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R N Goodwin

Publications and source records attributed to R N Goodwin.

11 recordsLinked to original sources

Influence of lipid content on pork sensory quality within pH classification.

The objective of this project was to determine the contribution of lipid content to textural and sensory properties of fresh pork within defined pH classifications. Pigs (n = 1,535; from 248 sires and 836 dams) from the 1991, 1992, and 1994 National Barrow Show Sire Progeny Test were used in this study. The test included purebred Berkshire (107), Chester White (113), Duroc (249), Hampshire (220), Landrace (165), Poland China (101), Spotted (181), and Yorkshire (399) barrows (901) and gilts (634). Diets were uniform across breeds within test. The halothane (Hal 1843) genotype (1346 NN and 189 Nn) was determined. Pigs were slaughtered at 105 kg of BW, and samples of the LM were obtained from each carcass at the 10th rib. Star probe, sensory traits, and lipid content were determined on the LM from each pig. A pH classification of LM was assigned as follows: class A, > 5.95, n = 186; class B, > or = 5.80 to 5.95, n = 236; class C, > or = 5.65 to 5.80, n = 467; class D, > or = 5.50 to 5.65, n = 441; class E, < 5.50, n = 205. Data were analyzed using a mixed linear model including pH classification, test, sex, halothane genotype, breed, and breed x sex interaction as fixed effects, with sire and dam within breed included as random effects. Correlations were determined within pH class. Lipid content was a significant source of variation for models predicting star probe values in class C and D and for chewiness in class B, C, and D. Increasing lipid content tended to increase sensory tenderness in pH class D. Sensory tenderness was not affected by lipid content in pH class A, B, or E. Lipid content was not a significant source of variation for juiciness scores within any pH class. Intramuscular lipid is correlated with sensory texture traits primarily in classes C and D. Within class C and D, correlations indicate that increasing lipid content is associated with high sensory tenderness, low sensory chewiness, and low star probe values. It is concluded that lipid content is a small source of variation in texture and tenderness of pork loin with pH between 5.80 and 5.50, but not at a greater or lesser pH.

Animals↗

Effects of breed, sex, and halothane genotype on fatty acid composition of pork longissimus muscle.

The objective of this study was to estimate the effects of breed, sex, and halothane genotype on fatty acid composition and several fatty acid indices of lipid extracted from porcine LM. Purebred Yorkshire (n = 436), Duroc (n = 353), Hampshire (n = 218), Spotted (n = 187), Chester White (n = 173), Poland China (n = 124), Berkshire (n = 256), and Landrace (n = 187) pigs (n = 1,934; 1,128 barrows and 806 gilts) from 1991, 1992, 1994, and 2001 National Barrow Show Sire Progeny Tests were used. Pigs were classified as the HAL-1843 normal (NN) genotype (n = 1,718) or the HAL-1843 carrier (Nn) genotype (n = 216). For statistical analysis, a mixed model was used that included fixed effects of breed, sex, halothane genotype, test, slaughter date, interaction of breed x sex, and random effects of sire and dam within breed. Breed significantly affected the concentration of individual fatty acids, total lipid content, and the values of several fatty acid indices of LM. Duroc pigs had the greatest (P < 0.01) content of total SFA. Total MUFA concentration in Poland China pigs was greater (P < 0.05) than in all other breeds except the Spotted (P > 0.05). The concentrations of total PUFA were greater (P < 0.01) in Hampshire, Landrace, and Yorkshire pigs compared with those of other breeds. Significant sex differences for individual fatty acids were detected. Compared with gilts, barrows had greater (P < 0.01) concentrations of SFA and MUFA but lower (P < 0.01) total PUFA. Halothane genotype was a significant source of variation for the percentages of some fatty acids. Pigs with the carrier (Nn) genotype had lower concentrations of SFA (P < 0.05) and MUFA (P < 0.01) but a greater concentration of PUFA (P < 0.01) compared with NN pigs. There were significant negative correlations between total lipid content and individual PUFA and significant positive correlations between lipid concentration and most individual SFA and MUFA. In conclusion, the results suggest that breed and sex are important sources of variation for fatty acid composition of LM.

Anesthetics, Inhalation↗

National Pork Producers Council Maternal Line National Genetic Evaluation Program: a comparison of sow longevity and trait associations with sow longevity.

