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Energy values of canola meal, cottonseed meal, bakery meal, and peanut flour meal for broiler chickens determined using the regression method
Energy values of canola meal, cottonseed meal, bakery meal, and peanut flour meal for broiler chickens determined using the regression method F. Zhang and O. Adeola1 Department of Animal Sciences, Purdue University, West Lafayette, IN 47907
Key words: bakery meal, canola meal, cottonseed meal, metabolizable energy, peanut flour meal 2016 Poultry Science 0:1–8 http://dx.doi.org/10.3382/ps/pew239
INTRODUCTION
ucts and different processing procedures, there is a lot of variability in nutrients and energy contents (Slominski et al., 2004). Peanut flour meal (PFM) is also a good source of plant protein and contains high concentrations of energy, but there is limited data on energy value for broiler chickens. Due to the recent challenges in the poultry industry of feed costs and the potential benefits of using alternative ingredients in broiler chicken diets, more data on the ileal digestible energy (IDE), metabolizable energy (ME) and nitrogen-corrected metabolizable energy (MEn ) are needed to optimize diet formulation. Therefore, the objective of the current study was to determine the IDE, ME, and MEn of CM, CSM, BM, and PFM for broiler chickens using the regression method.
Canola meal (CM) and cottonseed meal (CSM) are the byproducts of the process used to extract oil from canola or cotton seeds, which contain 38 or 41% crude protein (CP), respectively, and considerable amount of energy (NRC, 1994). Those two ingredients are increasingly used in non-ruminant animals diets as proteinsource substitutes for soybean meal (SBM), but are still restricted to partial replacement of SBM because of deficiencies in some essential amino acids (AA), high concentrations of anti-nutrients such as glucosinolates and gossypol, as well as the low available energy content (Heywang and Kemmerer, 1966; Bell, 1993). Bakery meal (BM) is a combination byproduct derived from the baking and cereal industries, such as wheat products, pasta, potato chip waste, cakes, and breakfast cereals (Almeida et al., 2011). The BM is high in fat and carbohydrates, which make it an important energy feedstuff that can be used to partially replace corn in poultry diets. However, due to the variable source prod-
MATERIALS AND METHODS Birds and Management Two separate experiments were conducted using the same protocol. Male broiler chicks (Ross 708) were purchased from a local hatchery and were individually tagged with identification numbers. Birds were provided ad libitum access to water and the same
C 2016 Poultry Science Association Inc. Received February 23, 2016. Accepted May 27, 2016. 1 Corresponding author: [email protected]
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determined by the regression method. The DM of CM, CSM, BM and PFM were 883, 878, 878, and 964 g/kg, respectively and the respective gross energies (GE) were 4,143, 4,237, 4,060, and 5,783 kcal/kg DM. In Exp. 1, the IDE were 2,132 and 2,197 kcal/kg DM for CM and CSM, respectively. The ME were 2,286 and 2,568 kcal/kg DM for CM and CSM, respectively. The MEn were 1,931 kcal/kg DM for CM and 2,078 kcal/ kg DM for CSM. In Exp. 2, IDE values were 3,412 kcal/kg DM for BM and 4,801 kcal/kg DM for PFM; ME values were 3,176 and 4,601 kcal/kg DM for BM and PFM, respectively, and the MEn values were 3,093 kcal/kg DM for BM and 4,112 kcal/kg DM for PFM. In conclusion, the current study showed that chickens can utilize a considerable amount of energy from these 4 ingredients, and also provided the energy values of CM, CSM, BM and PFM for broiler chickens.
ABSTRACT The energy values of canola meal (CM), cottonseed meal (CSM), bakery meal (BM), and peanut flour meal (PFM) for broiler chickens were determined in 2 experiments with Ross 708 broiler chickens from d 21 to 28 posthatch. The birds were fed a standard broiler starter diet from d 0 to 21 posthatch. In each experiment, 320 birds were grouped by weight into 8 blocks of 5 cages with 8 birds per cage and assigned to 5 diets. Each experiment used a corn-soybean meal reference diet and 4 test diets in which test ingredients partly replaced the energy sources in the reference diet. The test diets in Exp. 1 consisted of 125 g CM, 250 g CM, 100 g CSM, or 200 g CSM/kg. In Exp. 2, the test diets consisted of 200 g BM, 400 g BM, 100 g PFM, or 200 g PFM/kg. The ileal digestible energy (IDE), metabolizable energy (ME), and nitrogen-corrected metabolizable energy (MEn ) of all the test ingredients were
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ZHANG AND ADEOLA Table 1. Ingredient composition of starter diets fed from d 0 to 21 post hatch and experimental diets (reference and test diets) fed from d 21 to 28 posthatch in Exp. 1. d 21 to 28 Test diets
Item
Reference diet
Canola meal
Cottonseed meal
Starter diet
0
125
250
100
200
545.2 360.0 50.0 15.0 15.0 4.0 3.0 3.8 2.9 1.1 0.0 0.0 0.0
520.2 360.0 50.0 15.0 15.0 4.0 3.0 3.8 2.9 1.1 25.0 0.0 0.0
449.2 312.6 43.4 15.0 15.0 4.0 3.0 3.8 2.9 1.1 25.0 125.0 0.0
378.1 265.3 36.8 15.0 15.0 4.0 3.0 3.8 2.9 1.1 25.0 250.0 0.0
463.4 322.1 44.7 15.0 15.0 4.0 3.0 3.8 2.9 1.1 25.0 0.0 100.0
406.5 284.2 39.5 15.0 15.0 4.0 3.0 3.8 2.9 1.1 25.0 0.0 200.0
227 3,153 8.7 6.9 4.4
228 3,110 9.3 6.9 4.4
254 2952 10.0 7.9 4.6
280 2793 10.7 8.8 4.8
247 3023 9.3 7.6 4.5
265 2936 9.4 8.2 4.7
14.6 5.9 9.2 18.9 14.3 7.2 10.8 10.5 19.2 9.4 3.0 10.2
14.6 5.9 9.2 18.9 14.3 7.2 10.7 10.5 19.1 9.4 3.0 10.2
15.5 6.3 10.0 19.8 15.4 7.7 16.7 11.1 20.0 10.3 3.2 11.3
16.4 6.7 10.7 20.8 16.5 8.1 17.7 11.7 20.9 11.3 3.4 12.4
17.6 6.3 9.6 19.4 15.0 7.5 14.1 11.6 20.4 9.9 3.0 11.0
20.6 6.8 10.1 19.9 15.6 7.8 14.7 12.6 21.7 10.5 3.0 11.9
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16% Ca, 21% P. Supplied the following per kilogram diet: vitamin A, 5,484 IU; vitamin D3 , 2,643 IU; vitamin E, 11 IU; menadione sodium bisulfite, 4 mg; riboflavin, 5 mg; D-pantothenic acid, 11 mg; niacin, 44 mg; choline chloride, 771 mg; vitamin B12 , 13 μ g; biotin, 55 μ g; thiamine mononitrate, 2 mg; folic acid, 990 μ g; pyridoxine hydrochloride, 3 mg; I, 1 mg; Mn, 66 mg; Cu, 4 mg; Fe, 44 mg; Zn, 44 mg; Se, 300 μ g. 3 Prepared as 1 g of chromic oxide added to 4 g of ground corn. 2
standard starter broiler diet (Table 1) from d 0 to 21 posthatch for 2 experiments. Birds were reared in electrically heated battery brooders and the temperature was kept at 35◦ C, 31◦ C and 27◦ C from d 0 to 7, d 7 to 14, and d 14 to 28 posthatch, respectively with 23 h light:1 h darkness. In Exp. 1, the average body weight (BW) of d 0 and d 21 posthatch were 35 and 752 g, respectively, and 21-d feed intake was 909 g. For Exp. 2, the average BW of d 0 posthatch and d 21 posthatch were 46 and 797 g respectively, and 21-d feed intake was 982 g. On d 21, 320 birds were sorted by weight and allocated to 5 experimental diets for Exp. 1 (Table 1) and 2 (Table 2). The birds were allocated to experimental diets in such a way that the initial BW was not different across diets. Each experimental diet was replicated 8 times with 8 birds per replicate cage for each of the experiments. On d 28 posthatch, birds were weighed individually and feeder weight per cage was recorded. Excreta were collected twice daily from d 24 to 27 posthatch. Dur-
ing collection, waxed paper was placed under the cages and excreta on the waxed paper were collected. The collected excreta samples were pooled per cage over a 3-d period and stored in a freezer at –20◦ C until dried and ground for analyses. On d 28 posthatch, feeders and birds were weighed to determine BW gain and feed intake. All the birds were euthanized by CO2 asphyxiation. Ileal digesta was collected from the Meckel’s diverticulum to approximately 2 cm cranial to the ileocecal junction. Ileal contents from birds in the same cage were flushed with distilled water into plastic containers and stored at –20◦ C until dried and ground. All protocols used in the study were approved by the Purdue University Animal Care and Use Committee.
