatments on nutrient digestibility, broiler performance and digestive tract of broilers were tested. In order to investigate possible interactions between pre-treatments and diet composition two diets differing in rapeseed expeller proportion were tested in a two by two factorial design. Thus, four diets were designed including two diets containing 6% rapeseed expeller (RSE) which were pre-treated by fine grinding (6%FgP) or expanding (6%ExP), and two corresponding diets containing 12% RSE (12%FgP and 12%ExP). For the experiments, 864 male broilers were used. There was a significant diet-by-technical feed treatment (TFT) interaction in case of the digestibility of all considered crude nutrients (p < 0.05). Diet 6%ExP showed higher crude protein digestibility compared to other feeds (p < 0.001). The highest digestibility of organic matter, ether extract, crude fibre and N-free extractives achieved diet 12%FgP. Diets 6%ExP and 12%FgP showed higher N-corrected metabolisable energy content (p < 0.001). TFT affected daily feed intake (DFI) and body weight (BW) gain in a diet-dependent manner (p < 0.001). Feeding of 6%FgP enhanced DFI and BW gain compared to other feeds but 6%ExP reduced both parameters (p < 0.001). Weights of proventriculi and gizzards of animals fed 6%ExP were increased compared with 6%FgP (p < 0.01). In contrast, proventricular length in animals fed 6%FgP was increased compared with diet 6%ExP (p = 0.042). Moreover, animals fed 6%FgP had wider proventriculi than animals fed 12%FgP (p = 0.023). Feed 6%ExP increased proventricular weight compared to 12%ExP (p = 0.001). With regard to the strong relationships between diet and TFT no specific processing method can be recommended according to considered nutritional aspects. A marked prevention of proventricular dilatation due to pellet feeding could not be realised by various used TFT or feed formulations. Used amounts of RSE had no obvious adverse effects on considered nutritional aspects. [ABSTRACT FROM AUTHOR]

The yellow-feather broiler is a popular poultry breed in Asia, particularly in China. In this study, we performed RNA-seq analysis to identify differentially expressed genes (DEGs) in the heart of yellow-feather broilers that had been subjected to heat stress treatment (38 ± 1 °C for 8 h, over 7 d) and determine the response of the heart to high temperature and its effects on yellow-feather broiler physiology. We found that body weight (BW) of the heat stress treatment group (BW28 = 354.8 ± 34.8 g) was significantly decreased (p =.033) compared with that of the control group (BW28 = 384.8 ± 58.9 g). However, there was no significant reduction in the heart relative weight (HRW) (p =.538). A total of 37 DEGs related to energy metabolism responded to heat stress in the heart of yellow-feather broiler. The results of KEGG pathways analysis indicated that these genes are involved in oxidative phosphorylation (KO: 00190), cardiac muscle contraction (KO: 04260) and carbon metabolism (KO: 01200). Analysis of the cardiac transcriptome of yellow-feather broilers subjected to heat stress indicated that the heart of these birds has specific physiological mechanisms for regulating body growth in response to high-temperature environments. Yellow-feather broilers, a popular poultry breed in Asia, were used to determine how the heart responds to heat stress. A total of 37 genes in the heart of yellow-feather broilers showed differential expression in response to heat stress. The differentially expressed genes (DEGs) are associated with oxidative phosphorylation, cardiac muscle contraction and carbon metabolism pathways. [ABSTRACT FROM AUTHOR]

The effect of different feed withdrawal durations and re-feeding on broiler performance was investigated. A total of 225 broiler chicks (Ross 308) were assigned to 5 groups; control (full feeding) and feed withdrawal for 6, 8, 10 and 12 h daily. Feed intake and weight gain were reduced (P < .05) in the feed withdrawal groups during the starter phase, but were not affected during later growth. Feed conversion ratio was not affected by the treatment. The relative weight of carcass was reduced (P < .05) in 6 and 12 h feed withdrawal groups. Breast weight was lowest on the control group and highest on the 8 h withdrawal (P < .05) group. The weight of the thigh was reduced (P < .05) on the control group. Plasma protein was higher on the control group and 6 h group compared to 10 h feed withdrawal group (P < .05). Plasma albumin was reduced on 12 and uric acid on the control and 6 withdrawal groups. There were no treatment effects on plasma cholesterol, HDL and LDL values. E. coli count was not affected by treatment, but Lactobacilli count was higher (P < .05) on the 12 h feed withdrawal group. Young broilers subjected to feed withdrawal for 8-10 h daily can compensate for performance losses in the early stage of growth and maximize the relative weights of carcass, breast muscle and thigh, but withdrawal lengths of 6 and 12 h might be too short and too long, respectively, to improve performance losses after resumption of full feeding. [ABSTRACT FROM AUTHOR]

