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Objective: The objective of this study was to determine whether a dietary vitamin E (VE) supplement could alleviate any detrimental effects of aged corn on lipid metabolism and antioxidant status in laying hens. Methods: The experiment consisted of a 2×3 factorial design with two corn types (normal corn and aged corn (stored for 4 yr) and three concentrations of VE (0, 20, and 100 IU/kg). A total of 216 Lohmann laying hens (50 wk of age) were randomly allocated into six treatment diets for 12 wk. Each treatment had 6 replicates of 6 hens per replicate. Results: The results show that aged corn significantly decreased the content of low-density lipoprotein cholesterol (p<0.05), and reduced chemokine-like receptor 1 (CMKLR1) mRNA expression (p<0.05) in the liver compared to controls. Diet with VE did not alter the content of crude fat and cholesterol (p>0.05), or acetyl-CoA carboxylase, lipoprotein lipase, fatty acid synthase or CMKLR1 mRNA expression (p>0.05) in the liver among treatment groups. Aged corn significantly increased the content of malondialdehyde (MDA) (p<0.05) and decreased superoxide dismutase (SOD) activity (p<0.05) in the liver. The VE increased the content of MDA (p<0.05) but decreased glutathione peroxidase (GSH-Px) activity in serum (p<0.01) and in the ovaries (p<0.05). Adding VE at 20 and 100 IU/kg significantly increased GSH-Px activity (p<0.05) in liver and in serum (p<0.01), 100 IU/kg VE significantly increased SOD activity (p<0.05) in serum. Aged corn had no significant effects on GSH-Px mRNA or SOD mRNA expression (p<0.01) in the liver and ovaries. Addition of 100 IU/kg VE could significantly increase SOD mRNA expression (p<0.01) in the liver and ovary. Conclusion: Aged corn affected lipid metabolism and decreased the antioxidant function of laying hens. Dietary VE supplementation was unable to counteract the negative effects of aged corn on lipid metabolism. However, addition of 100 IU/kg VE prevented aged corninduced lipid peroxidation in the organs of laying hens. [ABSTRACT FROM AUTHOR]

Genetic selection and intensive nutrition for increased growth rate in meat-type ducks has resulted in an imbalance between pectorales increment and sternal mass, which is detrimental to productivity and welfare. Reducing body weight and increasing sternal mass probably reverses these adverse effects. Therefore, 2 experiments (Expt.) were conducted to investigate the effects of 25-hydroxycholecalciferol (25-OH-D3), a vitamin D3 metabolites, on sternal mass. In Expt. 1, 512 1-day-old male ducks were randomly assigned to 4 low-nutrient density diets and received following treatments in a 2 × 2 factorial arrangement: (i) NRC or China Agricultural industry standards (NY/T) vitamin premixes and (ii) 0.069 mg/kg 25-HyD in feed or not. At 49 D of age, regardless of 25-OH-D3, NY/T vitamin regimen inhibited bone turnover and consequently increased sternal trabecular bone volume and mineral deposition compared with NRC vitamin premix. Supplementing 25-OH-D3 to NRC but not NY/T vitamin regimen significantly improved sternal microarchitecture and mineral content, which companied by decreased serum bone resorption markers concentration, as well as downregulation of the gene expressions of osteoclast differentiation and activity. In Expt. 2, 256 1-day-old male ducks were fed a standard nutrient density diet contained NRC vitamin premix with 0 or 0.069 mg/kg of 25-OH-D3. Results also showed that 25-OH-D3 treatment significantly improved sternal mineral accumulation and microarchitecture, along with decreasing osteoblast and osteoclast numbers in bone surface, declining serum bone turnover markers levels, and increasing serum Ca concentration. Collectively, these findings indicated that the dietary administration of 25-OH-D3 increased sternal mass in NRC vitamin diet by suppressing bone resorption in 49-day-old meat duck. [ABSTRACT FROM AUTHOR]

