Identification of quantitative trait loci affecting carcass composition in swine: II. Muscling and wholesale product yield traits

A genomic scan was conducted on 540 reciprocal backcross Meishan x White composite pigs for hot carcass weight (HCWT); loin eye area (LOIN); carcass length (CRCL); belly weight (BELLY); and weight of trimmed ham, loin, picnic, and Boston butt adjusted to a constant live (TWPLWT) or carcass (TWPCWT) weight. Genetic markers spanned the entire porcine linkage map and were spaced at approximately 20-cM intervals. Grandparental breed of origin for all chromosomal segments was determined using multipoint linkage procedures, and a least squares regression analysis was conducted. Nominal P-values were converted to a genome-wide level of significance to adjust for the number of tests actually conducted. Seven associations were significant at the genome-wide level relating to chromosomes 1 (SSC 1), 7 (SSC 7), and X (SSC X). The SSC 1 region affected LOIN, TWPLWT, and TWPCWT; SSC 7 affected HWCT and CRCL; and SSC X affected TWPLWT and TWPCWT. Twelve associations relating to seven chromosomal regions (including SSC 1 and X) presented suggestive evidence for quantitative trait loci (QTL), and many of these regions are likely to contain QTL. Chromosomes 8 and 14 had two and three traits with suggestive evidence for QTL, respectively. Many pleiotropic effects were detected for regions on SSC 1, 7, 14, and X in this study and a companion study looking for fat deposition QTL in the same population. In addition, SSC 4 was nearly significant for CRCL in the same region identified as affecting backfat in a wild boar x Large White population. These results expand our knowledge of the inheritance of quantitative traits and are directly relevant to composite populations containing Meishan germplasm.     

Heterogeneity of variances for carcass traits by percentage Brahman inheritance

Heterogeneity of carcass trait variances due to level of Brahman inheritance was investigated using records from straightbred and crossbred steers produced from 1970 to 1988 (n = 1,530). Angus, Brahman, Charolais, and Hereford sires were mated to straightbred and crossbred cows to produce straightbred, F1, back-cross, three-breed cross, and two-, three-, and four-breed rotational crossbred steers in four non-overlapping generations. At weaning (mean age = 220 d), steers were randomly assigned within breed group directly to the feedlot for 200 d, or to a backgrounding and stocker phase before feeding. Stocker steers were fed from 70 to 100 d in generations 1 and 2 and from 60 to 120 d in generations 3 and 4. Carcass traits included hot carcass weight, subcutaneous fat thickness and longissimus muscle area at the 12-13th rib interface, carcass weight-adjusted longissimus muscle area, USDA yield grade, estimated total lean yield, marbling score, and Warner-Bratzler shear force. Steers were classified as either high Brahman (50 to 100% Brahman), moderate Brahman (25 to 49% Brahman), or low Brahman (0 to 24% Brahman) inheritance. Two types of animal models were fit with regard to level of Brahman inheritance. One model assumed similar variances between pairs of Brahman inheritance groups, and the second model assumed different variances between pairs of Brahman inheritance groups. Fixed sources of variation in both models included direct and maternal additive and nonadditive breed effects, year of birth, and slaughter age. Variances were estimated using derivative free REML procedures. Likelihood ratio tests were used to compare models. The model accounting for heterogeneous variances had a greater likelihood (P < .001) than the model assuming homogeneous variances for hot carcass weight, longissimus muscle area, weight-adjusted longissimus muscle area, total lean yield, and Warner-Bratzler shear force, indicating improved fit with percentage Brahman inheritance considered as a source of heterogeneity of variance. Genetic covariances estimated from the model accounting for heterogeneous variances resulted in genetic correlations of or near unity. These results suggest that different genetic values be considered for genetic evaluation of carcass yield and shear force traits from steers with different degrees of Brahman inheritance.     

