Stress In Broiler Chickens Research Articles

The association of Hsp90 expression induced by aspirin with anti-stress damage in chicken myocardial cells.

The protective effect of aspirin during exposure to heat stress in broiler chickens was investigated. We assayed pathological damage, expression and distribution of Hsp90 protein and hsp90 mRNA expression in chicken heart tissues after oral administration of aspirin following exposure to high temperature for varying times. Heat stress induced increases in plasma aspartate aminotransferase, creatine kinase and lactate dehydrogenase activities while causing severe heart damage, which was characterized by granular and vacuolar degeneration, nuclear shrinkage and even myocardium fragmentation in cardiac muscle fibers. After aspirin administration, myocardial cells showed fewer pathological lesions than broilers treated with heat alone. A high positive Hsp90 signal was always detected in the nuclei of myocardial cells from broilers treated with aspirin, while in myocardial cells treated with heat alone, Hsp90 in the nuclei decreased, as did that in the cytoplasm. Aspirin induced rapid and significant synthesis of Hsp90 before and at the initial phase of heat stress, and significant expression of hsp90 mRNA was stimulated throughout the experiment when compared with cells exposed to heat stress alone. Thus, specific pre-induction of Hsp90 in cardiovascular tissue was useful for resisting heat stress damage because it produced stable damage-related enzymes and fewer pathologic changes.

Effects of Chromium (III) Picolinate and Chromium (III) Picolinate Nanoparticles Supplementation on Growth Performance, Organs Weight and Immune Function in Cyclic Heat Stressed Broiler Chickens

Effects of Chromium (III) Picolinate and Chromium (III) Picolinate Nanoparticles Supplementation on Growth Performance, Organs Weight and Immune Function in Cyclic Heat Stressed Broiler Chickens

Heat shock protein 70 mRNA expression and immune response of heat-stressed finishing broilers fed propolis (bee glue) supplementation

Abstract. This 2×2 factorial experiment investigated the efficacy of propolis (bee glue; BG) in ameliorating heat-stress-induced impairment of growth performance, the hematological profile, intestinal morphology, and biomarkers of heat stress in broilers. Two hundred and forty 21-day old Ross 308 male broiler chicks were allocated to four experimental treatments in six replicates of 10 birds each. The main factors were composed of diet (basal diet or addition of 3 g kg−1 of BG) and temperature (thermoneutral or heat stress). Broilers subjected to heat stress had reduced average daily gain (ADG) and average daily feed intake (ADFI); a higher heterophil level and heterophil-to-lymphocyte ratio, and a lower lymphocyte level; upregulated mRNA expression of 70 kDa heat shock protein (HSP70) levels in heart, kidney, and breast muscle; and shorter jejunal villus height, deeper crypt depth, and a lower ratio of villus-height-to-crypt-depth compared with those broilers raised in thermoneutral conditions. Supplemental BG increased ADG, jejunal villus height, and the villus-height-to-crypt-depth ratio and decreased the feed-to-gain ratio and creatine kinase and lactate dehydrogenase levels in breast muscle compared with the birds who received control diets. The inclusion of BG in diets significantly decreased the mRNA expression of HSP70 levels in heart, kidney, and breast muscle in birds subjected to heat challenge. These results indicate that the BG-supplemented diet was effective in partially ameliorating adverse effects in resistance to heat stress in broiler chickens.

Effects of feeding Bacillus subtilis to heat stressed broiler chickens with or without an antibiotic growth promoter