Three experiments were conducted to investigate the effects of maternal dietary canthaxanthin (CX) and 25-hydroxycholecalciferol (25-OH-D3) supplementation on antioxidant status and calciumphosphate metabolism of progeny ducks. Cherry Valley duck breeders (38 wk old) were fed either a control diet or the same diet plus CX (6 mg/kg) and 25-OH-D3 (0.069 mg/kg) for 32 weeks. Experiments 1, 2, and 3 were conducted with progeny ducks hatched from eggs laid by duck breeder hens at 54, 62, and 70 wk of age, respectively. Progeny ducks from both maternal treatments were fed with the same NRC (1994) vitamin regimen starter (1 to 14 d) and finisher (15 to 35 d) diets in experiments 1 and 2, and fed with the same high vitamin regimen starter (1 to 14 d) and finisher (15 to 35 d) diets in experiments 3. High vitamin regimen had higher levels of all vitamins, except biotin, than the NRC (1994) vitamin regimen. In experiment 1, maternal CX and 25-OH-D3 increased (P < 0.05) shank pigmentation and tibiotarsus ash and tended to decrease (P < 0.1) liver total superoxide dismutase activity (T-SOD) of one-day-old progeny ducks; and increased (P < 0.05) shank pigmentation, decreased (P = 0.05) liver protein carbonyl, and tended to increase (P < 0.1) liver total antioxidant capacity (T-AOC) of 14-day-old progeny ducks. In experiment 2, maternal CX and 25-OH-D3 increased (P < 0.05) shank pigmentation and liver T-AOC and decreased (P < 0.05) liver protein carbonyl of one-day-old progeny ducks, but increased (P < 0.05) the serum phosphate level of 14-day-old progeny ducks. In experiment 3, maternal CX and 25-OH-D3 increased (P < 0.05) shank pigmentation of one-, 14-, and 35-day-old progeny ducks and tended to increase (P < 0.1) liver T-SOD and tibiotarsus ash, but decrease (P < 0.1) liver malondialdehyde of one-day-old progeny ducks. It can be concluded that progeny dietary high vitamin regimen could partially prevent maternal CX-derived progeny shank pigmentation from bleaching. Maternal CX- and 25-OH-D3-derived effects are influenced by the hen's age and progeny's dietary vitamin regimen. [ABSTRACT FROM AUTHOR]

A study was conducted to establish the response of Pekin ducks to dietary Met from 15 to 35 d age. Experimental diets were formulated to contain 0.35, 0.45, 0.55, 0.65, and 0.75% Met (0.30, 0.39, 0.45, 0.56, and 0.68% on an analyzed basis, respectively) and 0.3% cysteine (0.25, 0.27, 0.26, 0.26, and 0.28% on an analyzed basis, respectively). Each diet was fed to 10 pens of 55 ducks/pen. Carcass yields and feather growth were determined at 28 and 35 d. Results showed that feeding 0.30% Met (0.55% Met+Cys) significantly impaired ADG, feed-to-gain (F:G) ratio, breast meat yield, and feather growth in comparison to the other dietary treatments (P < 0.05). BW, ADG, F:G, carcass and breast meat weight and yield, breast skin and subcutaneous fat weight and yield, the fourth primary wing feather length, and feather coverage showed significant quadratic broken-line or quadratic polynomial response to increasing dietary Met (P < 0.05). From 15 to 28 d age, the optimal Met requirement for the BW, breast meat yield, and the fourth primary wing feather length were 0.510, 0.445, and 0.404%, respectively, based on quadratic broken-line model, and correspondingly were 0.606, 0.576, and 0.559% by quadratic regression. For ducks from 15 to 35 d age, the optimal Met requirement for BW, breast meat yield, and feather coverage were 0.468, 0.408, and 0.484%, respectively, by quadratic broken-line model, and 0.605, 0.564, and 0.612%, by quadratic regression, respectively. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the responses of meat ducks of 15 to 35 d of age to free gossypol (FG) from cottonseed meal (CSM) and to establish the maximum limits of dietary FG concentration based on growth performance, blood parameters, and tissue residues of gossypol. Nine hundred 15-d-old ducks were randomly allocated to 5 treatments with 10 cages/treatment and 18 ducks/cage on the basis of BW. Five isonitrogenous and isocaloric experimental diets were formulated on a digestible amino acid basis to produce diets in which 0% (without FG), 25% (36mg FG/kg), 50% (75mg FG/kg), 75% (111 mg FG/kg), and 100% (153 mg FG/kg) of protein from soybean meal were replaced by that from CSM. Increasing dietary FG content, BW, and ADG decreased (linearly, P < 0.05, except for ADG of days 29 to 35), and F/G linearly increased (P < 0.05). At 35 d, blood hemoglobin, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration linearly decreased (P < 0.05), while serum total protein, albumin, and globulin content linearly decreased (P < 0.05), and the residue of gossypol in liver, kidney, heart, breast, and leg muscle linearly increased (P < 0.001) with increases in dietary FG concentration. Ducks fed 36 mg FG/kg (5.83% CSM of diet) diet had a normal histological structure of liver, and muscle (breast and leg) had no residue of gossypol. The maximum limit of dietary FG concentration was estimated to range from a low of 36 mg/kg to maximize serum globulin concentration to a high of 124 mg/kg to minimize feed intake for 22 to 28d on the basis of a quadratic broken-line model. [ABSTRACT FROM AUTHOR]

