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1.
A feeding trial was designed to assess the effect of super dosing of phytase in corn–soya‐based diets of broiler chicken. One hundred and sixty‐eight day‐old broilers were selected and randomly allocated to four dietary treatment groups, with 6 replicates having 7 chicks per treatment group. Two‐phased diets were used. The starter and finisher diet was fed from 0 to 3 weeks and 4 to 5 weeks of age respectively. The dietary treatments were consisted of normal phosphorus (NP) group without any phytase enzyme (4.5 g/kg available/non‐phytin phosphorus (P) during starter and 4.0 g/kg during finisher phase), three low‐phosphorus (LP) groups (3.2 g/kg available/non‐phytin P during starter and 2.8 g/kg during finisher phase) supplemented with phytase at 500, 2500, 5000 FTU/kg diet, respectively, to full fill their phosphorus requirements. The results showed that super doses of phytase (at 2500 FTU and 5000 FTU/kg) on low‐phosphorus diet improved feed intake, body weight gain, ileal digestibility (serine, aspartic acid, calcium, phosphorus), blood P levels and bone minerals such as calcium (Ca), P, magnesium (Mg) and zinc (Zn) content. It could be concluded that super doses of phytase in low‐phosphorus diet were beneficial than the normal standard dose (at 500 FTU/kg) of phytase in diet of broiler chicken.  相似文献   

2.
1. The performance of 1680 male broiler chickens was measured from one to 42 d of age. They were given diets with three (125, 165 and 205 mEq/kg) electrolyte balances (sodium + potassium - chloride), two sources of added potassium (carbonate or sulphate) and two anticoccidial agents (90 mg/kg of either monensin or lasalocid). 2. The dietary treatments had no significant effects on the growth performance of broiler chickens in the starter phase. 3. In the finisher phase, the chickens given the diets containing lasalocid utilised food less efficiently that those given the diets containing monensin. 4. There were significant interactions between dietary electrolyte balance and source of added potassium on body weight gains and food:gain ratios in the finisher phase. In diets with an electrolyte balance of 205 mEq/kg, the inclusion of potassium sulphate instead of potassium carbonate increased body weight gains by 3.4% and reduced food:gain ratios by 4.6%. 5. The body weight gains of chickens given the finisher diets containing lasalocid and added potassium carbonate were reduced by 2.6% compared to those of chickens given the diets containing monensin or added potassium sulphate. 6. The litter moisture content was higher in pens with chickens on the diets with an electrolyte balance of 205 mEq/kg than on the diets with either 125 or 165 mEq/kg. Both lasalocid and potassium sulphate tended to increase the litter moisture content. 7. It may be concluded that the inclusion of 90 mg/kg of either monensin or lasalocid in broiler diets does not alter the balance of electrolytes required for optimum growth performance of broiler chickens.  相似文献   

3.
This study was conducted to investigate the effect of spray‐dried porcine plasma (SDPP) in broiler chickens under Salmonella sofia disease challenge. The experiment comprised five starter diets: positive control (no supplement), diet supplemented with in‐feed antibiotics (IFA; salinomycin 0.05% + zinc bacitracin 0.033%) and diets supplemented with SDPP at 10 or 20 g/kg diet. All four of these groups were challenged with S. sofia, while a fifth group was unchallenged and used as the negative control. The experimental diets were fed to 14 days; then, the birds were switched to commercial‐type grower and finisher diets. Oral inoculation of the challenged groups with S. sofia occurred on day 8, 10 and 12. Body weight was significantly higher in the birds fed diets containing IFA and SDPP than in the challenged control group, but it was only significant in starter and grower phases. In general, there was an improvement in the weights of the immune‐related organs, but it was only significant for the weight of the bursa of SDPP‐fed birds at 13 days. At day 13, blood potassium content was lower and the concentrations of IgG and IgM tended to be lower in the birds fed on low‐SDPP starter diets than those of the other groups. There were significant differences in the concentration of lactic acid in the ileum and acetic acid, formic acid, butyric acid and propionic acid in the caeca. Inclusion of SDPP to the starter diets of broiler chicks had positive effects on broiler performance, immunity and gut health during exposure to highly pathogenic conditions.  相似文献   