The effects of feeding probiotic (PB) with or without Lincomycin 2.2% (AGP) were investigated in broiler chickens during summer. Seven hundred Cobb-500 one day old straight run broiler chicks were randomly distributed into four dietary treatments each of five replications. Four diets were compared: control; control diet plus PB (Bacillus subtilis DSM17299) at a level of 50g/100kg; control plus (AGP) at a level of 15g/100kg and control plus a combination of PB and AGP (50gm/100kg and 15g/100kg respectively). Control birds were fed on a corn-soybean based starter mash that contained ME 3000 kcal/kg and CP 24.39% from 0-21 days of age and a corn-soybean based grower mash of ME 3100 kcal/kg and CP 20.43% during 22-35 days of age. The records were kept of feed intake (FI), body weight and mortality while weight gain, feed conversion ratio (FCR) and survivability were calculated. Temperature and humidity were recorded four times daily except during extreme heat stress when measurements were made more frequently. One bird that was close to average of pen weight was taken from each replication at the end of the trial and the birds were sacrificed to determine carcass characteristics. Both performance and carcass yield data were statistically analyzed. Birds that received PB and a combination of PB +AGP treatments showed significant differences (P<0.01) from control with respect to body weight gain and FCR while feeding AGP alone although showed a decrease in feed intake. Abdominal fat was significantly (P<0.01) reduced in PB treated birds. Higher mortality was encountered in control group. Both PB alone and a combination of AGP treatments were able to show improved performance and reduced mortality, feeding PB alone may be practiced on the combined grounds of improved performance, efficiency in combating heat stress and to discourage the use of AGP in broiler diet.Asian J. Med. Biol. Res. June 2015, 1(1): 80-88

Mortality, production performance, water intake and organ weight of the heat stressed broiler chicken given savory (Satureja khuzistanica) essential oils through drinking water

An experiment was conducted to examine the effects on mortality, production performance, water intake (WI) and organ weight of Satureja khuzistanica essential oil (SkEO) using 720 one-day-old Arian broiler chicks in a 42-day trial. Experimental treatments were addition of 0 (control−), 200, 300, 400 and 500 mg/L SkEO or 500 mg/L polysorbate-80 (control+) into drinking water. The birds were kept under natural ambient temperatures 4–6°C above standard recommendation from days 22 to 42 of age. Addition of SkEO into drinking water at 200 and 500 mg/L decreased weight gain (P < 0.05) of the birds from days 29 to 35 of age with no differences in feed intake (FI) and feed conversion ratio (FCR) compared to control groups (P > 0.05). Addition of 300 and 500 mg/L SkEO into water increased mortality rate of the birds mainly from days 29 to 42 of age. The calculated European broiler index was greater for the birds receiving drinking water supplemented with 400 mg/L of SkEO compared with the other birds. In conclusion, administration of SkEO at 400 mg/L through drinking water to heat stressed broiler chickens may result in improved production performance efficiency.

Effects of corticosterone and dietary energy on immune function of broiler chickens.

An experiment was conducted to investigate the effects of dietary energy level on the performance and immune function of stressed broiler chickens (Gallus gallus domesticus). A total of 96 three-day-old male broiler chickens (Ross × Ross) were divided into two groups. One group received a high energy (HE) diet and the other group received a low energy (LE) diet for 7 days. At 5 days of age, the chickens from each group were further divided into two sub-groups and received one of the following two treatments for 3 days: (1) subcutaneous injection of corticosterone, twice per day (CORT group; 2 mg of CORT/kg BW in corn oil) and (2) subcutaneous injection of corn oil, twice per day (Control/Sham treatment group). At 10 days of age, samples of blood, duodenum, jejunum, and ileum were obtained. Compared with the other three groups, the LE group treated with CORT had the lowest average daily gain (ADG) and the poorest feed conversion ratio (FCR, P < 0.05). Furthermore, CORT treatment decreased the relative weight (RW) of the bursa independent of the dietary energy level, but it decreased the RW of the thymus only in the chickens fed the LE diet. By contrast, CORT administration decreased the RW of the spleen only in the chickens fed the HE diet (P < 0.05). The plasma total protein, albumin, tumor necrosis factor alpha, interleukin 2 and immunoglobulin G (IgG) levels were affected by the CORT treatment (P < 0.05); however, these factors were not significantly affected by the dietary energy level. Toll-like receptor-5 mRNA level was down-regulated by CORT injection in the duodenum and ileum (P < 0.05) and showed a trend of down-regulation in the jejunum (P=0.0846). The present study showed that CORT treatment induced immunosuppressive effects on the innate immune system of broiler chickens, which were ameliorated by consumption of higher dietary energy.

