Spatial Characterization of Soybean Yield and Quality (Amino Acids, Oil, and Protein) for United States.

Continued economic relevancy of soybean is a function of seed quality. The objectives of this study were to: (i) assess the spatial association between soybean yield and quality across major US soybean producing regions, (ii) investigate the relationship between protein, oil, and yield with amino acids (AAs) composition, and (iii) study interrelationship among essential AAs in soybean seed. Data from soybean testing programs conducted across 14 US states from 2012 to 2016 period (n = 35,101 data points) were analyzed. Results indicate that for each Mg ha-1 yield increase, protein yield increased by 0.35 Mg protein ha-1 and oil yield improved by 0.20 Mg oil ha-1. Essential AA concentrations exhibit a spatial autocorrelation and there was a negative relationship between concentration of AA, protein, and oil, with latitude. There was a positive interrelationship with different degree of strength among all AAs, and the correlation between Isoleucine and Valine was the strongest (r = 0.93) followed by the correlation among Arginine, Leucine, Lysine, and Threonine (0.71 < r < 0.88). We concluded that the variability in genotype (G) x management (M) x environment (E) across latitudes influencing yield also affected soybean quality; AA, protein, and oil content in a similar manner.

Effects of high inclusion of soybean meal and a phytase superdose on growth performance of weaned pigs housed under the rigors of commercial conditions.

Two studies were conducted to determine whether soybean meal (SBM) use in nursery pig diets can be increased by superdosing with phytase. In Exp. 1, 2,550 pigs (BW of 5.54 ± 0.09 kg) were used to evaluate the optimal level of phytase in low- or high-SBM diets. Two SBM levels (low and high) and 4 phytase doses (0, 1,250, 2,500, and 3,750 phytase units [FTU]/kg) were combined to create 8 dietary treatments in a 2 × 4 factorial arrangement. Pigs were fed a 3-phase feeding program, with each period being 10, 10, and 22 d, respectively. Inclusion of low and high SBM was 15.0 and 25.0%, respectively, for Phase 1; 19.0 and 29.0%, respectively, for Phase 2; and 32.5% for the common Phase 3 diet. Pigs fed diets with high SBM had improved G:F for Phase 1 and 2 and overall ( < 0.01) compared with low-SBM diets. Phytase quadratically improved G:F during Phase 3 and overall ( < 0.05), with the optimum phytase dose being 2,500 FTU/kg. High-SBM diets tended ( = 0.09) to decrease stool firmness (determined daily from d 1 to 10) only on d 2. In Exp. 2, 2,112 pigs (BW of 5.99 ± 0.10 kg) were used to evaluate the impact of high levels of SBM and phytase on performance, stool firmness, mortality, and morbidity in weaned pigs originating from a porcine reproductive and respiratory syndrome (PRRS) virus-positive sow farm. Pigs were fed a 3-phase feeding program as in Exp. 1. Three levels of SBM (low, medium, or high) and 2 phytase levels (600 or 2,600 FTU) were combined to create 6 dietary treatments in a 3 × 2 factorial arrangement. Inclusion of SBM was 15.0, 22.5, and 30.0% for Phase 1 and 20.0, 27.5, and 35.0% for Phase 2 for low, medium, and high SBM, respectively, and 29.0% for the common Phase 3 diet. Inclusion of SBM did not affect growth performance. The percentage of pigs removed for medical treatment linearly declined with increasing SBM levels ( = 0.04). High-SBM diets tended ( < 0.10) to decrease stool firmness during d 4 and 5 and high phytase tended ( < 0.10) to improve stool firmness on d 2 and 4. Analyzed PRRS titers in saliva samples collected on d 20 and 42 confirmed the PRRS status of the pigs; however, viral load was not impacted by dietary treatments ( ≥ 0.11). Results indicate that SBM levels in early nursery diets can be increased without decreasing growth performance and may be favorable in pigs originating from PRRS-positive sow farms by reducing costs of medical treatments. Supplementation of phytase at superdose levels can improve growth performance independently from the level of SBM in the diet.

QTL for seed protein and amino acids in the Benning × Danbaekkong soybean population.

