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1.
The present experiment was conducted to investigate the effects of fiber and threonine (Thr) on growth performance, intestinal morphology and immune responses of broiler chickens. A total of 420 one-day-old mixed sex broiler chicks (Ross 308) were randomly divided into 6 experimental diets and 5 replicates of 14 chicks based on a factorial arrangement (2 × 3) from 1 to 42 d of age. Experimental factors included dietary supplemental fiber type (no supplemental fiber [NSF], 30 g/kg sugar beet pulp [SBP] or 30 g/kg rice hull [RH]) and Thr inclusion level (100% or 110% of Thr requirement recommended by breeder company [Ross 308]). Growth performance of broilers was assayed at different periods of the experiment. Intestinal morphometric features were measured at 21 d of age. Antibody titer against sheep red blood cells (SRBC), Newcastle and influenza disease viruses were measured on d 30 of trial. Dietary inclusion of SBP and RH significantly decreased feed intake and weight gain during the entire rearing period (P < 0.05). Interaction of fiber and Thr had no beneficial effects on the performance of chickens across the entire rearing phase. Dietary supplementation of 110% Thr required level improved jejunal morphometric features (P < 0.05), whereas its inclusion with fibrous materials failed to show the same effects. Dietary supplemental Thr together with SBP significantly increased antibody production against SRBC (P < 0.05). In conclusion, although supplemental 30 g/kg fibrous materials impaired growth performance, inclusion of SBP along with 110% Thr level improved the humoral immunity in broiler chickens.  相似文献   

2.
The experiment was carried out on 96 female broilers, allocated to eight groups of 12 birds kept in individual cages. Two basal wheat‐ and soyabean meal‐based diets containing 150 g/kg of rapeseed expeller cake were formulated, differing in the level of P: 7.1 g/kg in diet H or 5.9 g/kg in diet L. Rapeseed cake supplied 3.15 μmol alkenyl glucosinolates per gram of diet. The eight treatments were: basal diets only, basal diets + phytase (1000 U/kg), basal diets + organic acid blend (OA, 6 g/kg), or basal diets + both additives. Diets were fed from day 8 to 28 of life. The results showed that the lower dietary P content and OA supplementation did not significantly affect feed intake or BWG, while both increased (p < 0.001) after phytase supplementation. Tibia ash content as well as tibia ultimate strength were lower (p < 0.001) in birds fed diets L compared with diets H, and increased (p < 0.01) with phytase supplementation of diet L, while OA had no influence on either parameter. Dietary P levels and OA supplementation had no influence on the pH of gut digesta, but the pH of jejunal digesta increased following phytase supplementation (p < 0.01). Morphological measurements of the small intestinal mucosa of chicks indicated that OA added to diet L depressed villi height (p < 0.001) and crypt depth (p < 0.001); both parameters increased after phytase supplementation (p < 0.01). The lower total SCFA as well as acetic, propionic and butyric acid concentrations in caecal digesta indicated lower activity of caecal microflora in birds fed diets L compared with H. OA supplementation had no influence, while phytase supplementation increased the concentration of acetic acid in caecal digesta. Supplementation of diets with either phytase or OA increased thyroid weight by 16% (p < 0.01) and 11% (p < 0.05) respectively. The increase in thyroid weight because of phytase supplementation was greater at the lower dietary P level, and the greatest when both phytase and OA were added to the diet.  相似文献   

3.
Bone problems have been a key issue that perilously affects broilers' health and welfare, resulting in severe economic loss. The present study was aimed at investigating the influence of dietary rice hull silicon (RHS) on the performance, meat quality, and bone-breaking strength of broilers. One hundred 10-day-old Arbor Acres chicks were used in the study. The birds were divided into 5 groups: one group was kept as the control, and other groups were provided with 2.5, 5.0, 7.5, and 10.0 mg/kg dietary RHS along with their basal diets. Results showed that diets containing various levels of dietary RHS did not adversely affect (P > 0.05) the body weight, feed intake, and feed conversion ratio. Drip loss of thigh meat showed a reduced value in the group supplemented with 7.5 mg/kg dietary RHS compared with other groups (P < 0.05), and the lowest thawing loss was observed in the same group; however, it showed no significant difference among other groups. Similarly, thawing loss of breast meat tended to decrease in the dietary RHS groups and significantly decreased (P < 0.05) in the 7.5 mg/kg RHS group. The shear force of breast meat was higher in all RHS groups, and the highest was in the 7.5 mg/kg RHS group (P < 0.05). Although tibia breaking strength increased significantly (P < 0.05) in the 7.5 mg/kg RHS group (P < 0.05), but a significant difference in femur breaking strength was not found among groups. In conclusion, dietary RHS can be used as a natural mineral supplement for improving bone-breaking strength and reducing drip and thawing loss of breast and thigh muscles, particularly RHS at a level of 7.5 mg/kg in broiler diets.  相似文献   