Behavioral changes and feathering score in heat stressed broiler chickens fed diets containing different levels of propolis

This experiment was conducted to evaluate the effects of dietary supplementation of green Brazilian propolis on behavioral patterns and feather condition of heat stressed broiler chickens. Five hundred and four (504) male Ross 708 broiler chicks at 15-day old were randomly allotted to six dietary treatments containing 0 (control), 100, 250, 500, 1000 and 3000mgkg−1 propolis, respectively. Each treatment consisted of four replicates of 21 birds each. Heat stress at 32°C was applied daily from 08:00 am to 17:00 pm from day 15–42. Twelve birds per treatment were randomly taken and marked with livestock color for behavioral observation. Treatment effects on behavioral patterns were recorded using direct observation instantaneous scan sampling technique. At the end of the experiment (42 days of age) the three birds used for behavioral observation were feather scored (from 1 to 5); while all birds (504) were individually scanned for primary feather abnormalities. The results indicated that the effects of using propolis as a feed additive for broilers reduced heat stress behavior, especially dietary treatment with 250 or 3000mgkg−1 propolis, by increasing bird walking activities and reducing panting behaviors (P<0.05, respectively). Moreover, 250mgkg−1 propolis (P<0.05) increased standing behavior also. Walking activities was also increased in the birds fed with 100mgkg−1 propolis (P<0.05). There were no significant (P>0.05) treatment effects on sitting, preening, feeding, drinking, wing elevations and feather pecking activities. Propolis at current doses did not significantly (P>0.05) improve feather scoring, but reduced (P=0.048) abnormal shape of primary feathers. The current results support that propolis treatment may be considered as a protective management practice in broiler chickens to alleviate the negative effects of heat stress, but further investigations may requested to determine the best type, dose, time and duration of its administration.

Concurrent supplementation of arginine and antioxidant vitamins E and C reduces oxidative stress in broiler chickens after a challenge withEimeriaspp.

Dominguez P.A., Pro-Martinez, A., Narciso-Gaytán, C., Hernández-Cázares, A., Sosa-Montes, E., Perez-Hernandez, P., Caldwell, D. and Ruiz-Feria, C. A. 2015. Concurrent supplementation of arginine and antioxidant vitamins E and C reduces oxidative stress in broiler chickens after a challenge with Eimeria spp. Can. J. Anim. Sci. 95: 143–153. Oxidation is a major problem associated with pathogen damage in animals. One-day-old mixed-sex broiler chicks (Cobb 500; n=624) were randomly assigned to one of six treatments: a basal diet [CTL; 40 mg of vitamin E (VE) kg−1of feed and 1.5% Arginine (Arg)] or the basal diet plus Arg (ARG; 0.3%), Arg+VE (AVE; 0.3% and 40 mg kg−1respectively), Arg+vitamin C (VC) (AVC; 0.3% and 1 g kg−1respectively), VE+VC (VEC; 40 mg+1 g kg−1respectively), or Arg+VE+VC (AVEC; 0.3%+40 mg+1 g kg−1respectively). At day 14, all birds were orally challenged with 100× the normal dose of Advent®coccidiosis vaccine (450 000 oocysts). Intestinal lesion scores (LS) in duodenum, jejunum and ceca were recorded, along with relative immune system organ weights at day 23. Plasma samples were taken before (2 h) and after challenge (12, 24 and 48 h) to determine malondialdehyde (MDA), nitric oxide (NO) and glutathione peroxidase activity (GPx). Birds fed the VEC diet were heavier at 7 d (P&lt;0.05) than birds fed the AVE diet. CTL birds had heavier (P&lt;0.05) bursas than AVC birds; no differences among treatments for spleen and thymus were found. The jejunum LS was lower in the AVC and VEC birds than in CTL birds, whereas ceca LS was highest in AVE birds, and the duodenum LS was not affected by treatment. Birds fed the AVEC diet had the lowest MDA levels before challenge, but higher levels of MDA than birds fed the CTL, ARG or AVE 12 h after challenge. Before challenge ARG birds had higher (P&lt;0.05) NO levels than AVEC-fed birds, but 12 h after challenge birds fed the CTL, ARG or AVE diet had lower NO levels than birds fed the AVC, VEC or AVEC diet. Before challenge AVEC-fed birds had higher (P&lt;0.001) GPx activity than CTL, ARG and AVE birds, but after 12, 24 and 48 h VEC birds showed higher GPx activity than CTL, ARG- and AVE-fed birds. Although Arg, VE and VC, modulated oxidative stress during coccidiosis challenge, the effects were not sufficient to affect performance relative to the control diet.

