The beneficial impacts of nano-propolis liposomes as an anti-stressor agent on broiler chickens kept under cyclic heat stress

This research assessed the impacts of dietary nano-propolis liposomes (NPRL) inclusion on the growth, blood biochemical components, immune function, and oxidative status of broilers exposed to cyclic heat stress (HS). Birds were fed with a basal diet supplemented with various levels of NPRL at 0 (HS), 100 (NPRL100), 250 (NPRL250) and 400 (NPRL400) mg/kg diets. Diets supplemented with NPRL significantly improved the growth indices and feed utilization, hemoglobin and red blood cells (P < 0.01). White blood cells, lymphocytes and monocytes were significantly decreased by NPRL inclusion (P < 0.001). Dietary supplementation of 250 or 400 mg of NPRL /kg reduced the pathogenic bacteria counts (Salmonella, E. coli and Enterococci) (P < 0.01). The birds fed diets with NPRL (400 mg/kg diet) significantly downregulated the mRNA IFNγ gene (p < 0.001), while both groups (NPRL100 and NPRL250) had similar results (P > 0.05). The iNOS gene was significantly decreased by the dietary NPRL inclusion in a dose-dependent manner. Birds in NRPL groups had inferior levels of the mRNA of interleukin-4 and tumor necrosis factor genes. The lysosome activity was significantly reduced by dietary 250 or 400 mg of NPRL inclusion (P < 0.001). Birds in NPRL250 and NPRL100 had greater IgG (P < 0.05) than the other groups. Regarding oxidative-related biomarkers, dietary NPRL inclusion decreased myeloperoxidase and malondialdehyde levels significantly compared to those with the HS group (P < 0.001). Broilers in the NPRL400 group had the lowest levels of total bilirubin and gamma-glutamyl transferase. NPRL250 had the lowest values of urea compared with other groups (P < 0.001). Dietary NPRL inclusion improved the broiler's hepatic and intestinal architecture exposed to cyclic heat stress. These results indicate that employing NPRL in the diets of stressed broilers can enhance heat resistance by enhancing blood metabolites and immunity, reducing inflammation and oxidative stress.

Dietary branched-chain amino acid assessment in broilers from 22 to 35 days of age

Background

Valine and isoleucine are similar in chemical structure and their limitation in broiler chicken diets. To evaluate their limitation and interactive effects, multivariate assessment nutrition studies for the branched-chain amino acids (BCAA) are needed. A three level (− 1, 0, + 1), three-factor Box-Behnken design study was conducted to assess dietary BCAA ratios to lysine of 65, 75, and 85 for valine, 58, 66, and 74 for isoleucine, and 110, 130, and 150 for leucine in male and female Lohman Indian River broilers from 22 to 35 d of age.

Results

Live performance of male broilers was not affected by BCAA level. However, male broilers fed increasing isoleucine had improved (P = 0.07) carcass yield as leucine and valine were reduced. Female broilers had improved body weight gain (P = 0.05) and feed conversion (P = 0.003) when leucine and isoleucine were at their lowest levels, independent of valine, but increasing leucine impaired live performance and warranted concomitant increases in isoleucine to restore responses. Increasing dietary isoleucine and valine in female broilers increased breast meat yield (P = 0.05), but increasing leucine tended to diminish the response.

Conclusion

The female Lohman Indian River broiler is more sensitive to BCAA diet manipulation than males. Specifically, as dietary leucine is increased in female broilers, dietary isoleucine increases were needed to offset the negative effects. Both increases in dietary valine and isoleucine improved breast meat yield in female broilers, but only when birds were fed the lowest dietary leucine.