4.
The interaction effect of whole wheat feeding and mannanoligosaccharides supplementation on growth performance, haematological indices and caecal microbiota of cockerel chicks were investigated using 250‐day‐old cockerel chicks previously reared for 7 days pre‐experimental period. Birds were fed with commercial chick mash during the pre‐experimental period. At the expiration of this period, 192 chicks were selected on weight equalization basis and assigned into 24 pens. Each treatment consisted of six pens, while each pen housed eight birds. Four wheat–soya bean‐based experimental diets were formulated in a 2 × 2 factorial arrangement of diets having two wheat forms (ground and whole wheat grain) each supplemented or not with 1 g/kg MOS/kg feed. Whole wheat feeding (irrespective of MOS supplementation) showed reduced (p < 0.05) feed intake. Birds fed whole wheat diet supplemented with MOS recorded the highest (p < 0.01) final live weight, weight gain and the best (p < 0.05) feed conversion ratio. Haemoglobin concentration, packed cell volume and red blood cell count of the chicks were not affected (p > 0.05) by dietary treatment. However, dietary supplementation with MOS resulted in increased (p < 0.05) WBC counts. The caecum content of chicks fed with MOS‐supplemented whole wheat diets recorded the least (p < 0.01) salmonella counts. In conclusion, combination of whole wheat feeding and MOS supplementation showed improved growth performance, gut microbiota and indications of improved health status of cockerel chicks.  相似文献   

5.
This experiment was conducted to investigate the effects of supplementation of probiotics and prebiotics on growth performance, nutrient digestibility, relative organ weight, fecal microbiota, blood profile, and excreta noxious gas emissions in broilers. A total of 714 one-day-old mixed sex ROSS 308 broilers with the initial BW = 40 ± 0.69 g was used in a 4-week trial. All birds were raised in wire cages. Birds were randomly allotted to 7 treatments with 6 replicates per treatment and 17 broilers per pen. Dietary treatments included: 1) T1 (control), 2) T2 [T1 + 0.2% probiotics (Bacillus sp. 1 × 109 CFU, Lactobacillus sp. 1 × 108 CFU, Aspergillus niger. 1 × 107 CFU)], 3) T3 (T1 + 1% chicory fiber), 4) T4 (T1 + 1% rice bran), 5) T5 (T1+ 0.2% probiotics + 1% chicory fiber), 6) T6 (T1 + 0.2% probiotics + 1% rice bran), and 7) T7 (T1 + 0.2% probiotics + 1% chicory fiber + 1% rice bran). During d 1 to 14, broilers fed the T5, T6, and T7 diets had greater body weight gain (BWG) compared with the T1 diet (P < 0.05). Moreover, probiotics-included treatments resulted in higher BWG compared with the probiotics-free diets (P < 0.05). Broilers fed the T7 diet increased more in BWG compared with those fed the T1 diet, whereas feed conversion ratio (FCR) decreased more in the T7 diet than the T1 diet overall (P < 0.05). Dry matter (DM) digestibility increased more in the T5, T6, and T7 diets compared with the T1 diet (P < 0.05). Broilers fed probiotics-based diets had more improved DM digestibility compared with those fed probiotics-free diets (P < 0.05). Excreta Lactobacillus counts increased more in the T7 diet compared with the T1 diet (P < 0.05). Broilers fed with probiotics diets had higher excreta Lactobacillus counts compared with those fed the probiotics-free diets (P < 0.05). In conclusion, supplementation with 0.2% probiotics and 1% dietary fiber as prebiotics could improve the growth performance, DM digestibility, and excreta Lactobacillus counts in broilers raised in wire cages.  相似文献   

