scholarly journals Efficiency of utilizing standardized ileal digestible lysine and threonine for whole-body protein retention in pregnant gilts during early, mid-, and late gestation1

2019 ◽  
Vol 97 (7) ◽  
pp. 3016-3026 ◽  
Author(s):  
Ronald A S Navales ◽  
Jim Dunn ◽  
John K Htoo ◽  
Kevin Touchette ◽  
Robert C Thaler ◽  
...  

Abstract Two experiments were conducted to determine the efficiency of utilizing SID Lys and Thr for whole-body protein retention (kSIDLys and kSIDThr) in pregnant gilts. In Exp. 1, 45 gilts (158.0 ± 8.0 kg at day 39.4 ± 1 of gestation) in 2 groups were used in a 3-period nitrogen (N)-balance study. Gilts were assigned to 1 of 4 diets set to provide 60, 70, 80, and 90% of predicted daily SID Lys requirement for protein retention (NRC, 2012) in each of early (day 41 to 52, 10.44 g/d), mid- (day 68 to 79, 9.60 g/d), and late gestation (day 96 to 107, 16.04 g/d). Diets contained 3,300 kcal ME/kg and 11.6% CP; given at a rate of 2.13 kg/d in early and mid-gestation and at 2.53 kg/d during late gestation. The 12-d balance period (7-d adaptation; 5-d urine and fecal collection) was based on total urine collection using urinary catheters and determination of fecal N digestibility using indigestible marker. The SID Lys required for whole-body protein retention was estimated using the NRC (2012) model and the predicted Lys content of each gestation pool. Lysine efficiency at each diet Lys level was calculated as the ratio of daily Lys retention and SID Lys intake. The linear and quadratic response in whole-body N and Lys retention and Lys efficiency for each balance period was determined. The kSIDLys was determined from the slope generated by regressing whole-body Lys retention vs. SID Lys intake, with y-intercept set to 0. In Exp. 2, 45 gilts (165.7 ± 13.6 kg at day 39.1 ± 2 of gestation) were assigned to 1 of 4 diets set to provide 60, 70, 80, and 90% of the predicted daily SID Thr requirement for protein retention in each of early (6.46 g/d), mid- (6.05 g/d), and late gestation (9.75 g/d). Animal management, N-balance procedure, data collection and calculation, and statistical analyses were patterned from Exp. 1. In early and mid-gestation, whole-body N retention, as well as Lys and Thr retention, was not affected by the dietary SID Lys and Thr. In late gestation, there was a linear increase (P < 0.001) in whole-body N, Lys and Thr retention. The kSIDLys and kSIDThr in late gestation were determined to be 0.54. The lack of response in whole-body protein retention in early and mid-gestation may in partly reflect excess Lys and Thr intake. Lysine and Thr efficiency calculated at the lowest dietary Lys and Thr was 0.49 and 0.32 in early gestation and 0.61 and 0.52 in mid-gestation, respectively. Based on the available evidence, kSIDLys and kSIDThr do not appear to be constant throughout gestation.

2018 ◽  
Vol 96 (suppl_3) ◽  
pp. 303-303
Author(s):  
R Navales ◽  
J Dunn ◽  
J Htoo ◽  
K Touchette ◽  
R Thaler ◽  
...  

2019 ◽  
Vol 97 (Supplement_2) ◽  
pp. 104-105
Author(s):  
Christian D Ramirez-Camba ◽  
James L Dunn ◽  
John K Htoo ◽  
Kevin J Touchette ◽  
Ryan S Samuel ◽  
...  

Abstract NRC (2012) gestating sow model assumes the efficiency of AA use is constant across gestation, which may not reflect changes in metabolic demand during gestation. Efficiency of utilization is determined as the slope of the response to graded levels of test AA. Previous work reported a lack of response to graded Lys [60–90% of NRC (2012) predicted requirement] in early and mid gestation. Therefore, a study was conducted to determine efficiency of SID Lys utilization for whole body protein retention in gilts and sows during early (d 48–52) and mid (d 75–79) gestation. Four isocaloric (3,373 kcal ME/kg) and isoproteic (12.75 % CP) diets containing 40, 50, 60, and 70% of NRC (2012) model-predicted daily SID Lys requirement (10.1 and 9.3 g/d in early and mid gestation, respectively) were randomly assigned to 50 females (PIC 1050; 12 gilts, 21 Parity 1, 17 Parity 2). Dietary indispensable AA contents were set to meet 100–200% of AA:Lys ratios. Whole body nitrogen (N) retention was based on N-balance studies in early and mid gestation (7-d diet adaptation and 5 d total urine collection and grab fecal sampling). Lysine efficiency was determined by simple linear regression using PROC GLM procedure of SAS. Reproductive performance data were analyzed using PROC MIXED procedure of SAS. Reproductive performance of sows (birth weight, born alive, stillborn, and mummies) was not different by parity or diet. Whole body N and SID Lys retention increased linearly (P < 0.0001) with increasing SID Lys intake in early and mid gestation. Efficiency of Lys utilization in early gestation was 0.60, 0.46, and 0.50, and in mid gestation 0.58, 0.44, and 0.48 for gilts, parity 1, and parity 2 sows, respectively. Parity may play a greater role in efficiency of AA use than stage of gestation.