Responses in growth performance and nutrient digestibility to a multi-protease supplementation in amino acid-deficient broiler diets

The present study was conducted to investigate the effect of a multi-protease on production indicators of broiler chickens fed a crude protein and amino acid deficient-diets for 35 days immediately after hatch. A total of 448 one-day-old Ross 308 male broiler chicks were allocated in a completely randomized design into one of eight dietary treatments (positive control [PC], negative control [NC: minus 0.5% from PC, and minus 2% of lysine, methionine, threonine and methionine plus cysteine], extreme negative control [ENC: minus 1% from PC, minus 4% of lysine, methionine, threonine and methionine plus cysteine], and plus multi-protease 150 or 300 g per ton [e. g., PC-150]; PC, PC-150, NC, NC-150, NC-300, ENC, ENC-150, ENC-300) to give eight replicates with seven birds in a battery cage. Body weight, average daily gain, average daily feed intake, feed conversion ratio, and mortality were measured every week. Carcass traits, proximate analysis of breast meat, and ileum digestibility were analyzed on day 21 and 35. Feeding a multi-protease (i.e., more than 150 g/ton) for 35 days immediately after hatching improved feed efficiency and ileum digestibility (i.e., dry matter, crude protein, and energy) compared to their counterparts (i.e., diets without multi-protease: PC, NC, and ENC). In conclusion, our results indicated that broiler chickens fed nutrients deficient-diet (i.e., crude protein and amino acids) supplemented a multi-protease had an ability to compensate and (or) improve their growth performance commensurate with increased ileal digestibility for 35 days immediately after hatch.

Estimation of optimal ratios of digestible phenylalanine + tyrosine, histidine, and leucine to digestible lysine for performance and breast yield in broilers

Three experiments were carried out to estimate the optimal ratios of digestible phenylalanine + tyrosine (Phe + Tyr), histidine (His), and leucine (Leu) relative to digestible lysine (Lys) for performance and carcass criteria of Cobb-500 broilers from 8 to 17 d of age. In each experiment, 160 male chicks were allocated to a completely randomized experimental design with eight replicate pens, each receiving five dietary treatments. A common, semi-purified basal diet was formulated to meet all dietary recommendations except for those of the tested amino acids (i.e., Phe + Tyr, His, and Leu). Growth performance and carcass characteristics data were analyzed using various requirement-estimation models, including 95% of the quadratic regression, linear response plateau (LRP; i.e., stepwise regression), LRP-to-quadratic regression ratio; and quadratic broken line (QBL). Graded digestible Phe + Tyr ratios elicited a quadratic response (P < 0.05) in body weight gain and linear responses (P < 0.05) in breast and breast fillet weights. Linear effects (P < 0.05) were also observed when graded ratios of digestible His were fed for feed intake and weight gain, and quadratic responses (P < 0.05) were noted for feed conversion ratio and breast and breast fillet weights and yields. Graded Leu ratios elicited quadratic responses (P < 0.05) in feed intake, weight gain, and breast and breast fillet weight and yield. Based on growth and carcass parameters, the estimated ideal digestible ratios of Phe + Tyr, His, and Leu relative to digestible Lys were 112, 38, and 104%, respectively, for broiler chicks raised from 8 to 17 d of age.

Impact of second line limiting amino acids' deficiency in broilers fed low protein diets with rapeseed meal and de-oiled rice bran

Aim:

To study the impact of deficiency of second line limiting amino acids (SLAA; valine, isoleucine and tryptophan) on the production performance and carcass characteristics of commercial broilers.

Materials and Methods:

A control (T₁) corn-soy diet was formulated to contain all essential AA on standardized ileal digestible basis; While in T₂-a ‘moderate SLAA deficit’ diet was formulated by replacement of soybean meal with 6% rapeseed meal and T₃-a ‘high SLAA deficit’ diet was formulated by replacement of soybean meal with 6% de-oiled rice bran. Each of these treatments was allotted to six replicates of ten chicks each. During the 42 days experimental period, growth performance, carcass parameters and intake of metabolizable energy (ME), crude protein (CP) and AA were studied.

Results:

The cumulative body weight gain, feed conversion ratio, carcass cut weights and yields of carcass, breast and thighs were decreased (p<0.05) in T₃ compared to T₁. The absolute intake of ME, lysine, methionine + cysteine and threonine were not affected while intake of CP and all SLAA were reduced in SLAA deficit diets. The relative intake of ME, lysine, methionine + cysteine, threonine and SLAA reduced in T₃ in comparison to T₁. The relative weights of internal organs were not affected by treatments while the abdominal fat percentage was increased linearly to the magnitude of SLAA deficiency.

