108 research outputs found
Genetic parameters for milk somatic cell score and relationships with production traits in primiparous dairy sheep
A total of 13,066 first-lactation test-day records of 2,277 Valle del Belice ewes from 17 flocks were used to estimate genetic parameters for somatic cell scores (SCS) and milk production traits, using a repeatability test-day animal model. Heritability estimates were low
and ranged from 0.09 to 0.14 for milk, fat, and protein yields, and contents. For SCS, the heritability of 0.14 was relatively high. The repeatabilities were moderate and ranged from 0.29 to 0.47 for milk production traits. The repeatability for SCS was 0.36. Flock-test-day explained a large proportion of the variation for milk production traits, but it did not have a big effect on SCS. The genetic correlations of fat and protein yields with fat and protein percentages were positive and high,indicating a strong association between these traits. The genetic correlations of milk production traits with SCS were positive and ranged from 0.16 to 0.31. The results showed that SCS is a heritable trait in Valle del Belice sheep and that single-trait selection for increased milk production will also increase SCS
Genetic and nongenetic variation of heifer fertility in Italian Holstein cattle
Excellent fertility performance is important to maximize farmers’ profit and to reduce the number of culled animals. Although female fertility of adult cows has been included in Italian Holstein breeding objectives since 2009, little has been done to quantify genetic variation of heifer fertility characteristics so far. The aim of the present study was to estimate genetic parameters of 4 fertility traits in nulliparous Italian Holstein heifers and to develop an aggregate selection index to improve heifer fertility. Data were retrieved from the national fertility database and included information on insemination, calving, and pregnancy diagnosis dates. The investigated phenotypes (mean ± standard deviation) were age at first insemination (AFI, mo; 17.25 ± 2.89), nonreturn rate at 56 d from the first insemination (NRR56, binary; 0.78 ± 0.41), conception rate at first insemination (CR, binary; 0.61 ± 0.49), and interval from first to last insemination (IFL, d; 26.09 ± 51.85). Genetic parameters were estimated using a 4-trait animal model that included the following fixed effects: herd-year of birth and month of birth for AFI, and herd-year-season of birth and month-year of insemination for IFL, NRR56, and CR; the animal additive genetic effect (fitted to the pedigree-based relationship matrix) was considered as a random term. An aggregate index was developed from the estimated additive genetic (co)variance matrix by considering CR as the breeding goal and AFI, NRR56, and IFL as selection criteria. Heritability estimates from average covariance matrices ranged from 0.012 (CR) to 0.015 (IFL), with the exception of AFI (0.071). Conception rate at first insemination was strongly correlated with both IFL (−0.730) and NRR56 (0.668), and weakly to AFI (−0.065), and the relative emphasis placed on each selection criteria in the aggregate index was 10%, 47%, and 43% for AFI, IFL, and NRR56, respectively. The results of the present study suggest that heifer fertility should be considered as an additional trait in the breeding objectives of Italian Holstein
Use of different statistical models to predict direct genomic values for productive and functional traits in Italian Holsteins
Risk Factors for Necrotizing Enterocolitis:A Prospective Multicenter Case-Control Study
BACKGROUND: The identification of independent clinical risk factors for necrotizing enterocolitis (NEC) may contribute to early selection of infants at risk, allowing for the development of targeted strategies aimed at the prevention of NEC. OBJECTIVE: The objective of this study was to identify independent risk factors contributing to the development of NEC in a large multicenter cohort. METHODS: This prospective cohort study was performed in 9 neonatal intensive care units. Infants born at a gestational age </=30 weeks were included. Demographic and clinical data were collected daily until day 28 postnatally. Factors predictive of the development of NEC were identified using univariate and multivariable analyses in a 1: 5 matched case-control cohort. RESULTS: In total, 843 infants (56 NEC cases) were included in this study. In the case-control cohort, univariate analysis identified sepsis prior to the onset of NEC and formula feeding to be associated with an increased risk of developing NEC, whereas the administration of antibiotics directly postpartum was inversely associated with NEC. In a multivariable logistic regression model, enteral feeding type and the number of days parenterally fed remained statistically significantly associated with NEC, whereas the administration of antibiotics directly after birth was associated with a lower risk of developing NEC. CONCLUSIONS: Formula feeding and prolonged (duration of) parenteral feeding were associated with an increased risk of NEC. Contrary to expectations, the initiation of treatment with antibiotics within 24 h after birth was inversely associated with NEC
The lived experience of discrimination by white women in committed interracial relationships with black men
Abstract: This study explores the experiences of discrimination by white women in committed interracial relationships with black men within the South African context from a descriptive phenomenological perspective. Three white females in committed interracial relationships with black males were recruited and interviewed. Open-ended interviews were conducted in order to elicit rich and in-depth first-person descriptions of the participants’ lived experiences of discrimination as a result of being in committed interracial relationships. The data analysis entailed a descriptive phenomenological content analysis and description. The results of this study suggest that white women in committed interracial relationships with black men experienced discrimination in various contexts where discrimination manifests as either a negative or a positive encounter; in addition, discrimination evokes various emotional responses and is coped with in either maladaptive or adaptive ways. Finally the experience of discrimination, although personal, necessarily impacts on the interracial relationship. Discrimination experienced by white women in committed interracial relationships with black men is thus multi-layered and both an intra-personal and inter-personal phenomenon
