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1.
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   

2.
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   

3.
In vivo and in vitro 3 x 2 factorial experiments were conducted concurrently to evaluate the incorporation of 0, 15, or 30% sugar beet pulp (SBP) as an energy source in diets fed to growing Holstein steers with either soybean meal (SBM) or alcohol-treated, defatted soybean flakes (ATSBF) as primary supplemental protein sources. Three groups of 42 Holstein steers each were fed six different diets from 54 kg initial BW to 320 kg in three experimental periods. There were no overall SBP level x protein source interactions (P greater than .05). Beet pulp level tended to decrease ADG (linear, P = .05) and increase feed/gain (linear, P less than .05) and DMI (quadratic, P less than .05). Each grower diet was used in a substrate for ruminal microbial metabolism in six dual-flow, continuous-culture fermenters. Organic matter and carbohydrate digestion were similar (P greater than .05) among diets. Increasing dietary levels of SBP caused a concomitant increase (P less than .05) in acetate and decrease (P less than .05) in butyrate and isobutyrate concentrations. Beet pulp level x protein source interactions (P less than .05) were observed for CP degradation, ammonia and nonammonia N, and dietary N flow. Crude protein degradation was higher (P less than .05) for the 0% SBP with SBM diet (81.3%) than for the 30% SBP with ATSBF diet (64.4%). Efficiency of bacterial synthesis was similar (P greater than .05) among diets. Results indicated that SBP is an effective dietary energy source for high-energy grower diets at 15 or 30% of the DM but may cause a decrease in some performance traits. There were no nutritional benefits of using ATSBF vs SBM as the supplemental N source.  相似文献   

4.
Two experiments were completed to compare the supplemental effects of yeast Saccharomyces cerevisiae and sub-therapeutic antibiotics in high-fibre and low-protein diets for broiler chicks. In experiment 1, yeast was added at 1.5, 3.0 and 6.0 g kg-1 while penicillin, tylosin or neoterramycin were added at 150 mg kg-1 into different batches of a high-fibre diet containing 250 g kg-1 palm kernel meal. Saccharomyces cerevisiae and antibiotics increased BW, BWG, FCR, feed intake, carcass and breast weights above the control. Small intestine weight was reduced by antibiotics, while yeast caused a lower deposition of abdominal fat. Liver weights of different treated broilers were similar. The performance indices were superior on penicillin and 3.0 g kg-1 yeast compared to other supplements evaluated. In the second experiment, 1.5 and 3.0 g kg-1 of yeast, and 0.75 mg kg-1 of procaine penicillin, zinc bacitracin and tylosin were separately added to a 180 g kg-1 crude protein diet. Performance of the chicks with additives was compared with unsupplemented negative and positive controls containing 180 and 210 g kg-1 crude protein respectively. Broilers fed with supplements had superior BW, BWG, FCR and feed intake compared to the negative control, but carcass data were similar. Dietary penicillin increased BW, BWG, feed intake more than other supplements, but yeast stimulated higher FCR. Data from both studies indicated that Saccharomyces cerevisiae comparatively increased growth and carcass weight and reduce abdominal fat, therefore, it can serve as a natural substitute for antibiotics in broiler diet.  相似文献   