Conclusion:

The deficiency of SLAA decreased performance, carcass yields and impaired utilization of ME, CP and AA linearly to the magnitude of the deficiency.

Desempenho e rendimento de carcaça em frangos de corte de um a 46 dias alimentados com dietas contendo diferentes níveis de valina e reduzido teor proteico

Este estudo teve como objetivo avaliar as relações de valina:lisina digestíveis em dietas com teor reduzido de proteína bruta (PB) e os efeitos dessa redução sobre desempenho e rendimento de carcaça em frangos de corte. Foram utilizados 1200 pintos machos seguindo modelo inteiramente ao acaso, com seis tratamentos de seis repetições (exceto controle, com 10 repetições), compostos por 30 aves cada. O tratamento controle (T1) foi formulado conforme os níveis de proteína bruta e aminoácidos (AAs) recomendados por Rostagno et al . (2011), e os demais tratamentos (T2 a T6) tiveram seus níveis de PB reduzidos (4% em relação ao controle) e variaram em função da relação valina:lisina digestíveis, com cinco níveis equidistantes em intervalos de 0,07:1, variando de 0,63:1 e 0,91:1 (dietas até 21 dias) e de 0,64:1 e 0,92:1 (dietas após 21 dias). As seguintes características de desempenho foram avaliadas: ganho de peso, consumo de ração, conversão alimentar, viabilidade criatória e índice de eficiência produtiva. Aos 46 dias de idade, seis animais por repetição foram abatidos para determinação de rendimento de carcaça e de cortes comerciais. As diferentes relações valina:lisina digestíveis não influenciaram o desempenho dos animais (P>0,05) para nenhuma característica avaliada. A redução proteica piorou a conversão alimentar dos animais (P≤0,05) até os 21 dias. Os resultados sugerem que os níveis de valina utilizados não afetam o desempenho dos animais, apenas o rendimento de peito e que, portanto, a redução proteica não é recomendada durante as três primeiras semanas de criação.

Optimisation of broiler chicken responses from 0 to 7 d of age to dietary leucine, isoleucine and valine using Taguchi and mathematical methods

Three experiments were conducted to evaluate the applicability of the Taguchi method (TM) and optimisation algorithms to optimise the branch chain amino acids (BCAA) requirements in 0 to 7 d broiler chicks. In the first experiment, the standardised digestible (SID) amino acids and apparent metabolisable energy (AME) values of maize, wheat and soya bean meal were evaluated. In the second experiment, three factors including leucine (Leu), isoleucine (Ile) and valine (Val), each at 4 levels, were selected, and an orthogonal array layout of L16 (4(3)) using TM was performed. After data collection, optimisation of average daily gain (ADG) and feed conversion ratio (FCR) were obtained using TM. The multiobjective genetic algorithm (MOGA) and random search algorithm (RSA) were also applied to predict the optimal combination of BCAA for broiler performance. In the third experiment, a growth study was conducted to evaluate the applicability of obtained optimum BCAA requirements data by TM, MOGA and RSA, and results were compared with those of birds fed with a diet formulated according to Ross 308 recommendations. In the second experiment, the TM resulted in 13.45 g/kg SID Leu, 8.5 g/kg SID Ile and 10.45 g/kg SID Val as optimum level for maximum ADG (21.57 g/bird/d) and minimum FCR (1.11 g feed/g gain) in 0- to 7-d-old broiler chickens. MOGA predicted the following combinations: SID Leu = 14.8, SID Ile = 9.1 and SID Val = 10.3 for maximum ADG (22.05) and minimum FCR (1.11). The optimisation using RSA predicted Leu = 16.0, Ile = 9.5 and Val = 10.2 for maximum ADG (22.67), and Leu = 15.5, Ile = 9.0 and Val = 10.4 to achieve minimum FCR (1.08). The validation experiment confirmed that TM, MOGA and RSA yielded optimum determination of dietary amino acid requirements and improved ADG and FCR as compared to Aviagen recommendations. However, based on the live animal validation trial, MOGA and RSA overpredicted the optimum requirement as compared to TM. In general, the results of these studies showed that the TM may be used to optimise nutrient requirements for poultry.

