Our objective was to determine which of 2 split-time AI programs applied to suckled beef cows would result in greater pregnancy risk. Suckled beef cows (n = 1,062) at 12 locations in 4 states (CO, ...KS, MY, and WA) were enrolled. Cows were treated on d -7 with a progesterone insert concurrent with 100 µg GnRH and on d 0 with 25 mg PGF plus removal of the insert. Estrus-detection patches were affixed to cows at insert removal. The study was designed as a completely randomized experiment of 2 treatment combinations. Within location and balanced for parity (primiparous vs. multiparous), cows were assigned randomly to 2 treatment times (55 vs. 65 h after CIDR insert removal) at which time estrus-detection patches were assessed. Estrus was defined to have occurred when an estrus-detection patch was > 50% colored (activated). Cows determined to be in estrus were inseminated at either 55 or 65 h, whereas the residual nonestrous cows in both treatment times received GnRH at 55 or 65 h but were inseminated 20 h later at 75 or 85 h, respectively. Pregnancy outcomes were determined at 36 d after AI and at the end of the breeding season. Thus, pregnancy outcomes of interest were compared between the 55 + 75-h treatment combination and that of the 65+85-h combination. Expression of estrus was greater ( = 0.001) by 65 h after PGF than by 55 h (62.0% vs. 41.9%), respectively, and this proportion was influenced by parity (time x parity interaction; = 0.006). As a result, proportionally more ( < 0.001) cows received the timed AI at 75 than 85 h (59.4% vs. 40.6%). Similar proportions of cows not in estrus by 55 or 65 h were detected in estrus by 75 or 85 h (40.1% vs. 39.3%), respectively. The cumulative proportion of cows in estrus by 75 h was less ( < 0.001) than that by 85 h (66.7% vs. 76.7%), respectively. Pregnancy risks at 36 d differed among treatments, with cows detected in estrus and inseminated at 55 or 65 h having greater pregnancy risks than their time-inseminated herd mates at 75 or 85 h (62.3% vs.49.7%), respectively. Overall pregnancy risk for cows in the 65+85-h treatment combination was greater at 36 d than for cows in the 55 + 75-h treatment combination (61.0% vs. 51.4%), respectively. We conclude that the 65 + 85-h treatment combination produced more pregnancies than the 55 + 75-h combination, but its implementation may be somewhat less convenient in terms of cow handling times.
Despite a decline in explicit prejudice, adults and children from majority groups (e.g., White Americans) often express bias implicitly, as assessed by the Implicit Association Test. In contrast, ...minority-group (e.g., Black American) adults on average show no bias on the IAT. In the present research, representing the first empirical investigation of whether Black children's IAT performance parallels that of Black adults, we examined implicit bias in 7–11-year-old White and Black American children. Replicating previous findings with adults, whereas White children showed a robust ingroup bias, Black children showed no bias. Additionally, we investigated the role of valuing status in the development of implicit bias. For Black children, explicit preference for high status predicted implicit
outgroup bias: Black children who explicitly expressed high preference for rich (vs. poor) people showed an implicit preference for Whites comparable in magnitude to White children's ingroup bias. Implications for research on intergroup bias are discussed.
► We examined implicit intergroup bias in White and Black American children. ► White children showed an implicit ingroup bias, but Black children showed no bias. ► Explicit preference for high social status predicted implicit
outgroup bias for Black children. ► Attitudes toward social status may contribute to the development of implicit intergroup bias.