Various levels and forms of dietary α-lipoic acid in broiler chickens: Impact on blood biochemistry, stress response, liver enzymes, and antibody titers

The present experiment was conducted to evaluate the impact of various levels and forms of α-lipoic acid (ALA) on blood biochemistry, immune and stress response, and antibody titers in broiler chickens. The four levels (7.5, 15, 75, and 150 ppm) and 2 sources (powder, P-ALA and encapsulated, E-ALA) of ALA along with negative (C−) and positive control (C+; contains antibiotics) diets consisted of 10 dietary treatments, and these treatments were allocated to 1,200 1-d-old chicks and were replicated 12 times with 10 birds per replicate. Among the blood biochemistry parameters, creatinine levels were almost 3 times lower in E-ALA-supplemented diets compared to the C− diet (0.09 vs. 0.25 mg/dL; P < 0.0001). Neither level nor source of ALA affected blood urea nitrogen (BUN), total protein (TP), albumin, globulin, or albumin to globulin ratio (AGR). The supplemented diets decreased serum levels of the liver enzymes aspartate-aminotransferase (AST; P < 0.006) and alanine-aminotransferase (ALT; P < 0.0003). The Newcastle disease virus (NDV) antibody response in supplemented groups was poor at day zero (P < 0.0001) but increased by d 14 (P < 0.03). Birds did not respond to infectious bronchitis virus (IBV) vaccination at any observed stage (P > 0.05). The concentration of cortisol was reduced in chickens fed ALA-supplemented diets as compared to the C− diet (P < 0.001). Results suggest that ALA-supplemented diets ameliorated blood biochemistry profiles and immune responses and reduced stress in broiler chickens. The encapsulated form of ALA was more effective than the powder form.

Effects of Withania coagulans fruit powder and vitamin C on growth performance and some blood components in heat stressed broiler chickens

This study was conducted to study the effect of Withania coagulans (WC) fruit powder and vitamin C (VC) on growth performance and some blood components in heat stressed broilers. The experiment was conducted as a 2×3 factorial arrangement of treatments with 2 concentrations of VC (0 and 250mg/kg of diet) and 3 concentrations of WC (0, 2.5, and 5g/kg of diet). Each of 6 dietary treatments was fed to 4 replicate pens (9 broiler chickens/pen) from 25 to 42d of age. The house temperature was set at 34°C±2 (from 0900 to 1700h) throughout the experiment. Feed intake (FI), body weight gain (BWG), and feed to gain ratio (F:G) were calculated at the end of the experiment. At d 42 of age, the blood samples were collected from 1 broiler chicken per pen, and glucose and cholesterol concentrations, white blood cell (WBC) count, and activity of glutathione peroxidase (GPX) were determined. The FI and BWG increased by 5.5% and 12.7%, respectively, and F:G decreased by 6.5% with VC supplementation (P≤0.01). As dietary inclusion of WC increased from 0 to 5g/kg, both FI and BWG increased by 5.6% (linear, P≤0.023). The activity of GPX increased (P≤0.05) by 20.57% with addition of VC to the diet, whereas no effect of WC was observed. Neither VC nor WC had effect on blood cholesterol and glucose concentrations, WBC counts, relative weight of bursa of Fabricius, spleen, and liver, and relative length of the duodenum, jejunum, and ileum. It is concluded that dietary supplementation of 250mg VC/kg or 5g WC fruit powder/kg improved the growth performance of heat stressed broiler chickens.

Bioquímica sanguínea y concentración plasmática de corticosterona en pollo de engorde bajo estrés calórico