Author(s):  
Paul J. Rozance ◽  
Stephanie R Wesolowski ◽  
Sonnet S. Jonker ◽  
Laura D Brown

Fetal skeletal muscle growth requires myoblast proliferation, differentiation, and fusion into myofibers in addition to protein accretion for fiber hypertrophy. Oxygen is an important regulator of this process. Therefore, we hypothesized that fetal anemic hypoxemia would inhibit skeletal muscle growth. Studies were performed in late gestation fetal sheep that were bled to anemic, and therefore hypoxemic, conditions beginning at ~125 days of gestation (term = 148 days) for 9 ± 0 days (n=19) and compared to control fetuses (n=16). A metabolic study was performed on gestational day ~134 to measure fetal protein kinetic rates. Myoblast proliferation and myofiber area were determined in biceps femoris (BF), tibialis anterior (TA), and flexor digitorum superficialis (FDS) muscles. mRNA expression of muscle regulatory factors was determined in BF. Fetal arterial hematocrit and oxygen content were 28% and 52% lower, respectively, in anemic fetuses. Fetal weight and whole-body protein synthesis, breakdown, and accretion rates were not different between groups. Hindlimb length, however, was 7% shorter in anemic fetuses. TA and FDS muscles weighed less and FDS myofiber area was smaller in anemic fetuses compared to controls. The percentage of Pax7+ myoblasts that expressed Ki67 was lower in BF and tended to be lower in FDS from anemic fetuses indicating reduced myoblast proliferation. There was less MYOD and MYF6 mRNA expression in anemic vs. control BF consistent with reduced myoblast differentiation. These results indicate that fetal anemic hypoxemia reduced muscle growth. We speculate that fetal muscle growth may be improved by strategies that increase oxygen availability.


2006 ◽  
Vol 31 (5) ◽  
pp. 557-564 ◽  
Author(s):  
Joseph W. Hartman ◽  
Daniel R. Moore ◽  
Stuart M. Phillips

It is thought that resistance exercise results in an increased need for dietary protein; however, data also exists to support the opposite conclusion. The purpose of this study was to determine the impact of resistance exercise training on protein metabolism in novices with the hypothesis that resistance training would reduce protein turnover and improve whole-body protein retention. Healthy males (n = 8, 22 ± 1 y, BMI = 25.3 ± 1.8 kg·m–2) participated in a progressive whole-body split routine resistance-training program 5d/week for 12 weeks. Before (PRE) and after (POST) the training, oral [15N]-glycine ingestion was used to assess nitrogen flux (Q), protein synthesis (PS), protein breakdown (PB), and net protein balance (NPB = PS – PB). Macronutrient intake was controlled over a 5d period PRE and POST, while estimates of protein turnover and urinary nitrogen balance (Nbal = Nin – urine Nout) were conducted. Bench press and leg press increased 40% and 50%, respectively (p < 0.01). Fat- and bone-free mass (i.e., lean muscle mass) increased from PRE to POST (2.5 ± 0.8 kg, p < 0.05). Significant PRE to POST decreases (p <0.05) occurred in Q (0.9 ± 0.1 vs. 0.6 ± 0.1 g N·kg–1·d–1), PS (4.6 ± 0.7 vs. 2.9 ± 0.3 g·kg–1·d–1), and PB (4.3 ± 0.7 vs. 2.4 ± 0.2 g·kg–1·d–1). Significant training-induced increases in both NPB (PRE = 0.22 ± 0.13 g·kg–1·d–1; POST = 0.54 ± 0.08 g·kg–1·d–1) and urinary nitrogen balance (PRE = 2.8 ± 1.7 g N·d–1; POST = 6.5 ± 0.9 g N·d–1) were observed. A program of resistance training that induced significant muscle hypertrophy resulted in reductions of both whole-body PS and PB, but an improved NPB, which favoured the accretion of skeletal muscle protein. Urinary nitrogen balance increased after training. The reduction in PS and PB and a higher NPB in combination with an increased nitrogen balance after training suggest that dietary requirements for protein in novice resistance-trained athletes are not higher, but lower, after resistance training.