Understanding Face and Shame: A Servant-Leadership and Face Management Model
Clergy can have a negative impact on churches and other individuals when they knowingly or unknowingly attempt to save face, that is, try to protect their standing or reputation. The desire to gain face and the fear of losing face and feeling ashamed will likely permeate clergy’s decision-making processes without even being noticed. This study explores the essence of face and face management and the relationship between face management and two characteristics of servant-leadership—awareness and healing—in both Chinese and American churches through the methodology of hermeneutic phenomenology. Prior to this study, to my knowledge, no hermeneutic phenomenological research of face management has been conducted in a church setting. Through a review of the literature, four areas are explored: face and shame, face management, servant-leadership, and face, shame, and face management within the church. This study obtained approval from the Institutional Review Board and informed consent from the participants. Three Chinese and three American Christian ministers were chosen to complete a question sheet and participate in two semi-structured interview sessions. A first cycle of open coding and second cycle of pattern coding were used during data analysis. Face experiences are discussed in light of eight major themes: body, triggers, becoming, face concepts, strategies, emotions, servant-leadership, and the church. Findings from the study help build a servant-leadership and face management model, which can offer an anchored approach for clergy and pastoral counselors to address face and shame and to develop therapeutic interventions
Estimate of genetic parameters for carcass traits and visual scores inmeat sheep using Bayesian inference via threshold and linear models
Doxapram versus placebo in preterm newborns: a study protocol for an international double blinded multicentre randomized controlled trial (DOXA-trial)
Abstract
Background
Apnoea of prematurity (AOP) is one of the most common diagnoses among preterm infants. AOP often leads to hypoxemia and bradycardia which are associated with an increased risk of death or disability. In addition to caffeine therapy and non-invasive respiratory support, doxapram might be used to reduce hypoxemic episodes and the need for invasive mechanical ventilation in preterm infants, thereby possibly improving their long-term outcome. However, high-quality trials on doxapram are lacking. The DOXA-trial therefore aims to investigate the safety and efficacy of doxapram compared to placebo in reducing the composite outcome of death or severe disability at 18 to 24 months corrected age.
Methods
The DOXA-trial is a double blinded, multicentre, randomized, placebo-controlled trial conducted in the Netherlands, Belgium and Canada. A total of 396 preterm infants with a gestational age below 29 weeks, suffering from AOP unresponsive to non-invasive respiratory support and caffeine will be randomized to receive doxapram therapy or placebo. The primary outcome is death or severe disability, defined as cognitive delay, cerebral palsy, severe hearing loss, or bilateral blindness, at 18–24 months corrected age. Secondary outcomes are short-term neonatal morbidity, including duration of mechanical ventilation, bronchopulmonary dysplasia and necrotising enterocolitis, hospital mortality, adverse effects, pharmacokinetics and cost-effectiveness. Analysis will be on an intention-to-treat principle.
Discussion
Doxapram has the potential to improve neonatal outcomes by improving respiration, but the safety concerns need to be weighed against the potential risks of invasive mechanical ventilation. It is unknown if the use of doxapram improves the long-term outcome. This forms the clinical equipoise of the current trial. This international, multicentre trial will provide the needed high-quality evidence on the efficacy and safety of doxapram in the treatment of AOP in preterm infants.
Trial registration
ClinicalTrials.gov NCT04430790 and EUDRACT 2019-003666-41. Prospectively registered on respectively June and January 2020
QTL detection by multi-parent linkage mapping in oil palm (Elaeis guineensis Jacq.)
A quantitative trait locus (QTL) analysis designed for a multi-parent population was carried out and tested in oil palm (Elaeis guineensis Jacq.), which is a diploid cross-fertilising perennial species. A new extension of the MCQTL package was especially designed for crosses between heterozygous parents. The algorithm, which is now available for any allogamous species, was used to perform and compare two types of QTL search for small size families, within-family analysis and across-family analysis, using data from a 2 × 2 complete factorial mating experiment involving four parents from three selected gene pools. A consensus genetic map of the factorial design was produced using 251 microsatellite loci, the locus of the Sh major gene controlling fruit shell presence, and an AFLP marker of that gene. A set of 76 QTLs involved in 24 quantitative phenotypic traits was identified. A comparison of the QTL detection results showed that the across-family analysis proved to be efficient due to the interconnected families, but the family size issue is just partially solved. The identification of QTL markers for small progeny numbers and for marker-assisted selection strategies is discussed
Identification of quantitative trait loci for body temperature, body weight, breast yield, and digestibility in an advanced intercross line of chickens under heat stress
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