Comparisons of stocking rates across sites can be facilitated by calculating grazing pressure. We used peak standing crop and stocking rates from six studies in the North American Great Plains ...(Cheyenne, Wyoming; Cottonwood, South Dakota; Hays, Kansas; Nunn, Colorado; Streeter, North Dakota; and Woodward, Oklahoma) to calculate a grazing pressure index and develop relationships for harvest efficiency, utilization, grazing efficiency, and animal performance and production. Average grazing pressures for heavy, moderate, and light stocking across the study sites were 40, 24, and 14 animal unit days · Mg−1, respectively. These grazing pressures resulted in average harvest efficiency values of 38%, 24%, and 14% and grazing efficiencies of 61%, 49%, and 39% for heavy, moderate, and light stocking rates, respectively. Utilization increased quadratically as grazing pressure index increased, whereas grazing and harvest efficiencies exhibited a linear increase with grazing pressure. The latter indicates that nonlivestock forage losses (e.g., weathering, senescence, wildlife, insects) were disproportional across stocking rates. Average daily gain of livestock decreased linearly as grazing pressure index increased across study sites. Prediction equations reaffirm assumptions of 50% grazing efficiency and 25% harvest efficiency associated with moderate stocking. Novel here, however, is that harvest and grazing efficiencies increased at high grazing pressures and decreased at low grazing pressures. Use of grazing pressure index to “standardize” stocking rates across rangeland ecosystems in the North American Great Plains should improve communication among scientists, resource managers, and the public, and thus better achieve both production and conservation goals on these lands.
Reading disability (RD), or dyslexia, is a common heterogeneous syndrome with a large genetic component. Several studies have consistently found evidence for a quantitative-trait locus (QTL) within ...the 17 Mb (14.9 cM) that span D6S109 and D6S291 on chromosome 6p21.3-22. To characterize further linkage to the QTL, to define more accurately the location and the effect size, and to identify a peak of association, we performed Haseman-Elston and DeFries-Fulker linkage analyses, as well as transmission/disequilibrium, total-association, and variance-components analyses, on 11 quantitative reading and language phenotypes. One hundred four families with RD were genotyped with a new panel of 29 markers that spans 9 Mb of this region. Linkage results varied widely in degree of statistical significance for the different linkage tests, but multipoint analysis suggested a peak near D6S461. The average 6p QTL heritability for the 11 reading and language phenotypes was 0.27, with a maximum of 0.66 for orthographic choice. Consistent with the region of linkage described by these studies and others, there was a peak of transmission disequilibrium with a QTL centered at JA04 (χ2=9.48; empirical P=.0033; orthographic choice), and there was strong evidence for total association at this same marker (χ2=11.49; P=.0007; orthographic choice). Although the boundaries of the peak could not be precisely defined, the most likely location of the QTL is within a 4-Mb region surrounding JA04.
Reading disability (RD), or dyslexia, is the most common learning disability with a prevalence rate of ~5%-10% in school-age children. RD is highly heritable with evidence of a neurobiological ...origin. Linkage studies have identified several quantitative trait loci (QTLs) for RD. The QTL on chromosome 6p21.3 has been independently replicated by several groups and spans a 16.4-Mb (13.8 cM) interval from D6S109 to D6S291. In this study, we performed sib-pair linkage analyses with Haseman-Elston and DeFries-Fulker methods to define more accurately the QTL interval. Linkage was assessed by using five quantitative phenotypes, including a composite measure of reading performance and four component phenotypes. When probands were selected for severe scores, single- and multi-point analyses showed significant linkage with all five phenotypes, converging over an interval of ~3.24 Mb spanning D6S1597 to D6S1571. Maximal linkage converged at marker D6S1554 across phenotypes. Out of 12 genes in the linkage interval, ten clustered within ~680 kb and were selected for association analysis based on central nervous system expression and putative function. Marker-trait associations were assessed by using QTDT (a general test of association for quantitative traits) and the family-based association test (FBAT), and haplotype analysis was performed by using FBAT and the GeneHunter Transmission/Disequilibrium Test TDT. Marker associations were detected in five of the ten genes, results that were corroborated by our haplotype TDT analysis. The results of the association study have thereby allowed us to significantly reduce the number of possible candidate genes and to prioritize genes for further mutation screening.