Ascites syndrome (AS) is a metabolic disorder in fast-growing broilers that is characterized by non-tumult fluid collection in the abdomen. The objective of this study was to evaluate the effects of variable feeding and rearing temperature on AS occurrence in broilers. A total of 360 one-day-old male Ross-308 chicks were assigned to three equal groups (n = 120) fed pellet, crumble or mash diets and within each group, half of birds (n = 60, starting from the 22nd day of age) were reared under two different temperatures: at 23°C (comfort) or at 14°C (cold), respectively. There were six treatments and four replicates including 15 broilers per replicate per treatment. Birds' growth performances and blood parameters as well the incidence of ascites were assessed. The haematocrit percentage, T3 and T4 hormones activity in pellet-fed group under cold temperature conditions were significantly higher (P < .05) than the other groups. Based on the results, the occurrence of AS under mash-fed regime was less than pellet and crumble dietary groups (P > .05). Further, feeding of mash diet reduced broilers' feed consumption per unit of time, especially by level of achieving energy that is reducing the growth and AS. [ABSTRACT FROM AUTHOR]

An in-depth investigation of an unusual, non-enclosed manure storage hydrogen sulfide-induced fatality on a Holstein beef production operation is presented. The case involved several factors that likely played a role in the young farmer’s death. These included zero wind movement, a reported temperature inversion in the area, relatively cool late summer outdoor temperatures on the morning of the incident, higher outdoor temperatures the week prior, and a high by-product steer ration containing ingredients that contributed significant sulfur content to the stored manure. Recommendations are offered for future research to determine the combinations of conditions and inputs that have potential to increase human and animal risk around manure storage structures. Based on this case and others recently documented showing unsafe levels of hydrogen sulfide being released from similar outdoor storages, it is critical that agricultural industry experts and input suppliers continue to analyze risk and consequences associated with new management practices, processes, inputs (including feed ingredients and animal bedding), machines, and other technology developed to support animal agriculture. Production practice and educational guidance are also offered based on this case and published literature. [ABSTRACT FROM AUTHOR]

The present study was carried out to investigate the effect of different levels of guanidine acetic acid (GAA) on the performance, carcase yield and energetic molecular metabolites of breast muscle in broiler chickens fed with wheat-soy diet containing different levels of nutrient densities. 450- day-old male broiler chicks (Ross 308), assigned in a completely randomised design experiment with factorial arrangement 3×3, 9 treatments and 5 replicates of 10 birds each. The diets included three levels of GAA supplementation (0, 0.6, 1.2 g/kg of diet) and three dietary nutrient density (ND) levels (low; 2800 kcal ME/kg, medium; 2950 kcal ME/kg and high; 3100 kcal ME/kg with constant rates of ME to other nutrients). The experimental diets were fed ad libitum from 1-42 days of age. One bird per pen was euthanized on day 10 and 42 to determine the energetic molecular metabolites concentrations of adenosine phosphate (ATP, ADP and AMP), phosphocreatine (PCr) and creatinine (CRN) in breast muscles. The inclusion of 0.6 g/kg GAA in wheat-soy diet, improved production performance, the relative weight of breast yield and increased the concentration of high phosphate energy metabolites (PCr, ATP/ADT and PCr/ATP) in breast muscle. The supplementation of high-density diet with GAA compared with the lowdensity diet improved broiler chicken's performance. It is concluded that the use of GAA in diet may facilitate the conversion of high-energy phosphates to form ATP in muscles and thus improve broiler chicken's performance. [ABSTRACT FROM AUTHOR]

