Browsing by Author "Wester TJ"

Now showing 1 - 8 of 8
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    Barley, an Undervalued Cereal for Poultry Diets: Limitations and Opportunities
    (MDPI (Basel, Switzerland), 2022-10-01) Perera WNU; Abdollahi MR; Zaefarian F; Wester TJ; Ravindran V
    The supply of conventional cereal grains, especially of maize, will be a significant constraint to the future growth of the poultry industry. Various alternative feed ingredients are being tested to replace maize in poultry diets. Barley (Hordeum vulgare L.) is one such feed ingredient, the use of which remains limited in poultry diets due to its low metabolisable energy, presence of anti-nutritive, soluble non-starch polysaccharides and consequent inter-cultivar variability. Differences in research methodologies used in published studies have also contributed to the inconsistent findings, preventing a good understanding of the nutritional value of barley for poultry. The importance of using accurate nutrient profiles, specifically metabolisable energy and digestible amino acids, for specific barley cultivars to formulate barley-based diets is emphasised. Nutritionists should also pay close attention to feed processing conditions tailored to the specific barley cultivars to increase the barley inclusion in poultry diets.
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    Basal ileal endogenous amino acid flow in broiler chickens as influenced by age
    (Elsevier Inc, 2021-08) Barua M; Abdollahi MR; Zaefarian F; Wester TJ; Girish CK; Chrystal PV; Ravindran V
    The current study was carried out to measure the basal ileal endogenous amino acid (EAA) flow in male broilers (Ross 308) at different ages (d 7, 14, 21, 28, 35, and 42), following the feeding of a nitrogen-free diet. Titanium dioxide (5 g/kg) was included as an indigestible marker. The nitrogen-free diet was offered for four days prior to ileal digesta collection to 6 replicate cages housing 14 (d 3–7), 12 (d 10–14), 10 (d 17–21), 8 (d 24–28), 8 (d 31–35), and 6 (d 38–42) birds per cage. The basal EAA flow was calculated as g/kg DM intake. The amino acid (AA) profile of endogenous protein, expressed as g/100 g protein, was also calculated. The basal endogenous flow of nitrogen and all individual and total AA decreased quadratically (P < 0.05 to 0.001), with flows being higher on d 7, then decreasing on d 14, plateauing until d 35 and decreasing further on d 42. The concentrations of Trp, Cys, and Gly in the endogenous protein increased linearly (P < 0.01 to 0.001) with advancing age, whereas a linear decrease (P < 0.001) was noted for Lys. A quadratic influence (P < 0.05 to 0.001) was observed for the concentrations of Ile, Leu, Met, Val, and Asp. These changes in the endogenous protein profile may be attributed to variations in the contribution of endogenous sources with age but delineating the exact contribution of different sources is complicated. Overall, the current findings suggest that the basal ileal EAA flow is influenced by broiler age and age-specific EAA flows may need to be considered to standardize the AA digestibility.