6.
There is evidence to suggest that poultry may have a dietary requirement for metabolically available chromium (Cr) that exceeds the amount provided through wheat soybean meal diets. The objective of the present study was to investigate the effects of dietary supplemental organic Cr from Cr propionate at different dose levels (control = 0 μg/kg, T1 = 200 μg/kg, T2 = 400 μg/kg) on the growth performance, carcass traits, and meat quality of broilers. Weight gain and feed intake of each treatment were recorded at the start and after 14, 28 and 35 d, and feed conversion ratios (FCR) were calculated accordingly. At 35 d of age, birds were randomly selected and euthanized for carcass evaluation. Results of the first trial indicate that both Cr propionate treatments increased final body weight (P < 0.05), feed efficiency (P < 0.05) and body weight gain (P < 0.0001). Furthermore, Cr propionate supplementation improved (P < 0.0001) all carcass characteristics. Interestingly, with increased Cr dosage, carcass yield, dressing percentage and breast meat yield increased linearly (P < 0.0001). The second study reveals that the feed intake in the control group was significantly higher compared to both Cr propionate supplemented groups (T1 & T2). Furthermore, the Cr propionate supplemented T2 group displayed a significantly lower FCR than the control and T1 group (P = 0.027). Finally, Cr propionate supplementation increased the dressing percentage compared to control birds (P < 0.0001). In the third experiment, Cr propionate supplementation (T1 & T2) increased final body weight and decreased FCR compared with the control treatment. These effects were highly significant (P < 0.0001) throughout all feeding phases of the trial. Cr propionate supplementation also increased (P < 0.0001) carcass yield, dressing percentage, breast meat yield, leg and thigh weights compared with the control treatment. In conclusion, growth performance, feed conversion, carcass yield, breast and leg meats of broiler birds can be significantly improved by dietary inclusion of Cr propionate. Cr propionate can be supplemented to broiler birds from 1 d old of age at a level that provides 200 or 400 μg/kg organic Cr and can increase the efficiency of broiler production.  相似文献   

7.
An experiment was conducted with Arbor Acres broiler chickens that were fed 3 experimental diets—a control diet containing an adequate level of available phosphorus (AP) and 2 diets that were deficient in AP but supplemented with phytase at a level of either 500 or 750 phytase units/kg—to assess the effects of a novel microbial phytase supplement in broilers fed AP-deficient diets on growth performance and mineral utilization. Similar average daily gain, feed intake, and feed efficiency (P > 0.05) were obtained among broilers fed different diets. Compared with broilers fed the control diet, broilers fed diets with phytase had greater (P < 0.05) retention of Ca, P, and Zn. Moreover, the levels of Cu, Zn, Mg, and Mn in the tibia bone at 28 d of age, and Zn and Mn at 42 d of age in birds fed diets with phytase exceeded (P < 0.05) those of birds fed the control diet. Supplementation of phytase increased Zn and Mg contents in the plasma at 42 d of age. Birds responded similarly to phytase supplemented at a level of 500 or 750 phytase units/kg in terms of growth performance, mineral retention, and mineral content in the serum and bone. Therefore, with the supplementation of this novel phytase, it is possible to reduce the dietary levels of P and other minerals to below the recommended levels of the Feeding Standard of Chicken in P. R. China (ZB B 43005-86).  相似文献   