2009 ◽  
Vol 49 (11) ◽  
pp. 1023
Author(s):  
L. P. Kahn ◽  
Somu B. N. Rao ◽  
J. V. Nolan

An incomplete factorial experiment was conducted to determine the effect of level and frequency of feeding of a protein-rich supplement on the growth and whole-body protein metabolism of young sheep fed a medium quality roughage diet. Cottonseed meal (CSM) was used as the protein supplement and provided at 0, 0.2 or 0.4% liveweight per day at a frequency of 1 or 3 times each week and chopped oaten (0.95) and lucerne (0.05) hay was the roughage. Growth rate more than doubled (P < 0.01) following provision of CSM but there was no advantage of feeding CSM at the highest level. Frequency of feeding CSM did not alter growth rate. Intake of hay was little affected by CSM and as a consequence the food conversion ratio declined (P < 0.01) favourably from 22 : 1 (nil CSM) to 9 : 1 as a result of supplementation. The rate of whole-body protein synthesis increased (P < 0.01) in response to the highest level of CSM with no apparent change in protein degradation, underpinning an increase (P < 0.01) in protein retention. These results highlight the role of protein supplements for promoting growth of young sheep on roughage diets and indicate that these supplements need to be provided only once a week.


2005 ◽  
Vol 80 (3) ◽  
pp. 345-351 ◽  
Author(s):  
C. Z. Roux

AbstractIn pigs the quantification of breakdown and synthesis by powers of body protein led to the estimation of turn-over related protein retention efficiency by the equation kP= {1 + [1 − (P/α)(2/9)Q]−1/6}−1, with α the limit value of whole body protein (P) maturity, so that 0 ≤(P/α)≤1. The factor 2/9 is derived from diffusion attributes indicated by cell and nucleus geometries α and Q represents a scaled transformation of intake, 0 ≤ Q ≤ 1, such that a value of Q = 1 may represent ad libitum intake and Q = 0 the intake at the maintenance requirement. Published observations on finishing steers provide estimates of whole body protein synthesis and breakdown at pre-determined levels of intake in confirmation of the theoretical (2/9)Q power associated with (P/α) inkP. Further confirmation of the (2/9)Q power in cattle follows from satisfactory agreement between an estimate of conventional multiple regression retention efficiency and the turn-over related retention efficiency calculated at the given level of intake, for the mid point of the body mass interval covered by the regression estimate. In addition, a simulation experiment on cattle from the literature gives power estimates of protein breakdown and synthesis in general agreement with those accepted for pigs. Examples on both fine and coarse diets are employed to suggest a general rule for prediction on diets causing submaximal efficiency due to suboptimal intakes.In sheep, evidence derived from estimates of conventional multiple regression efficiencies suggests that the rule (a-b) = (2/9) Q for the calculation ofkPshould be reserved for the description of compensatory growth. Protein retention efficiency for ordinary growth should be described by an adaptation of the rule derived for suboptimal intakes.


PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2368 ◽  
Author(s):  
Changsu Kong ◽  
Jong Young Ahn ◽  
Beob G. Kim

This experiment was conducted to determine the bioavailability ofD-methionine (Met) relative toL-Met for nursery pigs using the slope-ratio assay. A total of 50 crossbred barrows with an initial BW of 13.5 kg (SD = 1.0) were used in an N balance study. A Met-deficient basal diet (BD) was formulated to contain an adequate amount of all amino acids (AA) for 10–20 kg pigs except for Met. The two reference diets were prepared by supplementing the BD with 0.4 or 0.8 gL-Met/kg at the expense of corn starch, and an equivalent concentration ofD-Met was added to the BD for the two test diets. The pigs were adapted to the experimental diets for 5 d and then total but separated collection of feces and urine was conducted for 4 d according to the marker-to-marker procedure. Nitrogen intakes were similar across the treatments. Fecal N output was not affected by Met supplementation regardless of source and consequently apparent N digestibility did not change. Conversely, there was a negative linear response (P< 0.01) to Met supplementation with both Met isomers in urinary N output, which resulted in increased retained N (g/4 d) and N retention (% of intake). No quadratic response was observed in any of the N balance criteria. The estimated bioavailability ofD-Met relative toL-Met from urinary N output (g/4 d) and N retention (% of intake) as dependent variables using supplemental Met intake (g/4 d) as an independent variable were 87.6% and 89.6%, respectively; however, approximately 95% of the fiducial limits for the relative bioavailability estimates included 100%. In conclusion, with an absence of statistical significance, the present study indicated that the mean relative bioequivalence ofD- toL-Met was 87.6% based on urinary N output or 89.6% based on N retention.


2020 ◽  
Vol 98 (11) ◽  
Author(s):  
Christian D Ramirez-Camba ◽  
James L Dunn ◽  
John K Htoo ◽  
Jolie C González-Vega ◽  
Kevin Touchette ◽  
...  