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    Evaluation of equations for predicting ileal nutrient digestibility and digestible nutrient content of broiler diets based on their gross chemical composition
    (Elsevier B V, 2024-06) Thiruchchenthuran S; Lopez-Villalobos N; Zaefarian F; Abdollahi MR; Wester TJ; Pedersen NB; Storm AC; Cowieson AJ; Morel PCH
    The coefficient of apparent ileal digestibility (CAID) and ileal digestible contents (IDC) of nutrients of 56 diets using 10 feed ingredients were measured in broilers (21–24 d post-hatch). Diets contained varying inclusion levels of traditional and non-traditional ingredients and differed widely in chemical composition. The chemical composition and in vivo digestibility values were used to establish prediction equations for CAID and IDC of nutrients using stepwise multiple regression. The strength and accuracy of the developed equations were evaluated by root mean square error (RMSE), coefficient of determination (R2), adjusted R2 (adj. R2), and Akaikie's Information Criteria (AIC). The bootstrap method was used to validate the choice of variables by stepwise selection method in the original equation based on their frequencies of selection. Selection of variables was validated if the variables that appear in the original stepwise model were selected in more than 30% of the 1000 bootstrap samples. A close agreement between the original equations and bootstrap resampling was observed for CAID of nitrogen (N) and energy and IDC of energy, starch, and calcium (Ca). Additionally, the original data was subjected to another run of stepwise regression analysis using the selected variables by bootstrapping. The initial regression showed that the CAID of N and energy was highly dependent on crude fibre (CF) and energy contents of the diets. The CAID of energy can be predicted (R2 = 0.89 and RMSE = 0.035) by CF, gross energy (GE), CF2, and starch-to-CF ratio (starch:CF). Calcium content had a positive influence, while phosphorus (P) content had a negative influence on the prediction of CAID of fat. The main variable to predict CAID and IDC of most nutrients was the dietary CF content. Based on the lowest RMSE and AIC, the best predictors for IDC of N were ash, N, fat, CF, CF2, and starch:CF, while the best predictors for IDC of energy were CF, GE, CF2, and starch:CF. The results of the original stepwise regression models and the stepwise regression with the selected variables from the bootstrap results for CAID of N, energy, fat, and DM, as well as IDC of energy, starch, and Ca, were the same with no differences in R2, Adj. R2, RMSE, and AIC. This method can be useful for developing stable and reproducible models using stepwise regression. However, an external validation is needed to confirm the use of these equations in commercial settings.
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    High steam-conditioning temperature during the pelleting process impairs growth performance and nutrient utilization in broiler starters fed barley-based diets, regardless of carbohydrase supplementation
    (Elsevier Inc. on behalf of Poultry Science Association Inc., 2021-08) Perera WNU; Abdollahi MR; Zaefarian F; Wester TJ; Ravindran V
    The influence of supplemental carbohydrase (Carb) and conditioning temperature (CT) on growth performance, nutrient utilization and intestinal morphometry of broilers (d 1–21) fed barley-based diets was examined in a 2 × 3 factorial arrangement, evaluating 2 levels of Carb (0 and 150 g/tonne of feed) and three CT (60, 74, and 88°C). A total of 288, 1-day-old male broilers (8 birds/cage; 6 cages/treatment) were used. The activities of endo-1,4-β- glucanase, endo-1,3 (4)-β-glucanase and endo-1,4-β-xylanase in the Carb were 800 BGU/g, 700 BGU/g and 2,700 XU/g, respectively. On d 21, ileal digesta was collected for the determination of nutrient digestibility. There was no significant interaction between Carb and CT for any tested parameter. Supplemental Carb, regardless of CT, increased weight gain (WG; P < 0.05) and reduced feed per gain (F/G; P < 0.001) by 30 g/bird and 6.5 points, respectively. Increasing CT to 88°C reduced (P < 0.05) WG, but increased (P < 0.05) F/G compared to the diets conditioned at 60° and 74°C. Regardless of CT, Carb enhanced (P < 0.05) the digestibility of starch and AMEn by 1.15% and 32 kcal/kg, respectively. Compared to the diets conditioned at 60° and 74°C, CT at 88°C reduced (P < 0.05) digestibility of dry matter, nitrogen, phosphorus, gross energy, and AMEn. Birds fed diets conditioned at 88°C showed lower (P < 0.05) starch digestibility compared to those fed diets conditioned at 60°C. Conditioning at 88°C increased (P < 0.05) jejunal digesta viscosity by 10.2% compared to diets conditioned at 60° and 74°C. Overall, Carb supplementation improved WG, F/G, starch digestibility and AMEn in broilers fed barley-based diets, irrespective of CT applied. Conditioning barley-based diets at 88°C impaired the ability of birds to utilize nitrogen, starch, phosphorus and energy, and consequently deteriorated WG and F/G. The lack of significant interactions between Carb and CT indicated that negative impacts caused by high CT on bird performance and nutrient utilization occurred regardless of Carb enzyme supplementation. Supplemental Carb per se could not remedy the adverse effects of high CT.
