Nitrogen (N) balance studies were conducted with male growing broiler chickens to reevaluate the lysine (Lys) requirement of a modern broiler strain (Ross 308), making use of eight diets with graded crude protein (CP)...Nitrogen (N) balance studies were conducted with male growing broiler chickens to reevaluate the lysine (Lys) requirement of a modern broiler strain (Ross 308), making use of eight diets with graded crude protein (CP) supply (6% - 34% CP as-fed). Wheat, soy protein concentrate, wheat gluten, fishmeal and crystalline amino acids (AAs) were the protein sources in the experimental diets with Lys as limiting AA. Following an adaptation period of five days, two consecutive excreta collection periods (2 × 5 d) were conducted: 10 - 20 d of age (starter period) and 25 - 35 d of age (grower period). Statistical evaluation of N balance data utilized an exponential modelling approach. Based on different dietary Lys efficiency, Lys requirement data were derived by modelling depending on average body weight (BW) during starter and grower period and targeted body protein deposition (PD), respectively. In addition, the influence of graded feed intake was taken into account. For the starter period at 600 g BW and assumed 10 g daily body PD, Lys requirement data between 741 mg and 823 mg per day were observed. The corresponding Lys in-feed concentration was 1.06% and 1.18%, dependent on supposed Lys efficiency at 70 g daily feed intake. For the grower period (average BW 1800 g), 1272 mg to 1473 mg Lys per day was needed to yield 16.5 g daily PD. The corresponding required Lys in-feed concentration was between 0.85% and 0.94% Lys for 150 g daily feed intake.展开更多
The objective of this study was to measure protein quality parameters (PPV, NPU and NPUstd) of chicken diets with complete substitution of soybean meal (SBM) by Spirulina meal (SM) or partly defatted Hermetia meal (HM...The objective of this study was to measure protein quality parameters (PPV, NPU and NPUstd) of chicken diets with complete substitution of soybean meal (SBM) by Spirulina meal (SM) or partly defatted Hermetia meal (HM). N balance experiments were based on the quantitative excreta collection method, divided into starter period (10 - 20 d) and grower period (25 - 35 d). The study utilized 70 all male meat type chicken (Ross 308). Data assessment applied the exponential N utilization model of the “Goettingen approach”. The control diet was based on wheat, corn and SBM. In four experimental diets SBM was completely substituted by SM or HM, but fortified with feed amino acids (AA) both on a basic level of supplementation (Lys and Met added equal to the control diet) and on an extended level (Lys, Met, Thr, Arg, Val, Ile, His added). At a basic level of AA supplementation, complete replacement of SBM by SM or HM in chicken diets depressed dietary protein quality significantly (p 0.05). However, the extended level of AA supplementation improved protein quality parameters of the diets with both of the alternative proteins significantly (p < 0.05), but still generally not on par with the control diet. The observed responses were accentuated when the well-known effect of N intake on protein utilization was eliminated through the standardization of N intake by application of the “Goettingen approach”.展开更多
Three consecutive growth experiments were conducted to evaluate growth performance, whole body analyses and protein quality parameters from chicken diets with 50%, 75% and 100% substitution of soybean meal (SBM) by Sp...Three consecutive growth experiments were conducted to evaluate growth performance, whole body analyses and protein quality parameters from chicken diets with 50%, 75% and 100% substitution of soybean meal (SBM) by Spirulina meal (SM) or partly defatted Hermetia meal (HM). Each of the experiments was divided into a starter period (1 - 21 d) and a grower period (22 - 34 d). One-day-old male growing chickens (Ross 308) were randomly allotted to 48 floor pens making use of 6 birds/pen (Exp.1) or 7 birds/pen (Exp. 2, 3), and the experiments included a control diet (n = 12) and four experimental diets (n = 9). Experiment 1 examined a 50 % replacement of SBM by the alternative proteins under study, both on a basic and an advanced level of amino acid (AA) fortification to meet the recommended ideal amino acid ratio (IAAR). In experiment 2, 75% (starter diet) and 50% (grower diet) replacement of SBM was investigated. Experiment 3 investigated the effects of complete SBM substitution by SM or HM in starter and grower diets. In the second and third experiment diets with both of the alternative proteins and the control diet were AA supplemented to meet the current IAAR. In a further step, the calculated first limiting AA (LAA) was reduced to 80% of its requirement recommendation to allow for further evaluation of the individual AA efficiency according to the “Goettingen approach”. Different levels (50%, 75%, or 100%) of replacing SBM by HM or SM in chicken diets depressed dietary protein quality (p 0.001) and zoo-technical parameters (p 0.001) with only a basic level of AA supplementation. This effect was much more pronounced in diets with SM. However, with an extended level of dietary AA supplementation zoo-technical parameters (p 0.001), crude protein deposition (p 0.001) and protein quality parameters (p 0.001) were significantly improved. HM diets with an advanced level of AA tended to provide higher dietary protein quality and growth performance as compared to all SBM replacement levels through SM with different le展开更多