8.
A 42‐day feeding trial was conducted using 480‐day‐old, male Marshall broilers to study the utilization of unpeeled cassava root meal (UCRM) supplemented with or without 6 g/kg charcoal. The experimental design was laid out in a 3 × 2 factorial arrangement of treatments having three inclusion levels of UCRM (0, 100 and 200 g/kg) with or without 6 g/kg charcoal supplementation. Each treatment consisted of 80 birds replicated eight times with 10 birds per replicate. Main effect of inclusion level of UCRM and supplementation of charcoal showed reduced (p < 0.05) final live weight, weight gain, feed intake and apparent crude protein digestibility of the birds with increasing inclusion levels of UCRM. Birds fed diets supplemented with charcoal showed higher (p < 0.05) final live weight, weight gain and feed intake than birds fed diets without charcoal. Supplementation of charcoal in diet containing 100 g/kg UCRM resulted in improved (p < 0.05) weight gain when compared with birds fed similar diet but not supplemented with charcoal. Broilers fed diet containing no UCRM but supplemented with charcoal had the highest overall (p < 0.05) final live weight and weight gain, while birds fed diet containing 200 g/kg UCRM supplemented with charcoal recorded the poorest (p < 0.05) final live weight and weight gain. Serum glutamate oxaloacetate transaminase (SGOT) and serum thiocyanate concentration increased (p < 0.05) with increasing dietary inclusion levels of UCRM. Dietary supplementation of charcoal resulted in increased (p < 0.05) concentration of serum glucose and cholesterol and reduced (p < 0.05) SGOT concentration. Birds fed diets containing UCRM had high (p < 0.05) serum thiocyanate concentration irrespective of dietary supplementation or not with 6 g/kg charcoal. In conclusion, supplementation of diet containing up to 100 g/kg UCRM with 6 g/kg charcoal showed improved weight gain without any deleterious effect on serum metabolites.  相似文献   

9.
This experiment was conducted to investigate the effect of star anise essential oil (SAO) supplementation in diets with different energy levels on growth performance, nutrient metabolic efficiency of broilers. One hundred and ninety-two Arbor Acres male broiler chicks at 28 days of age were divided into a 3 × 4 factorial arrangement design with three dietary energy levels (13.41, 12.82, 12.23 MJ/kg) and 4 levels of SAO supplementation (0, 200, 400, and 600 mg/kg of diet). Dietary supplementation with SAO increased (p < .05) apparent metabolic efficiency of CP, EE, GE, and all of the amino acids except Trp. Significant interactions were noted between energy level and SAO administration for metabolic efficiency of CP, all of the amino acids except Cys. Inclusion of SAO enhanced apparent nutrient metabolic efficiency of broilers in a dose-dependent manner, birds supplemented with 400 mg/kg of SAO in high-energy diets appeared to contain highest nutrient metabolic efficiency, moreover, the metabolic efficiency of nutrients in low-energy diets along with 200 or 400 mg/kg of SAO was similar with that in high-energy diets without SAO, which indicated that the SAO might ameliorate the negative effects of reduced dietary metabolic energy on nutrient utilization in broilers.  相似文献   

10.
An experiment using 384 one-day-old male Arbor Acres broilers that were randomly allocated to 4 treatments with 8 replicates in a completely randomized design was conducted to assess the effects of star anise (Illicium verum Hook.f.), essential oil, and leavings on growth performance and antioxidant status of broiler chickens. The treatments were corn-soybean meal based diets supplemented with 5 g/kg star anise, 0.2 g/kg essential oil, and 5 g/kg leavings of the diets for 42 days. All broilers had similar feed conversions over the entire experimental period. However, broilers supplemented with star anise and its essential oil had higher (P < 0.05) ADG and ADFI than those of the control and leavings. Supplementation of star anise and its essential oil increased (P < 0.05) activities of super dismutase, glutathione peroxidase, and catalase but decreased (P < 0.05) content of malondialdehyde in the serum of broilers at 21 d and 42 d of age. And it also increased (P < 0.05) activities of super dismutase and catalase but decreased (P < 0.05) concentrations of malondialdehyde in the liver of broilers at the same periods. Dietary supplementation of star anise and its essential oil improved growth performance and serum and liver antioxidant status. The efficacy is best at 5 g/kg star anise or 0.2 g/kg essential oil in the diet.  相似文献   