Test Ingredients and Experimental Diets The analyzed gross energy (GE) and chemical composition of CM, CSM, BM and PFM are presented in
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Ingredient, g/kg Corn Soybean meal (48% CP) Soybean oil Monocalcium phosphate1 Limestone (38% Ca) Salt Vitamin-mineral premix2 DL-Methionine L-Lysine HCl (99%) L-Threonine Corn-chromic oxide premix 3 Canola meal Cottonseed meal Calculated nutrient content, g/kg CP ME, kcal/kg Ca P Nonphytate P Total amino acids Arg His Ile Leu Lys Met Met + Cys Phe Phe + Tyr Thr Trp Val
d 0 to 21
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ENERGY VALUES OF BROILER FEED INGREDIENTS Table 2. Ingredient composition of test diets fed from d 21 to 28 posthatch in Exp. 2.1 d 21 to 28 Test diets Bakery meal
Peanut flour meal
200
400
100
200
Ingredient, g/kg Corn Soybean meal (48% CP) Soybean oil Monocalcium phosphate2 Limestone (38% Ca) Salt Vitamin-mineral premix3 DL- Methionine L-Lysine.HCL (99%) L-Threonine Corn-chromic oxide premix4 Canola meal Cottonseed meal
406.5 284.2 39.5 15.0 15.0 4.0 3.0 3.8 2.9 1.1 25.0 200.0 0.0
292.8 208.4 29.0 15.0 15.0 4.0 3.0 3.8 2.9 1.1 25.0 400.0 0.0
463.4 322.1 44.7 15.0 15.0 4.0 3.0 3.8 2.9 1.1 25.0 0.0 100.0
406.5 284.2 39.5 15.0 15.0 4.0 3.0 3.8 2.9 1.1 25.0 0.0 200.0
Calculated nutrient content, g/kg CP 205 ME, kcal/kg 3296 Ca 9.6 P 6.9 Nonphytate P 4.6
183 3482 9.9 6.8 4.9
252 3381 9.2 7.0 4.4
276 3652 9.2 7.1 4.4
10.6 4.5 7.1 14.6 11.0 6.7 10.3 8.4 14.9 7.4 2.3 8.1
18.1 6.3 9.9 19.9 14.2 7.3 11.1 11.8 21.3 9.7 3.1 11.1
21.6 6.8 10.6 21.0 14.1 7.5 11.5 13.1 23.5 10.0 3.3 12.0
Total amino acids Arg His Ile Leu Lys Met Met + Cys Phe Phe + Tyr Thr Trp Val
12.6 5.2 8.1 16.7 12.6 7.0 10.5 9.5 17.0 8.4 2.7 9.1
1 The same starter diet in Exp. 1 was fed from d 0 to 21 posthatch, and the same reference diet in Exp. 1 was fed from d 21 to 28 posthatch in Exp. 2 2 16% Ca, 21% P. 3 Supplied the following per kilogram diet: vitamin A, 5,484 IU; vitamin D3 , 2,643 IU; vitamin E, 11 IU; menadione sodium bisulfite, 4 mg; riboflavin, 5 mg; D-pantothenic acid, 11 mg; niacin, 44 mg; choline chloride, 771 mg; vitamin B12 , 13 μ g; biotin, 55 μ g; thiamine mononitrate, 2 mg; folic acid, 990 μ g; pyridoxine hydrochloride, 3 mg; I, 1 mg; Mn, 66 mg; Cu, 4 mg; Fe, 44 mg; Zn, 44 mg; Se, 300 μ g. 4 Prepared as 1 g of chromic oxide added to 4 g of ground corn.
Table 3. Experimental diets consisted of a corn-SBM reference diet and 2 test diets for each of the experiments. Corn, SBM, and soy oil were used as the energy sources in the reference diet (Table 1). The CM was added at 125 or 250 g/kg, and CSM at 100 or 200 g/kg of diet to partly replace the energy sources in test diets, so that the ratio of corn, SBM, and soy oil across the experimental diets were maintained the same in Exp. 1. These ratios were 1.50, 10.80, and 7.20 for corn:SBM, corn:soy oil, and SBM:soy oil, respectively for the experimental diets fed from d 21 to 28 in Table 1. In Exp. 2 (Table 2), BM was added at 200 or 400 g/kg, and PFM at 100 or 200 g/kg of diet to partly replace corn, SBM, and soy oil to maintain the same ratio of corn:SBM, corn:soy oil, and SBM:soy oil as in Exp. 1. All the diets were fed as mash in current study.
Chemical Analyses Excreta and ileal digesta samples were placed in a forced-air oven at 55◦ C for 96 h and subsequently ground to pass through a 0.5-mm screen in a grinder (Retsch ZM 100, GmbH & Co. K. C., Haan, Germany) to ensure a homogeneous mixture. Diets, test ingredients, excreta and ileal digesta were analyzed for dry matter (DM) by drying in an oven overnight (Precision Scientific Co., Chicago, IL) at 105◦ C. The GE was determined in a bomb calorimeter (Parr 1261 bomb calorimeter, Parr Instruments Co., Moline, IL) using benzoic acid as a standard. Nitrogen was determined using the combustion method (Leco model TruMac N analyzer, Leco Corp., St. Joseph, Michigan) using ethylenediaminetetraacetic acid as a calibration
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Item
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ZHANG AND ADEOLA
standard. All the samples were digested [nitric/perchloric wet ash, method 935.13 A (a); AOAC International, 2000] and Cr concentrations were determined (Spectronic 21D, Milton Roy Company, Rochester, NY) using the method of Fenton and Fenton (1979). The test ingredients were analyzed for crude fat [AOAC Official Method 920.39], crude fiber [AOAC Official Method 978.10], acid detergent fiber, and neutral detergent fiber [AOAC Official Method 973.18 (A-D)]. The Ca and P [AOAC Official Method 985.01 (A, B, D)] of ingredients were analyzed as well.
Calculations and Statistics
RESULTS The analyzed nutrients and energy composition of the CM, CSM, BM, and PFM are presented in Table 3. It shows that CM, CSM, and BM have similar CP compared with NRC (1994), but lower crude fat. Among these ingredients, PFM has a highest CP, as well as GE because of high concentration of oil. In Exp. 1, quadratic effect was observed on final BW, weight gain, and gain/feed by adding CSM into the reference diet (Table 4). In Table 5, the DM and energy metabolizability coefficient, IDE, ME, and MEn values
Table 3. Chemical composition of the test ingredients evaluated in Exp. 1 and 2 on an as-is basis. Item, g/kg
Canola meal Cottonseed meal Bakery meal Peanut flour meal
DM Gross energy, kcal/kg Nitrogen Calcium Phosphorus Crude fat Crude fiber Acid detergent fiber Neutral detergent fiber Ash
883 4,143 65.4 7.1 11.0 10.5 11.6 16.2 21.7 8.1
878 4,237 67.4 2.3 10.2 8.4 13.1 16.1 24.6 7.7
878 4,060 19.4 2.7 3.8 54.1 0.9 2.9 6.6 5.8
964 5,783 75.6 0.9 4.8 278.9 1.3 2.1 5.7 3.4
Indispensable amino acids Arg His Ile Leu Lys Met Phe Thr Trp Val
22.5 9.7 15.7 27.5 21.6 7.4 16.1 16.2 4.7 19.8
45.2 11.0 14.0 25.2 19.3 6.7 21.8 14.0 3.0 19.4
5.4 2.8 4.4 9.2 4.3 2.4 5.9 3.8 1.5 5.6
50.4 10.8 16.8 30.6 11.7 5.0 24.1 11.7 4.7 20.0
Dispensable amino acids Ala Asp Cys Glu Gly Pro Tyr Ser
16.7 26.7 8.6 65.5 19.3 24.1 11.0 14.3
16.9 38.0 6.6 80.6 17.7 16.3 11.5 17.6
5.1 6.9 2.1 31.0 5.2 10.4 3.6 5.1
17.9 52.2 5.1 85.5 27.1 18.2 17.9 18.2
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The ileal digestibility and total tract metabolizability coefficients (C) of nutrients and energy were calculated as previously reported (Bolarinwa and Adeola, 2012). The product of C and GE concentration (kcal/kg) of the diet were used to calculate the IDE, ME, and MEn. The definition that the test diet energy consists of energy from reference diet and the energy from test ingredient make the sum of proportional contribution of energy of the reference diet and the test ingredient equal to 1: Prd + Pti = 1, where Prd and Pti represent proportion of energy contribution from reference diet and test ingredient, respectively. The coefficients of ME for reference diet, test diets, and test ingredients are Crd , Ctd , and Cti , respectively. The assumption of additivity in diet formulation gives: Ctd = (Crd × Prd ) + (Cti ×
Pti ); solving for Cti gives: Cti = [Ctd − (Crd × Prd )] / Pti ; substituting 1 − Pti for Prd gives: Cti = [Crd + (Ctd − Crd )/Pti ]. The GLM procedure of SAS (SAS, 1989) was used to analyze growth performance and digestibility data for the 2 experiments in a randomized complete block design as previously described (Bolarinwa and Adeola, 2012). The effects of increasing levels of CM or CSM in test diets in Exp. 1 and BM or PFM in test diets in Exp. 2 were compared using linear and quadratic contrasts. Regression of the test ingredient-associated IDE, ME, or MEn intake in kilocalories against kilograms of test ingredient intake for cage of birds was conducted using multiple linear regression for each experiment using the SAS statements described by Bolarinwa and Adeola (2012). Statistical significance was determined at an α level of 0.05.