Data from the National Pork Producers Council Maternal Line National Genetic Evaluation Program were used to compare longevity of sows from 6 commercial genetic lines and to estimate the phenotypic associations of sow longevity with gilt backfat thickness, ADG, age at first farrowing, litter size at first farrowing, litter weight at first farrowing, average feed intake during lactation, and average backfat loss during lactation. The lines evaluated were American Diamond Genetics, Danbred North America, Dekalb-Monsanto DK44, Dekalb-Monsanto GPK347, Newsham Hybrids, and National Swine Registry. The data set contained information from 3,251 gilts, of which 17% had censored longevity records (sows lived longer than 6 parities). The line comparison was carried out by analyzing all lines simultaneously. Because the survival distribution functions differed among genetic lines, later analyses were carried out separately for each genetic line. All analyses were based on the non-parametric proportional hazard (Cox model). Dekalb-Monsanto GPK347 sows had a lower risk of being culled than sows from the other lines. Moreover, the shape of the survival distribution function of the Delkab-Monsanto GPK347 line was different from the other 5 lines. The Dekalb-Monsanto 347 line had lower culling rates because they had lower gilt reproductive failure before the first parity than gilts from the other lines. Within line, sows with lower feed intake and greater backfat loss during lactation had a shorter productive lifetime. Thus, producers should implement management practices having positive effects on sow lactation feed intake. Additionally, the swine genetics industry is challenged to simultaneously improve efficiency of gain of their terminal market pigs and to obtain high feed intake during lactation of their maternal lines for future improvement of sow longevity. Recording sow feed intake and backfat loss during lactation in nucleus and multiplication breeding herds should be considered. Between-line differences in this study indicate that it is possible to select for sow longevity, but more research is needed to determine the most efficient selection methods to improve sow longevity.

Adipose Tissue↗

National Pork Producers Council Maternal Line Genetic Evaluation: a comparison of growth and carcass traits in terminal progeny.

The objective of this study was to compare growth and carcass traits of 1,252 progeny of six commercially available dam lines included in the National Pork Producers Council Maternal Line Evaluation Project. Lines compared included one maternal line supplied by each of American Diamond Swine Genetics (ADSG), Danbred NA (DB), two lines supplied by Monsanto Choice Genetics (DK and GPK347), Newsham Hybrids (NH), and Landrace x Large White females supplied by the National Swine Registry (NSR). All females were mated to DB, Duroc-Hampshire terminal sires. Traits analyzed were ADG from 56 to 115 kg live weight, days to 115 kg, backfat thickness measured at the 10th rib, carcass length, dressing percent, and 10th-rib LM area. Carcass traits were adjusted to a carcass weight of 85 kg. The statistical model included fixed effects of maternal line, sex, farrowing group, and finishing unit (farm). All two-way interactions among main effects were tested and removed from final models because they were not significant. In addition, because they were not significant, effects of farm and farrowing group were removed from models for carcass length and 10th-rib backfat thickness, and farm was removed from the model for LM area. Least squares means for ADG ranged from 0.74 to 0.79 kg/d. The GPK347 line had lower ADG and greater days to 115 kg than all other lines (P < 0.05). The ADSG (P < 0.05) and NH (P < 0.01) progeny had lower ADG than DK progeny. The DK line had the fewest days to 115 kg (P < 0.05). Progeny for the DB and NH lines had the least 10th-rib backfat, differing from ADSG, DK, and GPK347 (P < 0.05). Pigs from DB females had the greatest dressing percent, differing from ADSG, DK, GPK347, and NH (P < 0.05). The GPK347 had a lower dressing percent than all other lines (P < 0.05). Progeny of DB females had the greatest LM area, differing from ADSG, DK, GPK347, and NSR (P < 0.05). Offspring from ADSG and GPK347 had the smallest LM area; however, GPK347 and NSR did not differ. Differences in carcass length were statistically significant; however, actual differences were small. Economic weights for these traits relative to reproductive traits must be considered in integrated economic analyses to properly compare differences among lines in net economic value for specific markets.

Animals↗

The National Pork Producers Council Maternal Line National Genetic Evaluation Program: a comparison of six maternal genetic lines for female productivity measures over four parities.