11.
A 56-day feeding trial was conducted to investigate the effect of dietary supplementation of dried ginger meal (DGM) on the growth performance, nutrient digestibility, serum parameters, gut morphology, and microflora of growing helmeted guinea fowl (Numidia meleagris). One hundred sixty 28-day-old male keets were assigned to four dietary treatments. There were 40 birds per treatment replicated four times with 10 keets each. The experimental diets consisted of the basal diet (control), ginger-supplemented diets containing 20, 40, and 60 g/kg DGM, respectively. Guinea fowls fed diet supplemented with DGM had higher (P <0.05) final body weight, body weight gain and lower (P <0.05) feed intake. Optimum weight gain was obtained with supplementation level of 36.15-g DGM (R 2?=?0.923). Guinea fowls fed diet supplemented with 40 g/kg DGM recorded the highest (P <0.05) coefficient of total tract apparent digestibility of dry matter, ether extract and longest (P <0.05) duodenal and ileal villus heights. The crypt depth of the duodenum and ileum reduced (P <0.05) with increasing level of dietary supplementation of DGM. Dietary supplementation of DGM resulted in increased (P <0.05) total serum protein, serum albumin and low (P <0.05) serum cholesterol concentration. Ileum content of birds fed diet supplemented with 40 g/kg DGM recorded the highest (P <0.05) lactobacillus count. In conclusion, dietary inclusion of 40-g DGM per kilogram diet is hereby recommended for improved growth, apparent nutrient digestibility, gut morphology, serum chemistry, and stimulation of balanced intestinal microflora in growing guinea fowl.  相似文献   

12.
An experiment was conducted to study the effect of cereal (corn, wheat, barley and sorghum) and supplemental enzyme (a mono-component xylanase) in a 4 × 2 factorial arrangement. A 2-phase feeding program (0 to 21 and 21 to 42 d) was used and 4 iso-caloric, iso-nitrogenous diets were formulated containing corn, wheat, barley, or sorghum as the sole cereal. Diets based on each cereal were fed without or with supplemental xylanase (16,000 BXU/kg) to 8 replicate pens of 10 chicks (5 male : 5 female, Cobb 500) each. Growth performance was recorded at 21 or 42 d posthatch. Excreta was quantitatively collected from 18 to 21 and 38 to 41 d for the measurement of the total tract retention of dry matter (DM), nitrogen (N) and neutral detergent fiber (NDF) and apparent metabolizable energy (AME). Ileal digestible energy (IDE) was measured at the end of the study (42 d posthatch) using titanium dioxide as an indigestible marker. For the overall 42 d period, birds fed barley-based diets had lower feed intake (P < 0.05), lower body weight (P < 0.05) and converted feed into gain less efficiently (P < 0.05) compared with the diets based on corn, wheat or sorghum. Xylanase supplementation improved weight gain in diets based on corn, wheat, and sorghum with the exception of barley-based diets (cereal × xylanase interaction, P < 0.05). Xylanase improved the overall feed conversion ratio (1.885 vs. 1.939; P < 0.05) with the effect being independent of the cereal type. The N retention of barley-based diets was lower (P < 0.05) compared with the other cereals, while xylanase improved N retention (P < 0.05) regardless of the cereal type. NDF digestibility differed (P < 0.05) across cereal (barley > wheat > corn > sorghum) and was improved (P < 0.05) by xylanase supplementation. A significant cereal × xylanase interaction (P < 0.05) was observed for energy measurements, where xylanase improved IDE of the corn-based diet, and AME of corn- and wheat-based diets. Results of the current study demonstrate potential of xylanase in improving nutrient retention and growth performance of broilers fed diets based on variety of cereal grains.  相似文献   

13.
An experiment was conducted to study the effect of different protein meals, with or without enzyme supplementation, on the performance of broilers. A diet based on a combination of protein meals (15% soybean meal, and 5% each of sunflower meal, canola meal, rapeseed meal, and cottonseed meal) was compared with 4 other diets containing 15% soybean meal and 20% of sunflower meal, canola meal, rapeseed meal, or cottonseed meal. Experimental diets were formulated to contain 2,630 kcal of ME/kg and 0.95% digestible lysine, with all other essential amino acids set to meet or exceed the ideal protein ratios. Each diet was fed with or without supplemental exogenous enzyme (Rovabio Excel at 500 g/metric ton of feed) to 6 replicate pens of 50 chicks from 1 to 35 d posthatch as coarse mash. In the cottonseed meal-based diet, supplemental enzyme resulted in high 35-d feed intake and FCR compared with the cottonseed meal-fed groups with no enzyme. There was a significant (P < 0.05) diet × enzyme interaction for 35-d feed intake and FCR. Birds fed the sunflower meal-based diet had significantly (P < 0.05) higher final BW gain and lower FCR as compared with those fed rapeseed meal- or cottonseed meal-based diets, whereas the BW gain of birds fed the rapeseed meal-based diet was significantly (P < 0.05) reduced compared with birds in all other groups. In conclusion, in low-ME broiler diets formulated on a digestible amino acid basis, up to 20% sunflower meal and canola meal can be safely incorporated into the diet. Supplementation of Rovabio failed to exert any positive effect on production parameters when used with diets containing high levels of each of the common protein meals.  相似文献   