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ENERGY VALUES OF BROILER FEED INGREDIENTS Table 4. Growth performance of birds fed experimental diets from d 21 to 28 posthatch in Exp. 1 and 2.1 P – value Item Exp. 1
Initial BW, g Final BW, g Weight gain, g Feed intake, g G:F, g:kg Exp. 2
Reference diet
125 g/kg canola meal
250 g/kg canola meal
774 1,249 475 698 679
774 1,263 489 713 684
773 1,243 470 672 698
Reference diet
200 g/kg bakery meal
400 g/kg bakery meal
814 1,348 534 768 700
812 1,325 512 768 668
812 1,309 497 772 650
L2
Q2
L3
Q3
100 g/kg cottonseed meal 774 1,312 539 748 718
200 g/kg cottonseed meal 774 1,234 460 710 650
0.5 24.2 24.3 29.0 19.4
0.337 0.882 0.894 0.540 0.486
0.577 0.576 0.582 0.434 0.845
0.747 0.681 0.671 0.768 0.298
0.710 0.023 0.023 0.216 0.033
100 g/kg peanut flour meal 814 1,320 506 765 662
200 g/kg peanut flour meal 813 1,314 501 742 677
0.7 19.4 19.6 24.6 29.1
0.977 0.489 0.161 0.918 0.222
0.983 0.933 0.900 0.963 0.852
0.985 0.547 0.218 0.474 0.576
0.994 0.815 0.608 0.763 0.451
1
Data are means of 8 replicate cages with 8 birds per cage. Linear (L) and quadratic (Q) contrasts for canola meal in Exp. 1 and bakery meal in Exp. 2, respectively. 3 Linear (L) and quadratic (Q) contrasts for cottonseed meal in Exp. 1 and peanut flour meal in Exp. 2, respectively. 2
Table 5. Ileal digestibility and total tract utilization of DM, nitrogen, and energy of birds fed experimental diets from d 21 to 28 posthatch in Exp. 1 and 2.1 P – value Item Exp. 1 Ileal digestibility DM Energy IDE, kcal/kg DM Total tract metabolizability DM coefficient Energy, N-corrected energy ME, kcal/kg DM MEn , kcal/kg DM Exp. 2 Ileal digestibility DM Energy IDE, kcal/kg DM Total tract metabolizability DM coefficient Energy, N-corrected energy ME, kcal/kg DM MEn , kcal/kg DM
SD
L2
Q2
L3
Q3
Reference diet
125 g/kg canola meal
250 g/kg canola meal
100 g/kg cottonseed meal
200 g/kg cottonseed meal
0.760 0.783 3,645
0.729 0.757 3,470
0.677 0.717 3,365
0.726 0.761 3,596
0.697 0.729 3,417
0.024 0.023 0.109
< 0.001 < 0.001 < 0.001
0.328 0.497 0.466
< 0.001 < 0.001 < 0.001
0.845 0.619 0.178
0.729 0.772 0.715 3,596 3,329
0.703 0.744 0.685 3,411 3,142
0.666 0.721 0.656 3,386 3,079
0.709 0.759 0.699 3,588 3,303
0.687 0.735 0.667 3,443 3,129
0.020 0.018 0.016 0.083 0.076
< 0.001 < 0.001 < 0.001 < 0.001 < 0.001
0.525 0.715 0.981 0.035 0.073
< 0.001 < 0.001 < 0.001 0.001 < 0.001
0.885 0.450 0.288 0.067 0.034
Reference diet
200 g/kg bakery meal
400 g/kg bakery meal
100 g/kg peanut flour meal
200 g/kg peanut flour meal
0.791 0.838 3,963
0.775 0.824 3,832
0.790 0.833 3,862
0.769 0.828 4,020
0.768 0.833 4,212
0.020 0.017 0.076
0.956 0.076 0.025
0.525 0.086 0.495
0.007 0.012 < 0.001
0.956 0.076 0.025
0.718 0.773 0.729 3,659 3,451
0.710 0.762 0.724 3,545 3,364
0.726 0.776 0.742 3,598 3,438
0.715 0.777 0.725 3,769 3,520
0.701 0.774 0.721 3,913 3,648
0.031 0.028 0.023 0.133 0.105
0.605 0.834 0.257 0.337 0.786
0.350 0.285 0.201 0.131 0.072
0.232 0.980 0.436 < 0.001 < 0.001
0.687 0.782 0.995 0.759 0.503
1 Data are means of 8 replicate cages with 8 birds per cage, but one IDE value and one ME value were missing in 100 g/kg canola meal treatment in Exp. 1. 2 Linear (L) and quadratic (Q) contrasts for canola meal in Exp. 1 and bakery meal in Exp. 2, respectively. 3 Linear (L) and quadratic (Q) contrasts for cottonseed meal in Exp. 1 and peanut flour meal in Exp. 2, respectively.
were higher in the reference diet compared with test diets. Linear effects were observed on DM digestibility in the diets containing either CM or CSM. Also, there was a linear decrease (P < 0.01) in diet energy digestibility with increasing levels of CM or CSM, and a similar pattern was observed in DM and energy me-
tabolizability. Quadratic effect was also observed in the diets containing CM. Nitrogen correction resulted in a 7% reduction in ME of reference diet, and an average of 8.5% reduction in ME of either CM diets or CSM diets. As seen with ME, there was a linear decrease in MEn of diets containing either CM or CSM.
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Initial BW, g Final BW, g Weight gain, g Feed intake, g G:F, g:kg
SEM
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ZHANG AND ADEOLA Table 6. Regression equations relating test ingredient-associated energy intake to intake of canola meal (CM) or cottonseed meal (CSM) in Exp. 1 and bakery meal (BM) or peanut flour meal (PFM) in Exp. 2.1 Item Exp. 1 IDE ME MEn Exp. 2 IDE ME MEn
r2
SD
Y = 9 (14) + 2,132 (143) × CM + 2,197 (171) × CSM Y = –0.3 (14) + 2,286 (151) × CM + 2,568 (180) × CSM Y = 6 (14) + 1,931 (150) × CM + 2,078 (178) × CSM
0.88 0.88 0.84
48 48 48
Y = –14 (11) + 3,412 (111) × BM + 4,801 (131) × PFM Y = –7 (13) + 3,176 (125) × BM + 4,601 (148) × PFM Y = –8 (10) + 3,093 (96) × BM + 4,112 (114) × PFM
0.98 0.97 0.98
40 45 35
Regression equation
1 Values in parentheses are SE; Y is in kilocalories, intercept is in kilocalories, and the slopes are in kilocalories/kg of DM.
DISCUSSION Many alternative ingredients have been used to replace corn and SBM to meet the animals’ dietary nutrients requirements with proper formulation (Fernandez et al., 1994). An accurate determination of alternative ingredients nutrients and energy value will help to formulate a proper diet and satisfy animal requirements (Bolarinwa and Adeola, 2012). In current study, CM, CSM, BM, and PFM were chosen to determine energy value for broiler chickens. Canola meal has less digestible energy and protein, and more glucosinolates compared with SBM (Slominski and Campbell, 1991). In the current study, the inclusion of CM did not affect growth performance, which agrees with previous report that there was no significant effect of partially replacing SBM with CM on growth performance of broilers. One possible explanation is that when the inclusion level of CM was low, CM with an average of 3.9 μmol/g glucosinolates contributed only small amount of antinutrients into the diets, which would have limited effects on growth performance, considering a 4 μmol/g of diet as the max-
imum level of glucosinolates inclusion rate for broilers (Khajali and Slominski, 2012). However, in CSM diets, there was a quadratic effect on final BW, weight gain, and G:F by adding CSM, which is consistent with previous findings that incorporation of 150 g/kg CSM in broiler diets depressed BW and feed intake (El-Boushy and Raterink, 1989). This depression of BW and feed intake may be caused by several factors. First, the CSM protein is deficient in essential amino acids, such as Met, Lys, Thr, and Val (Fernandez et al., 1995). In addition, the digestibility of amino acids in CSM is also low, due to high concentration of cell-wall constituents, which leads to faster passage rate of digesta in small intestine (Sandal, 1974; Nagalakshmi et al., 2007). Another reason is due to the free gossypol in CSM. The concentration of free gossypol in CSM varies from 200 to 5,300 mg/kg (Nagalakshmi et al., 2007), and can have direct inhibitory action on certain enzymes such as pepsinogen, pepsin, and trypsin in the avian gastrointestinal tract. Also, gossypol can combine with the free epsilon amino group of Lys, and lead to peptides unavailable to the proteolytic action, hence further decreasing the digestibility of protein (Sharma et al., 1978). In the current experiment, the digestibility of DM and energy were depressed by adding CM and CSM. As a result, IDE, ME, and MEn were linearly decreased with the increasing level of CM and CSM. One of the major reasons may due to the high fiber content of CM and CSM (Bell, 1993; Nagalakshmi et al., 2007). When the inclusion of CM and CSM increased, the increased fiber diets may result in a lower protein and energy digestibility (Hetland et al., 2004). Another reason may be due to the anti-nutrients from CM and CSM, such as glucosinolates and gossypol. As described above, those anti-nutrients may also negatively affect energy digestibility. In Exp. 2, adding BM into the test diets did not affect birds growth performance, which agrees with previous findings that inclusion of bakery product in diets at levels up to 25% had no adverse effects on growth performance of broilers (Saleh et al., 1996). The same results were observed for PFM: there was no effect on growth performance of 28 d broilers by adding PFM. Formulating BM into the test diets had no effect on ME,
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In Exp. 2, the inclusion of either BM or PFM to the reference diet did not affect the growth performance of birds from d 21 to 28 posthatch (Table 4). Adding BM linearly decreased IDE, but had no effects on DM and energy metabolizability coefficients, ME, and MEn values. Adding PFM linearly reduced DM and energy digestibility, but increased IDE value. The PFM inclusion had no effects on DM metabolizability, energy metabolizability, and N-corrected energy metabolizability, but linearly increased ME and MEn (P < 0.01). Energy values are shown in Table 6. All values are reported on a DM basis. In Exp. 1, the IDE were 2,132 kcal/kg DM for CM and 2,197 kcal/kg for CSM; the ME were 2,286 kcal/kg DM for CM and 2,568 kcal/kg for CSM; MEn were 1,931 kcal/kg DM for CM and 2,078 kcal/ kg for CSM. In Exp. 2, IDE values were 3,412 kcal/kg DM for BM and 4,801 kcal/kg DM for PFM; ME values were 3,176 kcal/kg DM for BM and 4,601 kcal/kg DM for PFM; MEn values were 3,093 kcal/kg DM for BM and 4,112 kcal/kg DM for PFM.