Prediction of slaughter cow composition using live animal and carcass traits

Slaughter cows (n = 120), representing four genotypes (British, continental, Bos indicus, and dairy) and three body condition classes (thin, moderate, and fat), n = 10 per subclass, were used to identify practical and accurate prediction equations for the yield of boneless manufacturing beef of specific fat percentages. Cows and their carcasses were weighed and evaluated for USDA yield and quality grade factors and for physical muscle and fat indicators. Carcass sides were fabricated; total fat percentage (TFP) was calculated as total fat (trimmed and chemical) divided by side weight, and tissue lean percentage (TLP) was calculated as boneless fat-free lean divided by soft tissue weight. Data were analyzed using maximum R2 multiple regression. The best live trait prediction model for TFP included live preliminary yield grade (LPYG), body condition score (LCOND), visual live muscle score (LMUSC), and live weight (LWT), R2 = .83. The best carcass trait TFP prediction model included adjusted preliminary yield grade (CPYGA); kidney, pelvic, and heart fat adjustment (CKPHADJ); marbling score (CMARB); and hot carcass weight (HCW), R2 = .92. The best live trait TLP prediction model included LPYG, LCOND, LMUSC, and LWT, R2 = .82. The best carcass trait TLP prediction model included CPYGA, CKPHADJ, CMARB, and lean maturity, R2 = .91. These data indicate that TFP and TLP of slaughter cows can be accurately and practically predicted using live animal and carcass traits.     

Trade-offs and individual differences in evolved traits.

Comments on Evolutionary psychology: Controversies, questions, prospects, and limitations (see record 2010-02208-001) by Confer et al. We applaud Confer et al.’s (February–March 2010) clarifications of the many misconceptions surrounding the use of evolutionary analyses in psychology. As they noted, such misunderstandings are common and result in a curious tendency of some of our colleagues to criticize evolutionary psychology without a firm understanding of evolution itself. Confer et al. also did an admirable job acknowledging current unresolved issues among evolutionary psychologists (e.g., the relative importance of group selection on humans). The above said, we disagree with their view that a current limitation of evolutionary psychology is its inability to explain phenomena “that appear to reduce an individual’s reproductive success, and cannot be explained by mismatches with, or hijacking of, our psychological mechanisms by modern-day novel inputs” (Confer et al., 2010, p. 122). Mismatches between modern environments and environments of evolutionary adaptedness are only one set of explanations for seemingly maladaptive traits (Nesse, 2005). Another set involves evolutionary trade-offs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age differences in self-perceptions of Type A traits.

Examined whether self-perceptions of Type A (coronary prone) behavior changed during adulthood in 211 Ss from 4 age groups (30–39, 40–49, 50–59, and 60–69 yrs) who completed a Type A scale derived from the Adjective Checklist. Ss were asked to provide both concurrent and retrospective self-assessments of Type A behaviors. It was found that age and self-rated Type A traits were not significantly related. However, changes in self-perceptions of Type A traits did appear to be age-related: Ss aged 30–39 yrs perceived themselves as becoming more Type A, while Ss aged 40+ yrs perceived themselves as becoming less Type A. This shift in Type A self-perception was most prominent in Ss aged 60+ yrs. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An evaluation of the differences in human evoked cortical potentials to visual stimuli

Saccharomyces cerevisiae nuclei possess a polyphosphatase activity which is insensitive to a number of inhibitors of ATPase and pyrophosphatase (PPase) activities of the same organelle. Heparin, an effective inhibitor of the nuclear polyphosphatase activity, does not alter either the ATPase and PPase activity. The nuclear polyphosphatase activity is optimal at pH 7.5. Bivalent metal cations stimulate this activity in the following order: Co2+ > Mg2+ > Zn2+ > Mn2+. However, the magnitude of the stimulating effect is much lower than that for the polyphosphatase activities from other organelles of the same yeast. The polyphosphatase activity is nearly the same for polyphosphates ranging from [symbol: see text] = 9 to [symbol: see text] = 208, but is 1.5 times higher for tripolyphosphate. The K(m) values for the hydrolysis of polyphosphates with chain lengths [symbol: see text] = 3, 15 and 208 are 100, 5 and 4.1 microM, respectively. The polyphosphatase activity differs in some properties from that of the cell envelope, cytosol and vacuoles of the same S. cerevisiae strain.     