14.
A study was carried out to investigate the replacement effect of vitamin E with grape polyphenols (GPP) on antioxidant status, immune response, and organs histopathology in broilers from 1- to 35-d age. One-day-old Hubbard broiler chicks (n = 280) were randomly divided into 28 study units of 10 chicks each. A starter control diet was formulated having 22.5% CP, 3,200 kcal/kg ME, and 100 ppm vitamin E50 [50 IU DL-α-tocopheryl acetate (CON)]. Other dietary treatments were obtained by replacing vitamin E on wt:wt ratio, with 25 [low GPP (LGPP)], 50 [medium GPP (MGPP)], and 75 ppm [high GPP (HGPP)] GPP. Likewise, a control finisher diet (20% CP and 3,200 kcal/kg ME) and LGPP, MGPP, and HGPP diets were formulated having the same proportions of GPP and vitamin E as in the respective starter diets. Each dietary treatment was randomly assigned to 7 replicate pens. As a result of this study, by increasing GPP level in place of vitamin E, total phenolic contents in breast and leg muscles increased linearly (P< 0.05) whereas thiobarbituric acid reactive substances decreased quadratically with MGPP showing the lowest value (P< 0.05). Antibody titers against Newcastle disease virus were higher (P< 0.05) in broilers fed the LGPP and HGPP diets than in those fed the control diet. Antibody titers against infectious bursal disease virus were higher (P< 0.05) in broilers fed the HGPP diet than in all of the remaining dietary treatment groups. Histopathological examination of kidney and liver tissues showed no changes in birds fed LGPP and MGPP diets; however, mild effects were observed in some birds fed HGPP diet. Replacement of vitamin E with GPP resulted in lower cost per kg broiler feed. In conclusion, replacement of 75 ppm vitamin E with GPP improved antioxidant status and immune response of broilers at lower feed cost without any significant effect on histopathology of organs.  相似文献   

15.
The present study was conducted to evaluate the adequacy of applying heat treatment and methionine (Met) supplementation to improve the use of bitter vetch (BV) as a feed ingredient in the growth diet of broilers. A total of 540 Ross-308 chicks were fed various BV-supplemented diets between the ages of 35 and 49 days. The chicks were assigned randomly to one of nine experimental treatments, including raw and cooked bitter vetch seeds at two levels (100 and 200 g/kg) with or without Met (210 mg/kg) supplement and a corn–soybean-based diet as control. Results showed that feeding the 200-g/kg raw BV decreased feed intake by 52% in relation to the control diet (P < 0.05). Cooking the BV did not improve the feed intake. Met supplementation of 100 g/kg raw or cooked BV and 200 g/kg cooked BV resulted to a similar feed intake in the control group. Chicks fed with the 200 g/kg raw BV had an average depressed body weight gain of 90% in comparison to the birds fed with the control diet. The combination of cooking and Met supplementation of this diet resulted to a similar body weight gain to the control diet. Feeding 100 g/kg of raw or cooked BV also reduced (P < 0.05) body weight gain, and Met supplementation of these diets resulted in a body weight gain similar to the control group. Chicks fed with 100 g/kg of raw or cooked BV supplemented with Met or 200 g/kg of cooked BV plus Met has similar feed conversion ratio to the control group. In conclusion, heating BV seeds is not sufficient to overcome the limiting effects of BV seeds on feed intake and weight gain, and that Met supplementation does provide some improvement. The combination of cooking and Met supplementation was more efficient.  相似文献   

