Effects of Replacing Supplemental Sucrose with Beef During Mid to Late Gestation on Maternal Health and Fetal Development using a Sow Biomedical Model

ObjectivesThe objectives of this study were to investigate the influence of substituting supplemental sucrose with beef on maternal health and fetal development using a sow biomedical model.Materials and MethodsMultiparous crossbred sows (BW = 222 kg; n = 21; rep = 3) were individually housed from d 30 to 111 (± 0.58) of gestation. From d 30 to 39, a complete sow ration (corn-soybean meal-based, CSM) was fed at 1% of d 30 gestational BW. On d 39, daily dietary ration was adjusted to 1% of d 39 gestational BW which was fed daily at 0700 h from d 40 to 110 (± 0.58). Sows were randomly assigned to 1 of 4 isocaloric supplement treatments; 126 g CSM to serve as a control (CON, n = 5), 110 g cooked ground beef (BEEF, n = 6), 85.5 g sucrose (SUCR, n = 5), or 54.8 g BEEF and 42.7 g SUCR (B+S, n = 5). Dietary supplements were fed daily at 1100, 1500, and 1800 h from d 40 to 110 (± 0.58). Blood was collected via jugular venipuncture from sows on d 29 and 111 (± 0.58). Blood chemistry was immediately analyzed, and serum samples were collected for lipid panel and insulin concentrations. Bodyweights were measured on d 30, 39, 54, 68, 82, 96, and 111 (± 0.58). Tenth rib and last rib SQ fat depth were measured on d 35, 70, and 110 (± 0.58) via ultrasound. Sows were euthanized on d 111 (± 0.58). Reproductive tract (RT), pancreas, kidney, liver, heart, heart fat, lung, semimembranosus and abductor (SM), and semitendinosus (ST) weights were collected and recorded from each sow. Two median weight male and female fetuses were selected from each sow for tissue collections. Fetal tissue collection was the same as sows with the addition of testes and no RT weight. A repeated measures design, with sow as the repeated measure, was modeled using the MIXED procedure of SAS using compound symmetry variance covariance matrix. Sow data fixed effects were replicate, sow, and treatment. Fetal data fixed effects were replicate and fetal weight category. Covariates were determined for each individual trait depending on goodness of fit. A treatment by day interaction was used for sow data while a treatment by sex interaction was used for fetal data. Alpha level was 0.05.ResultsDietary treatment did not influence gestational BW (P ≥ 0.99), SQ fat depth (P ≥ 0.09), blood chemistry (P ≥ 0.21), or serum concentrations (P ≥ 0.07). Dietary treatment did not influence sow tissue weight (P ≥ 0.42). Compared with CON, BEEF fetuses had greater fetal BW (P = 0.01), crown to rump length (P = 0.01), nose to crown length (P < 0.01), heart girth (P = 0.02), and abdominal girth (P = 0.05). Dietary treatment did not influence fetal growth characteristics of median weight male and female fetuses (P ≥ 0.23). Compared with BEEF, SUCR fetuses had heavier liver weights (31.43 ± 2.06 and 40.13 ± 2.09, respectively; P = 0.04). There was a dietary treatment by sex interaction for fetal kidney weight with BEEF males having lighter kidney weights compared with all other interactions (P = 0.03). Dietary treatment did not influence any other fetal tissue weight (P ≥ 0.09).ConclusionBeef and/or sucrose supplementation during mid-to-late gestation has minimal effects on swine maternal health and fetal development. Differences in fetal liver and kidney weights should be examined further. Further research is needed to determine the effect of gestational supplementation on human health and development.

Effects of post-mortem aging time and type of aging on palatability of low marbled beef loins

The study objective was to evaluate the effect of post-mortem aging period (14 to 49days), dry vs. wet (D vs W) type of aging on the palatability of bone-in (BI) beef short loins (n=96) and boneless (BL) strip loins (n=96) possessing United States Department of Agriculture marbling scores between Slight and Small. Warner-Bratzler shear force (WBSF) scores decreased linearly over time (P=0.0001). WBSF was not influenced by aging method or loin type. Aged flavor was higher for DBL than for DBI with WBL and WBI intermediate. Dry aging strip loins increase aged flavor yet did not improve beefy flavor compared to wet aging. Based on objective data and panelist's scores for tenderness, juiciness and aged flavor, a boneless, 28days wet aged strip steak, cooked to 71°C would provide the best combination of eating satisfaction and value.

Impact of maternal physical activity during gestation on porcine fetal, neonatal, and adolescent ovarian development

To determine how exercise from mid to late (days 40-104) gestation impacts offspring body, uterine and ovarian weight, and ovarian cell proliferation at three different developmental stages, Yorkshire gilts were either exercised by walking (EX) or not exercised (CON). In parity 1, ovaries and uteri were collected from the heaviest (H) and lightest (L) neonates and adolescent (6 mo) offspring. In parity 2, mothers were assigned the same treatment groups, and ovaries and uteri were collected from H and L fetuses on day 94 of gestation. Body weight was greater (P < 0.02) for H than L fetuses and neonates but not affected by EX treatment at any developmental stage. Ovarian weight in L but not H neonates was greater (P < 0.02) in EX than CON. Labeling index (LI; percentage of proliferating cells) was greater (P < 0.01) in cortex than medulla regions of fetal and neonatal ovaries. In fetal ovaries, EX enhanced LI (P < 0.01), and LI was greater (P < 0.01) in H compared with L offspring. In adolescent ovaries, LI was greatest (P < 0.01) in healthy antral and least in atretic antral follicles, and LI was greater (P < 0.01) in granulosa than theca cells of healthy antral follicles. Thus, exercise increased LI in fetal but not neonatal or adolescent ovaries. Although maternal exercise during gestation influences fetal and neonatal ovarian development, impacts on fertility remain unknown.

Consumer evaluation of palatability characteristics of a beef value-added cut compared to common retail cuts

The objectives of this study were to educate consumers about value-added beef cuts and evaluate their palatability responses of a value cut and three traditional cuts. Three hundred and twenty-two individuals participated in the beef value cut education seminar series presented by trained beef industry educators. Seminar participants evaluated tenderness, juiciness, flavor, and overall like of four samples, bottom round, top sirloin, ribeye, and a value cut (Delmonico or Denver), on a 9-point scale. The ribeye and the value cut were found to be similar in all four attributes and differed from the top sirloin and bottom round. Correlations and regression analysis found that flavor was the largest influencing factor for overall like for the ribeye, value cut, and top sirloin. The value cut is comparable to the ribeye and can be a less expensive replacement.

Evaluation of feedlot cattle working chute behavior relative to temperament, tenderness, and postmortem proteolysis

The objective was to investigate if the association between working chute behavior and beef tenderness found in our previous study is related to protein degradation and calpain system activity. Crossbred steers (n=183) allotted to 16 pens were weighed every 28 d. Temperament was evaluated as exit velocity (EV), chute score (CS), and catch score (CAPS). Between 14 and 16 mo of age (606±52 kg), steers were harvested. Strip steaks were collected and aged for 14 d. Subsamples were collected at 36 h and 7d postmortem and analyzed for calpastatin activity, μ-calpain autolysis, and troponin-T degradation. Shear force (WBSF) was correlated (P<0.05) with calpastatin activity and measurements of troponin-T. Calpastatin activity, μ-calpain autolysis, and troponin-T measurements did not correlate with the measurements of EV, CS, and CAPS. Therefore, activation of the calpain system or differences in protein degradation did not appear to influence the differences in tenderness that are correlated with working chute behavior.