Bootstrapped neural network models for analyzing the responses of broiler chicks to dietary protein and branched chain amino acids

Faridi, A., Golian, A., Heravi Mousavi, A. and France, J. 2014. Bootstrapped neural network models for analyzing the responses of broiler chicks to dietary protein and branched chain amino acids. Can. J. Anim. Sci. 94: 79–85. Reliable prediction of avian responses to dietary nutrients is essential for planning, management, and optimization activities in poultry nutrition. In this study, two bootstrapped neural network (BNN) models, each containing 100 separated neural networks (SNN), were developed for predicting average daily gain (ADG) and feed efficiency (FE) of broiler chicks in response to intake of protein and branched chain amino acids (BCAA) in the starter period. Using a re-sampling method, 100 different batches of data were generated for both the ADG and FE sets. Starting with 270 data lines extracted from eight studies in the literature, SNN models were trained, tested, and validated with 136, 67, and 67 data lines, respectively. All 200 SNN models developed, along with their respective BNN ones, were subjected to optimization (to find the optimum dietary protein and BCAA levels that maximize ADG and FE). Statistical analysis indicated that based on R 2, the BNN models were more accurate in 76 and 56 cases (out of 100) compared with the SNN models developed for ADG and FE, respectively. Optimization of the BNN models showed protein, isoleucine, leucine, and valine requirements for maximum ADG were 231.80, 9.05, 14.03 and 10.90 g kg−1 of diet, respectively. Also, maximum FE was obtained when the diet contained 232.30, 9.07, 14.50, and 11.04 g kg−1 of protein, isoleucine, leucine, and valine, respectively. The results of this study suggest that in meta-analytic modelling, bootstrap re-sampling algorithms should be used to better analyze available data and thereby take full advantage of them. This issue is of importance in the animal sciences as producing reliable data is both expensive and time-consuming.

Determination of the fourth and fifth limiting amino acids in broilers fed on diets containing maize, soybean meal and poultry by-product meal from 28 to 42 d of age

1. Valine (Val) is considered the 4th limiting amino acid for broilers fed on diets containing ingredients from vegetable origin. However, Val and Isoleucine (Ile) may be co-limiting for broilers fed on diets containing animal protein meals. An experiment was conducted to examine growth responses and meat yield of broilers provided diets varying in digestible Val (dVal) and digestible Ile (dIle) concentrations from 28 to 42 d of age. 2. Eight experimental diets varying in dVal (dVal to dLys ratios from 0·66 to 0·76) and dIle (dIle to dLys ratios from 0·57 to 0·67) were studied; digestible Lysine (Lys) was formulated to 9·9 g/kg in all diets. 3. Broilers fed on a negative control (NC) diet supplemented with crystalline Val (L-Val) and crystalline Ile (L-Ile), dVal to dLys = 0·76 and dIle to dLys = 0·67, grew faster and had higher breast meat yield than birds fed on NC + L-Ile (dVal to dLys = 0·66 and dIle to dLys = 0·67), NC + L-Val (dVal to dLys = 0·76 and dIle to dLys = 0·57), and NC + reduced L-Val and L-Ile (dVal to dLys = 0·71 and dIle to dLys = 0·62). 4. Feeding broilers on the NC + L-Val and L-Ile (dVal to dLys = 0·76 and dIle to dLys = 0·67) diets gave similar BW gain, carcase weight and yield and total breast meat weight and yield to birds fed on the positive control-fed broilers with no added L-Val and L-Ile (dVal to dLys = 0·76 and dIle to dLys = 0·67). 5. These results indicate that Val and Ile are co-limiting in diets containing poultry by-product meal.