Cougars (Puma concolor) have been recolonizing portions of their historic range over the last few decades and are currently a rare, transient species in the western Great Lakes Region. Anticipatory ...attitude surveys can identify potential management challenges, stakeholder groups, and conservation and educational priorities for recolonizing cougars. We implemented an anticipatory attitude survey to better understand attitudes towards transient cougars in northern Wisconsin, USA. We distributed the survey in fall and early winter of 2014–15 (n = 423) and 2015–16 (n = 594). We compared attitudes towards transient cougars to attitudes towards other established large carnivores and white-tailed deer (Odocoileus virginianus). We also explored factors that may affect human attitudes towards cougars, such as hunter identity, livestock ownership, risk perception, and the loss of a domestic animal to wildlife. Despite the rare, transient status of cougars in Wisconsin, many respondents (mean of 29%) reported to have observed a cougar or sign of one in the wild in Wisconsin. Cougars had a mean favorability score similar to coyotes (Canis latrans) and wolves (Canis lupus) and less than bobcats (Lynx rufus), bear (Ursus americanus), and white-tailed deer. Comparatively, respondents’ risk perception for all categories of risk (i.e., fear for personal safety, the safety of children, and the safety of domestic animals) was higher for cougars than for wolves. Hunter identity and loss of livestock to wildlife were determined by multinomial logistic regression as the most important parameters affecting respondents’ favorability towards cougars (ωi = 0.71). Using the 2015–2016 survey data, we found that as cougar risk perception increased, favorability towards cougars decreased similarly for both hunters and non-hunters. Hunters were less likely to be favorable towards cougars, more likely to be neutral, and equally likely to be unfavorable towards cougars compared to nonhunters. We identify potential management challenges, stakeholder groups (e.g., hunters and those who have experienced loss of livestock to wildlife), and conservation and educational priorities for recolonizing cougars.
Change in frequency and intensity of tillage practices alters the soil properties, distribution of nutrients, and soil organic matter in the soil profile. We hypothesized that 8 yr of no-till (NT), ...chisel plow (CP), and moldboard plow (MP) treatments would affect chemical properties and organic matter of eroded soil. The corn (Zea mays L.)-soybean Glycine max (L.) Merr. rotation study was established in tall fescue (Festuca arundinacea L.) sod on a previously eroded, moderately well-drained, Grantsburg (Fine-silty, mixed, mesic Oxyaquic Fragiudalf) soil in southern Illinois. In the eighth year, soil pH, exchangeable Ca, and Bray P-1 were greater in NT than in CP and MP in the 0- to 5-cm soil depth. In the 0- to 5-cm soil depth, exchangeable K and Mg were greater with the CP than with the NT and MP. In the 5- to 15-cm soil depth, exchangeable Ca and Mg were greater in the MP and CP than in NT, due to mixing. Soil pH and P were greater for CP than MP and NT in the 5- to 15-cm layer. Exchangeable K in the 5- to 15-cm soil depth was greater in the MP than CP and NT. In the 0- to 5-cm soil depth, NT, CP, and MP had 38, 35, and 31% of their total C as particulate organic matter (POM), respectively. After 8 yr, CP and MP had less total organic C than NT in the 0- to 5-cm depth. In the 0- to 5-cm depth, CP and MP had less POM C than NT. The greater reduction of organic C in the POM fraction than in whole soil showed that POM was the most tillage-sensitive fraction of organic matter. After 8 yr of study, the water-stable aggregates in the 0-to 5-cm soil depth of MP and CP was reduced compared with NT. The effects of tillage treatment and associated soil erosion either resulted in different findings from tillage treatments on uneroded soil or affected the trend and magnitude of the soil property differences between treatments. For the 10-yr period prior to the establishment of the tillage experiment the site was managed as hayland. At the end of 8 yr, the NT maintained or improved nutrient retention and aggregate stability in the 0- to 5-cm layer compared with MP and CP.
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