ENERGY VALUES OF BROILER FEED INGREDIENTS
and 2,078 kcal/kg of DM, respectively. The CSM used in current study is decorticated, which has a higher ME than undecorticated CSM (Sharma et al., 1978). The decorticated CSM has ME ranging from 1,901 to 2,811 kcal/kg, mainly depending on the residual oil content (Nagalakshmi et al., 2007), and our results fall within this range. The ME in current study is more than 300 kcal/kg higher than IDE, the explanation for this is not well understood. One possible explanation is because of the comparatively high fiber contents in CSM, which resulted in the production of short-chain fatty acid in ceca, contributed partly to this energy increment (Annison et al., 1968). The same with CM, the MEn of CSM is also lower than that of SBM, which is also mainly due to the high fiber concentration and anti-nutrients. The determined IDE, ME, and MEn values of BM in current study were 3,412, 3,176, and 3,093 kcal/kg respectively. Dale et al. (1990) reported 36 bakery products with MEn ranging from 3,050 to 3,980 kcal/kg, our result fall within this range. However, NRC (1994) reported a MEn of 3,862 kcal/kg DM of BM, which is higher than the result from current study. Based on the current study, BM can provide a similar amount of energy as corn. As a result, it should be considered as an excellent alternative source of energy in poultry diets. To our knowledge, limited information about available energy of PFM has been published. The IDE, ME, and MEn values of PFM in current study were determined to be 4,801, 4,601, and 4,112 kcal/kg respectively, which is higher than most energy ingredients due to the high oil concentration present in PFM. In conclusion, the current study provided the energy values for these test ingredients and showed that they can provide a considerable amount of energy for broiler chickens. However, as with many byproducts, the nutrients contents vary widely, more data is needed to build up a robust database for broiler chickens.
REFERENCES Almeida, F., G. Petersen, and H. Stein. 2011. Digestibility of amino acids in corn, corn coproducts, and bakery meal fed to growing pigs. J. Anim. Sci. 89:4109–4115. Annison, E. F., K. J. Hill, and R. Kennworthy. 1968. Volatile fatty acids in the digestive tract of the fowl. Br. J. Nutr. 22:207–216. AOAC International. 2000. Official Methods of Analysis. 17th ed. Association of Official Analytical Chemists, Arlington, VA. Bell, J. 1993. Factors affecting the nutritional value of canola meal: a review. Can. J. Anim. Sci. 73:689–697. Bolarinwa, O., and O. Adeola. 2012. Energy value of wheat, barley, and wheat dried distillers grains with solubles for broiler chickens determined using the regression method. Poult. Sci. 91:1928– 1935. Dale, N., G. Pesti, and S. Rogers. 1990. True metabolizable energy of dried bakery product. Poult. Sci. 69:72–75. El-Boushy, A., and R. Raterink. 1989. Replacement of soybean meal by cottonseed meal and peanut meal or both in low energy diets for broilers. Poult. Sci. 68:799–804. Fenton, T. W., and M. Fenton. 1979. An improved procedure for the determination of dietary chromic oxide in feed and feces. Can. J. Anim. Sci. 59:631–634. Fernandez, S. R., S. Aoyagi, Y. Han, C. M. Parsons, and D. H. Baker. 1994. Limiting order of amino acids in corn and soybean meal for growth of the chick. Poult. Sci. 73:1887–1896.
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and MEn , but linearly decreased IDE. Because BM is produced by mixing different available byproducts, the explanation for the decreasing IDE of BM diets is not specifically known. It may be due to the high concentration of non-starch polysaccharides (NSP). There was a high variability of NSP content in bakery meal, ranging from 34 to 170 g/kg. Samples with high NSP may affect available energy (Slominski et al., 2004). In PFM diets, DM and energy digestibility were depressed as the inclusion of PFM increased, but IDE of test diet were increased as PFM increased. The results indicate that the energy digestibility coefficient for PFM derived using the regression method is 0.830, which is lower than the reference diet. Hence, a test ingredient with a lower energy digestibility coefficient will take the place of the more digestible part in reference diet, and will decrease the dietary digestibility. A possible reason for the lower energy digestibility of PFM compared with reference diet is the high phytate content in PFM (Namkung and Leeson 1999; Iyayi et al., 2013). The phytate concentration of the PFM used in current study was analyzed to be 2.78 g/kg, which accounts for 62.6% of total phosphorus. Phytate can form complexes with proteins and reduce protein digestibility, and also interfere with proteases in the gastrointestinal tract to decrease the digestibility of protein and amino acids (Singh and Krikorian, 1982). As a result, the digestibility of energy will be negatively affected. However, because of the high GE content of PFM, the GE of test diets increased as the PFM inclusion level increased, the IDE of test diets still be increased. The same for ME and MEn , metabolizable energy coefficient for PFM derived using the regression method was higher than the reference diet, the GE of test diets is higher than reference diet as well, which led to the linear increase in ME and MEn . In avian species, ME is corrected for nitrogen balance by subtracting 8.22 kcal of ME per g of nitrogen retention from the measured ME values (Hill and Anderson, 1958). In the current study, nitrogen correction resulted in a 15, 19, and 10% reduction for protein sources CM, CSM, and PFM, respectively, and a 4% reduction for BM. Obviously, there was more reduction in ME of protein ingredients than that of BM after nitrogen correction, because more nitrogen was retained in CM, CSM, and PFM groups compared with BM group. The IDE, ME, and MEn values measured in current study using regression method for CM were 2,132, 2,286, and 1,931 kcal/kg of DM, respectively. The average MEn of CM for poultry is 2,000 kcal/kg (NRC, 1994), which is close to the result in current study. The MEn of CM is 230 kcal/kg lower than that of SBM. The main reason for the lower ME of CM may be due to the high dietary fiber content, which could accelerate the digesta passage rate, and consequently reduce the time for digestion and nutrient utilization (Hetland et al., 2004). In addition, comparatively high concentration of anti-nutrients could reduce nutrients utilization and further decrease ME. The IDE, ME, and MEn values of CSM using regression method were 2,197, 2,568,
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ZHANG AND ADEOLA NRC. 1994. Nutrient Requirements of Poultry. 9th rev. ed. Natl. Acad. Press, Washington, DC. Saleh, E., S. Watkins, and P. Waldroup. 1996. High-level usage of dried bakery product in broiler diets. J. Appl. Poult. Res. 5:33–38. Sandal, D. 1974. Rapid method for evaluating metabolizable energy of poultry feeds. M. Sc. Thesis, Punjab Agricultural University, Ludhiana, India. SAS Institute. 1989. SAS/STAT User’s Guide. SAS Institute Inc., Cary, NY. Sharma, N., G. Lodhi, and J. Ichhponani. 1978. Comparative feeding value of expeller-processed undecorticated and decorticated cottonseed cakes for growing chicks. J. Agric. Sci. 91:531–541. Singh, M., and A. Krikorian. 1982. Inhibition of trypsin activity in vitro by phytate. J. Agr. Food. Chem. 30:799–800. Slominski, B. A., D. Boros, L. D. Campbell, W. Guenter, and O. Jones. 2004. Wheat by-products in poultry nutrition. Part I. Chemical and nutritive composition of wheat screenings, bakery by-products and wheat mill run. Can. J. Anim. Sci. 84:421–428. Slominski, B. A., and L. D. Campbell. 1991. Influence of indole glucosinolates on the nutritive quality of canola meal. Pages 396–401 in Proc. 8th Int. Rapeseed Congress, Saskatoon, SK, Canada. Canola Council of Canada, Winnipeg, MA, Canada.
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Fernandez, S. R., Y. Zhang, and C. M. Parsons. 1995. Dietary formulation with cottonseed meal on a total amino acid versus a digestible amino acid basis. Poult. Sci. 74:1168–1179. Hetland, H., M. Choct, and B. Svihus. 2004. Role of insoluble nonstarch polysaccharides in poultry nutrition. World’s Poult. Sci. J. 60:415–422. Heywang, B., and A. Kemmerer. 1966. Effect of gossypol source and level on chick growth. Poult. Sci. 45:1429–1430. Hill, F. W., and D. L. Anderson. 1958. Comparison of metabolizable energy and productive determinations with growing chicks. J. Nutr. 64:587–603. Iyayi, E., F. Fru-Nji, and O. Adeola. 2013. True phosphorus digestibility of black-eyed pea and peanut flour without or with phytase supplementation in broiler chickens. Poult. Sci. 92:1595– 1603. Khajali, F., and B. A. Slominski. 2012. Factors affecting the nutritive value of canola meal for poultry. Poult. Sci. 91:2564–2575. Nagalakshmi, D., S. V. R. Rao, A. K. Panda, and V. R. Sastry. 2007. Cottonseed meal in poultry diets: a review. J. Poult. Sci. 44:119–134. Namkung, H., and S. Leeson. 1999. Effect of phytase enzyme on dietary nitrogen-corrected apparent metabolizable energy and the ileal digestibility of nitrogen and amino acids in broiler chicks. Poult. Sci. 78:1317–1319.