Predicting beef tenderness using color and multispectral image texture features

The objective of this study was to investigate the usefulness of raw meat surface characteristics (texture) in predicting cooked beef tenderness. Color and multispectral texture features, including 4 different wavelengths and 217 image texture features, were extracted from 2 laboratory-based multispectral camera imaging systems. Steaks were segregated into tough and tender classification groups based on Warner-Bratzler shear force. The texture features were submitted to STEPWISE multiple regression and support vector machine (SVM) analyses to establish prediction models for beef tenderness. A subsample (80%) of tender or tough classified steaks were used to train models which were then validated on the remaining (20%) test steaks. For color images, the SVM model correctly identified tender steaks with 100% accurately while the STEPWISE equation identified 94.9% of the tender steaks correctly. For multispectral images, the SVM model predicted 91% and STEPWISE predicted 87% average accuracy of beef tender.

Effects of pea chips on pig performance, carcass quality and composition, and palatability of pork

Pea chips are produced as a by-product when field peas are processed to produce split peas for human consumption. The objective of this experiment was to test the hypothesis that inclusion of pea chips in diets fed to finishing pigs does not negatively influence pig growth performance, carcass composition, and the palatability of pork. A total of 24 barrows (initial BW: 58.0 ± 6.6 kg) were allotted to 1 of 4 treatments and fed early finishing diets for 35 d and late finishing diets for 35 d. A corn-soybean meal (SBM) control diet and 3 diets containing pea chips were formulated for each phase. Pea chips replaced 33.3, 66.6, or 100% of the SBM in the control diet. Pigs were housed individually, and all pigs were slaughtered at the conclusion of the experiment. Overall, there were no differences (P > 0.11) in final BW, ADFI, and G:F of pigs among treatments, but there was a quadratic response in ADG (P = 0.04), with the smallest value observed in pigs fed the control diet. Dressing percentage linearly decreased (P = 0.04) as pea chips replaced SBM in diets, but there were no differences (P > 0.20) among treatments in HCW, LM area, 10th-rib backfat, lean meat percentage, and marbling. Likewise, pH in loin and ham, drip loss, and purge loss were not influenced (P > 0.13) by treatment. However, there was a quadratic response (P = 0.08) in 24-h pH in the shoulder, with the smallest value present in pigs fed the diet, in which 66.6% of the SBM was replaced by pea chips. Subjective LM color and Japanese color score standard were reduced (quadratic, P = 0.03 and 0.05, respectively) and LM b* values and hue angle were increased (quadratic, P = 0.09 and 0.10, respectively) when pea chips replaced SBM in the diets. Ham L* (quadratic, P = 0.04), a* (linear, P = 0.02), b* (quadratic, P = 0.07), color saturation (linear, P = 0.02), and hue angle (quadratic, P = 0.05) were increased when pea chips replaced SBM. However, there were no differences (P > 0.16) in shoulder and fat color. Moreover, cook loss percentage, shear force, juiciness, and pork flavor of pork chops were not different (P > 0.10) among treatments, but tenderness of pork chops linearly decreased (P = 0.04) as SBM replaced pea chips. It is concluded that all the SBM in diets fed to growing-finishing pigs may be replaced by pea chips without negatively influencing growth performance or carcass composition. However, pigs fed pea chips will have pork chops and hams that are lighter, and chops may be less tender if pigs are fed pea chips rather than corn and SBM.

Closed-chamber transepidermal water loss measurement: microclimate, calibration and performance

The importance of transepidermal water loss (TEWL) as a measure of the skin barrier is well recognized. Currently, the open-chamber method is dominant, but it is increasingly challenged by newer closed-chamber technologies. Whilst there is familiarity with open-chamber characteristics, there is uncertainty about the capabilities of the challengers. The main issues are related to how microclimate affects TEWL measurements. The aim of this paper is to provide a framework for understanding the effects of microclimate on TEWL measurement. Part of the problem is that TEWL measurement is indirect. TEWL is the diffusion of condensed water through the stratum corneum (SC), whereas TEWL methods measure water vapour flux in the air above the SC. This vapour flux depends on (i) the rate of supply of water to the skin surface and (ii) the rate of evaporation of water from the skin surface. Rate (i) is a skin property (TEWL), rate (ii) is a microclimate property. The controlling rate for the combined process is the lower of the above two rates. Therefore, TEWL instruments measure TEWL only when TEWL is the rate-limiting process. Another problem is that SC barrier property and SC hydration are affected by the microclimate adjacent to the skin surface. This is discussed insofar as it affects the measurement of TEWL. The conclusion is that such changes occur on a timescale that is long compared with TEWL measurement times. An important aspect of TEWL measurement is calibration. We present an analysis of the traditional wet-cup method and a new droplet method that is traceable and has been independently verified by a standards laboratory. Finally, we review performance indicators of commercial closed-chamber instruments with reference to open-chamber instruments. The main findings are that TEWL readings correlate well, but there are significant differences in the other aspects of performance.

Effects of dry matter intake restriction on diet digestion, energy partitioning, phosphorus retention, and ruminal fermentation by beef steers

Two experiments were conducted to determine the effects of DMI restriction on diet digestion, ruminal fermentation, ME intake, and P retention by beef steers. In Exp. 1, twelve Angus x steers (average initial BW = 450 +/- 18 kg) were assigned randomly to 1 of 3 diets that were formulated to promote a 1.6-kg ADG at intake levels corresponding approximately to 100% (ad libitum, AL), 90% (IR90), or 80% (IR80) of ad libitum DMI. In Exp. 2, twelve crossbred steers (average initial BW = 445 +/- 56 kg) fitted with ruminal cannulae were randomly assigned to 1 of 2 diets that were formulated to promote a 1.6-kg ADG at AL or IR80. All diets delivered similar total NE, MP, Ca, and P per day. During both experiments, fecal DM output by IR80 was less (P </= 0.03) than that of AL; IR90 was similar (P = 0.51) to AL during Exp. 1. Digestion of DM by IR80 cattle was greater (P </= 0.03) than that of AL during both experiments; IR90 was similar (P = 0.31) to AL during Exp. 1. Metabolizable energy intake was similar (P >/= 0.20) among treatments during both experiments, whereas P retention was similar (P >/= 0.46) among treatments during Exp. 1. Total VFA and the molar proportion of acetate of AL were greater (P </= 0.03) than that of IR80 during Exp. 2; however, IR80 had a greater (P = 0.03) molar proportion of propionate. Under the conditions of these studies, restricting DMI while holding NE, ruminally degradable protein, and MP intakes constant decreased fecal DM output and changed ruminal fermentation patterns in finishing steers. Improvements in performance associated with programmed-feeding regimens of the type studied here do not appear to be related to changes in diet digestion or ME intake.