A study was conducted to determine the influence of dietary energy and protein concentrations on growth performance and carcass traits of Pekin ducks from 15 to 35 d of age. In experiment 1, 14-d-old ducks were randomly assigned to 3 dietary metabolizable energy (11.8, 12.8, and 13.8 MJ/kg) and 3 crude protein concentrations (15, 17, and 19%) in a 3 × 3 factorial arrangement (6 replicate pens; 66 ducks/pen). Carcass characteristics were evaluated on d 28, 32, and 35. In Experiment 2, 15-d-old ducks (6 replicate cages; 6 ducks/cage) were randomly allotted to the 9 diets that were remixed with 0.5% chromic oxide. Excreta were collected from d 17 to 19, and ileal digesta was collected on d 19 to determine AMEn and amino acid digestibility. In Experiment 1, there were interactions (P < 0.05) between dietary metabolizable energy and crude protein (CP) on body weight (BW) gain and feed intake, wherein BW gain increased more to increasing dietary CP as dietary metabolizable energy increased. However, feed intake was only influenced by dietary crude protein at 11.8 MJ ME/kg and not 12.8 or 13.8 MJ/kg. As dietary CP increased from 15 to 19%, breast meat yield increased by 10.8% on d 35 (P < 0.01). Conversely, increasing metabolizable energy from 11.8 to 13.8 MJ/kg increased dressing percentage, breast skin, and subcutaneous fat, but decreased breast meat yield (% but not weight) on d 35 (P < 0.01). In Experiment 2, the determined AMEn for diets formulated to contain 11.8, 12.8, or 13.8 MJ ME/kg were 11.66, 12.68, and 13.75 MJ/kg, respectively; determined standardized ileal digestible Lys was 0.95, 1.00, and 1.21% for diets formulated to contain 15, 17, or 19% crude protein, respectively. The best body weight gain and feed conversion ratio was obtained when ducks were fed a high dietary AMEn (13.75 MJ/kg) and high CP (19%, 1.21% SID Lys). These results provide a framework for subsequent modeling of amino acid and energy inputs and the corresponding outputs of growth performance and carcass components. [ABSTRACT FROM PUBLISHER]

The most stable structures of gaseous Si m C n (3 ⩽ n+ m ⩽ 6) clusters in their ground electronic states are determined with the high level electronic correlation method QCISD(T)/g3large. Thermodynamic properties on heat capacity ( C ), entropy ( S ), Gibbs energy function (−[ G Θ − H Θ( T r )]/ T) and enthalpy function ( H Θ− H Θ( T r )) are predicted with standard statistical thermodynamics using the structure parameters and vibrational frequencies obtained with B3PW91/6-31G( d) method combined with the electronic excitation energies determined with time dependent density functional (TD DFT) method at B3PW91/6-31G( d) level. The electronic energies are calculated with the accurate model chemistry method at G3(QCI) level of theory and the Δ f H (0 K), Δ f H (298.15 K) and Δ f G (298.15 K) values are predicted. The heat capacities C ( T) as a function of temperature within 298.15-2000 K are fitted into analytical equations. The thermodynamic functions at higher temperatures are determined classically by using these equations. Most of the results obtained in this work are consistent with the available experiments. [ABSTRACT FROM AUTHOR]

