Parametric bootstrap for testing model fitting of threshold and grouped data models: an application to the analysis of calving ease of Bruna dels Pirineus beef cattle

A Cow-Calf Farming System Fully Adapted to Elevation and Harsh Conditions in Andorra (Europe)

The use of natural resources is an important topic to optimize the efficiency of cattle production. The purpose of this work is to describe the project of the Bruna d'Andorra; a local cow breed under an extensive cow-calf system in Andorra (Europe), as an example of local farming and marketing of its meat products in an area with adverse environmental conditions. This breed is located in Andorra, a microstate that consists predominantly of rugged mountains and harsh weather conditions. The cow-calf Bruna d'Andorra extensive system is thoroughly described and productive and reproductive performance, compiled over 21 years (2000-2020), has been analyzed by years with the Chi-square test or ANOVA to compare proportions or means, respectively, and regression analysis was used to decipher evolution across years. The results show a population with a census large and stable enough to avoid inbreeding. Moreover, a sustained improvement of the productive performance and maternal fitness has been observed along the studied period for Bruna d'Andorra. The work concludes that local breeds can achieve sustainable animal production, especially when farmers, public administration and commercial circuits in the area agree to cooperate on such projects. The study also concludes that the Bruna d'Andorra cow breed can still improve in meat and reproductive performance.

Psychological Empowerment and Work Engagement as Mediating Roles Between Trait Emotional Intelligence and Job Satisfaction

The majority of research indicates that trait emotional intelligence (EI) plays a crucial role in personal well being; however, the deeper mechanisms of this link remain unclear. The study explored the impact of psychological empowerment and work engagement in the link between trait EI and job satisfaction. Female nurses (370) completed the EI Scale, the Psychological Empowerment Scale, the Utrecht Work Engagement Scale, and the Brief Index of Affective Job Satisfaction. The results of structural equation modeling demonstrated that work engagement partially mediated the association between trait EI and job satisfaction. Moreover, the serial one mediator model revealed that trait EI could influence job satisfaction via the serial mediating impact of “psychological empowerment–work engagement.” These results help to a better understanding of the association between these variables and demonstrate that high trait EI may improve occupational well being from emotional perspectives.

The mediating effect of work–life balance on the relationship between work–family conflict and life satisfaction

The first purpose of this study was to develop a scale of work–life balance for Turkish working women and men. The second purpose was to investigate the mediating effect of work–life balance between work–family conflict, family–work conflict, and life satisfaction. In Study 1 ( N = 274), a work–life balance scale was developed and initial validity evidence was presented. In Study 2 ( N = 356), confirmatory factor analyses supported the scale’s unidimensionality. Cronbach’s alpha and the composite reliability for internal consistency were .92. All studies indicated that the Work–Life Balance Scale was valid and reliable for a Turkish employee sample. Structural equation modeling supported indirect effects of work–family conflict and family–work conflict on life satisfaction via work–life balance. Multi-group analysis showed that the structural paths of the full model did not differ by gender.

Carcass conformation and fat cover scores in beef cattle: a comparison of threshold linear models vs grouped data models

BACKGROUND

Beef carcass conformation and fat cover scores are measured by subjective grading performed by trained technicians. The discrete nature of these scores is taken into account in genetic evaluations using a threshold model, which assumes an underlying continuous distribution called liability that can be modelled by different methods.

METHODS

Five threshold models were compared in this study: three threshold linear models, one including slaughterhouse and sex effects, along with other systematic effects, with homogeneous thresholds and two extensions with heterogeneous thresholds that vary across slaughterhouses and across slaughterhouse and sex and a generalised linear model with reverse extreme value errors. For this last model, the underlying variable followed a Weibull distribution and was both a log-linear model and a grouped data model. The fifth model was an extension of grouped data models with score-dependent effects in order to allow for heterogeneous thresholds that vary across slaughterhouse and sex. Goodness-of-fit of these models was tested using the bootstrap methodology. Field data included 2,539 carcasses of the Bruna dels Pirineus beef cattle breed.

RESULTS

Differences in carcass conformation and fat cover scores among slaughterhouses could not be totally captured by a systematic slaughterhouse effect, as fitted in the threshold linear model with homogeneous thresholds, and different thresholds per slaughterhouse were estimated using a slaughterhouse-specific threshold model. This model fixed most of the deficiencies when stratification by slaughterhouse was done, but it still failed to correctly fit frequencies stratified by sex, especially for fat cover, as 5 of the 8 current percentages were not included within the bootstrap interval. This indicates that scoring varied with sex and a specific sex per slaughterhouse threshold linear model should be used in order to guarantee the goodness-of-fit of the genetic evaluation model. This was also observed in grouped data models that avoided fitting deficiencies when slaughterhouse and sex effects were score-dependent.

CONCLUSIONS

Both threshold linear models and grouped data models can guarantee the goodness-of-fit of the genetic evaluation for carcass conformation and fat cover, but our results highlight the need for specific thresholds by sex and slaughterhouse in order to avoid fitting deficiencies.