Individual differences in reaction to meprobamate: A study in visual perception.

An investigation of the effect of meprobamate upon reactions to Necker Cube, Retinal Rivalry, Archimedes Spiral, and Peripheral Span on 68 college-age males, divided equally between drug and placebo conditions by the doubleblind method. No significant relationship appeared between the Maudsley Personality Inventory Extraversion scale and the test scores, nor between the tests themselves, with exception of cube and rivalry (r = + .35, p     

Age-related differences in three tests of visual imagery.

Adult age differences were explored on 3 short tests of ability to generate and manipulate mental images. Age-related decrements were found in all 3 tests and were especially marked on the Clock Test. The tests are all reliable, as shown by test–retest reliability coefficients. Correlations also revealed that the Brooks Letter Test and the East–West Test appear to tap one common underlying ability, whereas the Clock Test measured a somewhat different ability. The East–West and Clock tests, in particular, may provide rapid and easily administered assessment of age-related changes in aspects of mental imagery. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Individual differences in infant visual attention: recognition of degraded visual forms by four-month-olds

In 5 experiments, 4-month-old infants were tested for their ability to recognize degraded visual targets as a function of individual differences in fixation duration. Targets were degraded by removing 10% of the total contour either from vertices (vertex-absent) or from midsegments (vertex-present). Both qualitative and quantitative differences were found in long and short lookers' ability to recognize the degraded forms. Short-looking infants were able to recognize degraded forms in both vertex-absent and vertex-present conditions, but the vertex-absent discrimination was more difficult. Long-looking infants required longer familiarization times before showing evidence of recognition in the vertex-present condition, and were unable to recognize targets in which contour was removed at vertices. The findings are discussed within the framework of the persistence of early visual processing strategies, and reliance of long-looking infants on particular local elements in visual analysis.     

Age-related differences in visual search in dynamic displays.

The authors examined the ability of younger and older adults to detect changes in dynamic displays. Older and younger adults viewed displays containing numerous moving objects and were asked to respond when a new object was added to the display. Accuracy, response times, and eye movements were recorded. For both younger and older participants, the number of eye movements accounted for a large proportion of variance in transient detection performance. Participants who actively searched for the change performed significantly worse than did participants who employed a passive or covert scan strategy, indicating that passive scanning may be a beneficial strategy in certain dynamic environments. The cost of an active scan strategy was especially high for older participants in terms of both accuracy and response times. However, older adults who employed a passive or covert scan strategy showed greater improvement, relative to older active searchers, than did younger adults. These results highlight the importance of individual differences in scanning strategy in real-world dynamic, cluttered environments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of chromium picolinate on growth and serum and carcass traits of growing-finishing pigs

Three experiments were conducted to evaluate chromium picolinate (CrPic) in growing-finishing pigs. Treatments were replicated four times within each experiment with three pigs per replicate in Exp. 1 and four pigs per replicate in Exp. 2 and 3. Average initial weights were 37.8, 30.5, and 22.4 kg in Exp. 1, 2, and 3, respectively. In Exp. 1, the basal corn-soybean meal diet (B, 120% NRC Lys) was supplemented with 0, 25, 50, 100, or 200 ppb of Cr from CrPic. Daily gain was increased (Cr cubic, P < .02) and serum cholesterol decreased (Cr cubic, P < .08) by addition of CrPic. In Exp. 2, the basal diet was supplemented with 0, 100, 200, 400, or 800 ppb of Cr from CrPic. Daily gain and ADFI were decreased (Cr linear, P < .05) by CrPic. Serum cholesterol also was decreased (Cr quadratic, P < .05) by CrPic. Longissimus muscle area (LMA) and percentage of muscling (MUS) were increased (Cr quadratic, P < .01) and 10th rib fat (TRF) was decreased (Cr quadratic, P < .01) by CrPic. In Exp. 3, pigs were allotted to the following treatments: 1) B, 2) B + 1,467 ppb of picolinate (Pic), 3) B + 200 ppb of Cr from CrCl3.6H2O, 4) B + 1,467 ppb of Pic + 200 ppb of Cr from CrCl3.6H2O, 5) B + 100 ppb of Cr from CrPic, or 6) B + 200 ppb of Cr from CrPic. Longissimus muscle area and MUS were increased (P < .01) and TRF decreased (P < .01) in pigs fed CrPic but not in pigs fed CrCl3.6H2O and(or) Pic.(ABSTRACT TRUNCATED AT 250 WORDS)     