Litter (n = 8,424) and female performance records were collected in two breed-to-wean production units in order to evaluate genetic line differences for sow longevity and maternal performance over four parities. Lines evaluated were American Diamond Genetics, Danbred North America, Dekalb-Monsanto DK44, Dekalb-Monsanto GPK347, Newsham Hybrids, and National Swine Registry. Females within a line were derived from a minimum of 65 sires, 197 dams (three dams per sire), and a maximum of three daughters per dam, except in the GPK347, which were produced using semen from 12 Nebraska Index boars mated with Dekalb-Monsanto Line 34 females. All lines expressed 100% maternal heterosis. Mixed model statistical procedures were used with fixed effects including genetic line, parity, production unit, and two-way interactions. Random effects included a contemporary week of production and female for repeated records. Lactation length (average 15 d) was included as a linear covariate where appropriate. In total, 3,599 females entered as early-weaned pigs, 3,283 entered the breeding herd, 2,592 farrowed at least a single litter, and 1,656 and completed four parities. Line (P < 0.001) and parity (P < 0.001) effects were observed for virtually all traits measured. Ranges of genetic line differences averaged across parities were 1.76 pigs for total born, 1.45 pigs born alive, and 0.31 stillborn pigs per litter. Ranges of line differences in total and live litter weight were 1.4 and 1.3 kg, respectively. Ranges among lines, within Parities 1 through 4, for litter size at weaning were 0.56, 1.08, 0.91, and 0.64 pigs per litter, respectively. Line differences for weight (33.8 kg) and backfat depth (6.4 mm) at farrowing, lactation feed intake (8.7 kg), weight loss (5.0 kg), and backfat loss (0.87 mm) were observed. Extended wean-to-estrus interval was related to variation in weight, feed intake, and backfat loss in all lines except the GPK347. The GPK347 females farrowed and weaned the largest number of pigs, ate less feed in lactation, and lost more backfat and weight during lactation, yet they had the largest litters and the shortest wean-to-estrus intervals. Line x parity interactions existed for many traits due to small rank changes, but in general, the high- and low-ranked lines did not change. Genetic line differences in reproductive efficiency through four parities exist and must be recognized when choosing a female line.

Adipose Tissue↗

Breed differences and genetic parameters of myoglobin concentration in porcine longissimus muscle.

An evaluation of porcine longissimus myoglobin concentration was conducted to determine breed and gender differences for myoglobin content, estimate genetic parameters for myoglobin concentration, and determine the relationship between myoglobin content and objective measures of muscle color. Data from centrally tested (n = 255), purebred Yorkshire (42), Duroc (61), Hampshire (17), Chester White (28), Berkshire (67), Poland China (28), and Landrace (12) barrows and gilts from the 1999 National Barrow Show Sire Progeny Test were used. Ultimate pH and Hunter L were measured on the 10th-rib face 24 h postmortem. A section of bone-in loin containing the 10th rib was taken to the Iowa State University Meats Laboratory. At 48 h postmortem, Hunter L, CIE L*, a*, and b*, Japanese color score, and water-holding capacity were measured on the face of the 10th-rib loin chop. A slice from the 10th-rib loin section was evaluated for percentage of i.m. fat. The resulting loin chop was used for the determination of soluble myoglobin concentration (mg/g, wet basis). Chester White, Hampshire, and Duroc pigs had the highest (P < 0.05) myoglobin concentration (0.92, 0.95, and 0.85 mg/g, respectively), whereas Landrace had the lowest (0.62 mg/g; P < 0.05). No gender differences were detected for myoglobin concentration. The heritability estimate for soluble myoglobin concentration was 0.27. Residual correlations between soluble myoglobin and CIE L*, a*, b*, Hunter L (24 h), Hunter L (48 h), and Japanese color score were -0.17, 0.23, -0.15, -0.16, -0.13, and 0.13, respectively. These correlations are low but in the desired direction. The residual correlation between soluble myoglobin and intramuscular fat percent was 0.18. Results show that myoglobin concentration has a moderate heritability and could be used in a selection program to make pork loins darker in color.

Adipose Tissue↗

Design and standards for genetic evaluation of swine seedstock populations.