Key words: bakery meal, canola meal, cottonseed meal, metabolizable energy, peanut flour meal 2016 Poultry Science 0:1–8 http://dx.doi.org/10.3382/ps/pew239
INTRODUCTION
ucts and different processing procedures, there is a lot of variability in nutrients and energy contents (Slominski et al., 2004). Peanut flour meal (PFM) is also a good source of plant protein and contains high concentrations of energy, but there is limited data on energy value for broiler chickens. Due to the recent challenges in the poultry industry of feed costs and the potential benefits of using alternative ingredients in broiler chicken diets, more data on the ileal digestible energy (IDE), metabolizable energy (ME) and nitrogen-corrected metabolizable energy (MEn ) are needed to optimize diet formulation. Therefore, the objective of the current study was to determine the IDE, ME, and MEn of CM, CSM, BM, and PFM for broiler chickens using the regression method.
Canola meal (CM) and cottonseed meal (CSM) are the byproducts of the process used to extract oil from canola or cotton seeds, which contain 38 or 41% crude protein (CP), respectively, and considerable amount of energy (NRC, 1994). Those two ingredients are increasingly used in non-ruminant animals diets as proteinsource substitutes for soybean meal (SBM), but are still restricted to partial replacement of SBM because of deficiencies in some essential amino acids (AA), high concentrations of anti-nutrients such as glucosinolates and gossypol, as well as the low available energy content (Heywang and Kemmerer, 1966; Bell, 1993). Bakery meal (BM) is a combination byproduct derived from the baking and cereal industries, such as wheat products, pasta, potato chip waste, cakes, and breakfast cereals (Almeida et al., 2011). The BM is high in fat and carbohydrates, which make it an important energy feedstuff that can be used to partially replace corn in poultry diets. However, due to the variable source prod-
MATERIALS AND METHODS Birds and Management Two separate experiments were conducted using the same protocol. Male broiler chicks (Ross 708) were purchased from a local hatchery and were individually tagged with identification numbers. Birds were provided ad libitum access to water and the same
C 2016 Poultry Science Association Inc. Received February 23, 2016. Accepted May 27, 2016. 1 Corresponding author: [email protected]
1
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determined by the regression method. The DM of CM, CSM, BM and PFM were 883, 878, 878, and 964 g/kg, respectively and the respective gross energies (GE) were 4,143, 4,237, 4,060, and 5,783 kcal/kg DM. In Exp. 1, the IDE were 2,132 and 2,197 kcal/kg DM for CM and CSM, respectively. The ME were 2,286 and 2,568 kcal/kg DM for CM and CSM, respectively. The MEn were 1,931 kcal/kg DM for CM and 2,078 kcal/ kg DM for CSM. In Exp. 2, IDE values were 3,412 kcal/kg DM for BM and 4,801 kcal/kg DM for PFM; ME values were 3,176 and 4,601 kcal/kg DM for BM and PFM, respectively, and the MEn values were 3,093 kcal/kg DM for BM and 4,112 kcal/kg DM for PFM. In conclusion, the current study showed that chickens can utilize a considerable amount of energy from these 4 ingredients, and also provided the energy values of CM, CSM, BM and PFM for broiler chickens.
ABSTRACT The energy values of canola meal (CM), cottonseed meal (CSM), bakery meal (BM), and peanut flour meal (PFM) for broiler chickens were determined in 2 experiments with Ross 708 broiler chickens from d 21 to 28 posthatch. The birds were fed a standard broiler starter diet from d 0 to 21 posthatch. In each experiment, 320 birds were grouped by weight into 8 blocks of 5 cages with 8 birds per cage and assigned to 5 diets. Each experiment used a corn-soybean meal reference diet and 4 test diets in which test ingredients partly replaced the energy sources in the reference diet. The test diets in Exp. 1 consisted of 125 g CM, 250 g CM, 100 g CSM, or 200 g CSM/kg. In Exp. 2, the test diets consisted of 200 g BM, 400 g BM, 100 g PFM, or 200 g PFM/kg. The ileal digestible energy (IDE), metabolizable energy (ME), and nitrogen-corrected metabolizable energy (MEn ) of all the test ingredients were
2
ZHANG AND ADEOLA Table 1. Ingredient composition of starter diets fed from d 0 to 21 post hatch and experimental diets (reference and test diets) fed from d 21 to 28 posthatch in Exp. 1. d 21 to 28 Test diets
Item
Reference diet
Canola meal
Cottonseed meal
Starter diet
0
125
250
100
200
545.2 360.0 50.0 15.0 15.0 4.0 3.0 3.8 2.9 1.1 0.0 0.0 0.0
520.2 360.0 50.0 15.0 15.0 4.0 3.0 3.8 2.9 1.1 25.0 0.0 0.0
449.2 312.6 43.4 15.0 15.0 4.0 3.0 3.8 2.9 1.1 25.0 125.0 0.0
378.1 265.3 36.8 15.0 15.0 4.0 3.0 3.8 2.9 1.1 25.0 250.0 0.0
463.4 322.1 44.7 15.0 15.0 4.0 3.0 3.8 2.9 1.1 25.0 0.0 100.0
406.5 284.2 39.5 15.0 15.0 4.0 3.0 3.8 2.9 1.1 25.0 0.0 200.0
227 3,153 8.7 6.9 4.4
228 3,110 9.3 6.9 4.4
254 2952 10.0 7.9 4.6
280 2793 10.7 8.8 4.8
247 3023 9.3 7.6 4.5
265 2936 9.4 8.2 4.7
14.6 5.9 9.2 18.9 14.3 7.2 10.8 10.5 19.2 9.4 3.0 10.2
14.6 5.9 9.2 18.9 14.3 7.2 10.7 10.5 19.1 9.4 3.0 10.2
15.5 6.3 10.0 19.8 15.4 7.7 16.7 11.1 20.0 10.3 3.2 11.3
16.4 6.7 10.7 20.8 16.5 8.1 17.7 11.7 20.9 11.3 3.4 12.4
17.6 6.3 9.6 19.4 15.0 7.5 14.1 11.6 20.4 9.9 3.0 11.0
20.6 6.8 10.1 19.9 15.6 7.8 14.7 12.6 21.7 10.5 3.0 11.9
1
16% Ca, 21% P. Supplied the following per kilogram diet: vitamin A, 5,484 IU; vitamin D3 , 2,643 IU; vitamin E, 11 IU; menadione sodium bisulfite, 4 mg; riboflavin, 5 mg; D-pantothenic acid, 11 mg; niacin, 44 mg; choline chloride, 771 mg; vitamin B12 , 13 μ g; biotin, 55 μ g; thiamine mononitrate, 2 mg; folic acid, 990 μ g; pyridoxine hydrochloride, 3 mg; I, 1 mg; Mn, 66 mg; Cu, 4 mg; Fe, 44 mg; Zn, 44 mg; Se, 300 μ g. 3 Prepared as 1 g of chromic oxide added to 4 g of ground corn. 2
standard starter broiler diet (Table 1) from d 0 to 21 posthatch for 2 experiments. Birds were reared in electrically heated battery brooders and the temperature was kept at 35◦ C, 31◦ C and 27◦ C from d 0 to 7, d 7 to 14, and d 14 to 28 posthatch, respectively with 23 h light:1 h darkness. In Exp. 1, the average body weight (BW) of d 0 and d 21 posthatch were 35 and 752 g, respectively, and 21-d feed intake was 909 g. For Exp. 2, the average BW of d 0 posthatch and d 21 posthatch were 46 and 797 g respectively, and 21-d feed intake was 982 g. On d 21, 320 birds were sorted by weight and allocated to 5 experimental diets for Exp. 1 (Table 1) and 2 (Table 2). The birds were allocated to experimental diets in such a way that the initial BW was not different across diets. Each experimental diet was replicated 8 times with 8 birds per replicate cage for each of the experiments. On d 28 posthatch, birds were weighed individually and feeder weight per cage was recorded. Excreta were collected twice daily from d 24 to 27 posthatch. Dur-
ing collection, waxed paper was placed under the cages and excreta on the waxed paper were collected. The collected excreta samples were pooled per cage over a 3-d period and stored in a freezer at –20◦ C until dried and ground for analyses. On d 28 posthatch, feeders and birds were weighed to determine BW gain and feed intake. All the birds were euthanized by CO2 asphyxiation. Ileal digesta was collected from the Meckel’s diverticulum to approximately 2 cm cranial to the ileocecal junction. Ileal contents from birds in the same cage were flushed with distilled water into plastic containers and stored at –20◦ C until dried and ground. All protocols used in the study were approved by the Purdue University Animal Care and Use Committee.