4.
Two experiments were conducted to determine the efficacy of mannan oligosaccharides (MOS) fed at two levels of Cu on growth and feed efficiency of weanling and growing-finishing pigs, as well as the effect on the immunocompetence of weanling pigs. In Exp. 1, 216 barrows (6 kg of BW and 18 d of age) were penned in groups of six (9 pens/treatment). Dietary treatments were arranged as a 2 x 2 factorial consisting of two levels of Cu (basal level or 175 ppm supplemental Cu) with and without MOS (0.2%). Diets were fed from d 0 to 38 after weaning. Blood samples were obtained to determine lymphocyte proliferation in vitro. From d 0 to 10, ADG, ADFI, and gain:feed (G:F) increased when MOS was added to diets containing the basal level of Cu, but decreased when MOS was added to diets containing 175 ppm supplemental Cu (interaction, P < 0.01, P < 0.10, and P < 0.05, respectively). Pigs fed diets containing 175 ppm Cu from d 10 to 24 and d 24 to 38 had greater (P < 0.05) ADG and ADFI than those fed the basal level of Cu regardless of MOS addition. Pigs fed diets containing MOS from d 24 to 38 had greater ADG (P < 0.05) and G:F (P < 0.10) than those fed diets devoid of MOS. Lymphocyte proliferation was not altered by dietary treatment. In Exp. 2, 144 pigs were divided into six pigs/pen (six pens/treatment). Dietary treatments were fed throughout the starter (20 to 32 kg BW), grower (32 to 68 kg BW), and finisher (68 to 106 kg BW) phases. Diets consisted of two levels of Cu (basal level or basal diet + 175 ppm in starter and grower diets and 125 ppm in finisher diets) with and without MOS (0.2% in starter, 0.1% in grower, and 0.05% in finisher). Pigs fed supplemental Cu had greater (P < 0.05) ADG and G:F during the starter and grower phases compared to pigs fed the basal level of Cu. During the finisher phase, ADG increased when pigs were fed MOS in diets containing the basal level of Cu, but decreased when MOS was added to diets supplemented with 125 ppm Cu (interaction, P < 0.05). Results from this study indicate the response of weanling pigs fed MOS in phase 1 varied with level of dietary Cu. However, in phase 2 and phase 3, diets containing either MOS or 175 ppm Cu resulted in improved performance. Pharmacological Cu addition improved gain and efficiency during the starter and grower phases in growing-finishing pigs, while ADG response to the addition of MOS during the finisher phase seems to be dependent upon the level of Cu supplementation.  相似文献   

5.
Chicks were treated orally on the day of hatch with either fresh or frozen competitive exclusion (CE) cultures (native gut microflora). Chicks were fed either unmedicated feed or one of five commercial broiler starter rations or nine experimental feed mixtures containing varying amounts and combinations of anticoccidial and antimicrobial medicaments. After 2 days, they were challenged with approximately 10(6) colony-forming units of a nalidixic-acid-resistant strain of Salmonella typhimurium. Six days later, chicks were sacrificed and ceca were analyzed for S. typhimurium. Colonization of 2-day-old chicks was prevented or at least greatly reduced in most instances by treatment of chicks with a CE culture, but the efficacy of CE broth cultures stored at -70 C diminished over time. Not all CE cultures tested gave equal protection against Salmonella colonization, and CE cultures were more susceptible to some feed additives than others. Of the commercial or experimental feed tested, only the feed containing the combination of nicarbazin and bacitracin interfered with the protective effect of the CE culture.  相似文献   