The objective of this experiment was to evaluate the effect of bee glue (BG) on the performance, relative visceral weights, some blood parameters, and immune status of broilers. A total of 200 male Ross 308 broiler chicks were randomly assigned to 5 dietary treatments: basal diet (BD), and basal diet supplemented with 600, 700, 800, and 900 mg kg−1of BG. Each of the 5 diets was fed to 4 replicates of 10 chicks each from 0 to 42 days of age. The results indicated that the highest body weight, average daily gain, average daily feed intake, carcass weight, and carcass yield were observed in broilers offered 800 mg kg−1of BG (P < .05). Inclusion of BG improved the feed conversion ratio compared with the control group (P < .01). The calculated European broiler index and crop percentage were greater for the birds received 800 and 900 mg kg−1of BG compared with that of the control birds (P < .05). Inclusion of 900 mg kg−1of BG significantly increased the relative weight of spleen and bursa, but reduced total triglycerides, cholesterol, LDL, and LDL: HDL ratio than the control group (P < .05). The serum IgG and IgM levels were increased for the birds received 700 to 900 mg kg−1BG (P < .01), and addition of BG to the basal diet significantly increased antibody response against sheep red blood cell at 35 days of age (P < .05). It was concluded that an addition of 800 mg kg−1BG to diet improves economic efficiency possibly by creating miniscule improvement in FCR and promoting immune response of broilers. [ABSTRACT FROM PUBLISHER]

Uric acid (UA) is a potent scavenger of oxidants in most mammalian and avian species. The aim of this study was to obtain more comprehensive information regarding the relationship between different concentrations of UA and oxidative balance in chicken cardiac cells. First, oxidative damage parameters were measured in chicken cardiac cells treated with different concentrations of UA. UA concentrations within the normal physiological range had no effect, while treatment with a high level of UA, i.e. 1200 μM, increased the malondialdehyde (MDA) and protein carbonyl contents, decreased the superoxide dismutase (SOD) and catalase (CAT) activities, and had no effect on glutathione (GSH) in cardiac muscle cells. In addition, the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway was stimulated in cells treated with 1200 μM UA. Next, the role of UA in protecting cells from oxidative damage was investigated in hydrogen peroxide (H2O2)-damaged chicken cardiac cells. Treatment with UA within the normal physiological range reduced the increased MDA and protein carbonyl contents and SOD enzymatic activity induced by H2O2 exposure to some extent and inhibited reactive oxygen species (ROS) formation, presumably as a result of the Nrf2 pathway activation in H2O2-damaged cells. By contrast, the MDA and protein carbonyl contents were increased, SOD enzymatic activity was depressed, and the Nrf2 pathway was further down-regulated in H2O2-damaged cells treated with 1200 μM UA. In conclusion, the results indicated that physiological UA concentration partially alleviated oxidative stress in chicken cardiac muscle cells treated with H2O2. However, supraphysiological UA concentrations promoted oxidative damages directly in primary cultured chicken cardiac muscle cells and aggravated oxidative stress in H2O2-damaged cells. [ABSTRACT FROM AUTHOR]

We determined mRNA expression of genes of endothelin-1 (ET-1), and of the transforming growth factor beta ligands (TGFβ1, TGFβ2 and TGFβ3), their receptors (TβRI and TβRII) and their pseudoreceptor BAMBI in the heart of broilers raised under cold temperature conditions and affected by pulmonary hypertension. Gene expression was determined by RT-qPCR in right myocardial ventricle samples from 4-week-old chickens (n = 48) raised either under normal (control) or cold temperature conditions (22 °C versus 14 °C). We do not find differences among healthy birds, birds with cardiac failure and ascitic birds in the mRNA levels of TGFβ2, TGFβ3 and BAMBI. In the control group, ET-1 mRNA level was increased in the ascitic birds as compared with healthy birds and birds with cardiac failure (p < 0.05) whereas in the cold treated group, no increase was observed (p > 0.05); yet, ascitic birds in the cold group showed lower mean than ascitic birds in the control group (p < 0.05). TβRII mRNA expression was higher in ascitic than in healthy birds (p < 0.05) in both control and cold treated groups; however, in the ascitic birds of the cold treated group TβRII expression was lower than in ascitic birds from the control group (p < 0.05). Thus, the higher ET-1 and TβRII levels observed in ascitic birds seem to be attenuated by cold. [ABSTRACT FROM PUBLISHER]

