Effects of Crude Protein and Amino Acid to Lysine Ratio on Finishing Pig Growth Performance and Carcass Characteristics

The increased availability of synthetic amino acids has reduced the amount of intact protein sources used in swine diets. The objective of this study was to determine the effects of different CP levels and AA to Lys ratios on growth performance and carcass characteristics in late finishing pigs. A total of 1,682 pigs (327 × 1050, PIC, Hendersonville, TN; initially 252.7 lb BW) were used in a 25-d growth trial arranged in an unbalanced randomized complete block design with 25 pigs per pen and initially 8 or 16 pens per treatment. Dietary treatments were arranged in a 2 × 2 + 1 factorial consisting of combinations of 10.3 or 13.5% CP and 2 AA to Lys ratios plus a control diet (13.5% CP from soybean meal). The standardized ileal digestible (SID) ratios to Lys were 55% Met+Cys, 68% Thr, 17% Trp, 65% Val, 56% Ile, and 32% His for PIC (2013) and 60% Met+Cys, 68% Thr, 20% Trp, 72% Val, 55% Ile, and 37% His for the Modified ratio.Overall, from d 0 to 25, pigs fed the control diet had increased ADG (P \u3c 0.001) compared with pigs fed diets formulated with the PIC or Modified AA:Lys ratios. There were no statistical differences in ADFI observed between the treatments. For F/G, there was a 2-way marginally significant interaction (P = 0.066) where F/G was improved for pigs fed the PIC AA:Lys ratios with 13.5% CP compared to those fed diets with 10.3% CP; however, there were no statistical differences in F/G between CP levels in pigs fed Modified AA:Lys ratios. Final BW was increased in pigs fed the control compared to pigs fed diets formulated with the PIC (P = 0.017) or Modified (P \u3c 0.001) AA:Lys ratios. Pigs fed 10.5% CP provided by glutamic acid and glycine, regardless of AA:Lys ratio, had increased (P = 0.031) carcass yield; however, there was no statistical differences between the dietary treatments regarding HCW, backfat, loin depth, and percentage lean.In conclusion, reducing intact protein (soybean meal) decreased growth performance and the inclusion of a nitrogen source (glycine and glutamic acid) was not able to recover growth performance in this commercial study. The 2 amino acid ratios in the low crude protein diets evaluated in this study did not improve growth performance or carcass characteristics

The effect of local thermal fluctuations on the folding kinetics: a study from the perspective of the nonextensive statistical mechanics

Protein folding is a universal process, very fast and accurate, which works consistently (as it should be) in a wide range of physiological conditions. The present work is based on three premises, namely: ($i$) folding reaction is a process with two consecutive and independent stages, namely the search mechanism and the overall productive stabilization; ($ii$) the folding kinetics results from a mechanism as fast as can be; and ($iii$) at nanoscale dimensions, local thermal fluctuations may have important role on the folding kinetics. Here the first stage of folding process (search mechanism) is focused exclusively. The effects and consequences of local thermal fluctuations on the configurational kinetics, treated here in the context of non extensive statistical mechanics, is analyzed in detail through the dependence of the characteristic time of folding ($\tau$) on the temperature $T$ and on the nonextensive parameter $q$.The model used consists of effective residues forming a chain of 27 beads, which occupy different sites of a $3-$D infinite lattice, representing a single protein chain in solution. The configurational evolution, treated by Monte Carlo simulation, is driven mainly by the change in free energy of transfer between consecutive configurations. ...Comment: 19 pages, 3 figures, 1 tabl

Effects of AminoGut and Diet Formulation Approach on Growth Performance and Economic Return in Nursery Pigs

