Effects of thermo-resistant non-starch polysaccharide degrading multi-enzyme on growth performance, meat quality, relative weights of body organs and blood profile in broiler chickens.

This research was conducted to study the performance and carcass parameters of broiler chickens fed diets supplemented with heat-treated non-starch polysaccharide degrading enzyme. A total of 432 one-day old Ross 308 broiler chickens were allocated to five treatments: (i) CON (basal diet), (ii) E1: CON + 0.05% multi-enzyme, (iii) E2: CON + 0.1% multi-enzyme, (iv) E3: CON + 0.05% thermo-resistant multi-enzyme and (v) E4: CON + 0.1% thermo-resistant multi-enzyme, each treatment consisted of six replications and 12 chickens in each replication. The chickens were housed in three floor battery cages during 28-day experimental period. On days 1-7, gain in body weight (BWG) improved by feeding the diets supplemented with thermo-resistant multi-enzyme. On days 7-21 and 1-28, chickens fed the diets containing thermo-resistant multi-enzyme showed improved (p < 0.05) BWG and feed conversion ratio (FCR) compared to CON group. Supplementing the diets with multi-enzyme or thermo-resistant multi-enzyme affected the percentage of drip loss on d 1 (p < 0.05). Drip loss percentage on days 3 and 5 and also meat colour were not affected significantly. Supplementing the diets with multi-enzyme or thermo-resistant multi-enzyme did not affect the relative weights of organs but compared to CON group, relative weight of breast muscle increased and abdominal fat decreased (p < 0.05). Among measured blood constituents, chickens fed supplemented diets with thermo-resistant multi-enzyme showed higher (p < 0.05) IgG. Counts of red and white blood cells and lymphocyte percentage were not affected. In conclusion, the results demonstrated that supplementing pelleted diets with thermo-resistant multi-enzyme improved performance of broiler chickens.

Effects of lactulose supplementation on performance, blood profiles, excreta microbial shedding of Lactobacillus and Escherichia coli, relative organ weight and excreta noxious gas contents in broilers.

This study was to evaluate the effects of lactulose supplementation on performance, blood profiles, excreta microbial shedding of Lactobacillus and Escherichia coli, relative organ weight and excreta noxious gas contents in broilers. A total of 720 ROSS 308 broilers with a body weight of 46 ± 0.1 g (1 day of age) were used in a 28-d experiment. Broilers were randomly allotted to 4 experiment diets with 12 replicate pens and 15 birds per pen. Dietary treatments were as follows: NC, negative control (without antibiotic); PC, NC + 0.1% tiamulin; L1, NC + 0.1% lactulose; and L2, NC + 0.2% lactulose. Broilers were fed with phase 1 (1-8 day), phase 2 (9-18 day) and phase 3 (19-28 day) diets in the form of mash. During day 1-8, broilers fed the PC and L2 diets had higher (p < 0.05) body weight gain than those fed the NC diet. During day 19-28, broilers fed the L1 and L2 diets had lower (p < 0.05) feed intake than those fed the NC diet. The feed conversion ratio (FCR) was decreased (p < 0.05) in L1 treatment compared with NC treatment. Overall, the FCR was improved (p < 0.05) in all supplementation treatments compared with NC treatment. The apparently metabolizable nitrogen in L1 treatment was higher (p < 0.05) than that in NC treatment at day 28. The excreta Lactobacillus was increased and E. coli was decreased in PC and L2 treatments compared with NC treatment at day 28 (p < 0.05). The excreta NH3, H2S and acetic acid contents were decreased (p < 0.05) in L1 and L2 treatments compared with NC treatment. The relative weight of abdominal fat of broilers fed the PC diet was lowest (p < 0.05) compared with other treatments. In conclusion, this study indicated that dietary supplementation of 0.1% or 0.2% lactulose could improve growth performance, decrease excreta E. coli and excreta NH3 and H2S contents.