We attempted to determine the growth characteristics of cultured lung fibroblasts of layer type chickens and to investigate presence of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) in these cells in vitro. Lung fibroblasts were isolated, characterized and subcultured from one-day-old layer type chicken lungs. Two different methods, explant culture and enzymatic techniques, were used for culturing and the results were compared. The presence of MMP-2 and TIMP-1 was shown in cultured fibroblasts by immunocytochemical staining, immune blotting and zymography methods. Immune expressions of neither MMP-9 nor TIMP-2 enzymes could be detected. [ABSTRACT FROM AUTHOR]

1. Two experiments were conducted to evaluate the nutritional value of three cultivars (Wallan, Tanjil and Borre) of narrow-leafed lupin (Lupinus angustifolius) for broilers. 2. In Experiment 1, the apparent metabolisable energy (AME) and the apparent ileal amino acid digestibility of the three cultivars were determined. The cultivar effects were not significant for AME and apparent ileal amino acid digestibility coefficients. In general, amino acids in narrow-leafed lupin were well digested, with the notable exception of methionine. Among the indispensable amino acids, arginine had the highest digestibility coefficient (0·92–0·95), while the lowest was for methionine (0·74–0·83). 3. In Experiment 2, using the energy and digestible amino acid values determined in Experiment 1, diets containing 200 g/kg of the three lupin cultivars were formulated and the effects of feeding these diets on the performance and the digestive tract development of broiler starters were investigated. 4. Weight gain, feed intake and feed per gain of broilers fed narrow-leafed lupins diets were similar to those fed on the maize-soy basal diet. The performance of birds fed on diets containing different cultivars of lupins was also similar. Birds fed on lupin diets had similar excreta scores to those fed on the basal diet. 5. Inclusion of 200 g/kg lupins in broiler diets had no effects on the relative weight and length of the intestinal tract. Broilers fed on lupin diets, however, had higher relative weights of liver. 6. These results suggest that narrow-leafed lupins are good sources of protein, but poor sources of AME and sulphur-containing amino acids. It is concluded that, when diets are properly balanced in terms of AME and digestible amino acids, lupins can be included at 200 g/kg inclusion level in broiler starter diets with no adverse effects on performance. [ABSTRACT FROM PUBLISHER]

1. Objectives. To validate the whole blood chemiluminescence (WBCL) assay in chickens, a simple and rapid method of measuring production of reactive oxygen species by circulating polymorphonuclear (PMN) leukocytes. To determine the physiological response and innate immune response associated with oral challenge with Clostridium perfringens in broiler chickens under different nutritional conditions. 2. In Experiment 1, birds were orally challenged with C. perfringens 1. type A or sham-challenged saline on days 14-21 post-hatch and fed protein-balanced diets containing 160 or 180 g crude protein/kg and 0·98 or 1·75% glycine in a 2 × 2 × 2 factorial arrangement of treatments. 2. Challenged birds had higher WBCL responses and more severe intestinal lesions than unchallenged birds. Birds fed diets containing 1·75% glycine had more intestinal lesions than those fed 0·98% glycine. 3. In Experiment 2 birds were fed protein-balanced diets containing 0·76, 2·10, 3·43 or 4·77% glycine. The birds fed 0·76% glycine diet had lower WBCL responses compared to birds fed the other three diets. Intestinal lesions were worse in the birds fed the highest, 4·77% glycine diet than in those fed the 0·76 or 2·10% glycine diets. 4. We conclude that the WBCL assay is a practical and sensitive means of assessing innate immune function in birds. The results suggest that both bacterial challenge and glycine content of chickens' diet influence their lesion scores and innate immune function. [ABSTRACT FROM AUTHOR]