Diets containing animal protein sources have higher levels of glutamine than diets based on plant protein sources. Therefore, the objective of this study was to determine the effects of AminoGut (Ajinomoto Heartland, Inc., Chicago, IL) and protein source (animal vs. plant proteins) on growth performance and economic return in nursery pigs from 12 to 60 lb. AminoGut is a product that contains both glutamine and glutamate. A total of 1,134 pigs (337 × 1050; PIC, Hendersonville, TN, initially 11.6 ± 0.18 lb BW) were used in a 52-d trial. At the beginning of the experiment, pigs were weighed in pens, and pens were ranked by average BW and randomly assigned dietary treatments in a randomized complete block design based on BW. The treatment structure was a 2 × 3 factorial with 2 protein sources (animal vs. plant) and 3 AminoGut durations (0, 10, and 24 d). The experiment was divided into Phases 1 (d 0 to 10), 2 (d 10 to 24), and 3 (d 24 to 52). Pigs were fed a common diet during Phase 3. AminoGut was added at 0.8 and 0.6% in Phases 1 and 2, respectively. From d 0 to 10, pigs fed animal protein-based diet had marginally (P = 0.074) greater ADG and improved F/G (P = 0.035) compared to pigs fed plant-based diet. No evidence for differences was observed in pigs fed AminoGut in this phase (P \u3e 0.188). From d 10 to 24, pigs fed AminoGut had improved ADG (linear, P \u3c 0.022) and F/G (linear, P = 0.004). No evidence for differences was observed between protein sources in this phase. From d 24 to 52, pigs that had been previously fed AminoGut for 10 d had marginally improved F/G (quadratic, P = 0.057) compared to pigs not previously fed AminoGut or previously fed AminoGut for 24 d. No evidence for differences was observed between protein sources in this common phase. For the combined performance from Phases 1 and 2 (d 0 to 24), pigs fed AminoGut had improved ADG (linear, P \u3c 0.021), F/G (linear, P = 0.004), and BW (quadratic, P = 0.028) compared to pigs not fed AminoGut. No evidence for differences was observed between pigs fed different protein sources. For the overall performance (d 0 to 52), no statistical evidence for differences between pigs fed protein source or different AminoGut duration was observed. In conclusion, feeding AminoGut for 10 d post-weaning marginally improved growth performance until d 24 but there was no carry over effect when a common diet was fed from d 24 to 52. Further research should evaluate the supplementation of glutamine and glutamate throughout the nursery period and at greater inclusion levels

Current fluctuations in stochastic systems with long-range memory

We propose a method to calculate the large deviations of current fluctuations in a class of stochastic particle systems with history-dependent rates. Long-range temporal correlations are seen to alter the speed of the large deviation function in analogy with long-range spatial correlations in equilibrium systems. We give some illuminating examples and discuss the applicability of the Gallavotti-Cohen fluctuation theorem.Comment: 10 pages, 1 figure. v2: Minor alterations. v3: Very minor alterations for consistency with published version appearing at http://stacks.iop.org/1751-8121/42/34200

Effects of Dietary Standardized Ileal Digestible Valine:Lysine Ratio on 14 to 22 lb Nursery Pigs

A total of 280 nursery pigs (PIC 327 × 1050; initially 14.4 lb BW) were used in a 28-d growth trial to evaluate the effects of increasing dietary standardized ileal digestible (SID) Valine:Lysine (Val:Lys) ratio on nursery pig growth performance. Pigs were weaned at approximately 21 d of age and allotted to pens according to BW and gender. A common starter diet was fed for 5 d, and then pens were allotted to 1 of 7 dietary treatments in a randomized complete block design according to BW. Experimental diets were fed for 14 d, which included SID valine concentrations of 50, 57, 63, 68, 73, 78, and 85% of Lys. Then pigs were fed a common Phase 3 diet for 14 d.From d 0 to 14, when experimental diets were fed, ADG, ADFI, and F/G improved (quadratic, P \u3c 0.036) as SID Val:Lys ratio increased. For ADG, the best-fitting model was the broken line linear (BLL). This model resulted in a maximum ADG to be achieved when feeding a minimum of 62.9% SID Val:Lys ratio. For ADFI, the quadratic polynomial (QP) was the best fitting model, predicting maximum feed intake at 73.7% SID Val:Lys ratio and 99% of maximum performance achieved with 68.0% SID Val:Lys ratio. For feed efficiency, modeled as G:F, the best-fitting model was the QP, estimating maximum G:F at 71.7% SID Val:Lys ratio. In conclusion, this experiment demonstrated that the SID valine requirement for 14 to 22 lb nursery pigs ranged from 62.9 to 73.7% of Lys depending on the response criteria modeled