The purpose of this article is to describe a program for evaluation of seedstock populations in the swine industry. Differences among seedstock populations for economically important traits must be identified in order for pork producers to efficiently use available genetic resources. National genetic evaluation programs have the potential to identify the important differences among populations and to increase the rate of genetic improvement in a population. Program results provide performance benchmarks that stimulate testing and selection procedures by seedstock suppliers that further increase the rate of genetic improvement. A Terminal Sire Line Genetic Evaluation Program was designed and conducted in the United States by the National Pork Producers Council (Des Moines, IA) to compare seedstock populations for use in crossbreeding systems. High levels of statistical accuracy for program results were established; the ability to detect differences of 0.25 SD per trait, a power of test of 75%, and a 5% significance level were selected. Pure breeds and breeding company sire lines were nominated for the program. Semen was collected from nominated boars and distributed to cooperating commercial producers during eight 1-wk breeding periods. Pigs were produced in 136 commercial herds and transported to testing facilities at 8 to 23 d of age. Nine of the 11 sire lines originally entered in the program completed the sampling requirements for statistical analysis. High levels of statistical accuracy and a large, representative sample of boars with restrictions on genetic relationships ensured that the program results included unbiased, highly accurate sire line data for growth, carcass, meat quality, and eating quality traits of economic importance. This program has shown commercial producers that they have several choices of sire lines for changing their crossbreeding programs in desired trait areas. Commercial product evaluation must be an ongoing process, and this program serves as a model for future testing and evaluation of diverse genetic seedstock populations.

Animals↗

A comparison of hydrogen ion concentration and pH genetic predictions and fixed effect estimations when assessing pork quality.

An evaluation of ultimate pH (pH) and hydrogen ion concentration (H+) was conducted to determine if the mathematical conversion of H+ to pH could affect 1. fixed and random effect inferences and 2. prediction of genetic merit of animals when either pH or H+ is used as an indicator in the assessment of pork quality. Data from 4,262 purebred animals and 577 sires having complete three-generation pedigrees from the 1991 to 2001 National Barrow Show Progeny Tests were utilized in this study. Existing loin muscle pH data were converted to their original H+. Numerical changes in values occurred across all fixed effects and in the case of breed and test, changes in differences among subclasses occurred. These changes may result in differing inferences that can be made depending on whether pH or H+ is used as the dependent variable. Heritability estimates for pH and H+ were 0.52 +/- 0.074 and 0.62 +/- 0.078, respectively. The Pearson correlation between pH and H+ breeding values was -0.92. Spearman Rank correlation of -0.91 between pH and H+ breeding values was calculated and indicates that sires do not rank the same when ordered by breeding values for each trait. When pH is the selection objective, the selection differential reduction in H+ from these data ranges from 3.8 to 9.1%. Additionally, only 77.7% of the estimated genetic progress per generation in H+ is realized when selection (5% selected) is based on pH. The genetic correlation between pH and H+ was -0.96. Changes in the absolute values of the genetic correlations between various pork quality indicator traits and pH or H+ concentration were 0.04 or less. Differences in pH and H+ results could impact decisions made by swine breeders and meat processors who are concerned about pork quality. This, combined with the greater heritability and biochemical reality for H+, indicates that H+ rather than pH is the more appropriate trait breeders and processors should focus on when attempting to improve pork quality.

Animals↗

Genetic parameters for pork carcass components.

Data from 456 homozygous halothane normal purebred Yorkshire, Duroc, and Other-breed pigs from two national progeny testing and genetic evaluation programs were utilized to estimate genetic parameters for carcass components in pigs. Carcass components were cut and weighed according to Institutional Meat Purchase Specifications. Primal cut weights evaluated included 401 Ham (HAM), 410 Loin (LOIN), 405 Picnic shoulder (PIC), 406 Boston Butt (BB), and 409 Belly (BELLY). Individual muscle weights included the inside (INS), outside (OUT), and knuckle (KNU) muscles of the ham, the longissimus dorsi (LD) and psoas major (TEND) of the loin, and the boneless components of both the Boston Butt (BBUTT) and picnic (BPIC). Muscle weights from each primal were summed to yield a boneless subprimal weight (BHAM, BLOIN, BSHLDR), and all boneless subprimals were summed to yield total primal boneless lean (LEAN). Heritability estimates for HAM, LOIN, and BELLY were 0.57, 0.51, and 0.51, respectively. Heritability estimates for BB and PIC were 0.09 and 0.21, respectively. Heritability estimates for the boneless components of each primal were higher than those for the intact primals. Genetic correlations for HAM, LOIN, and PIC with loin muscle area (LMA) were 0.53, 0.78, and 0.70, respectively, and-0.62, -0.51, and -0.60, respectively, with 10th rib off-midline backfat (BF10). Boneless subprimal components were highly correlated with LEAN. Gilts had heavier weights (P < 0.01) than barrows for all boneless subprimals, individual muscles, LEAN, and for all primal cuts except BELLY. Gilts also had less BF10 and more LMA (P < 0.01) than barrows. Duroc pigs had a heavier (P < 0.01) weight for HAM and PIC when compared to Yorkshires. Yorkshire pigs had more (P < 0.01) LOIN weight than did the Durocs. Results suggest primal, boneless subprimal, and individual muscle weights in pigs should respond favorably to selection.