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    Influence of Age on the Standardized Ileal Amino Acid Digestibility of Corn and Barley in Broilers
    (MDPI (Basel, Switzerland), 2021-12) Barua M; Abdollahi MR; Zaefarian F; Wester TJ; Girish CK; Chrystal PV; Ravindran V
    The aim of this study was to determine the standardized ileal digestibility coefficients (SIDCs) of nitrogen (N) and amino acids (AAs) in corn and barley at six different ages (days 7, 14, 21, 28, 35 and 42) of broilers using the direct method. The apparent AA digestibility coefficients were corrected using age-appropriate basal endogenous AA losses. No age effect (p > 0.05) was noted for the SIDC of N in corn. The average SIDC of indispensable AAs (IAAs) and total AAs (TAAs) was influenced in a quadratic manner (p < 0.05) with the values being higher at day 7 that decreased at day 14, increased and plateaued between days 21 and 35 and dropped again at day 42. The average SIDC of dispensable AAs (DAAs) was influenced linearly (p < 0.05). In barley, the SIDC of N and average IAAs, DAAs and TAAs was affected (quadratic; p < 0.001) by age. The digestibility increased from day 7 to 21 and then plateaued up to day 42. The present findings confirm that the SIDC of AA in corn and barley are influenced by broiler age and that the age effect on AA digestibility may need to be considered for precise feed formulation.
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    Influence of different levels of black soldier fly larvae meal on growth performance and carcass quality of broiler chickens
    (Elsevier B.V., 2024-11-02) Baderuddin SH; David LS; Wester TJ; Morel PCH
    A study was conducted to examine the impact of two inclusion levels of Black soldier fly larvae meal (BSFLM) replacing soybean meal on growth performance, nutrient utilization, carcass characteristics and meat quality of broilers. Three experimental diets based on corn-soybean meal were developed to contain 0 (control), 6 (BSF 6) and 12% (BSF 12) BSFLMfor both starter and grower phases. Each experimental diet was randomly allotted to six replicate pens (eight birds per pen). The birds were offered starter pellets from 0 to 14 day post-hatch and grower pellets from 15 to 28 day post-hatch. The experimental diets were tested for pellet durability index (PDI). There was an interaction between diet and growth phase (P < 0.001) for pellet durability index where starter diets had always a higher PDI than the grower diets, but the difference was greater for control diet than BSF 6 and BSF 12 diets. Apparent metabolizable energy (AME) of diets and coefficients of apparent ileal digestibility (CAID) of nutrients were measured on day 28 using titanium dioxide marker ratios in the diet and excreta/ileal digesta. On day 28, the weights of live body, carcass, fat pad, breast and gizzard were recorded, and then breast meat quality (meat pH, drip loss and cooking loss) was examined. Inclusion of BSFLM of up to 12 % did not reduce live weight gain or feed intake. Live weight and carcass weight were heavier in broilers fed 12 % BSFLM than controls (P < 0.02), but were not different than those fed 6 %, while controls were not different than those fed 6 %. Breast weight (percentage live weight) was lower in birds offered 12 % BSFL than in others (P < 0.04). No differences were observed between diets for the percentage weight as carcass, fat, pad and gizzard. The AME and AMEc of diets were the highest in broilers fed 6 % BSFLM diet (P < 0.005), but there were no differences between controls and those fed 12 % BSFLM. The CAID of DM, ash and N in birds fed 6 % BSFLM were greater than (P < 0.03) birds fed 12 %, but were not different than controls, which were also not different than those fed 12 %. Broiler breast meat quality was unaffected by dietary treatments. In conclusion, BSFLM at 12 % can be used effectively as a SBM replacement in starter and grower diets, without affecting the growth performance, nutrient utilization, carcass characteristics and meat quality of broiler chickens.