The transcription factor early growth response gene (Egr-1) is a stress response gene activated by various forms of stress. The effect of silica on transcription and expression of Egr-1 was investigated in rat lung and in RAW264.7 cells. Silica induced the expression of Egr-1 in vivo and was mainly located in alveolar macrophage cells and lung epithelial cells. Furthermore, silica induced Egr-1 mRNA and protein expression in cultured RAW264.7 cells. Immunofluorescence microscopy revealed translocation of Egr-1 to the nucleus in response to silica. The contribution of the extracellular signal-regulated kinase (ERK) pathway to the activation of Egr-1 in response to silica was examined. Exposure to silica resulted in a rapid phosphorylation of ERK 1/2 kinases in RAW264.7 cells. MAP Kinase Kinase (MEK) inhibitor U0126 prevented Egr-1 induction by silica. The results suggest that silica could induce Egr-1 activation in macrophages in vivo and in vitro and that phosphorylated ERK 1/2 may be involved in this action. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of dietary canthaxanthin (CX) and 25- hydroxycholecalciferol (25-OH-D3) supplementation on the antioxidant status and tibia quality of duck breeders and newly hatched ducklings. In total, 780 female and 156 male duck breeders were randomly allotted to 2 treatments. Duck breeders were fed either a commercial diet (containing 3,000 IU/kg vitamin D3) or the same diet plus a mixture of CX (6 mg/kg) and 25-OH-D3 (0.069 mg/kg) for 40 wk. The antioxidant status of duck breeders, egg yolk, and ducklings; tibia quality of duck breeders and ducklings; and shell quality of breeder eggs were investigated. The total antioxidant capacity of breeder female liver (P = 0.028), breeder male testis (P = 0.049), egg yolk (P = 0.032), one-day-old duckling liver (P = 0.024), and one-day-old duckling yolk sac (P = 0.012) were increased by dietary supplementation of the mixture of CX and 25-OH-D3. The inclusion of CX and 25-OH-D3 decreased liver protein carbonyl of breeder females (P = 0.030), and liver malonaldehyde (P = 0.050) and protein carbonyl (P = 0.030) of breeder males. Yolk (P < 0.001), shank (P < 0.001), and yolk sac pigmentation (P < 0.001) of one-day-old ducklings were increased by the supplementation of the CX and 25-OH-D3 mixture. No differences (P > 0.05) were observed in tibia quality or eggshell quality between treatments. In conclusion, the inclusion of the mixture of CX and 25-OH-D3 in a diet sufficient in vitamin D3 increased antioxidant status but not tibia quality of duck breeders and newly hatched ducklings. [ABSTRACT FROM AUTHOR]

The study was conducted to determine the effects of low ambient temperature (LAT) and a vitamin C (VC) dietary supplement on the growth performance, blood parameters, and antioxidant capacity of 21-d-old broilers. A total of 400 one-day-old male Cobb broilers were assigned to 1 of 4 treatments as follows: 1) LAT and a basal diet; 2) LAT and a basal diet supplemented with 1,000 mg of VC/kg (LAT + VC); 3) normal ambient temperature (NAT) and a basal diet; 4) NAT and a basal diet supplemented with 1,000 mg of VC/kg (NAT + VC). All birds were fed to 21 d of age. Broilers in groups 1 and 2 were raised at 24 to 26°C during 1 to 7 d, and at 9 to 11°C during 8 to 21 d, whereas groups 3 and 4 were raised at 29 to 31°C during 1 to 7 d and at 24 to 26°C during 8 to 21 d. The LAT increased the feed conversion ratio during the whole experimental period (P < 0.01), whereas it increased heart index at 21 d (P < 0.05) and hematocrit and hemoglobin level at 14 d (P < 0.05). Supplementing the diet with VC increased hematocrit, hemoglobin, and red blood cell count at 21 d (P < 0.05). At 21 d, LAT conditions decreased total antioxidant capacity in the serum, liver, and lungs (P < 0.05), and it also increased the levels of VC in the serum and liver, the amount of protein carbonylation in liver and lungs, and the malondialdehyde level in the lungs (P < 0.05). The addition of VC tended to increase the total antioxidant capacity level in serum (P < 0.1). Low ambient temperature resulted in oxidative stress for broilers that were fed from 1 to 21 d of age, whereas no significant effect was found on the antioxidant activity by dietary VC supplementation. [ABSTRACT FROM AUTHOR]