1. It has recently been shown that oxidative stress is involved in the pathogenesis of congestive heart failure (CHF) in broiler chickens. Vitamins E and C, common antioxidants, have been advocated for the prevention of heart failure in humans. The present study examines the effects of supplementation of these vitamins on incidence of CHF and prevention of oxidative stress in the myocardium. 2. Commercial male broilers were randomly allocated to three experimental groups and, respectively, offered commercial broiler diet (control), commercial diets fortified with vitamin E (960 IU/kg) or vitamin C (400 mg/kg). The broilers were monitored daily for overt signs of heart failure and clinical data including ECG and blood gas analysis were collected periodically. Lipid peroxidation was measured in cardiac tissues from apparently normal broilers and broilers developing CHF in each group using thiobarbituric acid reactive substances (TBARS) assay. 3. Overall, the incidence of CHF in broilers given diets fortified with vitamin E or vitamin C was not significantly different as compared to the control group. The incidence of overt signs of hypoxaemia was lower in the vitamin C group than in the control group. Lipid peroxidation was highest in broilers that developed CHF as compared to apparently normal broilers fed either vitamin E or C fortified diets. Neither vitamin E nor vitamin C was effective in preventing oxidative damage in broilers that developed CHF. 4. In conclusion, the present study confirmed that oxidative stress is involved in the pathogenesis of heart failure in broilers, but dietary supplementation of antioxidant vitamins did not prevent oxidative damage in broilers that developed CHF. Beneficial effects of vitamin C supplementation were evidenced by lower incidence of hypoxaemia, and the tendency to reduce the susceptibility of broilers to heart failure. However, vitamin E did not have any impact on clinical status or the incidence of CHF. [ABSTRACT FROM AUTHOR]

1. Standardised data on husbandry were recorded for a flock of birds in one house on each of 150 broiler farms in the UK during the 4 d prior to slaughter. 2. For each flock, the incidence of birds found dead on arrival (DoAs) and the Meat Hygiene Service carcase rejection records were recorded at the slaughterhouse. 3. The mean percentage of birds in each flock found DoA was 0·12% (range 0-0·64%) and the mean percentage of Total Carcase Rejects (TCRs) for each flock was 1·23% (range 0·07-5·51%). 4. A general linear model was developed to examine factors associated with flock percentage DoAs. Assuming a linear relationship, all other factors remaining the same, a one percentage point (PP) increase in small/emaciated birds will result in a 0·155 PP increase in DoAs and a 1 PP increase in wheat in diet 4 will result in a 0·003 PP decrease. An increase by one in the total number of vaccines administered will cause a 0·029 PP decrease in DoAs, a 1 g increase in live weight at slaughter will be associated with a 0·000043 PP increase and a 1 PP increase in mortality on farm would be associated with a 0·000044 PP increase. A 1 PP increase in Ross birds decreases DoAs by 0·0004 PPS: there is also a seasonal effect. 5. The model developed for flock percentage TCRs found that a 1 PP increase in wheat in diet 3 will result in a 0·052 PP decrease in TCRs and a 1 PP increase in Ross birds will cause a 0·009 PP decrease. A 1 PP increase in birds culled on farm will be associated with a 0·03 PP increase in TCRs and the diagnosis of disease during the flock cycle increases TCRs by 0·397 PPs. A one day increase in age at slaughter will result in a 0·046 PP increase in TCRs. [ABSTRACT FROM AUTHOR]