6.
In two experiments was investigated whether feeding with an air-dry feed mixed with different amounts of water and/or supplemental ascorbic acid affect performance and carcass compositions of broilers exposed to a high ambient temperature (35 to 37 degrees C for 8 h/d and thermoneutral for 16 h/d). In the first trial, 64 one-week-old male broiler chicks were fed ad libitum in four dietary treatment groups for a 6-week period. Experimental mash diets were prepared by mixing a maize-soybean based standard broiler starter or finisher with tap water in the ratios of 0.0:1.0, 0.5:1.0, 1.0:1.0 and 1.5:1.0 (water:air-dry feed, w/w). More water in the diet increased BWG, DMI, abdominal fat and carcass weight, carcass CP, crude fat, but it deteriorated DM conversion efficiency. In the second experiment, 64 one-week-old male broiler chicks were given air-dry or wet (water:feed, 1.5:1) starter or finisher diets without or with ascorbic acid supplementation (0 and 250 mg/kg air-dry feed, resp.) ad libitum for a 6-week period. Ascorbic acid supplementation increased BWG, carcass weight and carcass CP significantly, while reducing carcass crude fat content. However, feeding broilers with a diet mixed with water in a ratio of 1.5:1.0 increased BWG, DMI, carcass weight and carcass lipid markedly, but deteriorated DM conversion efficiency. There was also a significant interaction between ascorbic acid and wet feeding, whereby ascorbic acid supplementation induced a significant reduction in carcass lipid contents of broilers fed on air-dry diets but not on wet diets. It is concluded that wet feeding, especially an addition of 150% water to produce a porridge like consistency, improved growth performance by increasing fat, ash and protein deposition in the body, while reducing DM conversion efficiency. It is also concluded that under heat stress supplemental ascorbic acid in air-dry diets stimulates broiler performance but not in wet diets.  相似文献   

7.
Waste material from bakeries is an unconventional energy feed source which is available in sufficient quantities for use in small-scale broiler production in South Africa. Small-scale broiler producers do not have access to the computer programs required to balance home-mixed rations. This investigation confirms that the use of dried bakery products (DBP) in a 2-stage, free-choice method can be used to compensate for this lack. A total of 570 day-old male broiler chickens was assigned to 3 feeding treatments: the control group was fed a 2-stage feeding programme using standard commercial starter and grower rations. The 2nd group received a commercial starter ration up to Day 7 and was thereafter given a choice of a commercial starter ration with normal salt content (0.35%) and DBP. The 3rd group was fed a commercial starter ration up to Day 7, then offered a choice of commercial starter ration with a lower salt content (0.1%) and DBP. The low salt alternative was used to test whether the higher salt percentage in DBP influenced the choice of feed by the birds. It was found that the control group consumed significantly more feed (P < 0.05) and was significantly heavier (P < 0.05) than the experimental groups. However, there was no significant difference between the 2 experimental groups, which indicated that salt content did not play a role in the choice of ration. Feed consumption by both experimental groups was about one-third less than the control group, but the profit margin, as calculated using gross margin analysis, was approximately 15 % higher. It was therefore concluded that dried bakery products can be profitably incorporated as an energy feed source, using the free-choice feeding method, in small-scale broiler enterprises.  相似文献   

8.
Dietary manipulation has been seen as one of the practical ways to ameliorate the adverse effects of thermal stress in the hot humid tropical climate. In order to investigate the influence of Curcuma longa (turmeric) rhizome powder on physiological responses and performance under hot humid tropical climate, 240 broiler chicks were randomly assigned to four dietary treatments having four replicates of 15 birds each in a complete randomized design. Broiler birds were fed basal diets and supplemented with 0 (CT), 4 (TG), 8 (FT), and 12 g (SG) of turmeric powder/kg of diet for 8 weeks. Data were collected weekly on feed intake and body weights. Blood samples were collected from eight birds per treatment at week 4 (starter phase) and week 8 (finisher phase) of the experiment for the determination of plasma 3,5,3′-triiodothyronine (T3), superoxide dismutase (SOD), malondialdehyde (MDA). Rectal temperature of the birds was also taken. At 56 days of age, eight birds from each treatment were slaughtered for the determination of relative organ weights. Results showed that the final weights of the birds in FT were significantly higher than those of the birds in TG, SG, and CT. The weight gain of the birds in FT was higher than those of the birds in SG while those of SG were higher than those of TG whose values were higher than that of CT. The feed conversion ratio of the broiler chickens in CT was higher (P?<?0.05) than those of other treatment groups while the birds in FT and SG had similar feed conversion ratios. SOD of birds fed turmeric rhizome powder was higher than the birds in the control group at both starter and finisher phases. Furthermore, MDA of the birds in FT was lower than those of the birds in the other treatment groups at the finisher phase. Plasma T3 was higher in the birds fed turmeric at the finisher phase than chickens in the control group. There was no difference in the rectal temperatures of the birds. To conclude, turmeric rhizome powder improved the physiological response and performance of broiler chicken under hot humid tropical climate in a dose-dependent characteristic and the optimum supplementation rate of 8 g/kg of diet was recorded.  相似文献   