Diet modifications to improve finishing pig growth performance and pork quality attributes during periods of heat stress

A total of 196 barrows (88 kg) were used in a 2 x 2 factorial arrangement of treatments and housed in a facility (seven pigs per pen) where temperatures cycled between 27 and 35 degrees C. Treatments consisted of (as-fed basis) two CP levels (13.6 or 11.3%) and two levels of added fat (1 or 8%). Diets were formulated to the same true digestible lysine:ME ratio (1.68 g of lysine/Mcal of ME). Diets were fed and growth variables were measured until pigs reached 114 kg of BW. Ham and LM (loin) 24-h pH (PH24), and light reflectance (CIE L*, and a*, and b*, and hue angle) were taken after slaughter. Additionally, loins were removed and measured for i.m. fat, moisture, glycolytic potential, and subjected to a 7-d retail display evaluation that measured pH, light reflectance, and subjective color and odor score. The remaining boneless lumbar loin segment was vacuum-sealed for 14 d and subsequently measured for pH, light reflectance, and color. Pigs fed the high-CP, low-fat diet had a lower ADG than all other treatments (P = 0.06). High-fat feeding resulted in improved ADG (CP x Fat; P = 0.06) and G:F (Fat effect; P < 0.01). Higher fat and lower protein levels both increased final BF (P = 0.07). Pigs fed the low-CP diets had lower ham PH24 (P < 0.01). Loin PH24 was higher with high fat feeding (P = 0.10). Additionally, pigs fed high fat diets had lower L* values on the ham face and cut loin 24 h after slaughter (Fat effect; P <or= 0.02). These loin color differences were maintained through the 7-d retail display and 14-d storage period. There were no differences in loin i.m. fat or moisture content; however, high-fat feeding tended to decrease loin glycolytic potential (P = 0.11). These results suggest that in a hot environment, decreased CP content improved finishing pig ADG when dietary fat supplementation was low. High dietary fat inclusion during heat stress improved ADG and G:F, especially when CP level was elevated. High-fat diets fed in a hot environment increased pork color intensity by decreasing the glycolytic potential at slaughter and elevating muscle pH.

Serum hormone concentrations relative to carcass composition of a random allotment of commercial-fed beef cattle12

Cattle (n = 995 steers and 757 heifers) were randomly selected from a commercial abattoir (Emporia, KS) to determine the relationships between USDA quality and yield grade characteristics and serum concentrations of leptin, IGF-I, and GH. Animals were randomly selected postexsanguination on the slaughter line on 4 occasions (March, May, August, and January). Blood was collected at exsanguination and transported to the University of Missouri for analysis. Sex and hide color were recorded. Carcass data included HCW, 12th-rib fat thickness, KPH, LM area, and marbling score, which were collected from each carcass approximately 24 h postmortem. Average serum leptin concentrations were greater (P = 0.008) for heifers (11.9 ng/mL) than steers (10.9 ng/mL). Heifers had lighter carcasses (331.9 vs. 352.2 kg, P < 0.001), greater 12th-rib fat measurements (1.3 vs. 1.1 cm, P < 0.001), greater KPH (2.5 vs. 2.4%, P < 0.001), and more marbling (Small(40) vs. Small(10), P < 0.001) than steers. Positive correlations (P < 0.01) existed between leptin concentration and marbling score (r = 0.28), 12th-rib fat depth (r = 0.37), KPH (r = 0.23), and USDA yield grade (r = 0.32). Negative correlations were found between leptin and IGF-I (r = -0.11; P < 0.001) and leptin and GH (r = -0.32; P < 0.001). Negative correlations (P < 0.01) were observed for IGF-I and KPH (r = -0.23) and marbling score (r = -0.20), whereas GH was most highly negatively correlated with KPH (r = -0.23; P < 0.001). Leptin concentration accounted for variation (P < 0.001) in a model separating least squares means across USDA quality grade, separating USDA standard (8.5 ng/mL), select (10.3 ng/mL), low choice (12.2 ng/mL), and upper 2/3 choice/prime (>12.9 ng/mL) carcasses. There was no difference (P = 0.31) observed in leptin concentrations between the upper 2/3 choice and prime carcasses (12.9 and 14.2 ng/mL, respectively). Relationships within endocrine profiles and between endocrine concentrations and carcass quality characteristics may prove to be a useful tool for the prediction of beef carcass composition.

Growth rate, body composition, and meat tenderness in early vs. traditionally weaned beef calves

One hundred forty spring-born Angus x Gelbvieh and purebred Angus steers were selected for study as early weaned (EW; average age at weaning = 90 +/- 30 d) or traditionally weaned (TW; average age at weaning = 174 +/- 37 d) steers that were non-implanted or implanted (Synovex-S, Fort Dodge Animal Health, Overland Park, KS). Initially, steers were sorted by age, sire, and farm, and then allotted randomly in a 2 x 2 factorial arrangement of treatments of EW implanted (EWI), EW nonimplanted (EWN), TW implanted (TWI), or TW nonimplanted (TWN). Ultrasound measurements (US) of LM area (LMA), 12th rib fat thickness (US-BF), and marbling (US-M) were collected every 28 d during the time that steers were on feed. At 202 d of age, EW calves had larger US-LMA, US-BF, and BW than TW calves (37.9 vs. 32.3 cm2, 0.38 vs. 0.26 cm, and 271.6 vs. 218.9 kg, respectively; P < 0.001). At slaughter, EW calves had heavier HCW (290.4 vs. 279.7 kg, respectively; P < 0.05) and greater USDA marbling scores (51.25 vs. 46.26, respectively; P < 0.05) than TW calves; more EW steers graded USDA Choice or greater (P = 0.05). However, no differences were detected in BW (P = 0.15), LMA (P = 0.39), BF (P = 0.45), or liver abscess scores (P = 0.41). Twenty-four implanted steers were selected from the original group of 140 and sorted into two slaughter groups of 12. Twelve implanted steers from each weaning group, matched in slaughter BW but differing in age, were subsampled at slaughter to assess the effect of weaning age and chronological age on muscle tenderness. Younger animals had lower Warner-Bratzler shear force values (P < 0.001) than older calves after 14 d of postmortem aging; however, no differences were found in tenderness after 21 d of aging. Furthermore, there was greater variance (P < 0.001) in Warner-Bratzler shear force values among younger, EW steers vs. older, TW steers. These data provide evidence that early weaning of beef calves may be used as a tool to more effectively manage the cow-calf production system without compromising the quality of the offspring.

Growth performance, carcass composition, quality, and enhancement treatment of fresh pork identified through deoxyribonucleic acid marker-assisted selection for the Rendement Napole gene1,2

Progeny (n = 70) from unrelated, DNA tested, Rendement Napole carrier (RN-/rn+) Hampshire sires, and DNA tested, Rendement Napole normal (rn+/rn+) Yorkshire dams were genotyped for the segregating RN- allele via DNA marker-assisted methodology. Six slaughter groups ensued, with littermates all being represented within the same slaughter group. Boneless pork loins were removed from right carcass sides after a 48-h chill at 2 degrees C. The anterior portions of the loins were not enhanced, whereas the posterior sections were enhanced with a solution containing 0.5% sodium chloride and 0.5% sodium tripolyphosphate to 110% of their initial weight. Carcasses of carrier pigs had less (P < 0.05) 10th rib fat depth and a greater (P < 0.01) percentage carcass lean than carcasses of normal pigs. Postmortem LM pH of carrier pigs was lower (P < 0.002) at 3, 6, 12, and 24 h, and tended to be lower (P = 0.062) at 48 h compared with that of normal animals. Samples of LM from carrier pigs had greater (P < 0.01) glycolytic potential values, drip loss percentages, and a* values, and lower pH values at fabrication than LM from normal pigs. No genotype differences (P > 0.05) were found for LM lactate, L*, or b* values. Nonenhanced semimembranosus samples from carrier pigs exhibited greater (P < 0.05) purge loss percentages and L* values, and lower (P < 0.01) pH values than samples from normal pigs. Enhanced LM samples exhibited greater (P < 0.05) drip and purge loss percentages, greater pH, and lower L* values at fabrication, regardless of Napole status. These findings suggest that the Napole gene has a positive influence on carcass leanness but detrimental effects for lean quality, which were often further compounded when meat was subjected to enhancement treatment.