Las altas temperaturas ambientales propician susceptibilidad al estrés calórico en los pollos de engorde, lo que genera cambios metabólicos. Se buscó determinar los cambios en la bioquímica sanguínea y la concentración plasmática de corticosterona del pollo de engorde sometido a estrés calórico crónico y a las condiciones de temperatura ambiental del piedemonte amazónico colombiano, sobre las concentraciones plasmáticas de corticosterona, glucosa, proteínas totales, albumina, globulina, sodio, cloro, potasio, magnesio, fósforo y calcio. Se utilizaron pollos machos de 2 estirpes de 21 días de edad, distribuidos en un diseño experimental irrestrictamente al azar, en un esquema bifactorial, con 4 tratamientos. Se hicieron 5 repeticiones por tratamiento y 25 animales por unidad experimental. Las aves fueron alimentadas con una dieta básica de maíz y torta de soya con 3,100 Kcal de EM y 19,5 % de proteína hasta los 42 días de edad. El factor estirpe no tuvo efecto en las variables evaluadas (p ≥ 0,05). No obstante, existió diferencia estadística significativa (p ≤ 0,05) en todas las variables evaluadas al ser comparadas las concentraciones de los metabolitos de las aves en condiciones de estrés calórico crónico con las de las aves expuestas a las condiciones de temperatura del piedemonte amazónico colombiano. Se concluyó que la bioquímica sanguínea sufrió modificaciones significativas bajo las 2 temperaturas experimentales, con mayor detrimento fisiológico de las aves con estrés calórico crónico. La concentración de corticosterona se constituyó en el indicador más sensible y constante de la condición fisiológica de estrés crónico por calor.

Correction: Single and Combined Effects of Deoxynivalenol Mycotoxin and a Microbial Feed Additive on Lymphocyte DNA Damage and Oxidative Stress in Broiler Chickens

Correction: Single and Combined Effects of Deoxynivalenol Mycotoxin and a Microbial Feed Additive on Lymphocyte DNA Damage and Oxidative Stress in Broiler Chickens

Effects of Fusarium mycotoxins with yeast cell wall absorbent on hematology, serum biochemistry, and oxidative stress in broiler chickens

The objectives of the present study were to investigate the toxicity of feed-borne Fusarium mycotoxins on hematology, serum biochemistry, and oxidative stress of broiler chickens, and to evaluate the efficacy of yeast cell wall adsorbent (YCW) in preventing mycotoxins-induced adverse effects. A total of 300 one-day-old Arbor Acres broiler chickens (mixed sex) were randomly divided into 3 groups and received different treatments (5 repetitions per treatment). Treatments were control, naturally contaminated diet (NCD; aflatoxin, 102.08 mg/kg; zearalenone, 281.92 mg/kg; fumonisin, 5,874.38 mg/kg; deoxynivalenol, 2,038.96 mg/kg), and NCD + 2 g/kg of YCW. Broilers fed NCD showed elevated serum alanine transaminase, aspartate transaminase, alkaline phosphatase, γ-glutamyl transferase (GGT), and malondialdehyde (MDA) at 21 d, and alanine transaminase, GGT, creatine kinase, and MDA at 42 d. Higher white blood cell, lymphocyte (LYM), platelet, red blood cell, hemoglobin, hematocrit, and mean corpuscular hemoglobin counts at 21 d, as well as LYM in whole blood and hepatic mRNA expression of heat shock protein 70 at 42 d were also observed in broilers fed with NCD compared with the control diet. However, lower mean corpuscular volume at 42 d and total superoxide dismutase (T-SOD) at both 21 and 42 d were observed in broilers with the NCD treatment when compared with those with the control treatment. Dietary addition of YCW at the level of 2 g/kg in addition to the NCD treatment showed a positive protective effect on GGT, T-SOD in serum, white blood cells, LYM, platelets, and hemoglobin in whole blood at 21 d, and T-SOD, MDA in serum, LYM, mean corpuscular volume in whole blood, and hepatic mRNA expression of heat-shock protein 70 at 42 d. It is suggested that feeding NCD for 42 d might result in a deleterious effect on broiler chickens, and addition of 2 g/kg of YCW can partly attenuate the detrimental effects of the NCD feeding.

Single and Combined Effects of Deoxynivalenol Mycotoxin and a Microbial Feed Additive on Lymphocyte DNA Damage and Oxidative Stress in Broiler Chickens