5.
The objective of this study was to investigate the effect of dietary citric acid (CA) on the performance and mineral metabolism of broiler chicks. A total of 1720 Ross PM3 broiler chicks (days old) were randomly assigned to four groups (430 in each) and reared for a period of 35 days. The diets of groups 1, 2, 3 and 4 were supplemented with 0%, 0.25%, 0.75% or 1.25% CA by weight respectively. Feed and faeces samples were collected weekly and analysed for acid insoluble ash, calcium (Ca), phosphorus (P) and magnesium (Mg). The pH was measured in feed and faeces. At the age of 28 days, 10 birds from each group were slaughtered; tibiae were collected from each bird for the determination of bone mineral density, total ash, Ca, P, Mg and bone‐breaking strength, and blood was collected for the measurement of osteocalcin, serum CrossLaps®, Ca, P, Mg and 1,25(OH)2Vit‐D in serum. After finishing the trial on day 37, all chicks were slaughtered by using the approved procedure. Birds that were fed CA diets were heavier (average body weights of 2030, 2079 and 2086 g in the 0.25%, 0.75% and 1.25% CA groups, respectively, relative to the control birds (1986 g). Feed conversion efficiency (weight gain in g per kg of feed intake) was also higher in birds of the CA‐fed groups (582, 595 and 587 g/kg feed intake for 0.25%, 0.75% and 1.25% CA respectively), relative to the control birds (565 g/kg feed intake). The digestibility of Ca, P and Mg increased in the CA‐fed groups, especially for the diets supplemented with 0.25% and 0.75% CA. Support for finding was also indicated in the results of the analysis of the tibia. At slaughter, the birds had higher carcass weights and higher graded carcasses in the groups that were fed the CA diets. The estimated profit margin was highest for birds fed the diet containing 0.25% CA. Birds of the 0.75% CA group were found to have the second highest estimated profit margin. Addition of CA up to a level of 1.25% of the diet increased performance, feed conversion efficiency, carcass weight and carcass quality, but only in numerical terms. The addition of CA up to 0.75% significantly increased the digestibility of macro minerals, bone ash content, bone mineral density and bone strength of the broiler chicks. It may, therefore, be concluded that the addition of 0.75% CA in a standard diet is suitable for growth, carcass traits, macromineral digestibility and bone mineral density of broiler chicks.  相似文献   

6.
The effect of ractopamine, a beta-adrenergic agonist, on growth, nutrient utilization, and carcass composition was studied in pigs fed either 18% CP, 12% CP, or 18% CP restricted (RES = 67% of ad libitum) diets. The 18 and 12% CP diets provided 3.52 and 3.68 Mcal of DE/kg, respectively. All pigs were fed a low-protein (12% CP) diet during pretreatment growth from 15 to 60 kg. Ractopamine at 20 or 30 ppm (30 ppm for RES pigs) in the diet was fed from 60 kg live BW until slaughter at 105 kg (9 pigs/treatment). No ractopamine treatment effect (P greater than .05) was observed for either daily gain or gain/feed, although gain/feed was improved by 8% in both of the ad libitum groups. Ractopamine treatment resulted (P less than .01) in an overall reduction of carcass lipid by 8%, an increase of carcass protein by 5%, and a 21% improvement in the efficiency of protein utilization; the greatest changes occurred in the pigs fed the 12% CP diet (-17%, +11%, and +32%, respectively). The ad libitum daily feed intake was 15% less for pigs fed the 12% CP diet than for those fed the 18% CP diet (P less than .01), and there was a 10% reduction in intake of both diets with the addition of ractopamine (P less than .05). Both carcass lipid and protein deposition seemed to be closely related to energy intake (P less than .01).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

7.
Fifty-eight Holstein and 58 crossbred beef steers were individually fed one of four isonitrogenous diets to evaluate the effects of forage source (corn silage and alfalfa haylage) and protein source (soybean meal and fish meal) on feedlot performance. Phase 1 diets (up to 354 kg of BW) were 40% forage and 60% concentrates and were fed for 70 to 136 d (depending on diet and breed group). Phase 2 diets (354 kg of BW until slaughter) were 20% forage and 80% concentrates and were fed for 127 to 150 d (depending on diet and breed group). Slaughter end points were .6 cm of 12th rib fat for Holsteins and 1.0 cm of rib fat for crossbreds using real-time ultrasonic estimates. The steers were fed for a maximum of 330 d each year. Forage source was a significant component of variation for most growth, efficiency, and carcass traits. Holstein and crossbred steers fed alfalfa haylage had significantly lower average daily gain, feed efficiency, dressing percentage, and empty body fat and required more days on feed to reach slaughter end points, but had higher total feed energy intake available for production. Steers fed corn silage diets had significantly greater energetic efficiency (P less than .05) than those fed alfalfa haylage, due to increased use of ME to produce fat in the carcass. Protein type did not influence gain, feed or energetic efficiency, energy intake, or most carcass traits. A significant protein system x forage source interaction among the four diets was detected for crossbred steers fed corn silage and fish meal, for which there was significantly greater feed conversion with lower energy intake above maintenance, possibly due to better fiber digestion and(or) amino acid flow to the lower tract. Alfalfa haylage plus soybean meal diets decreased (P less than .05) the percentage of Holsteins grading USDA Choice or higher. These results indicate that corn silage, because of greater energy concentration, was a more desirable forage in feedlot diets composed of less than or equal to 40% forage and that protein type (soybean meal and fish meal) in growing diets is not an important factor in feedlot performance or carcass traits of Holstein or crossbred steers that are fed these diets.  相似文献   