Effect of dietary levan fructan supplementation on growth performance, meat quality, relative organ weight, cecal microflora, and excreta noxious gas emission in broilers.

A total of 720 1-d-old male Ross broilers (BW of 48.0±0.3 g) were used to evaluate the effects of dietary levan fructan supplementation on growth performance, meat quality, relative organ weight, cecal microflora, and excreta noxious gas emission in broilers. This experiment lasted 31 d. Broilers were randomly allotted to 1 of 3 dietary treatments: 1) CON, basal diet, 2) CON+0.25% fructan (FC1), and 3) CON+0.50% fructan (FC2). Each treatment contained 16 pens with 15 chicks per pen. Broilers on levan fructan supplementation treatments (FC1+FC2) had a lower (P=0.005 for d 15 to 31) ADFI and greater (P=0.005 for d 15 to 31 and P=0.022 for d 1 to 31) G:F than those on the CON. A decreased (P=0.031) relative spleen weight was observed with levan fructan supplementation treatments compared with the CON. Cecal E. coli and C. perfringens concentrations in levan fructan treatments were decreased, while cecal Lactobacillus, as well as Bifidobacteria, concentrations in levan fructan treatments were increased compared with the CON. However, excreta NH3 concentrations were decreased (P=0.013) in levan fructan treatments compared with the CON. In conclusion, fructan supplementation improved later stage growth performance, increased cecal Lactobacillus and Bifidobacteria concentrations, and decreased cecal E. coli and C. perfringens concentrations, as well as excreta NH3 concentrations, in broilers.

Effects of chitooligosaccharide supplementation on performance, blood characteristics, relative organ weight, and meat quality in broiler chickens.

This study was conducted to evaluate the effects of dietary supplementation with chitooligosaccharide (COS) on growth performance, blood characteristics, relative organ weight, and meat quality in broilers. A total of 480 broilers with an average initial BW of 45.04 g per chick were randomly allocated into 1 of the following 4 dietary treatments (20 broilers per pen with 6 pens per treatment): 1) CON (basal diet), 2) ANT (basal diet + 44 mg/kg of avilamycin), 3) COS0.2 (basal diet + 14 g/kg of COS), 4) COS0.4 (basal diet + 28 g/kg of COS). The experiment lasted for 5 wk and avilamycin was administered from d 0 to 21. Growth performance was measured on d 0, 21, and 35, and all other response criteria were measured on d 35. No change in feed conversion (G:F) was observed in response to any of the treatments throughout the experimental period (P > 0.05). However, BW gain and feed intake were greater (P < 0.05) in broilers provided with feed supplemented with COS than in those in the control group. In addition, broilers had significantly greater (P < 0.05) red blood cell and high-density lipoprotein cholesterol concentrations when they were provided with the COS0.4 diet, whereas the triglyceride concentration was lower (P < 0.05) in broilers in the COS0.2 treatment group. No other blood characteristics were affected by the treatments. Additionally, as the dietary COS concentration increased, the liver weight increased (P < 0.05). Conversely, as the concentrations of dietary COS increased, abdominal fat decreased (P < 0.05). Furthermore, meat yellowness decreased (P < 0.05) as the concentration of COS increased. Finally, the breast meat and abdominal fat of birds provided with feed supplemented with COS had a lower (P < 0.05) saturated fatty acid concentration but a greater concentration of total monounsaturated fatty acids (P < 0.05) than that of birds in the control. In conclusion, COS can improve the performance and breast meat quality of broilers while increasing the red blood cell and high-density lipoprotein cholesterol concentrations in blood. In addition, COS can induce a decrease in abdominal fat and improve meat quality.

Poult performance as influenced by age of dam, genetic line, and dietary vitamin E.