Test Ingredients and Experimental Diets The analyzed gross energy (GE) and chemical composition of CM, CSM, BM and PFM are presented in
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Ingredient, g/kg Corn Soybean meal (48% CP) Soybean oil Monocalcium phosphate1 Limestone (38% Ca) Salt Vitamin-mineral premix2 DL-Methionine L-Lysine HCl (99%) L-Threonine Corn-chromic oxide premix 3 Canola meal Cottonseed meal Calculated nutrient content, g/kg CP ME, kcal/kg Ca P Nonphytate P Total amino acids Arg His Ile Leu Lys Met Met + Cys Phe Phe + Tyr Thr Trp Val
d 0 to 21
3
ENERGY VALUES OF BROILER FEED INGREDIENTS Table 2. Ingredient composition of test diets fed from d 21 to 28 posthatch in Exp. 2.1 d 21 to 28 Test diets Bakery meal
Peanut flour meal
200
400
100
200
Ingredient, g/kg Corn Soybean meal (48% CP) Soybean oil Monocalcium phosphate2 Limestone (38% Ca) Salt Vitamin-mineral premix3 DL- Methionine L-Lysine.HCL (99%) L-Threonine Corn-chromic oxide premix4 Canola meal Cottonseed meal
406.5 284.2 39.5 15.0 15.0 4.0 3.0 3.8 2.9 1.1 25.0 200.0 0.0
292.8 208.4 29.0 15.0 15.0 4.0 3.0 3.8 2.9 1.1 25.0 400.0 0.0
463.4 322.1 44.7 15.0 15.0 4.0 3.0 3.8 2.9 1.1 25.0 0.0 100.0
406.5 284.2 39.5 15.0 15.0 4.0 3.0 3.8 2.9 1.1 25.0 0.0 200.0
Calculated nutrient content, g/kg CP 205 ME, kcal/kg 3296 Ca 9.6 P 6.9 Nonphytate P 4.6
183 3482 9.9 6.8 4.9
252 3381 9.2 7.0 4.4
276 3652 9.2 7.1 4.4
10.6 4.5 7.1 14.6 11.0 6.7 10.3 8.4 14.9 7.4 2.3 8.1
18.1 6.3 9.9 19.9 14.2 7.3 11.1 11.8 21.3 9.7 3.1 11.1
21.6 6.8 10.6 21.0 14.1 7.5 11.5 13.1 23.5 10.0 3.3 12.0
Total amino acids Arg His Ile Leu Lys Met Met + Cys Phe Phe + Tyr Thr Trp Val
12.6 5.2 8.1 16.7 12.6 7.0 10.5 9.5 17.0 8.4 2.7 9.1
1 The same starter diet in Exp. 1 was fed from d 0 to 21 posthatch, and the same reference diet in Exp. 1 was fed from d 21 to 28 posthatch in Exp. 2 2 16% Ca, 21% P. 3 Supplied the following per kilogram diet: vitamin A, 5,484 IU; vitamin D3 , 2,643 IU; vitamin E, 11 IU; menadione sodium bisulfite, 4 mg; riboflavin, 5 mg; D-pantothenic acid, 11 mg; niacin, 44 mg; choline chloride, 771 mg; vitamin B12 , 13 μ g; biotin, 55 μ g; thiamine mononitrate, 2 mg; folic acid, 990 μ g; pyridoxine hydrochloride, 3 mg; I, 1 mg; Mn, 66 mg; Cu, 4 mg; Fe, 44 mg; Zn, 44 mg; Se, 300 μ g. 4 Prepared as 1 g of chromic oxide added to 4 g of ground corn.
Table 3. Experimental diets consisted of a corn-SBM reference diet and 2 test diets for each of the experiments. Corn, SBM, and soy oil were used as the energy sources in the reference diet (Table 1). The CM was added at 125 or 250 g/kg, and CSM at 100 or 200 g/kg of diet to partly replace the energy sources in test diets, so that the ratio of corn, SBM, and soy oil across the experimental diets were maintained the same in Exp. 1. These ratios were 1.50, 10.80, and 7.20 for corn:SBM, corn:soy oil, and SBM:soy oil, respectively for the experimental diets fed from d 21 to 28 in Table 1. In Exp. 2 (Table 2), BM was added at 200 or 400 g/kg, and PFM at 100 or 200 g/kg of diet to partly replace corn, SBM, and soy oil to maintain the same ratio of corn:SBM, corn:soy oil, and SBM:soy oil as in Exp. 1. All the diets were fed as mash in current study.
Chemical Analyses Excreta and ileal digesta samples were placed in a forced-air oven at 55◦ C for 96 h and subsequently ground to pass through a 0.5-mm screen in a grinder (Retsch ZM 100, GmbH & Co. K. C., Haan, Germany) to ensure a homogeneous mixture. Diets, test ingredients, excreta and ileal digesta were analyzed for dry matter (DM) by drying in an oven overnight (Precision Scientific Co., Chicago, IL) at 105◦ C. The GE was determined in a bomb calorimeter (Parr 1261 bomb calorimeter, Parr Instruments Co., Moline, IL) using benzoic acid as a standard. Nitrogen was determined using the combustion method (Leco model TruMac N analyzer, Leco Corp., St. Joseph, Michigan) using ethylenediaminetetraacetic acid as a calibration
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Item
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ZHANG AND ADEOLA
standard. All the samples were digested [nitric/perchloric wet ash, method 935.13 A (a); AOAC International, 2000] and Cr concentrations were determined (Spectronic 21D, Milton Roy Company, Rochester, NY) using the method of Fenton and Fenton (1979). The test ingredients were analyzed for crude fat [AOAC Official Method 920.39], crude fiber [AOAC Official Method 978.10], acid detergent fiber, and neutral detergent fiber [AOAC Official Method 973.18 (A-D)]. The Ca and P [AOAC Official Method 985.01 (A, B, D)] of ingredients were analyzed as well.
Calculations and Statistics
RESULTS The analyzed nutrients and energy composition of the CM, CSM, BM, and PFM are presented in Table 3. It shows that CM, CSM, and BM have similar CP compared with NRC (1994), but lower crude fat. Among these ingredients, PFM has a highest CP, as well as GE because of high concentration of oil. In Exp. 1, quadratic effect was observed on final BW, weight gain, and gain/feed by adding CSM into the reference diet (Table 4). In Table 5, the DM and energy metabolizability coefficient, IDE, ME, and MEn values
Table 3. Chemical composition of the test ingredients evaluated in Exp. 1 and 2 on an as-is basis. Item, g/kg
Canola meal Cottonseed meal Bakery meal Peanut flour meal
DM Gross energy, kcal/kg Nitrogen Calcium Phosphorus Crude fat Crude fiber Acid detergent fiber Neutral detergent fiber Ash
883 4,143 65.4 7.1 11.0 10.5 11.6 16.2 21.7 8.1
878 4,237 67.4 2.3 10.2 8.4 13.1 16.1 24.6 7.7
878 4,060 19.4 2.7 3.8 54.1 0.9 2.9 6.6 5.8
964 5,783 75.6 0.9 4.8 278.9 1.3 2.1 5.7 3.4
Indispensable amino acids Arg His Ile Leu Lys Met Phe Thr Trp Val
22.5 9.7 15.7 27.5 21.6 7.4 16.1 16.2 4.7 19.8
45.2 11.0 14.0 25.2 19.3 6.7 21.8 14.0 3.0 19.4
5.4 2.8 4.4 9.2 4.3 2.4 5.9 3.8 1.5 5.6
50.4 10.8 16.8 30.6 11.7 5.0 24.1 11.7 4.7 20.0
Dispensable amino acids Ala Asp Cys Glu Gly Pro Tyr Ser
16.7 26.7 8.6 65.5 19.3 24.1 11.0 14.3
16.9 38.0 6.6 80.6 17.7 16.3 11.5 17.6
5.1 6.9 2.1 31.0 5.2 10.4 3.6 5.1
17.9 52.2 5.1 85.5 27.1 18.2 17.9 18.2
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The ileal digestibility and total tract metabolizability coefficients (C) of nutrients and energy were calculated as previously reported (Bolarinwa and Adeola, 2012). The product of C and GE concentration (kcal/kg) of the diet were used to calculate the IDE, ME, and MEn. The definition that the test diet energy consists of energy from reference diet and the energy from test ingredient make the sum of proportional contribution of energy of the reference diet and the test ingredient equal to 1: Prd + Pti = 1, where Prd and Pti represent proportion of energy contribution from reference diet and test ingredient, respectively. The coefficients of ME for reference diet, test diets, and test ingredients are Crd , Ctd , and Cti , respectively. The assumption of additivity in diet formulation gives: Ctd = (Crd × Prd ) + (Cti ×
Pti ); solving for Cti gives: Cti = [Ctd − (Crd × Prd )] / Pti ; substituting 1 − Pti for Prd gives: Cti = [Crd + (Ctd − Crd )/Pti ]. The GLM procedure of SAS (SAS, 1989) was used to analyze growth performance and digestibility data for the 2 experiments in a randomized complete block design as previously described (Bolarinwa and Adeola, 2012). The effects of increasing levels of CM or CSM in test diets in Exp. 1 and BM or PFM in test diets in Exp. 2 were compared using linear and quadratic contrasts. Regression of the test ingredient-associated IDE, ME, or MEn intake in kilocalories against kilograms of test ingredient intake for cage of birds was conducted using multiple linear regression for each experiment using the SAS statements described by Bolarinwa and Adeola (2012). Statistical significance was determined at an α level of 0.05.