The immune and intestinal epithelial cells are particularly sensitive to the toxic effects of deoxynivalenol (DON). The aim of this experiment was to study the effects of DON and/or a microbial feed additive on the DNA damage of blood lymphocytes and on the level of thiobarbituric acid reactive substance (TBARS) as an indicator of lipid peroxidation and oxidative stress in broilers. A total of forty 1-d-old broiler chicks were randomly assigned to 1 of 4 dietary treatments (10 birds per group) for 5 wk. The dietary treatments were 1) basal diet; 2) basal diet contaminated with 10 mg DON/kg feed; 3) basal diet contaminated with 10 mg DON/kg feed and supplemented with 2.5 kg/ton of feed of Mycofix Select; 4) basal diet supplemented with Mycofix Select (2.5 kg/ton of feed). At the end of the feeding trial, blood were collected for measuring the level of lymphocyte DNA damage of blood and the TBARS level was measured in plasma, heart, kidney, duodenum and jejunum. The dietary exposure of DON caused a significant increase (P = 0.001) of DNA damage in blood lymphocytes (31.99±0.89%) as indicated in the tail of comet assay. Interestingly addition of Mycofix Select to DON contaminated diet decreased (P = 0.001) the DNA damage (19.82±1.75%) induced by DON. In order to clarify the involvement of lipid peroxidation in the DNA damage of DON, TBARS levels was measured. A significant increase (P = 0.001) in the level of TBARS (23±2 nmol/mg) was observed in the jejunal tissue suggesting that the lipid peroxidation might be involved in the DNA damage. The results indicate that DON is cytotoxic and genotoxic to the chicken intestinal and immune cells and the feed additive have potential ability to prevent DNA damage induced by DON.

Effects of Turmeric Rhizome Powder and Oil Sources on Performance, Immune System and Bone Characteristics in Pre and Post Heat Stressed Broiler Chickens

Aims: The objective of this study was to evaluate the effects of dietary Turmeric Rhizome powder (TRP) as a natural antioxidant and soybean (SO), canola oil (CO) and tallow (T) on performance, immune system, relative weight of organs and bone quality in 28d and post heat stressed broilers. Study Design: The experiment was done in completely randomized design with 3×3 factorial arrangement. Place and Duration of Study: Sample: Department of Animal Science, between July 2010 and September 2011. Methodology: 792 day-old broilers were randomly allotted to a 3×3 factorial arrangement with three levels of TRP (0, 0.4 and 0.8%) and three oil sources of canola and soybean oil and tallow. Heat stress (33±1oC) was applied from 10:30 to 15:30 of every day for all birds from 28-42d.

비타민 C 및 E의 첨가 급여가 육계의 소포체 스트레스와 지방 및 포도당 대사 연관 유전자의 발현에 미치는 영향

본 연구는 육계에서 비타민 C와 E의 첨가 급여가 소포체(ER) 스트레스 및 지방 및 포도당대사 연관 유전자들의 발현에 미치는 영향을 살펴보고자 실시하였다. 육계에 비타민 첨가 급여 후 5주령에 닭의 간을 취하여 유전자들의 발현을 real-time PCR로 비교 분석하였다. 육계의 비타민 C 및 E 첨가 급여는 HSP70, HSP90 및 HMGCR 스트레스 마커 유전자들의 발현을 감소시켰다. ER 스트레스 관련 유전자들 또한 스트레스 마커 유전자들과 마찬가지로 비타민 처리에 의하여 대조구에 비하여 낮은 발현 양상을 보여줌으로서, 대표적 스트레스 마커 유전자들과 더불어 세포 내 ER stress도 영향을 받을 수 있음을 보여 주었다. 육계의 비타민 첨가 급여는 대조구에 비하여 지방대사 연관 유전자들의 발현이 비타민 첨가구에서 감소함에 따라 지방대사에도 영향을 미치고 있음을 보여주었다. 비타민의 첨가 유무와 관계없이 간세포 내부로 포도당을 운반하는 운반체인 GLUT 단백질들의 발현에는 큰 영향을 주지 못하였다. 본 연구의 결과는 육계에 사료 내 비타민 C 또는 E의 첨가급여가 닭의 스트레스 정도를 완화시킬 수 있으며, 또한 지방합성 대사에도 영향을 미칠 수 있음을 세포 수준의 관련 유전자들의 분석을 이용하여 검증할 수 있음을 보여 주었다. This study was conducted to evaluate the effects of dietary supplementation of vitamin C or E on the expressions of endoplasmic reticulum (ER) stress, lipid and glucose metabolism associated genes in broiler chickens. A total of 216 one-day-old male broilers was randomly alloted to 4 treatments with 6 replicate pens per treatment and 9 broilers per pen for 35 days. The dietary treatments were control, vitamin C (control diet + ascorbic acid 200 mg/kg diet), vitamin E (control diet + <TEX>${\alpha}$</TEX>-tocopherol 100 mg/kg diet), vitamin C + E (control diet + vitamin C 200 mg/kg + vitamin E 100 mg/kg), respectively. To evaluate gene expressions by quantitative real-time polymerase chain reaction, total RNA was extracted from the liver of the chicken at 35 days of age. Dietary supplementation of vitamins was significantly down-regulated the expression of stress marker genes including HSP70, HSP90, and HMGCR, as compared to the control (p<0.05). The expressions of ER stress associated genes also inhibited by supplementation of vitamins as well (p<0.05). Vitamin C supplementation suppressed the expression of lipid associated genes such as FASN, FATP1 and ACSL1. Vitamin supplementation did not affect the glucose transporters, GLUT2 and GLUT8, in the liver. The results of the present study indicated that dietary supplementation of vitamin C or E could be beneficial for the alleviating physiological stress in broiler chickens.

