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קהילה:
אסיף מאגר המחקר החקלאי
פותח על ידי קלירמאש פתרונות בע"מ -
Genetic analysis of dystocia and calf mortality in Israeli-Holsteins by threshold and linear models.
Year:
1988
Source of publication :
Journal of Dairy Science
Authors :
ולר, יהודה
;
.
Volume :
71
Co-Authors:
Weller, J.I., Department of Animal Sciences, University of Illinois, Urbana 61801.
Misztal, I., Department of Animal Sciences, University of Illinois, Urbana 61801.
Gianola, D., Department of Animal Sciences, University of Illinois, Urbana 61801.
Facilitators :
From page:
2491
To page:
2501
(
Total pages:
11
)
Abstract:
Calvings of 106,751 Israeli Holstein heifers were analyzed for dystocia and calf mortality, scored dichotomously, and a composite trait, scored trichotomously. Dystocia was also studied with 146,973 second and third parity records. Models fitted included herd-year-season, sex of calf, calving age, calving month, sire of cow, sire of calf, and groups of sire of cow and of calf. Herd-year-season, sire of cow and calf, and residuals were random with diagonal variance-covariance matrices. Herd-year-season variance was assume to be 10% of the residual component. Other variance components were estimated by REML for linear models and by the counterpart of REML for threshold models. Heritability estimates were two to five times greater in threshold than in linear models, but correlations between corresponding sire evaluations were all greater than .9. Linear model sire evaluations were skewed positively, whereas threshold model evaluations had symmetrical distributions. Heritability for dystocia was greater in first than in later parities. Correlations between first and later parity sire evaluations were less than .5. Thus, the genetic control of dystocia seems to be different for heifers and cows. Correlations between sire of cow and calf evaluations were less than .3. Correlations between dystocia and calf mortality evaluations were about .7.
Note:
Related Files :
Animal
animal disease
article
cattle
Dystocia
Female
Genetics
Models, Biological
mortality
pregnancy
עוד תגיות
תוכן קשור
More details
DOI :
Article number:
Affiliations:
Database:
סקופוס
Publication Type:
מאמר
;
.
Language:
אנגלית
Editors' remarks:
ID:
24693
Last updated date:
02/03/2022 17:27
Creation date:
17/04/2018 00:09
Scientific Publication
Genetic analysis of dystocia and calf mortality in Israeli-Holsteins by threshold and linear models.
71
Weller, J.I., Department of Animal Sciences, University of Illinois, Urbana 61801.
Misztal, I., Department of Animal Sciences, University of Illinois, Urbana 61801.
Gianola, D., Department of Animal Sciences, University of Illinois, Urbana 61801.
Genetic analysis of dystocia and calf mortality in Israeli-Holsteins by threshold and linear models.
Calvings of 106,751 Israeli Holstein heifers were analyzed for dystocia and calf mortality, scored dichotomously, and a composite trait, scored trichotomously. Dystocia was also studied with 146,973 second and third parity records. Models fitted included herd-year-season, sex of calf, calving age, calving month, sire of cow, sire of calf, and groups of sire of cow and of calf. Herd-year-season, sire of cow and calf, and residuals were random with diagonal variance-covariance matrices. Herd-year-season variance was assume to be 10% of the residual component. Other variance components were estimated by REML for linear models and by the counterpart of REML for threshold models. Heritability estimates were two to five times greater in threshold than in linear models, but correlations between corresponding sire evaluations were all greater than .9. Linear model sire evaluations were skewed positively, whereas threshold model evaluations had symmetrical distributions. Heritability for dystocia was greater in first than in later parities. Correlations between first and later parity sire evaluations were less than .5. Thus, the genetic control of dystocia seems to be different for heifers and cows. Correlations between sire of cow and calf evaluations were less than .3. Correlations between dystocia and calf mortality evaluations were about .7.
Scientific Publication
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