Dietary vitamin E supplementation has been indicated to enhance the antioxidant capacity of breeders. As breeders age, the productive and reproductive performance rapidly decline, and dietary vitamin E supplementation may play a positive role in this process. Two trials were conducted to evaluate the effects of dietary vitamin E supplementation on laying performance, hatchability traits and antioxidant status in molted broiler breeder hens beyond 70 wk. A total of 512 (71-week-old) and 576 (75-week-old) molted Ross 308 breeder hens were assigned to 2 dietary vitamin E groups (6 or 100 mg/kg) and 3 dietary vitamin E groups (100, 200 or 400 mg/kg) for 12 wk, respectively. Eggs were collected and incubated at wk 9. Dietary vitamin E supplementation did not affect the laying performance of hens and the hatchability traits of eggs (P > 0.05). As dietary vitamin E concentration increased, the malonaldehyde (MDA) content in ovarian of hens, egg yolks and serum, brain, and yolk sac of chicks decreased (P < 0.05), the total antioxidant capacity (T-AOC) in serum and ovarian of hens, egg yolks and yolk sac of chicks increased (P < 0.05), and the alpha-tocopherol content in egg yolks increased (P < 0.05). In conclusion, dietary vitamin E supplementation did not influence egg production and hatchability traits. However, based on optimizing the antioxidant status of egg yolks and newly hatched chicks, the suitable vitamin E concentration in the molted broiler breeder hen (beyond 70 wk) diet is at least 200 mg/kg. [ABSTRACT FROM AUTHOR]

A total of 560 one-day-old Pekin ducks were randomly allocated to 7 treatments with 8 replicate cages of 10 ducks per cage. The treatments included a corn-rice bran-soybean meal-based diet with recommended nonphytate phosphorus (NPP) (0.40% for 1-14 D/0.35% for 15-35 D, positive control; PC), NPPdeficient diet (0.22% for 1-14 D/0.18% for 15-35 D, negative control; NC), and NC diets supplemented with different levels of phytase (500, 2,500, 5,000, 7,500, 10,000 FTU/kg). Compared with the PC diet, feeding the NC diet significantly decreased (P, 0.05) the bird growth performance, serum total protein, and albumin concentration as well as tibia bone mineralization and strength and increased (P, 0.05) serum calcium (Ca), urea content, and alkaline phosphatase activity throughout the experimental period. Phytase supplementation to NC diets at 5,000 to 10,000 FTU/kg restored (P, 0.05) growth performance, serum biochemical parameters, and tibia traits when compared with the levels of the PC. Moreover, the addition of phytase linearly increased (P, 0.05) dietary protein, Ca, and phosphorus (P) utilization as well as nitrogen output, and excreta iron, copper, manganese, and zinc concentration quadratically increased (P, 0.05) as well as P output. In conclusion, phytase at 5,000 FTU/kg was effective in ameliorating the negative effects of NC diets and reducing trace mineral supplementation in diet of Pekin ducks. [ABSTRACT FROM AUTHOR]

This study was conducted to determine whether protein solubility (PS) of rapeseed meals (RSM) can affect standardized ileal amino acid digestibility (SIDAA) in meat ducks. A total of 1,168, 14-days-old ducks were randomly allotted to 23 treatments (6 cages per diet, 8 ducks per cage) and 1 nitrogen-free diet treatment (8 cages, 8 ducks per cage) based on body weight. The 23 experimental diets consisted of a corn–soybean meal basal diet, and 22 diets containing 15% RSM: 85% basal diet. Titanium dioxide (0.5%) was included in all diets as an indigestible marker. On day 18, all ducks were euthanized by carbon dioxide asphyxiation and digesta samples from the ileum. The contents of PS, ether extract (EE), glucosinolate, isothiocyanate, and oxazolidine were significantly different (P < 0.05) in the 22 RSM, with the CV being 52.62, 49.23, 86.84, 90.19, and 81.98%, respectively. The content of lysine (Lys) and methionine in the 22 RSM samples ranged from 1.03 to 2.71% (CV 24.19%) and from 0.33 to 0.65% (CV 15.17%), respectively. The SIDAA, except for leucine (Leu) and tyrosine, of the 22 RSM samples varied significantly (P < 0.05). A positive correlation was observed (P < 0.05) between PS and standardized ileal digestibility (SID) of Lys, isoleucine, valine, phenylalanine, histidine, serine, cysteine, and tyrosine. The R² value of multiple linear regression equations for predicting the SID of amino acids (AA) was best for Lys (R2 = 0.958 using dry matter, crude protein, EE, crude fiber, acid detergent fiber, and PS) and least significant for Leu (R² = 0.348 using crude fiber and ash) with intermediate values for other AA (R² = 0.359–0.837, P < 0.05). These results suggest that PS varying from 15.06 to 98.08%, also varied considerably in the proximate nutrient content, AA composition, and antinutritional factor content, which was reflected in considerable differences in the duck's SID of AA in RSM. Therefore, PS value can partly reflect the quality of RSM. [ABSTRACT FROM AUTHOR]