Validated procedures play an important role to obtain accurate information about individual amino acid requirement data. The aim of the present study was to assess lysine (Lys) requirement of growing chicken both by c...Validated procedures play an important role to obtain accurate information about individual amino acid requirement data. The aim of the present study was to assess lysine (Lys) requirement of growing chicken both by classical supplementation technique and principles of diet dilution technique as applied with “Goettingen approach”. During the starter period (1 - 21 d), a growth study with male meat type chicken (Ross 308) was conducted making use of five graded dietary Lys-levels (3 repetition boxes with 3 birds/box). L-Lys×HCl was gradually added to a diet based on wheat, soybean protein concentrate, wheat gluten and fishmeal to yield 80%, 87.5%, 95%, 102.5% and 110% of the expected requirement level (13 g Lys/kg as fed). Diets were iso-energetic (12.8 MJME/kg) and iso-nitrogenous (21.65% crude protein). Birds were fed on free choice level also to assess the feed intake (FI) effects as important factor on traditional response criteria. Analyzed body composition at start and end of the growth study yielded N deposition (ND) data for further data assessment using exponential approximations depending on dietary Lys content or observed Lys intake. The results indicated significant differences (p < 0.05) in response on body weight gain (BWG) and observed dietary protein quality with unexpected consequences for the derived Lys requirement data. According to the independent variable (Lys in % of diet versus daily Lys intake) and aimed level of daily ND, the needed in-feed content of Lys varied between 1.24% and 1.46%. Application of the exponential modelling by “Goettingen approach” overcame these misleading conclusions by modelling the relationship between required Lys intake and observed response data (BWG, ND) taking also into account the expected real feed intake to formulate the needed in-feed concentration.展开更多
Optimal dietary methionine (Met) to lysine (Lys) ratio in presence of elevated dietary cysteine (Cys) levels was derived for meat type growing chicken. Twelve averaged weighed Ross 308 birds (each 50% of male and fema...Optimal dietary methionine (Met) to lysine (Lys) ratio in presence of elevated dietary cysteine (Cys) levels was derived for meat type growing chicken. Twelve averaged weighed Ross 308 birds (each 50% of male and female per dietary treatment) were utilized in N balance trials. During starter (d10 - 20) and grower period (d25 - 35) five dietary treatments were used. Diets based on uniform mixtures of maize, wheat, soybean meal, potato protein and fish meal were supplemented with crystalline amino acids (AA). In diets 1 - 3, the dietary Cys to Met ratio was set as 85, 95 and 105 to 100, respectively. Diet 4, at a Cys to Met ratio of 105 to 100, was additionally supplemented with betaine (BET) as methyl group donor. Diets 1 - 4 were limiting in Met, diet 5 without L-Lys·HCl addition was limiting in Lys. Individual N-balance data per treatment were utilized for assessing protein quality and efficiency of dietary Met (Diets 1 - 4) or Lys (Diet 5) based on “Goettingen approach”. Elevated dietary Cys supply and supplemented BET failed to improve both dietary protein quality and Met efficiency. The established optimal Met to Lys ratio was on average 34 to 100 for growing chicken during starter and grower period, respectively.展开更多
文摘Nitrogen (N) balance studies were conducted with male growing broiler chickens to reevaluate the lysine (Lys) requirement of a modern broiler strain (Ross 308), making use of eight diets with graded crude protein (CP) supply (6% - 34% CP as-fed). Wheat, soy protein concentrate, wheat gluten, fishmeal and crystalline amino acids (AAs) were the protein sources in the experimental diets with Lys as limiting AA. Following an adaptation period of five days, two consecutive excreta collection periods (2 × 5 d) were conducted: 10 - 20 d of age (starter period) and 25 - 35 d of age (grower period). Statistical evaluation of N balance data utilized an exponential modelling approach. Based on different dietary Lys efficiency, Lys requirement data were derived by modelling depending on average body weight (BW) during starter and grower period and targeted body protein deposition (PD), respectively. In addition, the influence of graded feed intake was taken into account. For the starter period at 600 g BW and assumed 10 g daily body PD, Lys requirement data between 741 mg and 823 mg per day were observed. The corresponding Lys in-feed concentration was 1.06% and 1.18%, dependent on supposed Lys efficiency at 70 g daily feed intake. For the grower period (average BW 1800 g), 1272 mg to 1473 mg Lys per day was needed to yield 16.5 g daily PD. The corresponding required Lys in-feed concentration was between 0.85% and 0.94% Lys for 150 g daily feed intake.
文摘The objective of this study was to measure protein quality parameters (PPV, NPU and NPUstd) of chicken diets with complete substitution of soybean meal (SBM) by Spirulina meal (SM) or partly defatted Hermetia meal (HM). N balance experiments were based on the quantitative excreta collection method, divided into starter period (10 - 20 d) and grower period (25 - 35 d). The study utilized 70 all male meat type chicken (Ross 308). Data assessment applied the exponential N utilization model of the “Goettingen approach”. The control diet was based on wheat, corn and SBM. In four experimental diets SBM was completely substituted by SM or HM, but fortified with feed amino acids (AA) both on a basic level of supplementation (Lys and Met added equal to the control diet) and on an extended level (Lys, Met, Thr, Arg, Val, Ile, His added). At a basic level of AA supplementation, complete replacement of SBM by SM or HM in chicken diets depressed dietary protein quality significantly (p 0.05). However, the extended level of AA supplementation improved protein quality parameters of the diets with both of the alternative proteins significantly (p < 0.05), but still generally not on par with the control diet. The observed responses were accentuated when the well-known effect of N intake on protein utilization was eliminated through the standardization of N intake by application of the “Goettingen approach”.