8.
The effects of dietary amino acid (AA) density and AME on the growth and meat yield of summer-reared Cobb × Cobb 700 (CCB-700) broilers were evaluated. In addition, the responses of CCB-700 and Cobb × Cobb 500 (CCB-500) broilers to dietary AME levels (with low AA) were compared. All chicks were fed through a starter, grower, finisher, and withdrawal phase program. Grow-out performance, carcass traits, meat yield, and feed cost efficiency were evaluated using 2 separate 2-way ANOVA based on 2 separate 2 × 2 factorial arrangements of treatments. Each group includes 14 replicate pens with 14 chicks/replicate. Mortality was not affected by treatment; however, as compared with birds fed other diets, feeding CCB-700 broilers a low-AME and high-AA density diet decreased feed intake and BW on d 35, 42, and 54, and decreased carcass, breast, wing, front half, and back half weights on d 55. The CCB-500 broilers consumed more feed and gained more weight as compared with CCB-700 broilers at 14, 28, and 35 d of age. However, at 55 d of age, breast weight and wing yield were observed to be higher in the CCB-700 than in the CCB-500 broilers. However, the back half (drumstick and thigh) weights were lower in the CCB-700 than in the CCB-500 broilers. In conclusion, without affecting feed costs, broiler performance and carcass yield were affected by diet in both strains. More specifically, a higher AME diet and lower AA density increased the yield of all cut-up parts, except for legs, in summer-reared CCB-700 chicks.  相似文献   

9.
A study was conducted to invesstigate the housefly maggot meal (HMM) as an alternative protein source to replace the soybean meal in broiler chick's diet. A total of 720 1-day-old male broiler chicks were divided into three groups and fed diets formulated with HMM to replace soybean meal at the rate of 0%, 4% and 8%. The study lasted for 42 days in two phases. Results showed that HMM addition did not markedly affect body weight, average daily body weight gain and average daily feed intake of the broiler chicks. Feed conversion ratio increased linearly (1–21 days) in starter or quadratically (22–42 days) in the grower phase. HMM non-significantly increased the feed intake and body weight during the grower phase. Slight changes were observed for decrease of blood biochemical indices in the platelets (day 21), and alkaline phosphatase and lysozyme (day 42), and increase for red blood cells, packed cell volume, total protein and uric acid on day 42; however, the fluctuations were within the physiological range. Non-significant effects were observed for carcass composition and meat quality, except that HMM numerically reduced the shear force of breast muscle (linear, p = .058). These results are the strong evidence that HMM can be used as an alternative protein source at 8% in broiler chick's diet without any adverse effect on chick's performance.  相似文献   

10.
A 42-d broiler pen trial was conducted to evaluate the effects of dietary mannan oligosaccharide (MOS) from either of 2 commercial products, Bio-Mos (Alltech Inc., Nicholasville, KY) or SAF-Mannan (S. I. LeSaffre, Cedex, France) each at 2 levels of inclusion on live performance. The MOS, derived from the outer portion of yeast cell walls, is reported to have several beneficial modes of action including 1) pathogen adsorption (agglutination); 2) improved intestinal integrity (e.g., villi height); and 3) immune modulation. Diets were fed in 3 phases, and treatments included a control, 2 Bio-Mos treatments (1.0 kg/ton in starter and 0 or 0.5 kg/ton in grower and finisher feeds), and 2 SAF-Mannan treatments (0.5 kg/ton in starter and 0 or 0.5 kg/ton in grower and finisher feeds), according to the manufacturers’ recommendations. Birds fed Bio-Mos at 1.0/0.5/0.5 (starter/grower/finisher) kg/ton diets had significantly greater BW at 42 d than birds fed control or SAF-Mannan-supplemented diets, whereas results for the Bio-Mos 1.0/0/0 kg/ton diets were intermediate. Supplementation of diets with Bio-Mos at 1.0/0.5/0.5 kg/ton may improve broiler BW at market ages compared with the unsupplemented diets. Feed consumption was lower from 0 to 21 d in the SAF-Mannan treatments compared with other treatments. No significant differences were found for feed conversion or mortality for any of the treatments. Overall, Bio-Mos had a greater effect on bird BW compared with the other variables measured.  相似文献   