1. This study compared the effect of dietary supplementation with organic or inorganic selenium (Se) sources plus control amounts or large amounts of vitamin E (α-tocopherol acetate) in broilers raised at control (20 to 24°C) or low (14·5 to 16·8°C) temperatures after 2 weeks of age. 2. The following dietary treatments were used from one day old. Diet 1, the control diet, comprised a commercial diet containing 0·15 mg/kg inorganic Se and 50 mg vitamin E/kg feed. Diet 2 was the same as diet 1, supplemented with 0·15 mg/kg inorganic Se. Diet 3 was the same as diet 2 but was supplemented with 200 mg/kg vitamin E. Diet 4 was the same as diet 1, but inorganic Se was replaced with 0·30 mg/kg organic Se. Diet 5 was the same as diet 4, supplemented with 200 mg/kg vitamin E. 3. Low temperature reduced the growth rate of broilers; however, at 6 weeks, there were no differences in the body weights of birds fed on organic Se supplemented diets housed at low or control temperature. The feed conversion ratio was significantly affected by low temperature but not by diet. The heterophil/lymphocyte ratio was higher in chicks after one week in the cold, indicating mild stress. Blood triiodothyronine levels were significantly higher in birds after 1 and 4 weeks in the cold but thyroxin was not affected. 4. Organic Se supplementation increased relative lung weight at the control temperature, which might lead to greater respiratory capacity. Relative spleen weight significantly decreased in broilers fed diets supplemented with inorganic Se under cold conditions, a possible indication of chronic oxidative stress. 5. At the low temperature, supplementation with organic Se alone, or with inorganic Se and vitamin E increased glutathione peroxidase (GSHPx) activity and glutathione (GSH) concentration in the liver of broilers, which may indicate increased activity of birds' antioxidant defence against suboptimal environments. [ABSTRACT FROM AUTHOR]

1. B- and M-mode echocardiography was used to compare cardiac function in broilers with spontaneous ascites syndrome with that of normal chickens. 2. Thirty ascitic chickens and 15 normal chickens aged three, 4, 5 and 6 weeks from the same flock (180 birds in total) were examined. They were restrained gently in a natural standing position, and echocardiographs were obtained with a 7·0-MHz linear transducer placed on the left pectoral apterium. Indices of cardiac structure and functioning were calculated from the echocardiographs, and some were normalised to body weight. Heart rate was also measured. 3. All cardiac structural indices in both ascitic and normal chickens increased with age. Compared with normal chickens, right ventricular diameter at both the end of systole and of diastole was greater in ascitic chickens at all ages. Left ventricular diameter at the end of systole in ascitic chickens was greater at 4, 5 and 6 weeks of age. Ventricular septal thickness at the end of both systole and diastole was greater in ascitic chickens at 5 and 6 weeks. Left ventricular free wall thickness at the end of diastole was less in ascitic chickens at 3 weeks. However, all the structural indices decreased with age after normalisation with body weight. 4. The heart rate of ascitic chickens was lower at 4, 5 and 6 weeks. Normalised left ventricular fractional shortening was lower in ascitic chickens at 4, 5 and 6 weeks, as was normalised right ventricular fractional shortening. Incrassation of the ventricular septum (ΔT), which changed little in normal chickens, was less at 4, 5 and 6 weeks in ascitic chickens. Left ventricular fractional shortening, right ventricular fractional shortening and ΔT were all negatively correlated with ascites heart index at all ages. 5. Taken together the results suggest heart failure of both ventricles, but that right ventricular dysfunction is more extensive than left ventricular dysfunction. We suggest that secondary pulmonary hypertension would result in these ascitic chickens due to volume overload. [ABSTRACT FROM AUTHOR]

1. The effects of acute heat stress (2&ThickSpace;h at 32°C and 75% RH) on body temperature and indices of respiratory thermoregulation and skeletal muscle function were examined in two divergently selected male grandparent lines of broiler and layer-type chickens at two ages (35 and 63&ThickSpace;d), or at a similar body weight (&nvsim;2·2&ThickSpace;kg). 2. The two chicken lines exhibited markedly different baseline blood acid–base and skeletal muscle characteristics. At the same age or live weight, birds from the broiler line had significantly higher venous blood carbon dioxide tensions associated with lower blood pH. Plasma creatine kinase (CK) activities reflecting muscle membrane damage were also greatly elevated in the broiler line. 3. Exposure to acute heat stress caused an increase in deep body temperature, panting-induced acid–base disturbances and elevated plasma CK activity in both lines of chicken, an effect that increased with age. The extent of disturbances in acid–base regulation and heat-stress-induced myopathy were more pronounced in the broiler than the layer line at the same age or similar live weights. 4. It is suggested that genetic selection for high muscle growth in broiler lines has compromised their capacity to respond to an acute thermal challenge, leading to detrimental consequences for muscle function. This reduction in heat tolerance may have important implications for bird welfare and subsequent meat quality. [ABSTRACT FROM AUTHOR]

