The estimated heritability of post-challenge survival in Group 1 was 0.42 ± 0.07 on the observed binary scale and 0.58 ± 0.09 on the underlying liability scale, derived from fitting a linear animal model and a sire-dam threshold model, respectively.
Variance components were analyzed using cross-sectional models, and moderate to high heritability was estimated for vibrio resistance in both the linear model (0.31 0.32) and the sire-dam threshold model (0.53) but not in the animal threshold model (0.006).
Given that the data sets could be appropriately analyzed (no parental phenotypes) with a sire-dam threshold model (SireDam), the SireDam and AnimB models yielded essentially identical results.
Therefore, for comparison purposes the data sets were analyzed using two animal threshold models (standard and new algorithm) and a sire-dam threshold model.
Instead, binary data are often modeled through sire or sire-dam threshold models, but, as stated above, this is not appropriate for all data structures, as parents with individual records may cause bias in estimating genetic parameters.
For an animal threshold model, the phenotypic variance is:, and the heritability is thus while for a sire-dam threshold model, the phenotypic variance is:, and the heritability is.
However, the problems associated with animal models were solved by employing the new algorithm to sample additive genetic variance (AnimB), resulting in essentially identical heritability estimates as an appropriate sire-dam threshold model (SireDam).
The two models presented are an animal threshold model using the new algorithm for sampling of additive genetic variance (AnimB) and a standard sire-dam threshold model (SireDam); posterior standard deviations are given in parentheses.
Our results enhance our understanding of the threshold of dam construction and may guide the management of dam construction on a regional landscape level.
A series of laser cleaning tests and cleaning assessment procedures were carried out to determine the damage threshold fluence (F dam) of the leather substrate and the ablation threshold fluence (F abl) of the soiling.
The integrated land use dynamics in the 14 concentric rings showed that the impact of dam construction extended to a threshold distance of 5000 6000 m from the dam site during the 1974 1988 period and to 2000 3000 m during the 1988–2004 period.