Adipose Tissue↗

Effect of gilt development diet on the reproductive performance of primiparous sows.

The objective of this study was to evaluate the effect of development diet on first-parity reproductive performance across different genetic types of females. Gilts (n = 708) 8 to 15 d of age from five genetic lines were assembled using a segregated early weaning protocol. Genetic types represented industry variation for reproductive capacity and lean growth potential. Sampling procedures were not designed to evaluate performance differences among the genetic lines. When the gilts weighed approximately 20 kg, they were moved from the nursery facilities to a slotted-floor, environmentally controlled facility, and seven to eight animals within a genetic type were penned together. When the gilts weighed approximately 40 kg, they were moved to a modified open-front facility. Nineteen gilts were allotted to each pen (.92 m2 per pig). Gilts were assigned to one of three development diets at 120 d of age. Diet 1 (high energy, 18% CP) and Diet 2 (high energy, 13% CP) were provided for ad libitum consumption to the assigned gilts until they weighed approximately 113 kg. Gilts receiving Diet 3 (23% CP) were fed 1.8 kg/d from 82 kg until they reached 180 d of age (approximately 100 kg). Gilts were fed 2 kg daily of a gestation diet from 180 d to 200 d of age and 2.7 kg daily from 200 d until mating. To stimulate the estrus cycle, gilts were commingled and exposed to vasectomized boars beginning at 180 d of age. Gilts that were in estrus and 210 d of age or older were artificially inseminated with commercial semen. Gilts not detected in estrus within the first 50 d of observation were injected with PG600 and estrus detection continued for 30 additional days. Of the 657 gilts entering breeding pens, 422 farrowed. Bred gilts were distributed to 10 cooperator facilities before farrowing. Mixed model procedures were used to analyze the data. Significant (P < .05) genetic type x gilt development diet interactions were found for number of pigs born, number of pigs born alive, total litter birth weight, and litter birth weight of pigs born alive. Significant interactions consistently involved one genetic line and gilt development Diets 1 and 2. Gilts from this genetic line-diet subclass had poorer farrowing performance (P < .05) than gilts from the same line fed development Diet 3. Only two other significant genetic line x gilt development diet interactions were found. Gilt development diet had little influence on first-parity reproductive performance.

Animal Feed↗

Development of adjustment factors for backfat and loin muscle area from serial real-time ultrasonic measurements on purebred lines of swine.

We recorded serial real-time ultrasonic measurements of backfat and loin muscle area to assess the rate of change per unit of live weight and growth rate measured as the change in weight per day of age during the finishing stage of production. Barrows (648) and gilts (459) representing eight major U.S. pure breeds of swine were evaluated in the study. Real-time ultrasonic measurements of backfat and loin muscle area were collected at average live weights (LW) of 67.4, 80.3, 93.4, and 104.9 kg. Backfat was measured at the midline over the last rib (LR) and last lumbar vertebra (LL) and off the midline at the 3/4 point (BF10) over the 10th rib. Loin muscle area (LMA) images were collected from the right-hand side of each pig at the 10th rib. Deposition rates were calculated on an intrapig basis for the dependent scan variables BF10, LMA, LR, and LL in models that included the independent variables LW and LW2. For growth rate (WDA), LW was regressed on age and age. Intrapig linear regression coefficients and y-intercepts were further analyzed as dependent variables in a mixed model that included the fixed effects test group, sex, and breed and random effects of sire and dam nested within breed. Significant breed effects were present for deposition rates of BF10, LMA, LR, LL, and WDA. Across the eight breeds, BF10 was deposited at a mean of .271 +/- .008 mm/kg, a rate faster than the average for LR (.201 mm/kg) and LL (.206 mm/kg). The LMA deposition rate across breeds averaged .304 cm2/kg. Average WDA across the breeds was .774 kg. Barrows deposited fat faster at all locations, deposited muscle slower, and grew faster than gilts in this study (P < .001). The results of this study indicate a need for breed- and sex-specific adjustment factors for rates of backfat and loin muscle deposition and for weight per day of age in swine.

Adipose Tissue↗