Pork quality attributes associated with bilateral carcass variation

The objective of this study was to identify bilateral differences in pork carcass quality as influenced by single leg shackling and suspension of electrically stunned pigs. Fifty-six Genepacker x EB market barrows (118 kg) were rendered unconscious and insensible to pain via electrical stimulation. Pigs were then shackled and suspended by the right hind leg before exsanguination and remained suspended until scalding. Initial (45-min) pH values of the LM at the 10th to 11th rib interface were different (P = 0.016); shackled side loins possessed a greater i.m. pH than those loins associated with the free side of the carcass (6.26 vs. 6.10). At 24 h postmortem, loins from the shackled side had lower (P < 0.001) L* values than loins from the free side in both the sirloin (53.08 vs. 57.61) and blade (54.61 vs. 57.09) regions. Additionally, b* values were greater (P < 0.001) for loins from the shackled side than loins from the free side in the center (13.81 vs. 13.01) and blade (14.72 vs. 13.68) regions, and in the blade region, a* values were greater (P < 0.001) in the LM from the shackled side than loins from the free side (7.37 vs. 6.26). Moreover, LM chops of loins from the shackled side that were aged 21 d were rated less (P < 0.05) tough (2.74 vs. 3.95) and more (P < 0.05) juicy (4.24 vs. 3.19) than chops from the free-hanging side. However, these differences were not evident after 41 d aging. From the results of this study, it can be concluded that bilateral differences exist within the LM of a pork carcass and that these differences are likely associated with the single-leg shackling and suspension of electrically stunned pigs.

The effect of dietary ractopamine concentration and duration of feeding on growth performance, carcass characteristics, and meat quality of finishing pigs

A total of 400 barrows from Dekalb EB and 83 terminal sires mated to 43 and 45 maternal lines were used to evaluate the effects of dietary ractopamine (RAC; Paylean, Elanco Animal Health, Greenfield, IN) concentrations (0, 5, 10, or 20 ppm; as-fed basis) and feeding durations (6 to 34 d) on growth, efficiency, carcass, and meat quality characteristics of finishing pigs. Barrows were weighed and sorted into five weight blocks, each block consisting of 16 pens (five pigs per pen). Weight blocks were allocated to feeding duration treatments and assigned consecutively by weight from lightest to heaviest to represent 34, 27, 20, 13, and 6 d on test, respectively. The lightest and heaviest blocks averaged 79.8 and 103.8 kg, respectively, at the start of the test. Within a weight block, pens (four per treatment) were randomly assigned to one of four dietary concentrations of RAC in a basal diet containing 18.5% CP and 1.13% lysine. The experiment-wide target slaughter weight was 109 kg, and pigs and feeders were weighed weekly. Weight blocks (80 barrows per block) were slaughtered at a commercial packing plant after 6, 13, 20, 27, or 34 d on test. Overall, RAC supplementation improved (P < 0.05) ADG; however, ADG was not different (P > 0.08) from controls for pigs fed 5, 10, and 20 ppm RAC for 27, 34, and 6 d, respectively. During each feeding period, RAC-fed pigs had improved (P < 0.05) G:F, and, after 20, 27, and 34 d on test, pigs fed 20 ppm RAC had greater (P < 0.05) G:F compared with those fed 0 or 5 ppm RAC. Hot carcass weight was increased (P < 0.05) by RAC feeding after 13 and 27 d of feeding, and by feeding 10 and 20 ppm RAC after 20 d of feeding. After 34 d, pigs fed 20 ppm RAC had heavier (P < 0.05) hot carcass weight than pigs fed 10 ppm RAC. Fat-free lean estimates and the 10th-rib LM area were increased (P < 0.05) by feeding 10 and 20 ppm RAC after 27 d, and by feeding 20 ppm RAC after 34 d compared with controls. Japanese and American color scores, as well as L*, a*, and b* values of the LM, were not affected (P > 0.11) by 5 and 10 ppm RAC compared with controls during each feeding period. Visual marbling score for the LM was decreased (P < 0.05) when RAC was fed at 10 and 20 ppm compared with 0 ppm RAC when fed for 34 d. Dietary RAC improved growth performance at all feeding durations, whereas carcass composition was improved at longer feeding durations. In addition, 5 and 10 ppm RAC did not affect objective and subjective measures of pork quality.

The effects of the antioxidant lipoic acid on beef longissimus bloom time

The objective of this study was to evaluate the influence of lipoic acid (LA) on beef LM steak bloom time, as well-as to characterize bloom time in the CIE L*, a*, and b* color space over a 93-min period. Thirty-two Simmental steers were supplemented with LA for 21 d immediately before slaughter at levels of 0, 8, 16, or 24 mg of LA/kg BW (eight steers per treatment). Lipoic acid was mixed with liquid paraffin, allowed to solidify, prilled, and top-dressed over a standard finishing diet. Steers were slaughtered at the University of Missouri abattoir in four groups of eight (two steers per treatment) over a 2-wk period. After a 24-h chill at 4 degrees C, the right LM was removed from each carcass. One 2.54cm steak was removed from the anterior portion of the LM, and its color characteristics (CIE L*, a*, and b*) were measured immediately with a standardized spectrocolorimeter. Color measurements were taken every 3 min thereafter for a total of 93-min. Hue angle (true red) and chroma (color saturation) were calculated from the color measurements. Addition of LA to the diet had no effect on bloom time (P = 0.67). When treatment means were analyzed, the addition of 24 mg of LA/kg BW to the diet resulted in higher (lighter) L* values (P < 0.05) compared with other treatments, whereas the addition of 16 mg of LA/kg BW to the diet caused lower hue angles (more true red; P < 0.05) when compared with other treatments. Addition of LA to the diet did not affect a* (P = 0.13) and b* (P = 0.18) values or chroma (P = 0.62). In the absence of treatment effects, bloom times for all treatments were pooled, and L* values did not change (P > 0.05) during the 93-min bloom time; however, a* and chroma values increased for 9 min and plateaued after 12 min (P < 0.01). Similarly, b* values increased (P < 0.01) for the first 6 min, and after 9 min, no further increase in yellowness was detected. Bloom time had little effect on hue angle, which stabilized after 3 min. Supplementing steers with the antioxidant LA for 21 d had no effect on the bloom time of beef LM; however, higher levels of supplemental LA affected L* values and hue angles of beef.