9.
A study was conducted to examine the growth performance and carcass composition of broiler turkeys fed graded levels of roasted soybeans processed by flame roasting. Roasted soybeans were incorporated as a partial replacement of soybean meal in starter (0 or 15% of the diet) and as a partial or complete replacement for soybean meal in grower and finisher diets (0:100, 33.3:66.6, 66.6:33.3, 100:0; roasted full-fat soybeans:soybean meal). At 21 d of age, the birds fed the starter diet with roasted soybeans ate more feed and were heavier than the controls, but feed conversion was similar. Feed consumption and feed conversion were not affected by ratio of roasted soybeans to soybean meal. However, birds fed the diet containing the 66.6:33.3 ratio were heavier than birds fed any other diet. At 84 d of age, carcass CP content of the birds fed roasted soybeans in the starter diet were similar to the control birds, whereas the carcass fat content was lower.  相似文献   

10.
设计３个试验研究了调整营养制度,降低肉仔鸡饲养成本的措施。试验结果表明,让肉仔鸡从３周龄提前到２周龄时由生长前期料换用生长中期料,不影响其３７日龄体重及０～３７日龄的饲料利用。在无严重应激存在的情况下,肉仔鸡上市（４９日龄）前３周内的基础日粮中不补加微量元素和２周内不补加维生素不影响生长和饲料转化率。以上对肉仔鸡生长前、后期营养摄入量的调整均可有效降低饲养成本  相似文献   

11.
The objective of the current study was to evaluate the effect of feeding a thermo-tolerant xylanase in low-energy broiler diets on performance and processing parameters. Evaluation criteria included average broiler BW, FCR, livability, carcass yield, and fat pad yields. The experimental design consisted of 3 nutrient profiles: positive control, negative control 1 (−66 kcal/kg), and negative control 2 (−132 kcal/kg). Two xylanase inclusion programs were included in the negative control 1 and 2 diets; 60 g/t was included in the starter and grower diets with either 60 or 100 g/t in the finisher and withdrawal diets, yielding a total of 7 treatment groups with 8 replicate pens per treatment each containing 42-d-old straight-run chicks per treatment (2,352 total broilers). Broilers were reared in floor pens through 45 d of age. The dietary program consisted of 5 dietary phases: starter (1–15 d), grower 1 (16–23 d), grower 2 (24–31 d), finisher (32–38 d), and withdrawal (39–45 d). Body weights and feed consumption were determined on days of dietary changes, including d 15, 23, 31, 38, and 45. On d 45, 4 male and 4 female broilers per replicate (448 total) were subjected to an 8-h feed withdrawal period and processed to obtain carcass and fat pad weights. Reducing the dietary energy level increased FCR and decreased the fat pad weight of broilers in the negative control 2 treatment compared with the positive control. Inclusion of xylanase during the starter phase increased d 15 BW and reduced FCR. The inclusion of xylanase continued to reduce FCR throughout the trial, as compared with diets without xylanase inclusion. Within this study, we have demonstrated the effectiveness of xylanase inclusion in reduced-energy diets (−66 and −132 kcal/kg) to improve FCR of broilers to that of broilers fed energy-adequate diets.  相似文献   