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1. Genetic parameters for the sudden death syndrome (SDS) were estimated in meat-type chickens. Data were collected over 11 generations of selection for body weight within two distinct breeds (Cornish and White Rock).2. The animal model was used exclusively with linear methods (LM) to estimate genetic parameters. Heritability (h 2 ) of SDS on the liability scale was 0&CenterDot;30?&PlusMinus;?0&CenterDot;002 and 0&CenterDot;25?&PlusMinus;?0&CenterDot;002 in the Cornish and White Rock breeds, respectively.3. A positive genetic correlation (rg) with ascites (AS) was determined (~0&CenterDot;3?&PlusMinus;?0&CenterDot;006). However, it was not possible to estimate the rg of SDS with body weight because of the low prevalence of the defect trait studied (1&CenterDot;8% in the Cornish and 1&CenterDot;5% in the White Rock).4. Heritability of SDS calculated using male records only was 0&CenterDot;45?&PlusMinus;?0&CenterDot;009 and 0&CenterDot;35?&PlusMinus;?0&CenterDot;009, and rg with body weight was 0&CenterDot;30?&PlusMinus;?0&CenterDot;010 and 0&CenterDot;27?&PlusMinus;?0&CenterDot;009, in the Cornish and White Rock breeds, respectively.5. In conclusion, the heart defect investigated was heritable with a positive genetic correlation with AS and body weight. [ABSTRACT FROM AUTHOR]

1. Pulmonary hypertension syndrome followed by ascites is a metabolic disorder in broilers that occurs more often in fast-growing birds and at cool temperatures.2. Knowledge of the genetic relationships among ascites-related traits and performance traits like carcase traits or feed efficiency traits is required to design breeding programmes that aim to improve the degree of resistance to ascites syndrome as well as production traits. The objective of this study was to estimate these genetic correlations.3. Three different experiments were set up to measure ascites-related traits (4202 birds), feed efficiency traits (2166 birds) and carcase traits (2036 birds). The birds in different experiments originated from the same group of parents, which enabled the estimation of genetic correlations among different traits.4. The genetic correlation of body weight (BW) measured under normal conditions and in the carcase experiment with the ascites indicator trait of right ventricle to total ventricle ratio (RV:TV) measured under cold conditions was 0&CenterDot;30. The estimated genetic correlation indicated that single-trait selecting for BW leads to an increase in occurrence of the ascites syndrome but that there are realistic opportunities of multi-trait selection of birds for improved BW and resistance to ascites.5. Weak but positive genetic relationships were found between feed efficiency and ascites-related traits suggesting that more efficient birds tend to be slightly more susceptible to ascites.6. The relatively low genetic correlation between BW measured in the carcase or in the feed efficiency experiments and BW measured in the ascites experiment (0&CenterDot;49) showed considerable genotype by environment interaction. These results indicate that birds with high genetic potential for growth rate under normal temperature conditions have lower growth rate under cold-stress conditions due to ascites. [ABSTRACT FROM AUTHOR]

The present study was designed to investigate the effect of different atmospheric pressure on the endogenous functions of broiler chickens during embryonic, hatching and growing periods related to ascites. Eggs from a commercial broiler line were incubated in two similar commercial incubators at high and low altitudes. The effect on embryonic development and physiological functions including hatching parameters, incidence of ascites and growth performance were examined. Embryos incubated at high altitude had higher plasma tri-iodothyronine, thyroxine, corticosteroid and lactic acid levels, and hatched earlier than those incubated at low altitude. Embryonic mortality was higher at high altitude. Chickens that had been incubated at high altitude showed less right ventricular hypertrophy and ascites mortality than those incubated at low altitude. It was concluded that different atmospheric pressure during incubation interacts with the endocrine functions of the embryo and hence affects hatching parameters, thereby influencing ascites susceptibility. [ABSTRACT FROM AUTHOR]