Evaluation of procedures to predict fat-free lean in swine carcasses12

The objectives were to develop equations for predicting fat-free lean in swine carcasses and to estimate the prediction bias that was due to genetic group, sex, and dietary lysine level. Barrows and gilts (n = 1,024) from four projects conducted by the National Pork Board were evaluated by six procedures, and their carcass fat-free lean was determined. Pigs of 16 genetic groups were fed within weight groups one of four dietary regimens that differed by 0.45% in lysine content and slaughtered at weights between 89 and 163 kg. Variables in equations included carcass weight and measures of backfat depth and LM. Fat-free lean was predicted from measures of fat and muscle depth measured with the Fat-O-Meater (FOM), Automated Ultrasonic System (AUS), and Ultrafom (UFOM) instruments, carcass 10th-rib backfat and LM area (C10R), carcass last-rib backfat (CLR), and live animal scan of backfat depth and LM area with an Aloka 500 instrument (SCAN). Equations for C10R (residual standard deviation, RSD = 2.93 kg) and SCAN (RSD = 3.06 kg) were the most precise. The RSD for AUS, FOM, and UFOM equations were 3.46, 3.57, and 3.62 kg, respectively. The least precise equation was CLR, for which the RSD was 4.04 kg. All procedures produced biased predictions for some genetic groups (P < 0.01). Fat-free lean tended to be overestimated in fatter groups and underestimated in leaner ones. The CLR, FOM, and AUS procedures overestimated fat-free lean in barrows and underestimated it in gilts (P < 0.01), but other procedures were not biased by sex. Bias due to dietary lysine level was assessed for the C10R, CLR, FOM, and SCAN procedures, and fat-free lean in pigs fed the lowlysine dietary regimen was overestimated by CLR, FOM, and SCAN (P < 0.05). Positive regressions of residuals (measured fat-free lean minus predicted fat-free lean) on measured fat-free lean were found for each procedure, ranging from 0.204+/-0.013 kg/kg for C10R to 0.605+/-0.049 kg/kg for UFOM, indicating that all procedures overestimated fat-free lean in fat pigs and underestimated it in lean pigs. The pigs evaluated represent the range of variation in pigs delivered to packing plants, and thus the prediction equations should have broad application within the industry. Buying systems that base fat-free lean predictions on measures of carcass fat depth and muscle depth or area will overvalue fat pigs and undervalue lean pigs.

Creatine monohydrate supplemented in swine finishing diets and fresh pork quality: III. Evaluating the cumulative effect of creatine monohydrate and alpha-lipoic acid1,2

The objective of this study was to evaluate short-duration supplementation of alpha-lipoic acid (ALA) and creatine monohydrate (CMH) to improve fresh pork quality. Forty-eight commercial hybrid barrows were blocked by BW and randomly allotted to one of four treatments: 1) no CMH or ALA; 2) supplementation of 24 g of CMH(-1) x pig(-1) x d(-1); 3) supplementation of 600 mg ALA(-1) x pig(-1) x d(-1); or 4) combined CMH and ALA supplements. Twelve pigs per treatment were individually penned with ad libitum access to water and a finishing diet. Treatments were hand-fed to individual pigs daily (divided into three equal doses) for 5 d before slaughter at 113 kg BW in two separate groups of 24 pigs each. Intramuscular pH was recorded at 45 min postmortem and again at 24 h in the ham semimembranosus (SM) and the longissimus muscle (LM) between the 10th and 11th rib. A Meatcheck (SFK Technology, Peosta, IA) conductivity probe was inserted in the same anatomical locations as pH measurement, providing an index value (PY) from 0 to 100 (a higher index value indicates more intact muscle cells and higher water-holding capacity). Color (L, a, b values) measurements were obtained at 24 h postmortem on the ham gluteus medius (GM), SM, and LM. Two 2.54-cm-thick loin chops were removed from the loin for determination of Warner-Bratzler shear force and glycolytic potential. The intact SM and the posterior portion of the boneless loin were vacuum-packaged and stored for 7 d to determine purge loss. Creatine-supplemented pigs had a higher (P = 0.03) PY value in the SM (66.67) at 45 min postmortem than either ALA, singularly (63.50), or in the combined CMH/ALA (62.27) treatments. (A higher PY index indicates superior water-holding capacity.) Lipoic acid supplementation resulted in the highest pH at 45 min (P = 0.029). These results justify further evaluation of the potential positive influence of supplementing alpha-lipoic acid to improve pork quality.

Short- and long-term influence of perinatal dexamethasone treatment on swine growth

The objective was to evaluate the effects of perinatal dexamethasone (Dex) treatment on postnatal growth in pigs. Experiment 1: 42 piglets were assigned according to birth weight and sex to receive either Dex (1 mg/kg body weight) or sterile saline (Control; equivalent volume) i.m. within 1h of birth. Body weights were recorded weekly and at sacrifice (day 18). Birth weights (1.43 +/- 0.05 kg) did not differ between treatment groups (P > 0.19). At day 18, Dex pigs were heavier than Control pigs (5.46 +/- 0.24 and 4.45 +/- 0.26 kg, respectively). Serum IGF-1 was 17.3% higher in Dex pigs (P < 0.04) compared to Controls. For serum GH, there was a treatment x sex interaction (P < 0.04) with GH being 51% lower in Dex males compared to Control males, and no differences in females. Experiment 2: 71 pigs were assigned according to birth weight and sex to receive either Dex (2 mg/kg body weight) or sterile saline (Control; equivalent volume) i.m. within 1 h of birth. Body weights were recorded weekly until weaning (day 21) and then every 14th day until market weight. Birth weights (1.53 +/- 0.03 kg) did not differ (P > 0.35) between treatment groups or sexes. Dexamethasone increased growth from birth to market weight by 4.15%. Carcass weights were not different (P > 0.34) between Dex (89.9 +/- 1.17 kg) and Control pigs (88.6 +/- 1.36 kg). Overall, Dex enhanced growth in pigs from birth to market weight with minimal effects on carcass and meat quality.

Serum concentrations of leptin in six genetic lines of swine and relationship with growth and carcass characteristics

The objective of this study was to evaluate the relationship between serum concentrations of the hormone leptin with growth and carcass traits insix distinct breeds of pigs entered into the 2000 National Barrow Show Sire Progeny Test. Breeds evaluated were Berkshire (n = 131), Chester White (n = 33), Duroc (n = 40), Landrace (n = 23), Poland China (n = 26), and Yorkshire (n = 41). Serum samples were collected and assayed for concentrations of leptin at entry into test (On-Test Leptin) at 34 +/- 6.7 kg of live weight and again 24 h prior to harvest (Off-Test Leptin) at 111 +/- 3.1 kg of live weight. Carcass measurements taken included hot carcass weight, carcass length, backfat, longissimus muscle area (LMA), longissimus pH, Hunter L-value, chemically determined intramuscular fat (IMF), and subjective color, marbling, and firmness scores. Average daily gain, IMF percentages, and water-holding capacity (WHC) were also determined. On-Test Leptin concentrations were not different (P > 0.10) between swine breeds; however, Off-Test Leptin concentrations did differ (P < 0.001) across genotype. Berkshire had the greatest Off-Test Leptin concentrations (6.58 +/- 0.43 ng/mL), and Duroc and Yorkshire had the lowest (3.49 and 3.96 +/- 0.68 ng/mL; respectively). In addition, Off-Test Leptin concentrations were correlated with average daily gain (r = 0.29; P < 0.001), last-rib fat thickness (r = 0.48; P < 0.001), 10th rib backfat (r = 0.52; P < 0.001), LMA (r = -0.33; P < 0.001), percent fat-free carcass lean (r = -0.51; P < 0.001), and WHC (r = 0.15; P < 0.05). Off-Test Leptin concentrations also differed by gender, with barrows having greater (P < 0.001) serum concentrations of leptin than gilts (6.55 +/- 0.48 vs 3.35 +/- 0.44). Differences exist between breeds of pigs in a manner consistent with breed-specific traits for growth, leanness, and quality; thus, leptin may serve as a useful marker for selection or identification of specific growth and carcass traits.