Lysine requirement titration for barrows and gilts from 25-to 75-kg

Citation: Landero, J. L., Young, M. G., Touchette, K. J., Stevenson, M. J., Clark, A. B., Goncalves, M. A. D., & Dritz, S. S. (2016). Lysine requirement titration for barrows and gilts from 25-to 75-kg. Journal of Animal Science, 94, 95-95. doi:10.2527/msasas2016-201Lysine is the first limiting amino acid in practical swine diets, so it is important to optimize the dietary digestible lysine to maximize growth and profitability. Two experiments were conducted to estimate the standardized ileal digestible (SID) Lys requirement for pigs from 25- to 50-kg BW (Exp. 1) and 50- to 75-kg BW (Exp. 2) using ADG and G:F as criteria responses. A total of 1050 barrows and gilts (FAST F1 female × PIC380 boar line) were used in each experiment, blocked by gender, with 10 pens per treatment and 21 pigs per pen. Experimental diets were formulated to contain 2.3 Mcal NE/kg and to meet or exceed all nutrient requirements except Lys, according to NRC (2012). Minimum ratios of 30% Met:Lys, 60% Met + Cys:Lys, 21% Trp:Lys, 70% Val:Lys, 55% Ile:Lys, and 102% Leu:Lys on a SID basis were used for all diets. The SID Thr:Lys ratio was 65 and 66% for Exp. 1 and 2, respectively. In Exp. 1, pigs were fed diets formulated to contain 0.72, 0.80, 0.88, 0.96 or 1.04% SID Lys whereas in Exp. 2 diets were formulated to contain 0.68, 0.75, 0.82, 0.89 or 0.96% SID Lys. Responses measured at the pen level were analyzed using general linear and nonlinear heteroskedastic mixed models. Dose response curves were evaluated using linear (LM), quadratic polynomial (QP), broken-line linear (BLL), and broken-line quadratic (BLQ) models. For each response variable, the best-fitting model was selected using Bayesian information criterion. Gender was used as covariate when significant. Increasing SID Lys content in the diet quadratically (P 1.04% SID Lys. From 50- to 75- kg BW, the best-fitting model for ADG was the BLQ estimating the requirement at 0.83% (95% confidence interval [CI]: [0.80%, 0.86%]) SID Lys, with 99% of maximum achieved with 0.82%. For G:F, the BLL was the best-fitting model and the SID Lys requirement estimated at 0.85% (95% CI: [0.75%, 0.94%]) with 99% of maximum achieved with 0.80%. In conclusion, the SID Lys requirement for 25- to 75-kg pigs may be higher than the recommendation from NRC (2012)

Effects of Dietary Standardized Ileal Digestible Isoleucine:Lysine Ratio on Nursery Pig Performance

A total of 560 nursery pigs were used in 2 experiments to evaluate the effects of increasing dietary standardized ileal digestible (SID) Isoleucine:Lysine (Ile:Lys) ratio on growth performance. In Exp. 1, 280 pigs (PIC 327 × 1050, initially 14.9 lb BW) were fed experimental diets for 12 d with 8 replications and 5 pigs per pen. In Exp. 2, 280 pigs (DNA Genetics Line 600 × Line 241, initially 13.3 lb BW) were fed experimental diets for 18 d with 8 replications and 5 pigs per pen. In both experiments, pens were allotted to 1 of 7 dietary treatments in a randomized complete block design. The 7 dietary treatments were 40, 44, 48, 52, 54, 58, and 63% SID Ile:Lys ratio. After the experimental diet feeding period, a common diet was fed for 14 d. Diets in both phases were fed in meal form.For Exp. 1, from d 0 to 12 when experimental diets were fed, ADG and ADFI improved (ADG, linear, P \u3c 0.001; and ADFI, quadratic, P \u3c 0.017) and F/G became poorer (quadratic, P \u3c 0.041) as SID Ile:Lys ratio increased. For ADG, the quadratic (QP), broken-line linear (BLL), and broken-line quadratic (BLQ) models reported maximum ADG at 64.7, 52.0, and 52.0% SID Ile:Lys ratio, respectively. For ADFI, the BLL breakpoint occurred at 50.6% and the QP predicted maximum ADFI at 56.2% SID Ile:Lys ratio.In Exp. 2, from d 0 to 18 when experimental diets were fed, ADG and ADFI improved (quadratic, P \u3c 0.009) with no significant differences for F/G as SID Ile:Lys ratio increased. For ADG, the BLL and QP had similar fit with breakpoints/maximums occurring at 51.8% SID Ile:Lys ratio and 58.3% SID Ile:Lys ratio, respectively. For ADFI, the QP reported maximum ADFI at 57.2% SID Ile:Lys ratio and the BLQ breakpoint occurred at 52.0% SID Ile:Lys.In summary, these experiments demonstrate that the SID Ile requirement for 15 to 25 lb nursery pigs is approximately 52% of Lys for ADG and ADFI using broken line models and can be as high as 64% of Lys using quadratic models. A slight quadratic effect was observed in feed efficiency for Exp. 1, however in Exp. 2, there were no appreciable differences detected in F/G. The Ile requirement for 15 to 25 lb pigs was found to be similar to NRC (2012) requirement estimates

Effects of Increasing Dietary Standardized Ileal Digestible Lysine on 15 to 24 lb Nursery Pigs