Effect of dietary vitamin E on Eimeria tenella-induced oxidative stress in broiler chickens

An experiment was carried out to investigate the impact of high doses of dietary vitamin E on antioxidant status in broiler chickens (Ross 308) experimentally infected with Eimeria tenella . One day old chicks were assigned to five groups (25 each) and given basal diet (A and B) or basal diet supplemented with 100, 316 or 562 mg/kg of vitamin E (C to E), respectively. On the 21st day, all chicks except those in group A were inoculated with E. tenella and monitored for any change in blood vitamin E, malondialdehyde (MDA) and superoxide dismutase (SOD). Plasma vitamin E decreased by infection, but increased with dietary vitamin E (p 0.05), but it was significantly higher in group D than in groups B and E (p<0.05). In conclusion, addition of dietary vitamin E at 316 mg/kg can afford antioxidant protection to chickens infected with E. tenella , but at higher doses it may aggravate the unbalanced oxidant/antioxidant status. Key words : Eimeria tenella, oxidative stress, broiler chickens, vitamin E, malondialdehyde, superoxide dismutase.

Effect of copper on antioxidant ability and nutrient metabolism in broiler chickens stimulated by lipopolysaccharides

The aim of the experiment was to investigate the interaction between Cu intake, inflammatory challenge and oxidative stress in broiler chickens. Furthermore, it was tested whether plasma ceruloplasmin (Cp) could be a sensible parameter for dietary Cu. One hundred forty-four day old chickens were raised on a basal control diet without added copper (Group Cu-6.5, basal Cu content 6.5 mg/kg diet) or a diet supplemented with Cu at 8 or 50 mg/kg (Groups Cu-14.5 and Cu-56.5, respectively) with four replicates of 12 animals for each treatment. Starting on day 21, chickens were injected intraperitoneally with lipopolysaccharides (LPS) once a day for 3 days. Before this challenge, Group Cu-14.5 had the lowest gain and the feed to gain ratio was the highest. After injection of LPS, however, chickens of Group Cu-14.5 had the best zoo-technical performance. For chickens of Group Cu-6.5, LPS injection resulted in elevated rectal temperature, and lower erythrocyte superoxide dismutase (CuZn-SOD) activity, compared with the other groups. LPS injection increased plasma uric acid in Group Cu-6.5 significantly, but was without influence in Group Cu-56.5. At all Cu-levels, LPS injection increased erythrocyte CuZn-SOD activity and decreased thiobarbituric acid reacting substances. No significant difference in plasma Cp was found in chickens fed different dietary Cu. LPS injection significantly increased plasma Cp in Group Cu-56.5. The results suggest that varying dietary Cu levels seem to modulate the parameters involved in immunological responses and oxidant stress and that plasma Cp is not a reliable parameter for dietaryCu.