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ENERGY VALUES OF BROILER FEED INGREDIENTS Table 4. Growth performance of birds fed experimental diets from d 21 to 28 posthatch in Exp. 1 and 2.1 P – value Item Exp. 1
Initial BW, g Final BW, g Weight gain, g Feed intake, g G:F, g:kg Exp. 2
Reference diet
125 g/kg canola meal
250 g/kg canola meal
774 1,249 475 698 679
774 1,263 489 713 684
773 1,243 470 672 698
Reference diet
200 g/kg bakery meal
400 g/kg bakery meal
814 1,348 534 768 700
812 1,325 512 768 668
812 1,309 497 772 650
L2
Q2
L3
Q3
100 g/kg cottonseed meal 774 1,312 539 748 718
200 g/kg cottonseed meal 774 1,234 460 710 650
0.5 24.2 24.3 29.0 19.4
0.337 0.882 0.894 0.540 0.486
0.577 0.576 0.582 0.434 0.845
0.747 0.681 0.671 0.768 0.298
0.710 0.023 0.023 0.216 0.033
100 g/kg peanut flour meal 814 1,320 506 765 662
200 g/kg peanut flour meal 813 1,314 501 742 677
0.7 19.4 19.6 24.6 29.1
0.977 0.489 0.161 0.918 0.222
0.983 0.933 0.900 0.963 0.852
0.985 0.547 0.218 0.474 0.576
0.994 0.815 0.608 0.763 0.451
1
Data are means of 8 replicate cages with 8 birds per cage. Linear (L) and quadratic (Q) contrasts for canola meal in Exp. 1 and bakery meal in Exp. 2, respectively. 3 Linear (L) and quadratic (Q) contrasts for cottonseed meal in Exp. 1 and peanut flour meal in Exp. 2, respectively. 2
Table 5. Ileal digestibility and total tract utilization of DM, nitrogen, and energy of birds fed experimental diets from d 21 to 28 posthatch in Exp. 1 and 2.1 P – value Item Exp. 1 Ileal digestibility DM Energy IDE, kcal/kg DM Total tract metabolizability DM coefficient Energy, N-corrected energy ME, kcal/kg DM MEn , kcal/kg DM Exp. 2 Ileal digestibility DM Energy IDE, kcal/kg DM Total tract metabolizability DM coefficient Energy, N-corrected energy ME, kcal/kg DM MEn , kcal/kg DM
SD
L2
Q2
L3
Q3
Reference diet
125 g/kg canola meal
250 g/kg canola meal
100 g/kg cottonseed meal
200 g/kg cottonseed meal
0.760 0.783 3,645
0.729 0.757 3,470
0.677 0.717 3,365
0.726 0.761 3,596
0.697 0.729 3,417
0.024 0.023 0.109
< 0.001 < 0.001 < 0.001
0.328 0.497 0.466
< 0.001 < 0.001 < 0.001
0.845 0.619 0.178
0.729 0.772 0.715 3,596 3,329
0.703 0.744 0.685 3,411 3,142
0.666 0.721 0.656 3,386 3,079
0.709 0.759 0.699 3,588 3,303
0.687 0.735 0.667 3,443 3,129
0.020 0.018 0.016 0.083 0.076
< 0.001 < 0.001 < 0.001 < 0.001 < 0.001
0.525 0.715 0.981 0.035 0.073
< 0.001 < 0.001 < 0.001 0.001 < 0.001
0.885 0.450 0.288 0.067 0.034
Reference diet
200 g/kg bakery meal
400 g/kg bakery meal
100 g/kg peanut flour meal
200 g/kg peanut flour meal
0.791 0.838 3,963
0.775 0.824 3,832
0.790 0.833 3,862
0.769 0.828 4,020
0.768 0.833 4,212
0.020 0.017 0.076
0.956 0.076 0.025
0.525 0.086 0.495
0.007 0.012 < 0.001
0.956 0.076 0.025
0.718 0.773 0.729 3,659 3,451
0.710 0.762 0.724 3,545 3,364
0.726 0.776 0.742 3,598 3,438
0.715 0.777 0.725 3,769 3,520
0.701 0.774 0.721 3,913 3,648
0.031 0.028 0.023 0.133 0.105
0.605 0.834 0.257 0.337 0.786
0.350 0.285 0.201 0.131 0.072
0.232 0.980 0.436 < 0.001 < 0.001
0.687 0.782 0.995 0.759 0.503
1 Data are means of 8 replicate cages with 8 birds per cage, but one IDE value and one ME value were missing in 100 g/kg canola meal treatment in Exp. 1. 2 Linear (L) and quadratic (Q) contrasts for canola meal in Exp. 1 and bakery meal in Exp. 2, respectively. 3 Linear (L) and quadratic (Q) contrasts for cottonseed meal in Exp. 1 and peanut flour meal in Exp. 2, respectively.
were higher in the reference diet compared with test diets. Linear effects were observed on DM digestibility in the diets containing either CM or CSM. Also, there was a linear decrease (P < 0.01) in diet energy digestibility with increasing levels of CM or CSM, and a similar pattern was observed in DM and energy me-
tabolizability. Quadratic effect was also observed in the diets containing CM. Nitrogen correction resulted in a 7% reduction in ME of reference diet, and an average of 8.5% reduction in ME of either CM diets or CSM diets. As seen with ME, there was a linear decrease in MEn of diets containing either CM or CSM.
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Initial BW, g Final BW, g Weight gain, g Feed intake, g G:F, g:kg
SEM
6
ZHANG AND ADEOLA Table 6. Regression equations relating test ingredient-associated energy intake to intake of canola meal (CM) or cottonseed meal (CSM) in Exp. 1 and bakery meal (BM) or peanut flour meal (PFM) in Exp. 2.1 Item Exp. 1 IDE ME MEn Exp. 2 IDE ME MEn
r2
SD
Y = 9 (14) + 2,132 (143) × CM + 2,197 (171) × CSM Y = –0.3 (14) + 2,286 (151) × CM + 2,568 (180) × CSM Y = 6 (14) + 1,931 (150) × CM + 2,078 (178) × CSM
0.88 0.88 0.84
48 48 48
Y = –14 (11) + 3,412 (111) × BM + 4,801 (131) × PFM Y = –7 (13) + 3,176 (125) × BM + 4,601 (148) × PFM Y = –8 (10) + 3,093 (96) × BM + 4,112 (114) × PFM
0.98 0.97 0.98
40 45 35
Regression equation
1 Values in parentheses are SE; Y is in kilocalories, intercept is in kilocalories, and the slopes are in kilocalories/kg of DM.
DISCUSSION Many alternative ingredients have been used to replace corn and SBM to meet the animals’ dietary nutrients requirements with proper formulation (Fernandez et al., 1994). An accurate determination of alternative ingredients nutrients and energy value will help to formulate a proper diet and satisfy animal requirements (Bolarinwa and Adeola, 2012). In current study, CM, CSM, BM, and PFM were chosen to determine energy value for broiler chickens. Canola meal has less digestible energy and protein, and more glucosinolates compared with SBM (Slominski and Campbell, 1991). In the current study, the inclusion of CM did not affect growth performance, which agrees with previous report that there was no significant effect of partially replacing SBM with CM on growth performance of broilers. One possible explanation is that when the inclusion level of CM was low, CM with an average of 3.9 μmol/g glucosinolates contributed only small amount of antinutrients into the diets, which would have limited effects on growth performance, considering a 4 μmol/g of diet as the max-
imum level of glucosinolates inclusion rate for broilers (Khajali and Slominski, 2012). However, in CSM diets, there was a quadratic effect on final BW, weight gain, and G:F by adding CSM, which is consistent with previous findings that incorporation of 150 g/kg CSM in broiler diets depressed BW and feed intake (El-Boushy and Raterink, 1989). This depression of BW and feed intake may be caused by several factors. First, the CSM protein is deficient in essential amino acids, such as Met, Lys, Thr, and Val (Fernandez et al., 1995). In addition, the digestibility of amino acids in CSM is also low, due to high concentration of cell-wall constituents, which leads to faster passage rate of digesta in small intestine (Sandal, 1974; Nagalakshmi et al., 2007). Another reason is due to the free gossypol in CSM. The concentration of free gossypol in CSM varies from 200 to 5,300 mg/kg (Nagalakshmi et al., 2007), and can have direct inhibitory action on certain enzymes such as pepsinogen, pepsin, and trypsin in the avian gastrointestinal tract. Also, gossypol can combine with the free epsilon amino group of Lys, and lead to peptides unavailable to the proteolytic action, hence further decreasing the digestibility of protein (Sharma et al., 1978). In the current experiment, the digestibility of DM and energy were depressed by adding CM and CSM. As a result, IDE, ME, and MEn were linearly decreased with the increasing level of CM and CSM. One of the major reasons may due to the high fiber content of CM and CSM (Bell, 1993; Nagalakshmi et al., 2007). When the inclusion of CM and CSM increased, the increased fiber diets may result in a lower protein and energy digestibility (Hetland et al., 2004). Another reason may be due to the anti-nutrients from CM and CSM, such as glucosinolates and gossypol. As described above, those anti-nutrients may also negatively affect energy digestibility. In Exp. 2, adding BM into the test diets did not affect birds growth performance, which agrees with previous findings that inclusion of bakery product in diets at levels up to 25% had no adverse effects on growth performance of broilers (Saleh et al., 1996). The same results were observed for PFM: there was no effect on growth performance of 28 d broilers by adding PFM. Formulating BM into the test diets had no effect on ME,
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In Exp. 2, the inclusion of either BM or PFM to the reference diet did not affect the growth performance of birds from d 21 to 28 posthatch (Table 4). Adding BM linearly decreased IDE, but had no effects on DM and energy metabolizability coefficients, ME, and MEn values. Adding PFM linearly reduced DM and energy digestibility, but increased IDE value. The PFM inclusion had no effects on DM metabolizability, energy metabolizability, and N-corrected energy metabolizability, but linearly increased ME and MEn (P < 0.01). Energy values are shown in Table 6. All values are reported on a DM basis. In Exp. 1, the IDE were 2,132 kcal/kg DM for CM and 2,197 kcal/kg for CSM; the ME were 2,286 kcal/kg DM for CM and 2,568 kcal/kg for CSM; MEn were 1,931 kcal/kg DM for CM and 2,078 kcal/ kg for CSM. In Exp. 2, IDE values were 3,412 kcal/kg DM for BM and 4,801 kcal/kg DM for PFM; ME values were 3,176 kcal/kg DM for BM and 4,601 kcal/kg DM for PFM; MEn values were 3,093 kcal/kg DM for BM and 4,112 kcal/kg DM for PFM.