16.
This study aimed to determine the effect of different dietary levels of a Chlorella by‐product (CBP) on the growth performance, immune response, intestinal microflora and intestinal mucosal morphology of broilers. In total, 480 one‐day‐old broiler chickens were randomly allotted to four dietary treatments with four replicated pens consisting of 30 chicks. The basal diet was formulated to be adequate in energy and nutrients. Three additional diets were prepared by supplementing 25, 50 or 75 g/kg of CBP to the basal diet. The diets were fed to the broilers ad libitum for 35 days. Result indicated that increasing inclusion level of CBP improved BW gain (linear, p < 0.05). There was no effect of inclusion level of CBP in diets on total cholesterol, triglyceride, aspartate aminotransferase and alanine aminotransferase levels during the 35 days. Plasma IgG, IgM and IgA concentrations increased (linear, p < 0.05) with inclusion level of CBP in diets. Supplementation of CBP in the diets increased (linear, p < 0.05) the concentrations of Lactobacillus in the caecal content and decreased (linear, p < 0.05) the concentrations of Escherichia coli and Salmonella in the caecal content. Villus height increased (linear and quadratic, p < 0.05) with inclusion level of CBP in diets. Crypt depth increased (quadratic, p < 0.05) with inclusion level of CBP, and a decreased villus height: crypt depth ratio (quadratic, p < 0.05) was observed as inclusion level of CBP in diets increased. The results of the current experiment indicate that dietary supplementation of CBP improves growth performance of birds. Dietary CBP has improving Lactobacillus spp. concentrations in the gastrointestinal tract, plasma immunoglobulin concentrations and intestinal mucosal morphology.  相似文献   

17.
This study was designed to evaluate the effects of dietary inclusion of zinc‐methionine (ZnMet) as a replacement for conventional inorganic zinc sources on performance, tissue zinc accumulation and some plasma indices in broiler chicks. A total of 450‐day‐old Ross male broiler chicks were randomly assigned to five pen replicates of nine experimental diets. Dietary treatments consisted of two basal diets supplemented with 40 mg/kg added Zn as feed‐grade Zn sulphate or Zn oxide in which, Zn was replaced with that supplied from ZnMet complex by 25, 50, 75 or 100%. At 42 days of age, three randomly selected birds from each pen were bled to measure plasma metabolites; then, the chicks were slaughtered to evaluate carcass characteristics. Results showed that dietary treatments affected (p < 0.05) feed intake during the starter period, and chicks on Zn oxide diets consumed more feed than sulphate counterparts. Furthermore, dietary substitution of inorganic Zn sources by ZnMet caused improvements (p < 0.01) in body weight gain during all experimental periods. Dietary supplementation of ZnMet improved feed conversion efficiency during 1–21 and 1–42, but not in 21–42 days of age. Complete replacement of inorganic Zn by that supplied from ZnMet caused an increase (p < 0.05) in relative liver weight. Similarly, dietary inclusion of ZnMet increased breast meat and carcass yields and reduced abdominal fat percentage (p < 0.05). Incremental levels of ZnMet increased (p < 0.05) zinc concentrations in liver and thymus, and the highest zinc accumulations were seen in 100% ZnMet‐supplemented birds. Interestingly, introduction of ZnMet into the diets partially in place of inorganic sources resulted in decreases (p < 0.01) in plasma uric acid and triglycerides concentrations. The present findings indicated that dietary ZnMet inclusion in replacement of inorganic sources in addition to improving growth performance, reduced plasma uric acid and triglycerides concentrations, consequently decreased abdominal fat pad and increased carcass meat yield.  相似文献   

18.
Today, several strategies are being used to decrease the serious effects of antibiotics abuse on broilers industry and public health, among which synbiotics are one of the most promising antibiotic alternative. This study was undertaken to assess the effects of synbiotics, which composed of probiotics (Bacillus subtilis) and prebiotics (xylooligosaccharide and mannanoligosaccharide), on growth performance, intestinal morphology, sIgA content and antioxidant parameters of broilers. Four hundred and fifty one‐day‐old commercial Cobb48 broilers were assigned to five treatments consisting of six replicates of 15 birds each pen. Five dietary treatments include basal diets (control), basal diets plus antibiotics (4 mg/kg Xanthomycin), basal diets plus 1 g of probiotics B. subtilis product/kg of diets (4 × 108 cfu/kg), basal diets plus 150 mg/kg xylooligosaccharide (35%) and 1 g/kg mannanoligosaccharide (75%), and basal diets plus synbiotics (1 g of probiotics B. subtilis product/kg of diets (4 × 108 cfu/kg), 150 mg/kg xylooligosaccharide (35%) and 1 g/kg mannanoligosaccharide (75%). The results demonstrated that on 21 and 42 days, dietary supplementation of the synbiotics significantly increased daily weight gain (p < 0.05), feed efficiency (p < 0.05), the villus height and villus:crypt ratio in the duodenum, jejunum and ileum (p < 0.05), as well as intestinal mucosa sIgA content (p < 0.05), serum T‐SOD activity (p < 0.05) and lysozyme content (p < 0.05), comparing with control group. In conclusion, synbiotics (B. subtilis and xylooligosaccharide and mannanoligosaccharide) is one of the safe and ideal dietary supplementations to increase broilers' growth performance by improving small intestinal morphology, sIgA content and antioxidant capabilities.  相似文献   