12.
The aim of this study was to investigate the influence of isoenergetic substitution between the three energy delivering macronutrients in pre‐starter diets on performance and intermediary nutrient metabolism in broiler chickens. From hatch until 5 days of age, 600 chicks, collected during peak of hatch, were fed one of the three experimental pre‐starter diets with isoenergetic (13 MJ metabolisable energy/kg) substitutions between fat (43 vs. 108 g/kg), protein (126 vs. 240 g/kg) and carbohydrates (391 vs. 510 g/kg). After 5 days, commercial grower and finisher diets were provided. Pre‐starter composition influenced body weight until slaughter age, although not statistically verifiable. Broilers fed the low protein (LP) pre‐starter had the lowest body weight in relation to chickens on the low carbohydrate or low fat pre‐starter diet. After hatch, chicks on the LP pre‐starter diet were able to use the residual yolk sac more rapidly to fulfil their protein requirement, which is reflected in small intestine and liver development. Also, plasma metabolite levels were influenced mostly by the LP pre‐starter, indicating that the main focus for the requirements of newly hatched chicks should be on proteins. Furthermore, optimal nutrition during the first day’s post‐hatch should take into account the contribution of the yolk.  相似文献   

13.
This experiment aimed to examine the effect of periodical application of bioactive peptides derived from cottonseed (BPC) in comparison with using sub-therapeutic doses of lincomycin and the excessive inclusion of vitamin E on performance, immunity, total antioxidant capacity of serum and intestinal morphology of broiler chickens. A total of 240 one-d-old male broiler chicks with similar initial weight (Ross strain) were randomly assigned to 6 groups (8 chicks/pen): non-treated group (basal diet), basal diet supplemented with 2 mg/kg lincomycin, basal diet supplemented with 50 IU vitamin E, basal diet supplemented with 6 g BPC/kg in starter period, basal diet supplemented with 6 g BPC/kg in starter and grower periods and basal diet supplemented with 6 g BPC/kg throughout the whole experiment. The highest final body weight was obtained in the group supplemented with BPC in starter and grower periods. In the finisher phase, broilers fed the diet containing BPC in the starter period and in the whole trial had significantly (P < 0.05) better feed conversion ratios (FCR). Jejunal villus height was significantly elevated in broilers supplemented with antibiotic (P < 0.001), furthermore it tended to be greater in broilers fed BPC in the starter period. The jejunal villus height-to-crypt depth ratio was significantly (P < 0.01) higher in broilers fed the diet containing antibiotic in comparison to other groups. Humoral immune response against Newcastle disease vaccine tended to be elevated in broilers fed the diet containing BPC in the whole trial (P > 0.05). Broilers supplemented with BPC in starter and grower, and in the whole trial had significantly (P < 0.05) higher antibody titers against sheep red blood cells (SRBC). The highest total antioxidant capacity was obtained in broilers supplemented with the excessive level of vitamin E, furthermore it tended to improve in broilers fed the diet containing BPC in the whole trial. In summary, the results of the study indicated that addition of BPC in broiler diets in the whole trial could improve FCR, immune responses and total antioxidant activity of serum, and BPC could be used in broiler diets as an alternative to in-feed antibiotics.  相似文献   

14.
Evaluation of transgenic event CBH 351 (StarLink) corn in broiler chicks   总被引：3，自引：0，他引：3  
The influence of transgenic event CBH 351 (StarLink; SL)-derived hybrid corn on the growth performance, health condition and physiological function in broiler chicks, as well as the possible transfer of the cry9C gene and Cry9C protein to blood, liver and muscle were examined in comparison with chicks fed on a diet with non-transgenic corn (SL-F). Bodyweight gain and feed conversion ratio in the chicks fed on a diet with SL were significantly greater than in chicks fed on a diet with SL-F during the starter phase (0–3 weeks of age), but this significant difference disappeared during the finisher phase (4–7 weeks of age). No abnormalities in health condition in either SL or SL-F groups were observed, and livability did not differ significantly between SL and SL-F groups. Moreover, no significant differences in serum biochemical and hematological values, histopathological observation and necropsy findings were observed between SL and SL-F groups at the end of the experiment. The cry9C gene and Cry9C protein were not detected in blood, liver and muscle of chicks at 3, 5 or 7 weeks of age. The results indicate that feeding SL does not influence growth performance, health condition or physiological function in broiler chicks, and the cry9C gene and Cry9C protein are not transferred to the blood, liver and muscles of broilers.  相似文献   

15.
Broiler chicks were fed on a commercial‐type ration containing 20 g oxy‐carotenoids/ton for 5 weeks, half receiving 0.005% roxarsone. All birds were then fed on finisher rations containing a moderate (20 g/ton) to high level (40 g/ton) of oxycarotenoids from food ingredients alone and in combination with 2 and 4 g canthaxanthin/ton for 26 d. The birds given roxarsone in the starter ration also received 0.005% roxarsone in the finisher ration together with the above‐listed oxycarotenoid supplements. Roxarsone was withdrawn from the ration 5 d prior to termination of the study to simulate commercial requirements.

