Journal Articles

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Author: search.filters.author.Wester TJSubject: search.filters.subject.Broiler

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    Determination of chemical composition and metabolizable energy of chickpea, faba bean, field pea, lentil and lupin compared to soybean meal for broiler chickens
    (Elsevier Inc on behalf of the Poultry Science Association Inc, 2026-02-01) Hamungalu O; Abdollahi MR; Morel PCH; Liu S; Wester TJ
    The chemical composition, apparent metabolizable energy (AME) and nitrogen-corrected apparent metabolizable energy (AMEn) of lupin, faba bean, field pea, lentil, chickpea and soybean meal were determined for growing broilers. Grain legumes were incorporated into experimental diets either raw or after being steam-conditioned at 80°C for 30 seconds. Assay diets were developed by replacing (w/w) 300 g/kg of formulated basal diet (maize-soybean meal) with one of the legumes (raw or heat-treated) or soybean meal (test sample). Each assay diet was randomly allocated to 4 replicates (8 birds per cage) and fed in mash form for 7 d (d 14 – 21 post-hatch). Feed intake and total excreta were measured in the last 4 days of the trial. Among the grain legumes, starch content was lowest in lupin (4.3 g/kg) and highest in field pea (425 g/kg). Apart from lupin, grain legumes were greater in starch than soybean meal. Crude fat of soybean meal (13.5 g/kg) was lower than that of faba bean (14.1 g/kg), field pea (18.6 g/kg), lupin (47.2 g/kg) and chickpea (58.3 g/kg), but greater than lentil (10.9 g/kg). The gross energy of grain legumes ranged from 4,275 Kcal/kg (field pea) to 4,681 kcal/kg (lupin), and that of soybean meal was 4,514 Kcal/kg. Heating of grain legumes had no effect on AME and AMEn, except for lupin, where it increased by 23.9 and 23.5 %, respectively. The AME values among the raw legumes, were highest in lentil (2,438 Kcal/kg) and lowest in lupin (1,595 Kcal/kg), with the intermediate values for chickpea (2,206 Kcal/kg), faba bean (1,923 Kcal/kg) and pea (1,970 Kcal/kg). The AME of raw legumes were lower (P < 0.05) than that of soybean meal (2,673 Kcal/kg), but N-corrected AME of lentil was not different to that of soybean meal. The current results showed that steam conditioning at 80°C was not effective to improve energy availability of grain legumes, except for lupin. Soybean meal is superior to grain legumes in terms of energy availability for broiler feeding.
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    Validation of prediction equations to estimate the nutritive value of broiler chicken diets based on their chemical composition
    (Elsevier BV, Netherlands, 2025-02-18) Thiruchchenthuran S; Zaefarian F; Abdollahi MR; Wester TJ; Morel PCH
    An experiment was conducted to validate the accuracy of previously published prediction equations developed to estimate the coefficient of apparent ileal digestibility (CAID) and ileal digestible content (IDC) of nitrogen (N), crude fat, starch, calcium (Ca), phosphorus (P), energy, and dry matter (DM) in broilers using the chemical composition of diets. Twenty new diets were formulated to have a wide range of chemical characteristics relevant to commercial diets. The CAID of N, crude fat, starch, Ca, P, energy, and DM of the diets were determined in broiler growers fed ad libitum from 15 to 22 days post-hatch. The chemical composition and in vivo digestibility values were used to validate the prediction equations developed from a previous study. Comparison between the determined values and predicted values was used to assess the accuracy of prediction equations using the coefficient of determination (R2), root mean square error of prediction, concordance correlation coefficient (CCC), and mean bias (MB). The most accurate prediction was achieved in terms of R2 and CCC for CAID of energy and DM (R2 = 0.57 and 0.66, CCC = 0.45 and 0.47, respectively) as well as for IDC of N, starch, energy, and DM (R2 = 0.90, 1.00, 0.65, and 0.66, CCC = 0.48, 0.97, 0.51, and 0.47, respectively). The R2 and CCC values obtained for CAID of N, crude fat, starch, Ca, and P and IDC of Ca and P were not consistent with the expectation of predictive performance. The R2 for IDC of crude fat was high (0.94), however, CCC was moderate (0.43). The determined MB values showed that some equations underpredicted (CAID and IDC of N, crude fat, starch, energy, and DM) and some overpredicted (CAID of Ca and P and IDC of P) the observed values of in vivo study. In conclusion, the equations obtained for CAID of energy and DM as well as IDC of N, starch, energy, and DM could be considered the best fit according to R2 and CCC. Moreover, this study highlights the importance of validation with external data before applying each prediction equation to practical situations.
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    Effect of age on the standardized ileal amino acid digestibility of soybean meal and canola meal in broilers
    (Elsevier B.V. on behalf of KeAi Communications Co., Ltd., 2023-12-02) Barua M; Abdollahi MR; Zaefarian F; Wester TJ; Girish CK; Chrystal PV; Ravindran V
    Standardized ileal digestibility coefficients (SIDC) of nitrogen (N) and amino acids (AA) in two protein sources (soybean meal [SBM] and canola meal [CM]) were investigated at six broiler ages (d 7, 14, 21, 28, 35, and 42). Two assay diets were formulated to contain either SBM (413 g/kg) or CM (553 g/kg) as the sole dietary AA source. Titanium dioxide (5 g/kg) was added as an indigestible marker. A total of 696 male broilers at 1 d old were allotted to 12 replicate cages per age group. Each assay diet was offered to birds for 4 d prior to the ileal digesta collection on d 7 (14 birds/cage), 14 (12 birds/cage), 21 (10 birds/cage), 28 (8 birds/cage), 35 (8 birds/cage) and 42 (6 birds/cage), respectively. The apparent digestibility coefficients were standardized using age-specific basal endogenous AA flows. In the SBM group, though the SIDC of N tended to be influenced (quadratic; P = 0.075) by age, no linear or quadratic response of age effect was observed on the average SIDC of indispensable (IAA) and total AA (TAA). An age effect (quadratic; P < 0.05) was observed on the average SIDC of dispensable AA (DAA) in SBM with the highest value recorded at d 7, followed by a decrease from d 14 to 28, which increased beyond d 35. The SIDC of some individual AA (Arg, Thr, Trp, Cys, Pro) were affected (P < 0.05 or P < 0.001) in a quadratic manner by age. In the CM, the SIDC of N, average SIDC of IAA, DAA and TAA were influenced (quadratic; P < 0.05 or P < 0.001) by age. The SIDC of N and average SIDC of DAA and TAA were higher from d 7 to 14, declined at d 21, and then increased beyond d 28. The average SIDC of IAA was low between d 7 and 28 and increased thereafter. The SIDC of individual AA were affected (linear or quadratic; P < 0.05 or P < 0.001) by different magnitudes by age. The age influence on the SIDC AA was variable, depending on the protein source and AA. The results demonstrate that age-specific SIDC AA data might need consideration in broiler feed formulations.