Dietary limitation of isoleucine and valine in diets based on maize, soybean meal, and meat and bone meal for broiler chickens

1. The dietary limitation of isoleucine (Ile) and valine (Val) was evaluated in broilers. Common diets were given to all broilers from 0 to 28 d of age. Experimental diets were provided from 28 to 42 d of age. 2. The experimental test diet was based primarily on maize, soybean meal, and meat and bone meal, and formulated to satisfy all nutrient recommendations with the exception of Ile and Val. 3. Diets were supplemented with L-Ile and L-Val at either 0·5 or 1·0 g kg⁻¹ of diet, alone or in combination. A diet composed only of commercially available amino acids and formulated to satisfy all nutrient requirements served as a positive control. 4. Body weight gain was depressed by the test diet, but recovered to a weight similar to birds fed on the positive control when Val was added to the test diet either alone or in combination with Ile. Feed efficiency improved when Val and Ile were simultaneously supplemented. 5. Abdominal fat yield was reduced with the combined supplementation of Val and Ile. Breast meat yield appeared to be more sensitive to Ile supplementation than to Val. 6. The results suggest that live performance may be more sensitive to Val, while breast meat yield was maximised with Ile supplementation. However, their combination is required for optimised growth and meat yield.

Effect of incremental levels of L-lysine and determination of the limiting amino acids in low crude protein corn-soybean meal diets for broilers

Research was conducted to determine the level of l-Lys that can be included in corn-soybean meal (C-SBM) diets for broilers before an amino acid (AA) beyond Met, Lys, Thr, or Gly becoming limiting and to determine the order of limiting AA in low CP C-SBM diets. All experiments were conducted with Ross 708 broilers (0 to 18 d of age) in brooder batteries. Treatments contained 7 or 8 replicates with 6 birds per replicate. In all experiments, a control C-SBM diet containing no l-Lys.HCl and a similar diet [positive control (PC) + Gly] with supplemental Gly to provide 2.32% total dietary Gly + Ser were fed. All diets were formulated to contain 1.26% total Lys. All diets with added l-Lys.HCl contained supplemental Gly to provide 2.32% total dietary Gly + Ser. In experiment 1, l-Lys.HCl was added to the diets at 0.02% increments from 0.15 to 0.27%. Compared with the PC + Gly diet, there were no negative effects (P > 0.10) of supplemental Lys on ADG, ADFI, or G:F. In experiment 2, l-Lys.HCl was added to the diets at 0.05% increments from 0.25 to 0.60%. Compared with the PC + Gly diet, ADG and G:F were decreased (P < 0.03) in broilers fed diets containing greater than 0.30% l-Lys.HCl but not (P > 0.10) in the 0.25% l-Lys.HCl diet. In experiment 3, l-Lys.HCl was added to the diets at 0.05% increments from 0.20 to 0.30%. Daily gain was decreased (P < 0.03) in broilers fed 0.30% l-Lys.HCl but not in those fed 0.20 or 0.25% l-Lys.HCl. In experiment 4, the order of limiting AA was determined in a C-SBM diet containing 0.45% L-Lys.HCl. In addition to the PC and PC + Gly diets, diets consisted of a negative control (NC) diet with 0.45% l-Lys.HCl, NC + 0.247% Ile, NC + 0.484% l-Arg.HCl, NC + 0.249% Val, and all possible 2- and l-way combinations of all 3 AA. Compared with the NC diet, addition of Arg and the combination of Arg and the other AA increased ADG and ADFI, indicating that Arg was the limiting AA in this diet. Experiment 5 was conducted in an identical manner to experiment 4 except the diets with the added AA contained the same ratio of corn to soybean meal that is present in a diet with 0.25% l-Lys.HCl. The results of experiment 5 suggest that Arg and Val are equaling limiting in a diet with 0.25% l-Lys.HCl. In summary, 0.25% l-Lys.HCl can be added to C-SBM diets supplemented with Met, Thr, and Gly with no negative effects on growth performance, and Arg and Val are equaling limiting (after Met, Thr, Lys, and Gly) in diets containing 0.25% l-Lys.HCl.