Creatine monohydrate supplementation and the quality of fresh pork in normal and halothane carrier pigs

The objective of this research was to examine the impact of supplementation with creatine monohydrate (CMH) on the quality of various muscles from normal and heterozygous halothane carrier pigs. Twenty-nine crossbred pigs, 16 normal (NN) and 13 halothane carrier (Nn) genotypes, were supplemented with 0 or 25 g x pig(-1) x d(-1) of CMH for 5 d before slaughter. Supplemented pigs gained 2.26 kg more weight (P < 0.05) during 5 d of supplementation. There were trends (P < 0.10) toward higher objective marbling scores and lower cooking loss for supplemented pigs. The 45-min pH was 0.27 units higher (P < 0.05) for supplemented pigs in the semimembranosus; CMH supplementation did not influence (P > 0.05) drip loss or muscle composition. Supplementation with CMH also resulted in lower L* values in two ham muscles, semitendinosus (5.15 units) (P < 0.05) and semimembranosus (1.95 units) (P < 0.10) for Nn carcasses. Genotype had significant effects on most quality indicators, with Nn carcasses producing lower-quality lean as evidenced by less desirable subjective and objective color and higher drip losses. Genotype also affected the composition of several muscles, with the NN carcasses having more fat and less moisture.

Creatine monohydrate supplemented in swine finishing diets and fresh pork quality: II. Commercial applications

The objectives of this study were to determine the value of supplementing creatine monohydrate (CMH) in a complete swine finishing ration and determining its effects on meat quality. Crossbred barrows (n = 59) were allotted five pens per treatment with three pigs per pen. Dietary treatments, including 20 g CMH x pig(-1) x d(-1) fed for 5, 10, or 15 d before slaughter, were compared to control pigs that received no CMH. The basal diet was a corn-soybean meal finishing diet. At 123.5 kg, pigs were delivered to a commercial packing plant (80 km) and slaughtered according to industry practices. After a 24-h chill at 4 degrees C, right-side loins were collected from the fabrication line and vacuum-packaged for delivery to the University of Missouri Meat Lab. Hams were scanned for lean content by a primal cut electromagnetic scanner. After scanning, ham pH and light reflectance (L*, a*, b*) were obtained on the gluteus medius muscle. Loin pH and light reflectance were obtained at the 10/11th-rib juncture. The posterior section of the boneless loin was weighed, vacuum-packaged, and stored for 7 d at 1 degree C. After aging, light reflectance, weights, and Warner/Bratzler shear force measurements were taken. A linear trend (P = 0.071) was observed for ham 24-h L* values, and a cubic trend was observed for ultimate loin pH (P = 0.102). Hunter L* values of the longissimus possessed a negative linear contrast (P = 0.009) after aging, revealing that the loins of those animals treated for 10 and 15 d exhibit higher L* values. A cubic trend (P = 0.057) was shown for percentage of moisture lost as purge; 5- and 10-d treatments were intermediate to control and 15-d treatments. Warner/Bratzler shear force measurements for chops aged 7 d increased in a linear fashion (P = 0.024). This data suggests that 5-d supplementation of CMH before slaughter improves several pork quality attributes. However, it seems that supplementing CMH in swine diets for 10 or 15 d could reduce the quality of fresh pork.

Creatine monohydrate supplemented in swine finishing diets and fresh pork quality: I. A controlled laboratory experiment

Creatine monohydrate (CMH) was fed during the final stage of growth to determine its effects on fresh pork quality. Twenty-four Duroc-sired market hogs (107 kg) were individually penned and fed a corn-soybean finishing diet containing 0.55% lysine with 2% added choice white grease. Treatments consisted of a control diet (control) tested against two durations of CMH-supplemented diets (25 g CMH x pig(-1) x d(-1)) fed for 5 (5 d) or 10 (10 d) d before slaughter. Eight pigs were used per treatment. Pigs were slaughtered on day 11 of treatment (118 kg). Postmortem pH was measured in the loin (10th rib) and ham semimembranosus at 45 min (pH1) and 24 h (pH2). At 24 h, Hunter L* values were taken at the 10th rib and the ham semimembranosus. At 48 h, drip loss was determined from the loin (8th rib) and semimembranosus. Percentage of moisture, crude fat, and crude protein were determined for loin (9th rib) and semimembranosus. Treatment 2 semimembranosus tended to have a higher pH1 (P = 0.083) and pH2 (P = 0.05) than controls. Although not statistically different, 10 d semimembranosus had the highest proportion of moisture and lowest CP:moisture ratio, suggesting greater myofiber hydration. No statistical differences were detected across treatments for loin pH1, pH2, CP:moisture, or drip loss. Loins and semimembranosus from 5 d pigs had a numerically higher proportion of chemically determined i.m. fat, suggesting optimal intramuscular creatine phosphate saturation may allow for more energy to be stored as i.m. fat. Standard deviations of ham L* value means for 5 d (SD = 2.53) and 10 d (SD = 2.05) were 26 and 48% lower than controls (SD = 3.95). Standard deviations of loin L* value for 5 d (SD = 2.53) and 10 d (SD = 2.53) were 51 and 64% lower than controls (SD = 1.86). These results suggest that CMH supplementation buffers early postmortem and ultimate pH decline in the semimembranosus, which may reduce 48-h moisture loss.

Total body electrical conductivity (TOBEC) measurement of compositional differences in hams, loins, and bellies from conjugated linoleic acid (CLA)-fed stress-genotype pigs

This study was designed to observe the effects of conjugated linoleic acid (CLA) supplementation on lean content of pork carcass primal cuts (hams, loins, and bellies) and to determine the ability of total body electrical conductivity (TOBEC) to predict lean content. A total of 64 crossbred growing-finishing barrows were placed on a control (soybean oil) or CLA (0.75%) diet at an average weight of 40 kg. Pigs were penned in pairs according to diet and stress genotype (negative, carrier, and positive) and slaughtered at 115 kg. Stress genotype was included because of known variations in lean content. Hams (IMPS 401A; n = 64), loins (IMPS 410; n = 24), and bellies (IMPS 408; n = 63) were fabricated from carcasses at 24 h postmortem and scanned for electromagnetic (EM) absorption by a MQ-25 EM scanner. Each wholesale cut was scanned in triplicate at 2.5 MHz to yield a peak mean average (PMA) value then separated into lean, fat, bone, and skin components. Bellies were skinned prior to scanning then subjected to a belly bar firmness test before dissection. Supplementation with CLA had no effect (P > 0.05) on lean ham composition. Regression analysis was used for lean weight prediction using primal weight and PMA value as predictors. Lean content prediction of hams by TOBEC resulted in an R2 of 0.80. Loins from CLA-supplemented pigs exhibited increased lean weight (P < 0.05) and PMA values (P < 0.05) compared to controls. Lean prediction of loins by TOBEC resulted in an R2 of 0.66. Bellies from CLA-supplemented pigs had a higher percentage of moisture (P < 0.03) and protein (P < 0.01) and decreased percentage of lipid (P < 0.01). The R2 values from the regression analysis predicting protein, moisture, protein + moisture, and fat-free soft tissue composition of the skinless bellies were 0.67, 0.68, 0.71, and 0.78, respectively.