Developmental differences in catalase activity and hypoxic-hyperoxic effects on fluid balance in isolated lamb lungs

From these data, it seems highly likely that conservation of the involved tube does not substantially increase the risk of a future ectopic pregnancy, although it does slightly increase the chance of a subsequent intrauterine pregnancy. This advantage of conservative therapy is also demonstrable in patients with a repeat tubal pregnancy. Pregnancy rates after conservative operation still compare favorably with those after in vitro fertilization. There seems to be a slightly increased risk of persistent trophoblastic activity after laparoscopic conservative therapy compared with conservative surgical treatment by laparotomy, but prospective randomized data are lacking. The psychosocial and economic benefits of laparoscopic treatment are well established.     

Relationship of genetically transmitted alpha EEG traits to anxiety disorders and alcoholism

We tested the hypothesis that a heritable EEG trait, the low voltage alpha (LV), is associated with psychiatric disorders. Modest to moderate evidence for genetic linkage of both panic disorder and the low voltage alpha trait to the same region of chromosome 20q has recently been reported, raising the issue of whether there is a phenotypic correlation between these traits. A total of 124 subjects including 50 unrelated index subjects and 74 relatives were studied. Alpha EEG power was measured and EEG phenotypes were impressionistically classified. Subjects were psychiatrically interviewed using the SADS-L and blind-rated by RDC criteria. Alcoholics were four times more likely to be LV (including so-called borderline low voltage alpha) than were nonalcoholic, nonanxious subjects. Alcoholics with anxiety disorder are 10 times more likely to be LV. However, alcoholics without anxiety disorder were similar to nonalcoholics in alpha power. An anxiety disorder (panic disorder, phobia, or generalized anxiety) was found in 14/17 LV subjects as compared to 34/101 of the rest of the sample (P < 0.01). Support for these observations was found in the unrelated index subjects in whom no traits would be shared by familial clustering. Lower alpha power in anxiety disorders was not state-dependent, as indicated by the Spielberger Anxiety Scale. Familial covariance of alpha power was 0.25 (P < 0.01). These findings indicate there may be a shared factor underlying the transmissible low voltage alpha EEG variant and vulnerability to anxiety disorders with associated alcoholism. This factor is apparently not rare, because LV was found in approximately 10% of unrelated index subjects and 5% of subjects free of alcoholism and anxiety disorders.     

Preferred position of visual displays relative to the eyes: a field study of visual strain and individual differences

At office workplaces equipped with visual display units (VDU) that were adjustable to various positions relative to the eyes short and long viewing distances from the eyes to the screen were imposed (mean value of about 63 and 92 cm) at two levels of screen height so that the visual target was either at eye level or 18 cm below, on the average. The change from far to near viewing distance produced a larger increase in eyestrain when the VDUs were at eye level. High screens resulted in greater eyestrain than low screens, as shown by correlations over subjects. When operators were free to adjust the most comfortable screen position, the group of 22 participants preferred viewing distances between 60 and 100 cm and vertical inclination of gaze direction between horizontal and -16 degrees downwards. However, within most subjects the range of preferred screen positions was much smaller. Between 3 days during a 1-month period the test-retest correlations of the preferred screen positions were highly significant, both for viewing distance and vertical gaze inclination. When operators were forced to work at a shorter distance than their preferred viewing distance they reported more visual strain. Thus, operators appear to prefer an individual adjustment of the screen relative to the eyes in order to avoid visual strain and discomfort at VDU work.     