Foot pad dermatitis (FPD) is a serious problem of the modern poultry industry, negatively affecting birds' welfare and health status, walking and feeding activity, growth performance, carcass quality, and economic performance of meat production. The gut microbiome in poultry with FPD has not been previously investigated. Therefore, we compared the cecal microbiomes of 8 breeding ducks with FPD to 8 control ducks (breeders with apparently healthy feet) by pyrosequencing the bacterial 16S ribosomal RNA gene. The results showed a significant β-diversity (P < 0.05) of cecal microbiota presented between healthy and FPD-affected breeder ducks. The plasma endotoxins, interleukin 1β (IL-1β), IL-17, IL-6, IL-10, and tumor necrosis factor-α concentration, and the abundance of class Clostridia in FPD-affected ducks was markedly higher (P < 0.05), however, the abundance of genus Prevotella, Lactobacillus, Lachnospiraceae UCG-008, and the Firmicutes to Bacteroidetes ratio in FPD-affected ducks was significantly lower (P < 0.05) when compared to healthy ducks. These findings suggest when duck breeders are affected with FPD, ducks show an increased inflammatory response and a difference of structure and composition of the cecal microbiome. [ABSTRACT FROM AUTHOR]

This study was to determine the effects of rapeseed oil on production performance, egg quality, and serum parameters in laying hens. A total of 1,080 hens (33-wk-old) were randomly divided into a 1 plus 4 × 2 factorial design including four different rapeseed oil sources [high erucic acid of Mianyang city (MH); high erucic acid of Deyang city (DH); low erucic acid of Mianyang (ML); low erucic acid of Deyang (DL)] at two levels (2% and 4%) for 12 wk. The egg production and egg weight were decreased (P < 0.05) during 9 to 12 wk and 1 to 12 wk, while the average daily feed intake (ADFI) and feed conversion ratio were decreased (P < 0.01) in all phases compared to the control group. Adding ML as oil source had higher (P < 0.05) egg weight compared to DH in all periods in spite of levels. Meanwhile, layers fed 4% rapeseed oil decreased (P < 0.01) egg production compared with 2% in all phases except 1 to 4 wk. Regardless of rapeseed oil sources, hens fed 4% oil decreased (P < 0.05) egg weight in contrast to 2% during the whole experiment except 5 to 8 wk. The ADFI was lower (P < 0.01) in 4% oil inclusion groups compared with 2% during overall phase. Rapeseed oil decreased the yolk color (P < 0.01) and yolk ratio (P = 0.02) and increased (P < 0.01) the albumen height and Haugh unit at 12 wk. Dietary rapeseed oil supplementation resulted in a decreased total triglyceride (TG; P < 0.01) and increased high-density lipoprotein cholesterol (P = 0.02). Regardless of rapeseed oil levels, layers fed MH had higher TG (P < 0.01), TC (P < 0.05), low-density lipoprotein cholesterol (P < 0.05), alanine transaminase (P < 0.01) than those fed other sources. Taken together, the addition of rapeseed oil decreased laying performance, reduced TC and TG in the serum, and increased Haugh unit, with low erucic acid or 2% group showed more pronounced results among all treatments. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the effect of dietary energy concentration on growth performance, serum biochemical indices, and the mRNA expression of inflammatory cytokines in the liver of meat ducks challenged with lipopolysaccharide (LPS). A total of 600 1-d-old Cherry Valley meat ducks were randomly assigned to 10 treatments with six replicate cages of 10 birds/pen. A 5 × 2 factorial arrangement in a complete randomized design experiment was used to study the effect of five concentrations of dietary metabolizable energy (ME, 2,800, 2,900, 3,000, 3,100, and 3,200 kcal/kg) with or without a challenge with LPS in meat ducks. All experimental ducks were intraperitoneally injected with either 0.5 mg/kg body weight (BW) LPS or an equivalent amount of sterile saline at 15, 17, and 19 d of age. The results showed that LPS challenge significantly decreased (P < 0.05) BW (d 21), body weight gain (d 15–21) and average daily feed intake (ADFI; d 15–21), and markedly increased (P < 0.05) relative spleen weight, serum total protein concentration, and the mRNA expression of interleukin 6 (IL-6), interleukin 10, transforming growth factor β (TGF-β), and Avian Beta Defensin 10 (AVBD-10) in the liver of meat ducks. Ducks fed 3,200 kcal/kg ME diet had the lowest (P < 0.05) ADFI than those fed with the other diets. Additionally, there were significantly LPS by diet interactions on IL-6, interferon-γ, TGF-β, AVBD-10, and inducible nitric oxide synthase mRNA expression (P < 0.05), wherein a more pronounced liver inflammatory response was observed in birds fed high-energy diets (3,100 and 3,200 kcal/kg ME) than birds fed low-energy diet (2,800 and 2,900 kcal/kg ME). The results indicated that 3,100 and 3,200 kcal/kg ME of diets increased hepatic inflammatory markers induced by LPS challenge in ducks but did not influence performance responsiveness during this challenge. [ABSTRACT FROM AUTHOR]