The continuous feeding of 0.005% roxarsone had no effect on weight gain, food conversion or pigmentation as assessed by visual shank scores, using the Roche Yolk Color Fan, and colorimetric assay of total carotenoid concentrations in plasma, toe‐web skin and shank skin. Shank visual scores reflected the increased levels of oxycarotenoids derived from food ingredients alone and the effect of supplemental canthaxanthin. These data show that canthaxanthin is an effective pigmenter adjuvant, when added at 2 to 4 g/ton to rations containing 20 to 40 g of oxy‐carotenoids/ton from food ingredient sources. Concurrent feeding of 0.005% roxarsone, while having no positive effect on pigmentation, had no adverse effect on the pigmenting properties of canthaxanthin.  相似文献   


16.
A total of 252 crossbred pigs were used in two experiments to determine the effect of feeding hydrolyzed feather meal (FM) during the growing-finishing period on animal performance, carcass composition, and pork quality. All pigs were blocked by weight, and dietary treatments were assigned randomly to pens within blocks. In Exp. 1, 24 pens were randomly assigned to one of three dietary treatments: 1) control corn-soybean meal starter, grower, and finisher diets devoid of FM; 2) control diets formulated with 3% FM; and 3) control diets formulated with 6% FM. During the starter phase, there was a quadratic decrease in average daily gain (P < 0.06) and gain:feed (P < 0.01) with increasing FM, and during the grower-II phase, gain:feed increased linearly (P < 0.07) with increasing FM inclusion level. However, dietary FM had no effects (P > 0.10) on performance during the grower-I phase, finisher phase, or in the overall trial. Moreover, carcasses from pigs fed 3% FM had greater (P < 0.05) average backfat depth than carcasses of pigs fed 0 and 6% FM, but FM did not affect (P > 0.10) ham or carcass lean composition. In Exp. 2, 24 pens were randomly allotted to one of four dietary treatments: 1) positive control corn-soybean meal-based starter, grower, and finisher diets; 2) negative control corn-soybean meal- and wheat middlings-based starter, grower, and finisher diets; 3) negative control diets formulated with 3% FM; and 4) negative control diets formulated with 6% FM. Dietary FM had no effect (P > 0.10) on average daily gain, average daily feed intake, or gain:feed during any phase of the experiment. Ham weight decreased linearly (P < 0.04), whereas ham lean weight increased linearly (P < 0.09), with increasing levels of FM in the diet. Pork from pigs fed 3% FM tended (quadratic effect, P < 0.10) to receive higher Japanese color scores than pork from pigs fed either negative control or 6% FM diets. Moreover, pork color became lighter (P c 0.08), less red (P < 0.001), and less yellow (P < 0.003) as FM level was increased in swine diets. Results from these two experiments indicate that as much as 6% FM can be incorporated into isolysinic diets of growing-finishing pigs without adversely impacting animal performance, carcass composition, or pork quality.  相似文献   

17.
本研究通过四次共620头猪的饲养试验,一次消化试验和144头猪的屠宰测定,就蛋白质营养水平问题,对杜湖猪<杜洛克×湖北白猪杂交一代>肥育性状和胴体性状的影响进行了研究。试验在等能量水平下,CP以2％的梯度、育肥前期由10.5％递增至18.7％,育肥后期由10.5％递增至16.8％。结果表明,饲养杜湖猪适宜蛋白质水平为:前期CP14.5％(含赖氨酸0.7％),能蛋比26.7:1;后期CPl2.5％(含赖氨酸0.54％),能蛋比32:1。  相似文献   

18.
Sixteen groups, each of about 30 male or female Ross 1 chicks, were given pelleted diets containing 0, 5, 10 or 20% yeast in place of herring meal. The diets were given from 1 d of age for 4 weeks; from 4 to 8 weeks the birds were given a common broiler finisher diet. Replacing up to 10% herring meal by yeast did not significantly affect live‐weight at 4 weeks of age but food conversion efficiency was poorer with the diet containing 10% yeast. Birds given the diet containing 5% yeast to 4 weeks of age were significantly heavier at 8 weeks. The diet with 20% yeast significantly depressed growth at 4 and 8 weeks of age.