11.
We investigated the effects of wood kraft pulp (KP) feeding on feed digestibility and rumen fermentation of Japanese Black (JB) steer in the middle fattening stage. The feeding experiment was carried out a replicated 3 × 3 Latin square design using six JB steers (16.2 ± 0.8 months of age). Steers were fed rice straw and three concentrated feeds: commercial formula feed (control), formula feed containing 7.5% KP on a dry matter (DM) basis (7.5% KP), and formula feed containing 15% KP on a DM basis (15% KP). Feed digestibility and rumen fermentation parameters were recorded for 3 days during the measurement period, after an adaptation phase of 11 days. There was no significant difference in DM intake per day among diets. A slightly higher digestibility of neutral detergent fiber was observed in steers fed 15% KP, compared with those fed other diets (P = 0.059). The butyric acid ratio in rumen fluid was higher in steers fed KP diets than in steers fed control (P = 0.083). The average ruminal pH was unaffected by KP diets. This study suggests that replacing 15% of concentrated feed with KP has little effect on feed digestibility and rumen fermentation in JB fattening steer.  相似文献   

12.
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   

13.
Four trials were conducted to determine the effects of adding various levels and types of fat to dry-rolled corn (DRC) finishing diets containing 0 or 7.5% forage. In Trial 1, 88 yearling steers (mean BW = 352 +/- 38 kg) and 176 heifers (mean BW 316 +/- 15 kg) were blocked by sex and weight into four replications. Treatments were 0, 2, 4, or 6% (DM basis) bleachable fancy tallow (BT) fed with 0 or 7.5% (DM basis) forage. Addition of BT to the 7.5% forage diet had no effect on ADG or gain/feed (G/F). However, adding BT to the all-concentrate diet decreased ADG (linear, P < .01) and G/F (linear, P = .08). In Trial 2, 184 yearling steers (mean BW = 347 +/- 21 kg) and 144 heifers (mean BW 322 +/- 8 kg) were blocked by sex and weight into six replications. Fat treatments were 0% fat, 4% BT, or 4% animal-vegetable oil blend (A-V); each fat treatment was fed with 0 or 7.5% forage. Across forage levels, the addition of fat increased (P < .01) ADG and G/F for cattle fed DRC. In Trial 3, 18 crossbred wether lambs (mean BW = 44.4 +/- 2.5 kg) were fed DRC and 7.5% forage and allotted randomly to the same fat treatments fed in Trial 2. Apparent total tract fat digestibility increased (P < .01) with the addition of BT or A-V. In Trial 4, 40 crossbred wethers (mean BW = 25 +/- 4.1 kg) and 16 ewes (mean BW = 23 +/- 2.7 kg) were individually fed 7.5% forage diets containing 0, 1, 2, or 4% BT. Addition of BT increased (linear, P = .10) G/F. In summary, fat addition to DRC finishing diets fed to yearling cattle did not consistently affect gain/feed, feed intake, and ADG.  相似文献   

14.
Four experiments were conducted with a total of 2288 pekin ducks. Day-old ducklings were group-penned on straw bedding and were fed complete, pelleted diets ad libitum for up to 49 days depending on experiment. In each experiment, starter diets (until day 21) and grower diets (from day 22) were used adequate in ME content and nutrient content. The sum of wheat, rye, and triticale amounted to at least 57% (starter diet) and 63% (grower diet), respectively. The inclusion level of wheat, rye, and triticale was different between experiments, with a maximum rye inclusion of 45%. Five different enzyme preparations all having, 1,4-beta-xylanase as the main activity were considered in this study with either one (2 preparations) or three (3 preparations) levels of supplementation. The effect of enzyme supplementation on ileal digesta viscosity was studied at the end of two experiments comprising 4 enzyme preparations. A significant reduction in digesta viscosity was determined for all preparations. The viscosity of digesta was higher in birds that were fed 45% rye in their diet as compared to those fed a diet based on triticale and wheat, even with enzyme supplementation. Differences in digesta viscosity were not reflected in growth or feed conversion data. In one experiment, the body weight of ducks on day 21 was significantly improved by enzyme supplementation. This effect disappeared with progress in experiment. In another experiment, feed intake was significantly improved with enzyme supplementation. Apart from this, no statistically significant improvement in performance could be detected. On overall average, the final BW of ducks fed an enzyme was (as compared to the unsupplemented control = 100), 100, and the feed conversion ratio was 101. There is no indication from the growth and feed conversion data that an enzyme effect becomes more pronounced with increasing inclusion rate of soluble NSP by rye. It is concluded that supplementary xylanases are efficient in reducing digesta viscosity in ducks fed diets with high inclusion of wheat, rye and triticale. No consistent effect of enzyme supplementation, however, can be expected on growth and feed conversion.  相似文献   