KEY MESSAGE: We identified QTL associated with protein and amino acids in a soybean mapping population that was grown in five environments. These QTL could be used in MAS to improve these traits. Soybean, rather than nitrogen-containing forages, is the primary source of quality protein in feed formulations for domestic swine, poultry, and dairy industries. As a sole dietary source of protein, soybean is deficient in the amino acids lysine (Lys), threonine (Thr), methionine (Met), and cysteine (Cys). Increasing these amino acids would benefit the feed industry. The objective of the present study was to identify quantitative trait loci (QTL) associated with crude protein (cp) and amino acids in the 'Benning' × 'Danbaekkong' population. The population was grown in five southern USA environments. Amino acid concentrations as a fraction of cp (Lys/cp, Thr/cp, Met/cp, Cys/cp, and Met + Cys/cp) were determined by near-infrared reflectance spectroscopy. Four QTL associated with the variation in crude protein were detected on chromosomes (Chr) 14, 15, 17, and 20, of which, a QTL on Chr 20 explained 55 % of the phenotypic variation. In the same chromosomal region, QTL for Lys/cp, Thr/cp, Met/cp, Cys/cp and Met + Cys/cp were detected. At these QTL, the Danbaekkong allele resulted in reduced levels of these amino acids and increased protein concentration. Two additional QTL for Lys/cp were detected on Chr 08 and 20, and three QTL for Thr/cp on Chr 01, 09, and 17. Three QTL were identified on Chr 06, 09 and 10 for Met/cp, and one QTL was found for Cys/cp on Chr 10. The study provides information concerning the relationship between crude protein and levels of essential amino acids and may allow for the improvement of these traits in soybean using marker-assisted selection.

Energy concentration of high-oil corn varieties for pigs.

Growth performance and utilization of nutrients and energy in three high-oil corn varieties (5.4 to 9.7% ether extract) and regular corn (4.2% ether extract) were compared in three experiments using growing pigs. Twenty-four 25-kg crossbred barrows were used in Exp. 1 to evaluate nutrient and energy digestibility in the three high-oil corn varieties and regular corn. Four diets were formulated to contain 97% of one of four varieties of corn (Control, TC1, TC2, and X122 varieties) and 3% minerals and vitamins. Digestibilities of nitrogen and ether extract were similar (P > .05) for regular corn and all three varieties of high-oil corn. The digestible energy concentrations (kcal/g; as-fed basis) for control, TC1, TC2, and X122 corn varieties were 3.29, 3.57, 3.4, and 3.41, respectively, with control lower (P < .05) than TC2 or X122 and TC1 higher (P < .05) than TC2 or X122. Metabolizable energy concentrations averaged 98.4% of digestible energy concentrations. In Exp. 2, four diets formulated to contain 79% of one of the four corn varieties, 18.25% 48% CP soybean meal, 2.45% vitamins and minerals, and .3% lysine.HCl were fed to 24 crossbred barrows (six pigs per diet) in a nutrient and energy balance study similar to the Exp. 1. Results were similar to those obtained in Exp. 1. The same four diets that were used in Exp. 2 were fed to 40 (10/diet) 20-kg crossbred pigs (20 barrows and 20 gilts) in a 28-d growth performance study (Exp. 3). Gain:feed ratios were .39, .43, .42, and .42 and growth rates (kg/d) were .68, .74, .70, and .72 for diets containing control, TC1, TC2, and X122 corn varieties, respectively. These translate to 8 to 10% improvement in feed efficiency and a numerical improvement in weight gain (3 to 9%) when high-oil corn was fed as compared with control corn. The results of nitrogen, ether extract, and energy balance and feeding experiments with growing pigs indicate efficient utilization of nutrients in diets containing high-oil corn.

Digestion responses to low oligosaccharide soybean meal by ileally-cannulated dogs.

We investigated digestion responses to conventional and low oligosaccharide soybean meal (SBM) incorporation into diets for dogs. Five female dogs were fitted with T-type cannulas at the terminal ileum and fed five diets in a 5 x 5 Latin square design. Corn grain + poultry meal-based diets containing different levels and types of SBM (0% SBM, 18.55% conventional SBM, 18.55% low oligosaccharide SBM, 37.1% conventional SBM, 37.1% low oligosaccharide SBM) were formulated. Each period consisted of 11 d (7-d diet adaptation; 4-d collection of ileal digesta and feces). Intakes of DM, OM, CP, fat, and GE were not affected (P > .10) by treatment. Higher (P < .01) starch intakes and higher (P < .05) total dietary fiber (TDF) intakes were noted for dogs fed diets with SBM. Digestibilities of CP (P < .04) and starch (P < .002) at the ileum were higher for dogs fed the higher levels of SBM. Ileal digestibilities of most individual amino acids followed the CP response. Total tract digestibility of CP was higher (P < .006) in dogs fed the SBM diets. There were no significant differences in nutrient digestibilities between conventional and low oligosaccharide SBM. Stachyose and raffinose intakes by dogs were decreased dramatically (P < .001) as a result of substituting the low oligosaccharide SBM for conventional SBM at the higher dietary concentration, although sucrose intake by dogs fed low oligosaccharide SBM was higher (P < .001). Galactinol was present in low oligosaccharide SBM but not in conventional SBM. Total tract digestion of all oligosaccharides was near 100%. The low oligosaccharide SBM was digested as extensively, but no better than, conventional SBM.