An experiment was conducted to measure the effects of age of dam, genetic line, and dietary levels of vitamin E on growth and immunocompetence of poults. Age of dam was defined as younger (in early egg production) and older (past peak production); line consisted of a commercial sire and dam line; and dietary vitamin E was supplemented into the diet at 10 and 300 IU/kg of feed. Traits measured included body, liver, gizzard, and yolk sac weights at hatch; BW and feed conversion to 9, 28, and 42 d; response to SRBC, Phaseolus vulgaris agglutinin-P, and Escherichia coli administered at 28 d of age; and response to a cold stress on d 5 posthatch. Differences among genetic lines were evident with growth greater for poults from the sire than from the dam line. Performance of poults from older dams was generally superior to that of poults from younger dams. The higher level of vitamin E resulted in a greater than 7-fold increase in blood plasma vitamin E and reduced mortality. There were interactions among the main effects in which the fitness of poults from younger dams was enhanced by the higher level of vitamin E and the effect of breeder age differed among genetic lines.

Influence of method of whole wheat inclusion and xylanase supplementation on the performance, apparent metabolisable energy, digestive tract measurements and gut morphology of broilers.

1. The aim of the present study was to examine the influence of whole wheat inclusion and xylanase supplementation on the performance, apparent metabolisable energy (AME), digesta viscosity, and digestive tract measurements of broilers fed on wheat-based diets. The influence of the method of whole wheat inclusion (pre- or post-pelleting) was also compared. A 3 x 2 factorial arrangement of treatments was used with three diet forms (648 g/kg ground wheat [GW], GW replaced by 200 g/kg of whole wheat before [WW1] or after cold-pelleting [WW2]) and two xylanase levels (0 and 1000 XU/kg diet). 2. Birds given diets containing whole wheat had improved weight gains, feed efficiency and AME compared to those fed on diets containing ground wheat. The relative gizzard weight of birds fed WW2 diets was higher than in those fed GW and WW1 diets. Pre-pelleting inclusion of whole wheat had no effect on relative gizzard weight. Post-pelleting inclusion of whole wheat resulted in greater improvements in feed efficiency and AME than the pre-pelleting treatment. 3. Xylanase supplementation significantly improved weight gain, feed efficiency and AME, irrespective of the wheat form used. Viscosity of the digesta in the duodenum, jejunum and ileum were reduced by xylanase addition. Xylanase supplementation reduced the relative weight of the pancreas. 4. Neither xylanase supplementation nor whole wheat inclusion influenced the relative weight and length of the small intestine. 5. Xylanase supplementation increased ileal villus height. A significant interaction between diet form and xylanase was observed for ileal crypt depth. Xylanase supplementation had no effect on crypt depth in birds fed on diets containing GW, but increased the crypt depth in WW2 diets. No significant effects of diet form and xylanase supplementation were observed for the thickness of the tunica muscularis layer of gizzard or villus height, crypt depth, goblet cell numbers or epithelial thickness in the ileum. 6. Improved performance observed with post-pelleting inclusion of whole wheat was associated with increased size of the gizzard and improved AME. The gizzard development hypothesis, however, will not explain the improvements observed with pre-pelleting inclusion of whole wheat, suggesting the involvement of other factors.

Free diet selection by broilers as influenced by dietary macronutrient ratio and corticosterone supplementation. 1. Diet selection, organ weights, and plasma metabolites.