Abstract The efficiency of SID Lys utilization (kSID Lys) in gilts and sows during early (days 48 to 52), mid (days 75 to 79), and late gestation (days 103 to 107) was investigated using 88 pregnant females (PIC 1050; 27 gilts, 27 parity 1 sows, 34 parity 2+ sows; 192.96 ± 22.84 kg at days 42 ±1 of gestation) and whole body nitrogen (N) retention balance studies. Females were assigned to 1 of 4 SID Lys levels ranging from 40% to 70% of the daily SID Lys requirements above maintenance for a parity 1 sow according to the NRC (2012) gestating sow model in each gestation period. Experimental diets were isocaloric (3,335 kcal ME/kg) and isoproteic (11.75 % CP) and dietary indispensable AA were set to meet or exceed 100% of AA:Lys ratios. The slope of the linear response to graded SID Lys intake was defined as kSID Lys. With the aim of increasing the accuracy of kSID Lys estimates, gilt data from the current study was combined with gilt data from a previous study conducted at the same facility using 4 SID Lys levels ranging from 60% to 90% of the daily SID Lys requirements above maintenance for gilts according to the NRC (2012) gestating sow model. Whole body Lys retention of the combined gilt data set was assessed with different broken-line and nonlinear models. The kSID Lys was 0.65, 0.38, and 0.52 for early-, mid-, and late-gestation, respectively, in gilts. A linear response to graded SID Lys intake was found in late gestation only in parity 1 and 2+ sows; kSID Lys was determined as 0.44 and 0.52 in late gestation for parity 1 and parity 2+ sows, respectively. There were no differences in kSID Lys in late gestation between parities. For the combined gilt data, the model of best performance (reduced error and greater goodness of fit) was the Hoerl model. Maximum kSID Lys (i.e., g SID Lys retention/g SID Lys intake) in gilts was 0.67, 0.54, and 0.53 in early, mid, and late gestation predicted at 7.2, 9.1, and 13.5 g of SID Lys intake/d, respectively, based on the Hoerl model. Maximum SID Lys retention in gilts was similarly predicted at 8.5, 10.5, and 20.9 g of SID Lys intake per day in early, mid, and late gestation and resultant kSID Lys of 0.61, 0.51, and 0.44, respectively. The findings of this study demonstrate that kSID Lys varies by stage of gestation and SID Lys intake level and that, at least in gilts, a dynamic kSID adjusted for daily intake more adequately reflects biological response and hence allows more precise feeding of pregnant females.


2020 ◽  
Vol 98 (Supplement_3) ◽  
pp. 73-74
Author(s):  
Christian D Ramirez-Camba ◽  
Ron Navales ◽  
James Dunn ◽  
John K Htoo ◽  
Caroline Gonzalez-Vega ◽  
...  

Abstract Efficiency of amino acid (AA) use is presumed constant across gestation but may not reflect changes in metabolic demand during gestation nor consider changes in efficiency depending on level of AA intake. Two experiments were conducted to determine efficiency of SID Lys utilization in gilts during early (d 48-52), mid (d 75-79) and late gestation (d 103-107). Each experiment provided 4 isocaloric (3,335 kcal ME/kg) and isoproteic (11.75 % CP) diets containing 4 SID Lys levels (Table 1). Diets were randomly assigned to 45 gilts (PIC 1050, 158.0 ± 8.0 kg at d 39.4 ± 1 of gestation) in Exp. 1 and 27 gilts (PIC 1050, 169.0 ± 7.5 kg at d 41 ± 1 of gestation) in Exp. 2. Dietary indispensable AA were set to meet or exceed 100% of AA:Lys ratios in both experiments. The SID Lys retention was estimated from whole body nitrogen (N) retention balance studies in each period (7 d diet adaptation, 5 d total urine collection and grab fecal sampling) according to the NRC (2012) equations. The relationship between SID Lys intake and SID Lys retention was determined by nonlinear regression models using the CurveExpert Professional software. According to the Hoerl regression model: E(y)=exp(β 0+β 1X)[Xβ2] best-fitting line, maximum efficiency of SID Lys utilization (i.e. g SID Lys retention/g SID Lys intake) was 65%, 57%, and 53% in early, mid and late gestation and occurred at 6.6, 8 and 12 g of SID Lys intake/d, respectively. Maximum SID Lys retention occurred at 8.1 and 9.8 g of SID Lys intake/d for early and mid-gestation. The SID Lys retention did not reach a maximum value in late gestation. These results suggest that efficiency of SID Lys utilization is not constant across gestation and that maximal efficiency occurs at intake below current recommendations.


Sign in / Sign up

Export Citation Format

Share Document