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    Provision of lucerne in the diet or as a manipulable enrichment material enhances feed efficiency and welfare status for growing-finishing pigs
    (1/10/2022) Nguyen TT; Chidgey KL; Wester TJ; Morel PCH
    This research investigated the effects of including lucerne in a diet and as manipulable enrichment material on growing-finishing pig growth performance and behaviour. Forty-eight intact male Duroc × (Large White × Landrace) pigs with an initial live weight (LW) of 26.4 ± 2.32 kg (mean ± SD) were blocked by LW and randomly assigned to two dietary treatments (control vs lucerne), and two manipulable material treatments (without and with lucerne chaff for manipulable material). The barley and soybean meal-based control diet was formulated according to a commercial standard, while the lucerne diet replaced 100 g/kg of the barley and soybean oil in the control diet with lucerne chaff. The diets were formulated to have the same amount of digestible energy and apparent ileal digestible lysine. Manipulable material (lucerne chaff) was provided daily at 100 g/pig. Pigs had ad libitum access to diets via electronic feeders until they reached approximately 90 kg LW, at which time they were slaughtered. There were no interactions between dietary treatment and provision of manipulable material on pig production and behaviour. Feeding the lucerne diet reduced average daily feed intake, LW gain, feed intake per feeder visit, and feeding rate, but increased feed efficiency (P < 0.05). Access to manipulable material did not affect any growth traits, but the number of feeder visits per day was greater and the duration of visits to the feeder was lower in pigs that had access to lucerne chaff (P < 0.001). Compared to the other groups, pigs that consumed the lucerne diet or had access to manipulable material rested for a shorter duration but engaged in more social interactions and exploration behaviour. In conclusion, including 10% lucerne in growing-finishing diets improved feed efficiency and lucerne chaff appears to be an attractive enrichment source to pigs.
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    Using poultry by-product meal to replace soybean meal in grower -finisher pig diets
    (Elsevier B V, 2024-07-01) Nguyen TT; Chidgey KL; Wester TJ; Schreurs NM; Morel PCH
    This study investigated the effect of replacing soybean meal (SBM) with poultry by-product meal (PBM) in grower-finisher diets on pig feeding, growth performance, carcass yield and meat quality. The replacement levels were increased from no PBM (PBM0) to 37 g/kg PBM (PBM37), 85 g/kg PBM (PM85) and 111 g/kg PBM (PBM111). All diets met or exceeded nutrient requirements for pigs between 20 – 100 kg live weight (NRC, 2012). Sixty-four entire males (PIC 337 x PIC Camborough 42), at an average live weight (LW) of 27.60 ± 2.48 kg (mean ±SD) were blocked by LW and randomly assigned to 8 pens, with each diet replicated across 2 pens. Pigs had ad libitum access to diets via electronic feeders until they reached approximately 100 kg LW, at which time they were slaughtered. Results showed no significant effect of replacing SBM with PBM on pig feeding behavior parameters and the majority of pig growth performance, carcass yield, and meat quality traits, with the exception of higher feed conversion ratio (FCR) in pigs fed the PBM37 diet. Loin muscles from the group fed the PBM111 diet had significantly lower ultimate pH and a greater cooking loss than the other treatments (P < 0.05). Loin muscles from pigs fed high levels of PBM (PBM85 and PBM111) had greater ash content than those fed the PBM37 and control diets (P = 0.001). Overall, the present research indicated that PBM could be a viable primary protein source in diets for growing-finishing pigs, as it did not appear to have any adverse effects on pig feeding behavior, growth performance and meat quality. In addition, PBM is potentially a good source of calcium and phosphorus for growing–finishing pigs. However, due to the variation in quality and composition of available PBM, it is essential to measure nutritional composition before including PBM in diets for growing-finishing pigs.