15.
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   

16.
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   

17.
Four experiments were conducted to investigate the effects of distillers dried grains with solubles (DDGS) and dietary S on feed preference and performance of pigs. In a 10-d feed preference experiment (Exp. 1), 48 barrows (20.1 ± 2.2 kg of BW) were randomly allotted to 3 treatment groups, with 8 replicate pens per treatment and 2 pigs per pen. A control diet based on corn and soybean meal, a DDGS diet containing 20% DDGS, and a DDGS-sulfur (DDGS-S) diet were prepared. The DDGS-S diet was similar to the DDGS diet with the exception that 0.74% CaSO(4) was added to the diet. Two diets were provided in separate feeders in each pen: 1) the control diet and the DDGS diet, 2) the control diet and the DDGS-S diet, or 3) the DDGS diet and the DDGS-S diet. Preference for the DDGS diet and the DDGS-S diet vs. the control diet was 35.2 and 32.6%, respectively (P < 0.05), but there was no difference between the DDGS diet and the DDGS-S diet. In Exp. 2, a total of 90 barrows (10.3 ± 1.4 kg of BW) were allotted to 3 treatments, with 10 replicate pens and 3 pigs per pen, and were fed the diets used in Exp. 1 for 28 d, but only 1 diet was provided per pen. Pigs fed the control diet gained more BW (497 vs. 423 and 416 g/d; P < 0.05) and had greater G:F (0.540 vs. 0.471 and 0.455; P < 0.05) than pigs fed the DDGS or the DDGS-S diet, but no differences between the DDGS and the DDGS-S diets were observed. In a 10-d feed preference experiment (Exp. 3), 30 barrows (49.6 ± 2.3 kg of BW) were allotted to 3 treatment groups, with 10 replicates per group. The experimental procedures were the same as in Exp. 1, except that 30% DDGS was included in the DDGS and DDGS-S diets and 1.10% CaSO(4) was added to the DDGS-S diet. Feed preference for the DDGS and the DDGS-S diets, compared with the control diet, was 29.8 and 32.9%, respectively (P < 0.01), but there was no difference between the DDGS and the DDGS-S diets. In Exp. 4, a total of 120 barrows (34.2 ± 2.3 kg of BW) were fed grower diets for 42 d and finisher diets for 42 d. Diets were formulated as in Exp. 3. Pigs on the control diets gained more BW (1,021 vs. 912 and 907 g/d; P < 0.05) and had greater G:F (0.335 vs. 0.316 and 0.307; P < 0.05) than pigs fed the DDGS or DDGS-S diet, respectively, but no differences between pigs fed the DDGS and the DDGS-S diets were observed. In conclusion, dietary S concentration does not negatively affect feed preference, feed intake, or growth performance of weanling or growing-finishing pigs fed diets based on corn, soybean meal, and DDGS.  相似文献   

18.
本试验旨在研究在低粗蛋白质(CP)饲粮中添加甘氨酸(Gly)对肉仔鸡生长性能、胴体组成和血液生化指标的影响。选用180只1日龄健康爱拔益加(AA)肉仔鸡(公雏),随机分为3组,每组6个重复,每个重复10只。3组分别为:正对照(PC)组,前期和后期饲粮CP水平分别为22.0%和20.0%;负对照组,前期和后期饲粮CP水平分别为18.0%和15.5%;Gly组,在负对照组基础上添加Gly,使饲粮Gly和丝氨酸水平为2.32%。试验期42 d,分为前期(1~21 d)和后期(22~42 d)2个阶段。结果表明:1)饲粮CP水平降低4.0~4.5个百分点,试验1~21 d的料重比(F/G)显著升高(P0.05),22~42 d的平均日增重(ADG)显著降低(P0.05);添加Gly后,1~21 d F/G显著降低(P0.05),22~42 d ADG显著升高(P0.05),达到了与PC组相似的生长性能。2)CP水平降低,肉仔鸡42日龄胸肌率降低了9.5%(P0.05)、腹脂率提高了60.3%(P0.05);添加Gly后,胸肌率提高了17.6%(P0.05),腹脂率降低了34.6%(P0.05),获得了与PC组相似的胴体组成。CP水平降低、添加Gly均未显著影响屠宰率、全净膛率和腿肌率(P0.05)。3)各组间血液生化指标均无显著差异(P0.05)。可见,低CP饲粮中添加Gly可以改善生长性能和胴体组成,结果提示了Gly在肉仔鸡低CP饲粮中的可应用性。  相似文献   