ENERGY VALUES OF BROILER FEED INGREDIENTS
and 2,078 kcal/kg of DM, respectively. The CSM used in current study is decorticated, which has a higher ME than undecorticated CSM (Sharma et al., 1978). The decorticated CSM has ME ranging from 1,901 to 2,811 kcal/kg, mainly depending on the residual oil content (Nagalakshmi et al., 2007), and our results fall within this range. The ME in current study is more than 300 kcal/kg higher than IDE, the explanation for this is not well understood. One possible explanation is because of the comparatively high fiber contents in CSM, which resulted in the production of short-chain fatty acid in ceca, contributed partly to this energy increment (Annison et al., 1968). The same with CM, the MEn of CSM is also lower than that of SBM, which is also mainly due to the high fiber concentration and anti-nutrients. The determined IDE, ME, and MEn values of BM in current study were 3,412, 3,176, and 3,093 kcal/kg respectively. Dale et al. (1990) reported 36 bakery products with MEn ranging from 3,050 to 3,980 kcal/kg, our result fall within this range. However, NRC (1994) reported a MEn of 3,862 kcal/kg DM of BM, which is higher than the result from current study. Based on the current study, BM can provide a similar amount of energy as corn. As a result, it should be considered as an excellent alternative source of energy in poultry diets. To our knowledge, limited information about available energy of PFM has been published. The IDE, ME, and MEn values of PFM in current study were determined to be 4,801, 4,601, and 4,112 kcal/kg respectively, which is higher than most energy ingredients due to the high oil concentration present in PFM. In conclusion, the current study provided the energy values for these test ingredients and showed that they can provide a considerable amount of energy for broiler chickens. However, as with many byproducts, the nutrients contents vary widely, more data is needed to build up a robust database for broiler chickens.
REFERENCES Almeida, F., G. Petersen, and H. Stein. 2011. Digestibility of amino acids in corn, corn coproducts, and bakery meal fed to growing pigs. J. Anim. Sci. 89:4109–4115. Annison, E. F., K. J. Hill, and R. Kennworthy. 1968. Volatile fatty acids in the digestive tract of the fowl. Br. J. Nutr. 22:207–216. AOAC International. 2000. Official Methods of Analysis. 17th ed. Association of Official Analytical Chemists, Arlington, VA. Bell, J. 1993. Factors affecting the nutritional value of canola meal: a review. Can. J. Anim. Sci. 73:689–697. Bolarinwa, O., and O. Adeola. 2012. Energy value of wheat, barley, and wheat dried distillers grains with solubles for broiler chickens determined using the regression method. Poult. Sci. 91:1928– 1935. Dale, N., G. Pesti, and S. Rogers. 1990. True metabolizable energy of dried bakery product. Poult. Sci. 69:72–75. El-Boushy, A., and R. Raterink. 1989. Replacement of soybean meal by cottonseed meal and peanut meal or both in low energy diets for broilers. Poult. Sci. 68:799–804. Fenton, T. W., and M. Fenton. 1979. An improved procedure for the determination of dietary chromic oxide in feed and feces. Can. J. Anim. Sci. 59:631–634. Fernandez, S. R., S. Aoyagi, Y. Han, C. M. Parsons, and D. H. Baker. 1994. Limiting order of amino acids in corn and soybean meal for growth of the chick. Poult. Sci. 73:1887–1896.
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and MEn , but linearly decreased IDE. Because BM is produced by mixing different available byproducts, the explanation for the decreasing IDE of BM diets is not specifically known. It may be due to the high concentration of non-starch polysaccharides (NSP). There was a high variability of NSP content in bakery meal, ranging from 34 to 170 g/kg. Samples with high NSP may affect available energy (Slominski et al., 2004). In PFM diets, DM and energy digestibility were depressed as the inclusion of PFM increased, but IDE of test diet were increased as PFM increased. The results indicate that the energy digestibility coefficient for PFM derived using the regression method is 0.830, which is lower than the reference diet. Hence, a test ingredient with a lower energy digestibility coefficient will take the place of the more digestible part in reference diet, and will decrease the dietary digestibility. A possible reason for the lower energy digestibility of PFM compared with reference diet is the high phytate content in PFM (Namkung and Leeson 1999; Iyayi et al., 2013). The phytate concentration of the PFM used in current study was analyzed to be 2.78 g/kg, which accounts for 62.6% of total phosphorus. Phytate can form complexes with proteins and reduce protein digestibility, and also interfere with proteases in the gastrointestinal tract to decrease the digestibility of protein and amino acids (Singh and Krikorian, 1982). As a result, the digestibility of energy will be negatively affected. However, because of the high GE content of PFM, the GE of test diets increased as the PFM inclusion level increased, the IDE of test diets still be increased. The same for ME and MEn , metabolizable energy coefficient for PFM derived using the regression method was higher than the reference diet, the GE of test diets is higher than reference diet as well, which led to the linear increase in ME and MEn . In avian species, ME is corrected for nitrogen balance by subtracting 8.22 kcal of ME per g of nitrogen retention from the measured ME values (Hill and Anderson, 1958). In the current study, nitrogen correction resulted in a 15, 19, and 10% reduction for protein sources CM, CSM, and PFM, respectively, and a 4% reduction for BM. Obviously, there was more reduction in ME of protein ingredients than that of BM after nitrogen correction, because more nitrogen was retained in CM, CSM, and PFM groups compared with BM group. The IDE, ME, and MEn values measured in current study using regression method for CM were 2,132, 2,286, and 1,931 kcal/kg of DM, respectively. The average MEn of CM for poultry is 2,000 kcal/kg (NRC, 1994), which is close to the result in current study. The MEn of CM is 230 kcal/kg lower than that of SBM. The main reason for the lower ME of CM may be due to the high dietary fiber content, which could accelerate the digesta passage rate, and consequently reduce the time for digestion and nutrient utilization (Hetland et al., 2004). In addition, comparatively high concentration of anti-nutrients could reduce nutrients utilization and further decrease ME. The IDE, ME, and MEn values of CSM using regression method were 2,197, 2,568,
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ZHANG AND ADEOLA NRC. 1994. Nutrient Requirements of Poultry. 9th rev. ed. Natl. Acad. Press, Washington, DC. Saleh, E., S. Watkins, and P. Waldroup. 1996. High-level usage of dried bakery product in broiler diets. J. Appl. Poult. Res. 5:33–38. Sandal, D. 1974. Rapid method for evaluating metabolizable energy of poultry feeds. M. Sc. Thesis, Punjab Agricultural University, Ludhiana, India. SAS Institute. 1989. SAS/STAT User’s Guide. SAS Institute Inc., Cary, NY. Sharma, N., G. Lodhi, and J. Ichhponani. 1978. Comparative feeding value of expeller-processed undecorticated and decorticated cottonseed cakes for growing chicks. J. Agric. Sci. 91:531–541. Singh, M., and A. Krikorian. 1982. Inhibition of trypsin activity in vitro by phytate. J. Agr. Food. Chem. 30:799–800. Slominski, B. A., D. Boros, L. D. Campbell, W. Guenter, and O. Jones. 2004. Wheat by-products in poultry nutrition. Part I. Chemical and nutritive composition of wheat screenings, bakery by-products and wheat mill run. Can. J. Anim. Sci. 84:421–428. Slominski, B. A., and L. D. Campbell. 1991. Influence of indole glucosinolates on the nutritive quality of canola meal. Pages 396–401 in Proc. 8th Int. Rapeseed Congress, Saskatoon, SK, Canada. Canola Council of Canada, Winnipeg, MA, Canada.
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Fernandez, S. R., Y. Zhang, and C. M. Parsons. 1995. Dietary formulation with cottonseed meal on a total amino acid versus a digestible amino acid basis. Poult. Sci. 74:1168–1179. Hetland, H., M. Choct, and B. Svihus. 2004. Role of insoluble nonstarch polysaccharides in poultry nutrition. World’s Poult. Sci. J. 60:415–422. Heywang, B., and A. Kemmerer. 1966. Effect of gossypol source and level on chick growth. Poult. Sci. 45:1429–1430. Hill, F. W., and D. L. Anderson. 1958. Comparison of metabolizable energy and productive determinations with growing chicks. J. Nutr. 64:587–603. Iyayi, E., F. Fru-Nji, and O. Adeola. 2013. True phosphorus digestibility of black-eyed pea and peanut flour without or with phytase supplementation in broiler chickens. Poult. Sci. 92:1595– 1603. Khajali, F., and B. A. Slominski. 2012. Factors affecting the nutritive value of canola meal for poultry. Poult. Sci. 91:2564–2575. Nagalakshmi, D., S. V. R. Rao, A. K. Panda, and V. R. Sastry. 2007. Cottonseed meal in poultry diets: a review. J. Poult. Sci. 44:119–134. Namkung, H., and S. Leeson. 1999. Effect of phytase enzyme on dietary nitrogen-corrected apparent metabolizable energy and the ileal digestibility of nitrogen and amino acids in broiler chicks. Poult. Sci. 78:1317–1319.