文摘Three consecutive growth experiments were conducted to evaluate growth performance, whole body analyses and protein quality parameters from chicken diets with 50%, 75% and 100% substitution of soybean meal (SBM) by Spirulina meal (SM) or partly defatted Hermetia meal (HM). Each of the experiments was divided into a starter period (1 - 21 d) and a grower period (22 - 34 d). One-day-old male growing chickens (Ross 308) were randomly allotted to 48 floor pens making use of 6 birds/pen (Exp.1) or 7 birds/pen (Exp. 2, 3), and the experiments included a control diet (n = 12) and four experimental diets (n = 9). Experiment 1 examined a 50 % replacement of SBM by the alternative proteins under study, both on a basic and an advanced level of amino acid (AA) fortification to meet the recommended ideal amino acid ratio (IAAR). In experiment 2, 75% (starter diet) and 50% (grower diet) replacement of SBM was investigated. Experiment 3 investigated the effects of complete SBM substitution by SM or HM in starter and grower diets. In the second and third experiment diets with both of the alternative proteins and the control diet were AA supplemented to meet the current IAAR. In a further step, the calculated first limiting AA (LAA) was reduced to 80% of its requirement recommendation to allow for further evaluation of the individual AA efficiency according to the “Goettingen approach”. Different levels (50%, 75%, or 100%) of replacing SBM by HM or SM in chicken diets depressed dietary protein quality (p 0.001) and zoo-technical parameters (p 0.001) with only a basic level of AA supplementation. This effect was much more pronounced in diets with SM. However, with an extended level of dietary AA supplementation zoo-technical parameters (p 0.001), crude protein deposition (p 0.001) and protein quality parameters (p 0.001) were significantly improved. HM diets with an advanced level of AA tended to provide higher dietary protein quality and growth performance as compared to all SBM replacement levels through SM with different le
文摘Validated procedures play an important role to obtain accurate information about individual amino acid requirement data. The aim of the present study was to assess lysine (Lys) requirement of growing chicken both by classical supplementation technique and principles of diet dilution technique as applied with “Goettingen approach”. During the starter period (1 - 21 d), a growth study with male meat type chicken (Ross 308) was conducted making use of five graded dietary Lys-levels (3 repetition boxes with 3 birds/box). L-Lys×HCl was gradually added to a diet based on wheat, soybean protein concentrate, wheat gluten and fishmeal to yield 80%, 87.5%, 95%, 102.5% and 110% of the expected requirement level (13 g Lys/kg as fed). Diets were iso-energetic (12.8 MJME/kg) and iso-nitrogenous (21.65% crude protein). Birds were fed on free choice level also to assess the feed intake (FI) effects as important factor on traditional response criteria. Analyzed body composition at start and end of the growth study yielded N deposition (ND) data for further data assessment using exponential approximations depending on dietary Lys content or observed Lys intake. The results indicated significant differences (p < 0.05) in response on body weight gain (BWG) and observed dietary protein quality with unexpected consequences for the derived Lys requirement data. According to the independent variable (Lys in % of diet versus daily Lys intake) and aimed level of daily ND, the needed in-feed content of Lys varied between 1.24% and 1.46%. Application of the exponential modelling by “Goettingen approach” overcame these misleading conclusions by modelling the relationship between required Lys intake and observed response data (BWG, ND) taking also into account the expected real feed intake to formulate the needed in-feed concentration.
文摘Optimal dietary methionine (Met) to lysine (Lys) ratio in presence of elevated dietary cysteine (Cys) levels was derived for meat type growing chicken. Twelve averaged weighed Ross 308 birds (each 50% of male and female per dietary treatment) were utilized in N balance trials. During starter (d10 - 20) and grower period (d25 - 35) five dietary treatments were used. Diets based on uniform mixtures of maize, wheat, soybean meal, potato protein and fish meal were supplemented with crystalline amino acids (AA). In diets 1 - 3, the dietary Cys to Met ratio was set as 85, 95 and 105 to 100, respectively. Diet 4, at a Cys to Met ratio of 105 to 100, was additionally supplemented with betaine (BET) as methyl group donor. Diets 1 - 4 were limiting in Met, diet 5 without L-Lys·HCl addition was limiting in Lys. Individual N-balance data per treatment were utilized for assessing protein quality and efficiency of dietary Met (Diets 1 - 4) or Lys (Diet 5) based on “Goettingen approach”. Elevated dietary Cys supply and supplemented BET failed to improve both dietary protein quality and Met efficiency. The established optimal Met to Lys ratio was on average 34 to 100 for growing chicken during starter and grower period, respectively.