Using current on-line carcass evaluation parameters to estimate boneless and bone-in pork carcass yield as influenced by trim level

The objective of this study was to develop prediction equations for estimating proportional carcass yield to a variety of external trim levels and bone-in and boneless pork primal cuts. Two hundred pork carcasses were selected from six U.S. pork processing plants and represented USDA carcass grades (25% USDA #1, 36% USDA #2, 25% USDA #3, and 14% USDA #4). Carcasses were measured (prerigor and after a 24 h chill) for fat and muscle depth at the last rib (LR) and between the third and fourth from last rib (TH) with a Hennessy optical grading probe (OGP). Carcasses were shipped to Texas A&M University, where one was randomly assigned for fabrication. Selected sides were fabricated to four lean cuts (ham, loin, Boston butt, and picnic shoulder) then fabricated progressively into bone-in (BI) and boneless (BL) four lean cuts (FLC) trimmed to .64, .32, and 0 cm of s.c. fat, and BL 0 cm trim, seam fat removed, four lean cuts (BLS-OFLC). Total dissected carcass lean was used to calculate the percentage of total carcass lean (PLEAN). Lean tissue subsamples were collected for chemical fat-free analysis and percentage carcass fat-free lean (FFLEAN) was determined. Longissimus muscle area and fat depth also were collected at the 10th and 11th rib interface during fabrication. Regression equations were developed from linear carcass and OGP measurements predicting FLC of each fabrication point. Loin muscle and fat depths from the OPG obtained on warm, prerigor carcasses at the TH interface were more accurate predictors of fabrication end points than warm carcass probe depth obtained at the last rib or either of the chilled carcass probe sites (probed at TH or LR). Fat and loin muscle depth obtained via OGP explained 46.7, 52.6, and 57.1% (residual mean square error [RMSE] = 3.30, 3.19, and 3.04%) of the variation in the percentage of BI-FLC trimmed to .64, .32, and 0 cm of s.c. fat, respectively, and 49.0, 53.9, and 60.7% (RMSE = 2.91, 2.81, and 2.69%) of the variation in the percentage of BL-FLC trimmed to .64, .32, and 0 cm of s.c. fat, respectively. Fat and loin muscle depth from warm carcass OGP probes at the TH interface accounted for 62.4 and 63.5% (RMSE = 3.38 and 3.27%) of the variation in PLEAN and FFLEAN, respectively. These equations provide an opportunity to estimate pork carcass yield for a variety of procurement end point equations using existing on-line techniques.

Pork carcass composition derived from a neural network model of electromagnetic scans

We used an advanced computer logic system (NETS 3.0) to decipher electromagnetic (EM) scans in lieu of traditional linear regression for estimation of pork carcass composition. Fifty EM scans of pork carcasses were obtained on-line (prerigor) at a swine slaughter facility. Right sides were cut into wholesale parts and dissected into fat, lean, and bone to obtain total dissected carcass and primal cut lean. In this study, the input layer consisted of 81 nodes (80-point EM scan curve and warm carcass weight), one hidden layer of 42 nodes, and an output layer consisting of one node, which were run separately for outputs of ham, loin, or shoulder lean. The hidden layer connected to the output of total lean contained 50 nodes. Thirty-five scans were used for training of the network. The new network was then tested with 15 previously unseen input/output pairs. Separate neural networks were developed for the estimation of dissected total carcass, ham, loin, and shoulder lean. The NETS configuration improved on linear regression equations for estimation of total carcass lean by .31 kg, ham lean by .284 kg, and shoulder lean by .148 kg. Our results show that advanced computer logic systems have the capacity to improve upon traditional linear regression equations for prediction of pork carcass composition.

Evaluation of electronic technology to assess lamb carcass composition

Accurate price signals are essential for producers of American lamb to ensure production of uniformly lean animals. Development of carcass merit-pricing systems will require the use of objective technology for assessing carcass composition or lean distribution. The objective of this study was to evaluate electronic technologies for accurate determination of lamb carcass composition. Lambs (n = 106) were selected as a representation of U.S. market lambs that transcended geographic location, sex, breed, carcass weight, yield grade, and production system. The independent variables used to predict lamb composition varied with the technology. The electronic technologies tested included realtime ultrasound, optical reflectance probe, bioelectrical impedance analysis, and electromagnetic scanning (TOBEC). All technologies, except realtime ultrasound, were tested on warm (prerigor) carcasses and repeated after a 24-h chill. Longitudinal ultrasonic scans of fat and muscle tissue depth and grading probe fat depths were marginal predictors of proportional carcass yield. The TOBEC measurements often accounted for more variability associated with kilograms of dissected lean and percentage of carcass lean than did carcass weight. Equations from TOBEC measurements were the most accurate predictors of weight and percentage of dissected and fat-free lean. Bioelectrical impedance measurements of resistance and reactance combined with carcass weight were also good predictors of carcass composition. Prediction of carcass lean distribution by measures of TOBEC were the most accurate for prediction of leg lean. The implications of usefulness of these technologies will depend on the commitment of the U. S. sheep industry in development of a lamb price discovery system based on carcass composition.

Assessment of lamb carcass composition from live animal measurement of bioelectrical impedance or ultrasonic tissue depths

Market weight lambs, average weight 52.5 kg (+/-6.1), were used to evaluate nontraditional live animal measurements as predictors of carcass composition. The sample population (n = 106) represented U.S. market lambs and transcended geographic location, breed, carcass weight, yield grade, and production system. Realtime ultrasonic (RU) measurements and bioelectrical impedance analysis (BIA) were used for development and evaluation of prediction equations for % boneless, closely trimmed primal cuts (BCTPC), weight or % of dissected lean tissue (TDL), and chemically derived weight or % fat-free lean (FFL). Longitudinal ultrasonic images were obtained parallel to the longissimus thoracis et lumborum (LTL), positioning the last costae in the center of the transducer head. Images were saved and fat and LTL depths were derived from printed images of the ultrasonic scans. Bioelectrical impedance analysis was administered via a four-terminal impedance plethysmograph operating at 800 microA at 50 kHz. Impedance measurements of whole-body resistance and reactance were recorded. Prediction equations including common linear measurements of live weight, heart girth, hindsaddle length, and shoulder height were also evaluated. All measurements were taken just before slaughter. Bioelectrical impedance measurements (as compared to RU and linear measurements) provided equations for %BCTPC, TDL, %TDL, FFL and %FFL with the highest R2 and lowest root mean square error. Even though BIA provided the best equations of the three methodologies tested, prediction of proportional yield (%BCTPC, %TDL, and %FFL) was marginal (R2 = .296, .551, and .551, respectively). Equations combining BIA, RU, and linear measurements greatly improved equations for prediction of proportional lean yield.

Alternative pork carcass evaluation techniques: I. Differences in predictions of value

Dissected and predicted wholesale and lean boneless values for 154 pork carcasses representing seven genotypes with substantial variation in carcass composition and percentage of lean were determined. Dissected carcass value was determined using a component pricing model, and four alternative models were specified to predict that value. The models included measurements from a ruler (RULER) and two carcass evaluation technologies, Hennessy probe (PROBE) and electromagnetic scanner (EMS1). A combination of the PROBE and EMS1 models (EMS2) was also used. For wholesale value, R2 were .40, .70, .59, and .74, and the RSD were 8.18, 5.77, 6.76, and 5.38 ($/100 kg of carcass value) for RULER, PROBE, EMS1, and EMS2, respectively. For lean boneless value, the R2 were .41, .73, .59, and .74, and the RSD were 8.34, 5.67, 6.99, and 5.51 ($/100 kg of carcass value) for RULER, PROBE, EMS1, and EMS2, respectively. The results indicate that a combination of probe and electromagnetic scanner measurements provided the best fit to dissected value.

Alternative pork carcass evaluation techniques: II. Statistical analysis of error attributable to sex, genotype, and weight

Carcasses of 154 hogs representing seven genotypes with substantial variation in carcass composition and percentage of lean were completely dissected and analyzed. Measurements from a ruler, Hennessy probe, and electromagnetic scanner were each used to predict wholesale and lean boneless carcass value. Error, defined as dissected value minus predicted value, due to the omission of sex, genotype, weight, and their interactions was estimated for each model. The errors were significantly different from zero for the models using ruler and electromagnetic scanning measurements separately (P < .01). Errors due to sex, genotype, weight, and their interactions were greatest for the less lean barrows. A combination of probe and electromagnetic scanner measurements resulted in the least error. The value of barrows with low percentage of lean was consistently overpredicted, whereas the value of leaner gilts was underpredicted for the models using ruler and electromagnetic scanning separately (P < .001).