The use of yeast in broiler finisher diets was investigated in a second experiment. Birds similar to those used in the first experiment were given diets containing yeast at levels of 0, 5, 10 or 20% from 4 to 8 weeks of age. Live‐weight at 8 weeks was not significantly affected by level of yeast in the diet; food conversion efficiency was significantly better with the 20% yeast diet. Blood plasma uric acid levels were not affected by the level of yeast in the diet.  相似文献   


19.
In a completely randomized block design with 96 Cobb-500 broilers, a study was conducted to evaluate the potential of dietary inclusion of sprouted then roasted guar bean in broiler diets. The 96 male day-old broiler chicks, blocked by pen into equal weight groups of six chicks replicated four times per treatment, were randomly allocated to treatment diets containing graded levels of sprouted then roasted guar bean meal (GBM) at 0, 50, 100 and 150 g kg?1 inclusion level. The guar bean was sprouted and roasted to reduce guar gum effect. Total feed intake decreased significantly as the guar bean meal content increased in the starter phase (P < 0.05), but no significant differences in intake of the finisher phase (P > 0.05) were observed. Diets containing 0 and 50 g kg?1 GBM recorded significantly higher total feed intake compared to the diet containing 150 g kg?1 GBM. Although average weight gain was not significantly different in birds fed 0 and 50 g kg?1 GBM diets, it was significantly higher than in birds fed on 100 and 150 g kg?1 GBM diets. Feed conversion ratio was not significantly different among treatment groups (P > 0.05) but showed a general decreasing trend with increasing guar bean meal inclusion level, the effect being more pronounced during the starter phase. In conclusion, the optimum inclusion level of sprouted then roasted guar bean meal in broiler diets is 50 g kg?1.  相似文献   

20.
This study was conducted to compare the effects of exchanged diets with identical energy level on characteristics of slow‐growing (WENs Yellow‐Feathered Chicken, WYFC) and fast‐growing (White Recessive Rock Chicken, WRRC) female chickens. A total of 1450 WYFC and 1150 WRRC 1‐day‐old female hatchlings were used. A high‐nutrient‐density (HND) diet and a low‐nutrient‐density (LND) diet were formulated for three phases. A completely randomized experimental design with a 2 × 2 factorial arrangement (diet and breed), each with five replicates of 145 and 115 birds, was applied. The results showed that WRRC had a higher body weight (BW), average daily feed intake and average daily gain than WYFC throughout the experiment (p < 0.05). WYFC that were provided with HND groups had a higher BW only in the starter and grower phases, whereas WRRC had a higher BW in the HND group than in LND groups throughout the experiment. The feed:gain ratio and protein efficiency ratio (PER) were better for WRRC in the starter and grower phases; however, these ratios were better for WYFC in the finisher period. The LND groups had a higher PER throughout the experiment for both breeds (p < 0.05). The breast and leg muscle weights were higher for WRRC compared with WYFC during the grower and finisher phases (p < 0.05). WRRC had a lower liver index but higher serum UA and alkaline phosphatase (ALP) concentrations than WYFC (p < 0.05). No diet effect was observed on organ indices, muscle yields or blood responses. The gene expressions of Rheb, TOR, S6K1 and 4E‐BP1 in gastrocnemius muscle were the highest in the WYFC‐LND groups at 63 and 105 days (p < 0.05). These findings suggested that different genotypes respond differently to changes in dietary nutrient density and that lower‐nutrient‐density diets are optimal for the long‐term housing of broiler chickens.  相似文献   

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