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1.
J Dairy Sci ; 105(4): 3282-3295, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35123777

ABSTRACT

In across-country genomic predictions for dairy cattle, 2 kinds of bull information can be used as dependent variables. The first is estimated breeding value (EBV) from the national genetic evaluations, assuming genetic correlations between countries are less than 1. The second is EBV from multitrait across-countries evaluation (MACE), assuming genetic correlations between countries equal 1. In the present study, the level of bias and reliability of a cross-countries genomic prediction using national EBV or MACE EBV as the dependent variable were investigated. Data from Brown Swiss Organizations joining the InterGenomics Service by Interbull Centre (Uppsala, Sweden) were used. National and MACE EBV of 3 traits (protein yield, cow conception rate, and calving interval) from 7, 5, and 4 countries, respectively, were used, resulting in 16 trait-country combinations. Genotypes for 45,473 SNP markers and deregressed (national or MACE) EBV of 7,490; 5,833; and 5,177 bulls were used in analysis of protein yield, cow conception rate, and calving interval, respectively. For most of trait-country combinations, the use of MACE EBV via single-trait approach resulted in less biased and more reliable across-countries genomic predictions. In case some of the MACE EBV might have been inflated, the resulting single-trait genomic predictions were inflated as well. For these specific cases, the use of national EBV via multitrait approach provided less bias and more reliable across-countries genomic predictions.


Subject(s)
Cattle/genetics , Genome , Genomics , Animals , Breeding , Female , Genomics/methods , Genotype , Male , Models, Genetic , Phenotype , Reproducibility of Results
2.
J Anim Sci ; 88(11): 3529-37, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20693414

ABSTRACT

The aim of this study was to find a simple measure for calf temperament discrimination, which can be useful as a selection criterion for on-farm French beef cattle breeding schemes. Behavioral records were registered at an average age of 5 and 7 mo, respectively, for 1,282 and 1,440 Limousin calves born in 24 French farms between August 2007 and April 2008. Measures were repeated for 810 calves at the 2 ages. The test procedure consisted of individually restraining the calves in a chute, then exposing them to a stationary human situated in front of the chute for 10 s. For every calf and each period of the test, the number of rush movements and the total number of movements were scored by visual appraisal using a continuous scale ranging from 0 (no movements) to 60 (continuous movements). Initial scores were also transformed to categorical scores and analyzed. Genetic correlation across ages were very high for all the traits (above 0.84 ± 0.20) suggesting that these traits are governed by the same pool of genes at the 2 ages. The corresponding phenotypic correlations were about 0.3 for all the measures. Heritabilities were moderate for all measures (from 0.11 to 0.31) with the total number of movements during weighing measured at 7 mo being the greatest. All the measures were highly correlated (from 0.73 ± 0.26 to 0.99 ± 0.02). Genetic correlation across sexes was not statistically different from 1. However, traits measured during weighing showed different genetic variance estimates for females and males. Similar results were obtained for the transformed categorical scores. According to these results, the total number of movements during weighing seems to be the most promising trait for on-farm genetic evaluation of French beef cattle temperament.


Subject(s)
Behavior, Animal/physiology , Cattle/genetics , Cattle/physiology , Temperament/physiology , Animal Husbandry , Animals , Breeding , Female , Genetic Variation , Male , Phenotype
3.
Animal ; 3(9): 1308-12, 2009 Sep.
Article in English | MEDLINE | ID: mdl-22444907

ABSTRACT

This study aimed at determining the effect of the increase of foraging opportunities on the behaviour and welfare of breeding mares housed in individual boxes but allowed outside 6 h a day in a bare paddock. One hundred Arab breeding mares were divided into two groups of 50 according to the treatment and allowed outside in two bare paddocks at the same density (115 mare/ha) where water and shelter were provided. The treatment consisted in providing the opportunity to forage on hay. Twenty-minute animal focal samplings and scan samplings were used to determine the time budget of the mares during the period from 0900 to 1500 h and study their social behaviour. A total of 300 focal sampling (6000 min), 3300 individual scan sampling (6000 min) and 62 group observations (1240 min) corresponding to the 100 mares were recorded. Non-parametric tests were used to analyse data. Results showed that experimental mares spent more time feeding (65.12% ± 2.40% v. 29.75% ± 2.45%, P < 0.01) and less time in locomotion (11.70% ± 1.31% v. 23.56% ± 1.34%, P < 0.01), stand resting (11.76% ± 2.57% v. 27.52% ± 2.62%, P < 0.01) and alert standing (5.23% ± 1.2% v. 14.71% ± 1.23%, P < 0.01). There was more bonding among experimental mares than control ones (26 v. 14, P < 0.05). Experimental mares showed more positive social interactions (P < 0.01) and less aggression (P < 0.01). These results suggest that giving densely housed mares foraging opportunities improves their welfare.

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