19.
The objective of this study was to evaluate the effects of inorganic phosphorus source and phytase addition on performance, nutrient digestibility and bone mineralization in broiler chickens. In Exp. 1, 150 two-day old, male broiler chicks were fed a corn-soybean meal basal diet supplemented with phosphorus provided by dicalcium phosphate, tricalcium phosphate or defluorinated rock phosphate. Five cages containing 10 birds were allotted to each of the three treatments. In Exp. 2, 120 three-day old, male broiler chicks were fed the basal diet from Exp. 1 supplemented with 0, 250, 500, or 1,000 FTU phytase per kg of diet. Six cages containing five chicks were allotted to each of the four treatments. In Exp. 1, there was no difference in weight gain, feed intake or feed conversion as a result of feeding the different sources of inorganic phosphorus. The digestibility of phosphorus was significantly lower (P = 0.01) for chicks fed diets supplemented with tricalcium phosphate than for chicks fed the other two diets.  However, despite the lower digestibility, serum phosphorus levels did not differ among the three treatments. For Exp. 2, feed conversion showed a linear improvement (P = 0.03) with increasing levels of phytase inclusion (days 0 to 33).  Phytase supplementation resulted in linear increases in the digestibility of dry matter (P = 0.02), crude protein (P = 0.04) and energy (P < 0.01).  Chicks fed 1,000 FTU/kg phytase had significantly higher bone calcium (P = 0.05) and bone breaking strength (P = 0.04) than chicks fed the basal diet on day 33. In conclusion, the results of the current study indicated that the performance of birds fed diets supplemented with dicalcium phosphate, tricalcium phosphate or defluorinated phosphate was similar and therefore production costs could be lowered by choosing the cheapest inorganic phosphorus source when formulating diets for poultry. When diets were formulated to meet dietary phosphorus requirements, the growth of broilers was not enhanced with phytase supplementation.  However, increases in feed conversion and bone breaking strength and its potential to impact culling and mortality in broiler operations may be sufficient justification for the routine inclusion of phytase in diets fed to broilers.  相似文献   

20.
Zinc (Zn) supplementation source and particle size of feed ingredients are two factors that can affect poultry performance and should be considered for proper feeding of poultry. The objective of the current study was to assess the effects of Zn supplementation source and corn particle size on broiler performance, breast yield, and tibia Zn concentration. Treatments were arranged in a 5 × 2 factorial randomized complete block design with the main effects Zn treatment and corn particle size (550 micron vs. 1,050 micron). Zinc treatments included a basal diet (no added Zn), 80 mg/kg Zn sulfate, and 3 diets with 40 mg/kg Zn sulfate + 40 mg/kg of either Zn-glycine amino acid (AA) chelate (Zn-gly), Zn-AA complex (Zn-AA), or Zn bis(-2-hydroxy-4-methylthio)butanoic acid (Zn-HMTBA). A total of 8 replications per treatment were fed to 23 broilers per pen from d one to 40. A Zn treatment x corn particle size interaction was observed for ending bird weight (EBW; P < 0.05) demonstrating that feeding small particle corn produced larger broilers except when supplemental Zn was not included. Broilers fed small particle corn or diets supplemented with Zn consumed the most feed (P < 0.05); however, FCR was decreased (P < 0.05) by 1.9 points for broilers fed large particle corn diets. Tibia Zn concentration was higher (P < 0.0001) for Zn supplemented diets, but no other treatment effects were observed. In conclusion, Zn supplement source had little effect on broiler performance; however, Zn supplementation per se optimized performance.  相似文献   

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