Male broiler chickens (aged 21 d) were allowed to chose freely for 14 d between three diets in which only one specific macronutrient (protein, lipid, or carbohydrate) was isocalorically substituted for one other macronutrient, but otherwise (nearly) isocaloric and composed of the same ingredients. The three diets were low protein (LowCP; 15.81% CP; 6.56% lipid; 50.78% carbohydrate), low lipid (LowL; 19.63% CP; 3.01% lipid; 51.12% carbohydrate), and low carbohydrate (LowCHO; 19.50% CP; 7.72% lipid; 44.00% carbohydrate). The chickens either received 0, 30, or 45 mg of corticosterone (CORT) per kg diet. As a percentage of their total intake, unsupplemented chickens consumed 24.0, 71.4, and 4.6% of the LowCP, LowL, and LowCHO diets, respectively, giving a total CP, L, and CHO intake of 282, 61, and 765 g, respectively. The addition of CORT significantly changed the diet selection, as compared to the unsupplemented chickens, CORT chickens consumed a greater percentage from the LowCP (35%), less from the LowL (55%), and again more from the Low-CHO (10%) diet. On the other hand, total feed consumption, macronutrient, and ME intake were not altered significantly by CORT supplementation, probably because of the close similarity of the diets. Corticosterone-supplemented chickens manifested hyperglycemia, hyperlipidemia, and uric acidemia suggesting insulin resistance, increased lipogenesis and protein catabolism, respectively. The elevated plasma creatine kinase (CK) activities of CORT chickens are also suggestive for decreased muscle cell membrane stability. Furthermore, CORT chickens were characterized by increased proportional weights of liver, abdominal fat pad, proventriculus, and gizzard, whereas an involution of spleen and bursa was observed. In conclusion, the present results suggest that high circulating levels of CORT as in the case of stress results in metabolic alterations, which in turn, affects diet preference as a compensatory mechanism to adapt energy and nutrient metabolism.

Effects of inorganic adsorbents and cyclopiazonic acid in broiler chickens.

Previous studies with cyclopiazonic acid (CPA) have indicated that this mycotoxin strongly adsorbs onto the surface of a naturally acidic phyllosilicate clay (AC). The objective of this study was to determine whether AC (and similar adsorbents) could protect against the toxicity of CPA in vivo. Acidic phyllosilicate clay, neutral phyllosilicate clay (NC, or hydrated sodium calcium aluminosilicate), and a common zeolite (CZ, or clinoptilolite) were evaluated. One-day-old broiler chicks consumed diets containing 0 or 45 mg/kg CPA alone or in combination with 1% AC, NC, or CZ ad libitum from Day 1 to 21. Body weight, feed consumption, feed:gain, hematology, serum biochemical values, and enzyme activities were evaluated. Compared to controls, CPA alone reduced body weight at Day 21 by a total of 26% and resulted in a significantly higher feed:gain ratio. Toxicity of CPA was also expressed through increased relative weights of kidney, proventriculus, and gizzard. Also, there were some alterations in hematology, serum biochemical values, and enzyme activities. Treatment with inorganic adsorbents did not effectively diminish the growth-inhibitory effects of CPA or the increased weights of organs, although there was some protection from hematological, serum biochemical, and enzymatic changes produced by CPA. The results of this study suggest that in vitro binding of CPA to clay does not accurately forecast its efficacy in vivo; the reasons for this discrepancy are not clear, but they may be related to differences in clay binding capacity and ligand selectivity for CPA in vitro vs in vivo. Predictions about the ability of inorganic adsorbents to protect chickens from the adverse effects of mycotoxins should be approached with caution and should be confirmed in vivo, paying particular attention to the potential for nutrient interactions.

An attempt to distinguish between the direct and indirect effects, in the laying domestic fowl, of added dietary copper sulphate.

1. An experiment is reported in which the effects of giving copper sulphate-supplemented diets and control unsupplemented pair-fed diets to laying hens were compared. 2. The level of food intake significantly adversely affected mean body-weight, egg number, egg weight, liver, kidney, oviduct and ovary weights. Gizzard weight/kg body-weight was significantly increased both with decreasing levels of food intake and increased CuSO4 supplementation. 3. There was evidence of a depressing effect of CuSO4 per se on egg production and possibly on oviduct and ovary weight. 4. Liver lipid concentration was significantly decreased with decreasing levels of food intake and the results also suggest a depressing effect of CuSO4. 5. The Cu concentrations and total contents in liver and kidneys were significantly increased by dietary added CuSO4. Liver and kidney Zn and Fe concentrations were increased with decreasing levels of food intake rather than by CuSO4 addition.