Electromagnetic scanning of pork carcasses in an on-line industrial configuration

The objective of this study was to test and validate electromagnetic scanning of whole pork carcasses in an on-line, integrated, industrial configuration. The electromagnetic (EM) scanner was installed in two pork processing facilities (Plant A and Plant B). Plant A was a small pork fabrication plant that further processed chilled pork carcasses. Carcasses were delivered to Plant A by refrigerated trucks. The amount of EM energy absorbed by the carcasses was recorded as they were conveyed through the EM field. A plot of the absorption units over time (EM scan curve) was used to obtain predictive variables for estimating carcass and primal cut composition. Forty-eight whole, chilled carcasses (Group A) were electromagnetically scanned and conveyed onto the fabrication line. The average percentage carcass lean for Group A was 49.1% (range = 36.5 to 59.5%). Right carcass sides were removed from the processing line, fabricated into primal cuts, and dissected into fat, lean, and bone. Prediction equations were developed from EM scans for weight of total dissected carcass lean (R2 = .830; root mean square error = 1.80 kg), percentage of carcass lean (R2 = .820; root mean square error = 2.29%), and weight of dissected ham, longissimus muscle, and shoulder lean. In Plant B, the electromagnetic scanner was installed at the end of a pork slaughter line to ensure carcass scanning at a consistent carcass temperature. Fifty whole, pre-rigor eviscerated carcasses (Group B) were electromagnetically scanned before entering the chill cooler where fat and loin tissue depths were obtained by an optical grading probe. The average percentage carcass lean for Group B was 46.7% (range = 30.1 to 57.3%). Prediction equations were developed from EM scans for weight of total dissected carcass lean (R2 = .904; root mean square error = 1.59 kg), percentage of carcass lean (R2 = .863; root mean square error = 2.05%), and weight of dissected ham, loin, and shoulder lean. Statistical equations developed for the prediction of dissected primal cut lean were superior from EM scans of Group B (prerigor) carcasses. Electromagnetic scanning proved more statistically efficient than optical probes for predicting weight of dissected carcass lean and percentage of carcass lean. Statistical comparison of EM scan equations from Groups A and B are not completely valid because two different populations of carcasses were tested at different times of the year. The results of this study show that EM scanning has the potential to accurately predict pork carcass composition in a fully automated, on-line industrial configuration.

Electromagnetic scanning to predict lamb carcass composition

The electromagnetic scanner generates a constant, low-level electromagnetic field (2.5 MHz) within a large plexiglass tube. The amount of electromagnetic (EM) energy transferred (to the carcass) is highly related to lean tissue. A plot of the absorption units over distance can be used to assess the total mass of lean tissue and of the respective primal cuts. The difference in curve height between two points (D), peak phase absorption, and linear carcass measurements (pre-rigor, HCWT or post-rigor, CWT carcass weight, and carcass length, LENG) were used to predict total dissected lean (TOTLEAN), dissected leg lean (LEGLEAN), and percentage of dissected carcass lean (PERLEAN). Twenty-one pre-rigor and 22 post-rigor (24 h chill) lamb carcasses, average weight 26.8 (+/- 4.2 kg) and 26.4 (+/- 4.1 kg) kg, respectively, were evaluated from measurements of total body electrical conductivity (TOBEC). Two geometric orientations were tested for statistical accuracy in this study: A) each carcass entered the EM tunnel rear leg first, on its left lateral side, neck facing the right side of the tunnel; and B) each carcass entered the EM tunnel rear leg first, breast down, and neck up. Orientation A proved more statistically efficient for pre-rigor carcasses, and orientation B was more desirable for post-rigor carcasses. Multiple-regression models involving HCWT, LENG, and a single D measure accounted for 98.0 and 95.0%, respectively, of the total variation in pre-rigor carcass TOTLEAN and LEGLEAN in A.(ABSTRACT TRUNCATED AT 250 WORDS)

Bioelectrical impedance analysis for the prediction of fat-free mass in lambs and lamb carcasses

Ninety-eight commercial crossbred lambs, average weight 55.1 kg (+/- 4.95), were used to evaluate bioelectrical impedance analysis (BIA) as a prediction method for fat-free tissue from live lambs and lamb carcasses. Lambs were transported to the abattoir, restricted from feed for 10 h, weighed (LWt), and measured for body resistance (Rs, ohms), body reactance (Xc, ohms), and distance between detector terminals (L, cm). Following slaughter, hot carcasses were weighed (HCWt; average 31.4 +/- 2.8 kg) and impedance measurements of Rs, Xc, and L were recorded from readings on the dorsal and lateral sides of the carcasses. Temperatures (average = 39.2 degrees C) were recorded. Carcasses were chilled for 24 h. Cold carcass weights (CWt; average 31.1 +/- 2.8 kg) and temperatures (average = 1.0 degrees C) were recorded and BIA measurements were repeated. Carcasses were split down the midline and right sides were ground three times and sampled for chemical analysis of fat, moisture, ash, and protein. Fat-free mass (FFM) was calculated as [Wt-(Wt x %Fat)]. Fat-free soft tissue (FFST) was calculated as the sum of carcass chemical protein and carcass water. Regression equations predicting fat-free tissue for the live lambs (FFMlive and FFSTlive), hot carcasses (FFMhot and FFSThot), and cold carcasses (FFMcold and FFSTcold) were developed. The independent variables LWt, Rs, and Xc accounted for 77.7% (residual mean square error [RMSE] = 1.97 kg) of the variation in FFMlive and 78.6% (RMSE = 1.78 kg) of the variability of FFSTlive.(ABSTRACT TRUNCATED AT 250 WORDS)

Faith healing

This article has attempted to show the relevance of faith and prayer to the healing arts. Whilst its frame of reference differs from that of the medical scientist, its application is not incompatible with conventional medical practice. It springs from a belief that all healing ultimately resides with God, who acts through divinely appointed laws to energize the natural healing processes of the body. Through faith and prayer, attunement is possible with God resulting in an energy flow to the patient. This belief is supported by scientific evidence. Faith healing supports the concept of 'healing of the whole person', and challenges the medical scientist and practitioner to develop a greater awareness of the 'unknown factors' working in recoveries of patients beyond normal medical expectation.

Stereochemical studies on medicinal agents. 21. Investigation of the role of conformational factors in the action of diphenylpropylamines. Synthesis and analgetic potency of 5-methylmethadone diastereomers

The synthesis of racemic threo- and erythro-5-methylmethadone (3a and 3b, respectively) was carried out and the solution conformation of each isomer was investigated through pKa and NMR studies. The data indicate that 3a-HCl exists exclusively in an internally hydrogen-bonded conformation while the erythro isomer 3b-HCl is present as a mixture of conformations. The erythro racemate 3b was found to possess 5.4 times the analgetic potency of (+/-)-methadone in contrast to the threo racemate 3a which was inactive and devoid of antagonist activity. The fact that the inactive racemate 3a contains the 5S,6R stereoisomer, which combines the configurations found in the more active enantiomers of methadone and isomethadone, suggests that the chiral centers do not behave as independent units and that conformational factors are playing an important role in governing stereoselectivity. These results, when analyzed together with earlier reports, suggest that one of the pharmacophoric conformations of the diphenylpropylamine analgetics possesses an antiperiplanar-like disposition of the Ph2CCOEt and +NHMe2 groups.