19.
Two experiments were conducted to determine the effects of feeding reduced-CP, AA-supplemented diets at two ambient temperatures (Exp. 1) or three levels of dietary NE (Exp. 2) on pig performance and carcass composition. In Exp. 1, 240 mixed-sex pigs were used to test whether projected differences in heat increment associated with diet composition affect pig performance. There were 10 replications of each treatment with four pigs per pen. For the 28-d trial, average initial and final BW were 28.7 kg and 47.5 kg, respectively. Pigs were maintained in a thermoneutral (23 degrees C) or heat-stressed (33 degrees C) environment and fed a 16% CP diet, a 12% CP diet, or a 12% CP diet supplemented with crystalline Lys, Trp, and Thr (on an as-fed basis). Pigs gained at similar rates when fed the 16% CP diet or the 12% CP diet supplemented with Lys, Trp, and Thr (P > 0.10). Pigs fed the 12% CP, AA-supplemented diet had a gain:feed similar to pigs fed the 16% CP diet when housed in the 23 degrees C environment but had a lower gain:feed in the 33 degrees C environment (diet x temperature, P < 0.01). In Exp. 2, 702 gilts were allotted to six treatments with nine replicates per treatment. Average initial and final BW were 25.3 and 109.7 kg, respectively. Gilts were fed two levels of CP (high CP with minimal crystalline AA supplementation or low CP with supplementation of Lys, Trp, Thr, and Met) and three levels of NE (high, medium, or low) in a 2 x 3 factorial arrangement. A four-phase feeding program was used, with diets containing apparent digestible Lys levels of 0.96, 0.75, 0.60, and 0.48% switched at a pig BW of 41.0, 58.8, and 82.3 kg, respectively. Pigs fed the low-CP, AA-supplemented diets had rates of growth and feed intake similar to pigs fed the high-CP diets. Dietary NE interacted with CP level for gain:feed (P < 0.06). A decrease in dietary NE from the highest NE level decreased gain:feed in pigs fed the high-CP diet; however, gain:feed declined in pigs fed the low-CP, AA-supplemented diet only when dietary NE was decreased to the lowest level. There was a slight reduction in longissimus area in pigs fed the low-CP diets (P < 0.08), but other estimates of carcass muscle did not differ (P > 0.10). These data suggest that pigs fed low-CP, AA-supplemented diets have performance and carcass characteristics similar to pigs fed higher levels of CP and that alterations in dietary NE do not have a discernible effect on pig performance or carcass composition.  相似文献   

20.
An experiment was conducted to evaluate the effect of substituting different levels of hazelnut kernel oil meal (HKM) for soybean meal (SBM) in diets for broiler. A total of 450 one-day-old female Ross 308 broiler chicks were allocated randomly to three treatment groups of 150 birds each in a randomized design. Each treatment group consisted of five replicates each of 30 chicks. All diets (in mash form) were formulated to meet nutrient concentrations recommended for broilers. The experiment lasted for six weeks. In the experiment, an SBM control (SBM) diet was compared to two HKM diets, replacing 50 (50HKM) and 100% (HKM) of SBM protein, respectively. Body weight gain, feed intake and feed conversion ratio of broilers were adversely affected ( P  < 0.05) by the HKM diets at 42 days of age. Broilers fed 50HKM and HKM had growth performances similar ( P  > 0.05). The carcass yield and abdominal fat pads of birds fed diets with SBM were higher ( P  < 0.05) than those of chicks fed the 50HKM and HKM diets. The edible inner organ weight of chicks fed diets with HKM was the heaviest ( P  < 0.05). It is concluded that SBM cannot be replaced even up to 50% with HKM in commercial broiler diet.  相似文献   

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