Data on weaning weight from 12,740 animals were used to compare different contemporary group (CG) definitions to be applied in the current genetic evaluation in the Avileña Negra Ibérica beef cattle breed. Several classical ‘ad-hoc’ statistics and criteria for statistical model comparison within a Bayesian analysis were used. Six alternative definitions for the CG effect were compared: Herdyear...

nomadic communities have always played a crucial role in meat production by developing creative and sustainable system in utilizing the scarce natural resources. during the last decade, fars’ nomads have been experiencing changes due to external pressures such as drought that have altered the social, political and economic landscapes and have also been the cause of decline in the health of rang...

A two-stage sampling approach is proposed for estimation of herd-level prevalence. Herd-level test characteristics are constructed based on individual animal test characteristics, herd size, sample size and within-herd level prevalences. The distribution of within herd prevalence is modeled using intracluster correlation coefficient. A herd-level sample size formula was developed which incorpor...

Resilient cows are minimally affected in their functioning by infections and other disturbances, recover quickly. Herd management is expected to have an effect on disturbances the resilience of cows, this was investigated study. Two indicators were first recorded individual cows. The herd-year these then estimated corrected for genetic year-season effects. 2 variance lag-1 autocorrelation daily...

Animal grouping behaviors have been widely studied due to their implications for understanding social intelligence, collective cognition, and potential applications in engineering, artificial intelligence, and robotics. An important biological aspect of these studies is discerning which selection pressures favor the evolution of grouping behavior. In the past decade, researchers have begun usin...

Analysing the effect of pastoral risk management strategies provides insights into a system of subsistence that have persevered in marginal areas for hundreds to thousands of years and may shed light into the future of around 200 million households in the face of climate change. This study investigated the efficiency of herd accumulation as a buffer strategy by analysing changes in livestock ho...