The emotional blink: Adult age differences in visual attention to emotional information.

To assess age differences in attention-emotion interactions, the authors asked young adults (ages 18-33 years) and older adults (ages 60-80 years) to identify target words in a rapid serial visual presentation (RSVP) task. The second of two target words was neutral or emotional in content (positive in Experiment 1, negative in Experiment 2). In general, the ability to identify targets from a word stream declined with age. Age differences specific to the attentional blink were greatly reduced when baseline detection accuracy was equated between groups. With regard to emotion effects, older adults showed enhanced identification of both positive and negative words relative to neutral words, whereas young adults showed enhanced identification of positive words and reduced identification of negative words. Together these findings suggest that the nature of attention-emotion interactions changes with age, but there was little support for a motivational shift consistent with emotional regulation goals at an early stage of cognitive processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Assessing the efficiency of multiplicative mixed model equations to account for heterogeneous variance across herds in carcass scan traits from beef cattle

Data (n = 2,658) from live animal ultrasonic measures from 17 Angus herds were used to evaluate a multiplicative mixed model that incorporates scaling factors to correct for across-herd heterogeneity of variance. Traits included were ribeye muscle area (EMA), surface fat at the P8 site (P8), surface fat between the 12th and 13th ribs (RIB12), and weight at scanning (WEIGHT). Cattle ranged in age from 501 to 698 d and represented 291 contemporary groups. Data were initially analyzed using single-trait, animal model, Method R procedures to estimate variance components and heritabilities (h2). These estimates were incorporated into a multiplicative mixed model that simultaneously estimates breeding values (EBV) and heterogeneity factors. Re-estimation of h2 after scaling the data with the correction factors was explored to obtain a measure of the improvement in the genetic evaluation and to detect changes in ranking of individuals and herds. Initial h2 estimates for EMA, P8, RIB12, and WEIGHT were .36, .39, .29, and .48, respectively. Scaling factors ranged from .25 for P8 in a herd with eight records to 1.96 for RIB12 in a herd with 86 individuals. Re-estimates of h2 increased by an average of 4.2% for all the traits as a result of correcting for heterogeneity. Deviations of new scaling factors were within expectations. Correlations between EBV with and without heterogeneity correction were greater than .97 for all the traits. However, some substantial re-rankings of herds were observed for some traits in the smaller herds.     

Age and visual field differences in computing visual-spatial relations.

Age and brain hemispheric differences in visual–spatial performance were investigated using 2 versions of categorical and coordinate (metric) spatial relations tasks. 32 young adults (M?=?19.2 yrs) and 32 older adults (M?=?68.8 yrs) participated. An overall age-related decrement in computing visual–spatial relations was obtained for lateralized presentations and when items were presented centrally. In contrast to some previous findings, there was no evidence to suggest differential aging of the right hemisphere in computing visual–spatial relations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Infant visual attention: Stability of individual differences from 6 to 8 months.

This study examined the stability of two aspects of infant visual attention derived from the paired-comparison procedure in infants tested at 6, 7, and 8 months: novelty preference and exposure time. Novelty preference, which reflects the relative amount of time the infants look at a new stimulus compared with a familiar stimulus, was found to be moderately stable, with cross-age correlations ranging from .30 to .50 when scores were averaged across six problems. Similar stability coefficients were found for counts of the number of problems for which infants exhibited novelty percentages exceeding an arbitrary criterion. Exposure-time scores, reflecting the time required to accumulate a preset amount of looking at the familiarization stimulus, also showed moderate stability, with cross-age correlations ranging from .32 to .38. These two measures of visual attention did not correlate well with one another and neither was related to contemporaneous measures of infant competence, represented by Bayley (1969) Mental Developmental Index (MDI) and Psychomotor Developmental Index (PDI) scores at 7 months. It was concluded that novelty and exposure-time scores each reflect moderately stable but independent characteristics of infant behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)