A total of 300 nursery pigs (PIC 327 × 1050, initially 14.8 lb BW) were used in a 28-d growth trial to evaluate the effects of increasing dietary standardized ileal digestible (SID) lysine (Lys) on nursery pig growth performance. Pigs were weaned at approximately 21 d of age and allotted to the pens according to BW and gender. A common starter diet was fed for 6 d, then pens were allotted to 1 of 6 dietary treatments in a completely randomized design. Experimental diets were fed for 14 d followed by a common diet for 14 d. The 6 dietary treatments were formulated to contain 1.10, 1.20, 1.30, 1.40, 1.50, and 1.60% SID Lys.Increasing SID Lys resulted in improved (linear, P \u3c 0.001) ADG and F/G during d 0 to 14 when experimental diets where fed, with no differences observed in ADFI. For ADG, broken line linear (BLL) and quadratic polynomial (QP) models demonstrated similar fits, with maximum ADG at 1.45% and above 1.60% for BLL and QP models, respectively. Similar estimates were found when modeling feed efficiency.In conclusion, this experiment determined that the SID Lys requirement for 15 to 24 lb nursery pigs was at least 1.45% SID Lys for both ADG and feed efficiency

Modeling the Effects of Standardized Ileal Digestible Tryptophan:Lysine Ratio on Growth Performance of 65- to 275-lb Pigs

The objective of this study was to model the effects of standardized ileal digestible (SID) Trp:Lys ratio on growth performance of 65- to 275-lb pigs. The present experiment, along with three previous experiments from Gonçalves et al. (2014), were used in the analysis. For all studies, dietary treatments consisted of SID Trp:Lys ratios of 14.5, 16.5, 18.0, 19.5, 21.0, 22.5, and 24.5%. The experiments were 21 d in duration and used corn and soybean meal-based diets with 30% dried distillers grains with solubles formulated to be deficient in Lys at the end of each of the experiments. In the current experiment, a total of 975 gilts (337 × 1050; PIC, Hendersonville, TN) were used with initial BW of 234.1 ± 6.8 lb and final BW of 274.9 ± 10.4 (mean ± SD). Pens of pigs were blocked by weight and assigned to one of the seven dietary treatments in a randomized complete block design. There were 6 pens/treatment with 20 to 24 pigs per pen. For 235 to 275 lb-pigs, increasing SID Trp:Lys improved ADG (quadratic, P \u3c 0.022), ADFI (linear, P \u3c 0.001), and F/G (linear, P \u3c 0.001). Data from all experiments were then combined for analysis using linear and non-linear mixed models with random effects of experiment and weight block nested within experiment allowing for heterogeneous variances. Competing models included broken-line linear (BLL), broken-line quadratic (BLQ), and quadratic polynomial (QP). In the combined analysis for ADG, QP was the best fitting model and estimated SID Trp:Lys requirement at 23.5% (95% CI: [22.7, 24.3%]). In the combined analysis for F/G, BLL and BLQ had comparable fit and estimated SID Trp:Lys requirements at 16.9% (95% CI: [16.0, 17.8%]) and 17.0% (95% CI: [15.0, 18.9%]), respectively. Thus, the estimated mean requirements for SID Trp:Lys for 65- to 275-lb pigs ranged from 16.9% for optimum mean F/G to 23.5% for maximum mean ADG. Furthermore, 95% of the maximum estimated mean ADG was obtained by feeding 17.6% SID Trp:Lys and 98% of the maximum estimated mean ADG was obtained by feeding 19.8% SID Trp:Lys

Nonconcave entropies in multifractals and the thermodynamic formalism

We discuss a subtlety involved in the calculation of multifractal spectra when these are expressed as Legendre-Fenchel transforms of functions analogous to free energy functions. We show that the Legendre-Fenchel transform of a free energy function yields the correct multifractal spectrum only when the latter is wholly concave. If the spectrum has no definite concavity, then the transform yields the concave envelope of the spectrum rather than the spectrum itself. Some mathematical and physical examples are given to illustrate this result, which lies at the root of the nonequivalence of the microcanonical and canonical ensembles. On a more positive note, we also show that the impossibility of expressing nonconcave multifractal spectra through Legendre-Fenchel transforms of free energies can be circumvented with the help of a generalized free energy function, which relates to a recently introduced generalized canonical ensemble. Analogies with the calculation of rate functions in large deviation theory are finally discussed.Comment: 9 pages, revtex4, 3 figures. Changes in v2: sections added on applications plus many new references; contains an addendum not contained in published versio