The objective of the study was to investigate the effects of deficiency or high level addition of methionine (Met) in diet on homocysteine (Hcy) metabolism and hepatic lipid metabolism in broiler. A completely random design was used with 3 dietary treatments with the addition of Met from DL-methionine (DLM) at 0%, 0.22%, and 0.32% in a basal diet. The analyzed dietary Met was 0.271%, 0.485%, and 0.584% respectively for the Met-deficient, sufficient, and excessive diet. A total of 360 one-day-old male Ross 308 broiler chicks were randomly assigned to the treatments. The trial was last for 21 d. Compared to the Met-sufficient diet, the Met-deficient diet significantly resulted the decrease of 1 to 21 d growth performance and the increase of liver ether extract (EE). Compared to the Met-sufficient group, the expression of lipid transport gene apolipoprotein B (APOB) in both Met-deficient and Met-excessive group was decreased (P < 0.05). However, compared to the Met-sufficient group, a decreased of serum low-density lipoprotein cholesterol (LDLC) was only shown in birds fed a Met-deficient diet (P < 0.05). Although the plasma Hcy content was decreased, the expression of Cystathionine β-synthase (CβS) and hepatic inflammatory cytokines included interleukin-1 (IL-1) and interleukin-8 (IL-8) was significantly decreased in birds fed the Met-deficient diet when compared to those in Met-sufficient group (P < 0.05). When compared to the Met-sufficient group, the broilers in high dietary Met group had increased levels of catabolic enzyme genes expression especially acyl-coenzyme A oxidase 1 (ACOX1) and carbohydrate response element-binding protein (CHREBP) (P < 0.05), and a decreased content of liver EE. In conclusion, dietary Met deficiency decreased the hepatic lipid export and subsequently increased the hepatic lipid accumulation. High dietary Met addition increased the hepatic lipid catabolism and subsequently decreased the liver lipid accumulation. [ABSTRACT FROM AUTHOR]

The study was conducted to distinguish the effect of dietary non-phytate phosphorus (NPP) levels on the community diversity and structure of the cecal microbiota in meat duck based on 16S rDNA high-throughput sequencing. In total, 525 1-d-old ducklings were fed diets (105 ducklings, 7 pens of 15 ducklings, on each diet) containing five levels of NPP (0.22, 0.34, 0.40, 0.46, and 0.58%) for 21 days. The results showed that dietary NPP levels linearly and quadratically increased (P < 0.05) 21 d body weight, 1 to 21 d feed intake and NPP intake, and contrarily, linearly decreased (P < 0.05) β-diversity of cecal microbial population in ducks. ß-diversity analyses showed that microbiota clustering based on dietary NPP levels occurred, with 0.22% NPP groups distinctly different from the 0.46% and 0.58% NPP group samples. Moreover, dietary NPP levels could change the relative abundance of the phylum Proteobacteria (linear, P < 0.05), genera Eubacterium coprostanoligenes (quadratic, P < 0.05), Ruminococcaceae UCG-014 (quadratic, P < 0.05) and Subdoligrannulum (linear, P < 0.05), and Lachnospiraceae family (quadratic, P < 0.05) in cecal microbiota of ducks. Increasing the dietary NPP level influenced the cecal microbiota and positively affected the growth of meat ducks. [ABSTRACT FROM AUTHOR]