Effect of a synthetic antimicrobial agent on the rates of synthesis and degradation of liver and skeletal muscle proteins in growing rats.

A double isotope technique was used to evaluate the effects of a synthetic antimicrobial compound (carbadox) upon the synthesis and degradation of rat liver and muscle proteins. Trials 1 and 2 used, respectively, 20 and 12 male Sprague-Dawley rats with average initial weights of 75 and 81 g. A 16% crude protein corn-soybean diet without or with carbadox (55 ppm) was fed. Rats were randomly assigned to diets which were fed 10 days prior to the initial isotope (14C-lysine) injection. The second isotope injection (3H-lysine) was made 3 days after the 14C-lysine injection in trial 1, 6 days in trial 2. Four hours after the second injection, the rats were killed and the right and left quadriceps and a sample of liver were removed. Total protein from the right quadriceps was prepared via a boiling trichloroacetic acid (TCA) extraction procedure. The left quadriceps was separated into myofibrillar and sarcoplasmic protein fractions via a KCl salt gradient. In both trials, gains were similar across treatments, but markedly reduced during the injection periods. Gain/feed prior to injection was greater (P less than 0.05) for carbadox-fed rats. In both trials right quadriceps 3H-incorporation (expressed as 3H cpm/mg protein) and relative degradation (3H cpm/14C cpm) were not affected by dietary carbadox. The sarcoplasmic and myofibrillar protein fractions were also not significantly affected. However, in both trials liver protein 3H-incorporation was enhanced (P less than 0.025) by carbadox, while liver protein degradation was affected (P less than 0.001) only in trial 2.

A technique for monitoring nutrient absorption in the conscious, unrestrained pig.

A surgical preparation allowing for the determination of apparent absorption in the conscious, unrestrained pig is described. The technique allows the collection of blood from the hepatic portal vein and vena cava, as well as the simultaneous determination of rate of flow through the portal vessel. A chronic electromagnetic blood flow probe is placed around, and a mechanical, hydraulically activated sampling needle attached to, the hepatic portal vein. An indwelling catheter is placed within the vena cava. By simultaneously determining nutrient concentration of hepatic portal and vena cava blood and then multiplying their difference by the rate of blood flow through the hepatic portal vein, one can make a point-in-time estimate of apparent absorption from the gastrointestinal tract.

Response of young chicks to raw, defatted, Kunitz trypsin inhibitor variant soybeans as sources of dietary protein.

Two trials, using 264 8-day-old male crossbred chicks, were conducted to evaluate the nutritional value of two trypsin-inhibitor (Kunitz) variant soybeans. These two variants, designated PI 157440 (PI) and number 661, have lower trypsin-inhibitor activities than do US commercially grown soybean cultivars such as Amsoy 71. Raw PI, 661, and Amsoy 71 soybeans were defatted and then compared to a commercially processed solvent extracted soybean meal (SBM) using purified diets with soybeans or SBM as the sole source of protein. Trials 1 and 2, respectively, were of 6 and 7 days duration. SBM was superior to each of the raw meals. In Trial 1, gain/feed was higher from PI than from Amsoy 71. In Trial 2, gain and gain/feed were higher (P < .05) from PI and 661 than from Amsoy 71. Pancreas weight as a percent of body weight reflected the trypsin-inhibitor intake. The addition of .3% DL-methionine to each diet improved (P < .05) gain and gain/feed. In Trial 2 gain and gain/feed from PI plus methionine was greater (P < .05) than from 661 plus methionine. In both trials, raw PI plus 3% methionine produced gain and gain/feed comparable to SBM without added methionine.