The effect of glucagon-like peptide 2 injection on performance, small intestinal morphology, and nutrient transporter expression of stressed broiler chickens

An experiment was conducted to determine the effect of injecting glucagon-like peptide 2 (GLP-2) on the small intestinal weight, morphology, and nutrient transporter expression in pharmacologically stressed broiler chickens. A total of 144 seven-day-old birds were fed either a basal diet (CTRL) or a basal diet plus 30 mg of corticosterone (CORT)/kg of diet for a total of 14 d. Half of the birds from each group were injected daily with GLP-2 (6.7 nmol/kg of BW) or saline for 14 d. The average final BW, ADG, ADFI, and the ratio of feed intake to weight gain (F:G) was recorded over 21 d for the 4 groups of 36 birds, namely CTRL + saline, CTRL + GLP-2, CORT + saline, and CORT + GLP-2. In addition, the absolute and relative small intestinal weight, villus height (VH), and crypt depth (CD) of the duodenum and jejunum, as well as the abundance of sodium and glucose co-transporter 1 (SGLT-1), vitamin D-dependent calcium-binding protein-28,000 molecular weight (CaBP-D28k), and peptide transporter 1 (PepT-1) mRNA in the duodenum and of liver fatty acid-binding protein (L-FABP) mRNA in the jejunum. The total DNA, RNA, and protein content in small intestinal mucosa were also determined. The results showed that CORT administration significantly lowered average final BW, ADG, ADFI, absolute small intestinal weight, VH, and CD of duodenum and jejunum (P < 0.05) while increasing the relative small intestinal weight, F:G, relative abundance of SGLT-1, CaBP-D28k, PepT-1, and L-FABP mRNA (P < 0.05). Glucagon-like peptide 2 injection increased the average final BW, ADG, VH, and CD in duodenum and jejunum and relative abundance of SGLT-1, CaBP-28k, PepT1, and PepT1 mRNA of broiler chickens, respectively (P < 0.05), and decreased F:G (P < 0.05). In chickens fed basal diet plus CORT, injecting GLP-2 decreased F:G (P < 0.05); increased VH and CD of duodenum and CD of jejunum; and increased relative abundance of SGLT-1, CaBP-D28k, PepT-1, and L-FABP mRNA, RNA, and total protein content in small intestine compared with the injection of saline (P < 0.05). In birds fed the basal diet, GLP-2 injection decreased F:G (P < 0.05) and increased final BW, ADG, small bowel weight, CD of jejunum, and relative abundance of CaBP-D28k and PepT-1 mRNA compared with injecting saline (P < 0.05). In conclusion, GLP-2 injection reversed the negative effect of stress on the weight and morphology and the absorptive function of small bowel of broiler chickens. Glucagon-like peptide 2 injection also had a positive effect on the growth performance of healthy broiler chickens.

Effects of different acute high ambient temperatures on function of hepatic mitochondrial respiration, antioxidative enzymes, and oxidative injury in broiler chickens

This study investigated the effects of different acute high ambient temperatures on dysfunction of hepatic mitochondrial respiration, the antioxidative enzyme system, and oxidative injury in broiler chickens. One hundred twenty-eight 6-wk-old broiler chickens were assigned randomly to 4 groups and subsequently exposed to 25 (control), 32, 35, and 38 degrees C (RH, 70 +/- 5%) for 3 h, respectively. The rectal temperatures, activity of antioxidative enzymes (superoxide dismutase, catalase, and glutathione peroxidase), content of malondialdehyde and protein carbonyl, and the activity of mitochondrial respiratory enzymes were determined. The results showed that exposure to high ambient temperature induced a significant elevation of rectal temperature, antioxidative enzyme activity, and formation of malondialdehyde and protein carbonyl, as well as dysfunction of the mitochondrial respiratory chain in comparison with control (P < 0.05). Almost all of the indicators changed in a temperature-dependent manner with the gradual increase of ambient temperature from 32 to 38 degrees C; differences in each parameter (except catalase) among the groups exposed to different high ambient temperatures were also statistically significant (P < 0.05). The results of the present study suggest that, in the broiler chicken model used here, acute exposure to high temperatures may depress the activity of the mitochondrial respiratory chain. This inactivation results subsequently in overproduction of reactive oxygen species, which ultimately results in oxidative injury. However, this hypothesis needs to be evaluated more rigorously in future studies. It has also been shown that, with the gradual increase in temperature, the oxidative injury induced by heat stress in broiler chickens becomes increasingly severe, and this stress response presents in a temperature-dependent manner in the temperature range of 32 to 38 degrees C.