The effect of fast created inbreeding on litter size and body weights in mice

This study was designed to reveal any differences in effects of fast created versus total inbreeding on reproduction and body weights in mice. A line selected for large litter size for 124 generations (H) and a control line (K) maintained without selection for the same number of generations were crossed (HK) and used as a basis for the experiment. Within the HK cross, full sib, cousin or random mating were practised for two generations in order to create new inbreeding (IBF) at a fast rate. In the first generation of systematic mating, old inbreeding was regenerated in addition to creation of new inbreeding from the mating design giving total inbreeding (IBT). The number of pups born alive (NBA) and body weights of the animals were then analysed by a model including both IBT and IBF. The IBT of the dam was in the present study found to reduce the mean NBA with -0.48 (± 0.22) (p < 0.05) pups per 10% increase in the inbreeding coefficient, while the additional effect of IBF was -0.42 (± 0.27). For the trait NBA per female mated, the effect of IBT was estimated to be -0.45 (± 0.29) per 10% increase in the inbreeding coefficient and the effect of IBF was -0.90 (± 0.37) (p < 0.05) pups. In the present study, only small or non-significant effects of IBF of the dam could be found on sex-ratio and body weights at three and six weeks of age in a population already adjusted for IBT

Suckler cow efficiency – breed by environment interactions in commercial herds under various natural production conditions

Author's accepted version (postprint).This is an Accepted Manuscript of an article published by Taylor & Francis in Acta Agriculturae Scandinavia, Section A - Animal Science on 11 February 2020.Available online: 10.1080/09064702.2020.1717592The significance of breed by environment interaction on suckler cow efficiency traits was investigated, using production data from the Norwegian Beef Cattle Recording System and data collected (feed regimes, etc.) from 27 commercial suckler cow herds. Two statistical approaches were used; mean breed performance in extensive/intensive environments (mixed models), or as within breed regressions of cow performance on modelled cow energy intake. Aberdeen Angus produced higher weaning weight than Hereford below 12,000 MJ NE (241 kg) and Charolais below 13,000 MJ NE (244 kg) cow energy intake in the suckler period, after which the breeds re-ranked. The corresponding re-rank between Hereford and Charolais was at 14,500 MJ NE (263 kg) cow energy intake. Overall, breed by environment interactions were observed for calving interval, number/kg calves weaned/mated cow/year and energy efficiency, which emphasise that choice of cow breed should be dependent on the natural production resources available.acceptedVersio

Simulations of feed intake, production output, and economic result within extensive and intensive suckler cow beef production systems

Author's accepted version (postprint).This is an Accepted Manuscript of an article published by Elsevier in Livestock Science on 24/08/2020.Available online: https://www.sciencedirect.com/science/article/pii/S1871141320305758?via%3DihubacceptedVersio

Estimation of breed and heterosis effects for cow productivity, carcass traits and income in beef × beef and dairy × beef crosses in commercial suckler cow production

Author's accepted version (postprint).This is an Accepted Manuscript of an article published by Taylor & Francis in Acta Agriculturae Scandinavia, Section A - Animal Science on 1 April 2020.Available online: 10.1080/09064702.2020.1746825This study aims to investigate calving difficulties, birth-, weaning- and carcass weight, herd life of cow, age at slaughter, average daily carcass gain, carcass conformation, carcass fatness and carcass income per carcass, kg or day, in Aberdeen Angus (A), Hereford (H), Charolais (C), Limousin (L), Simmental (S), Norwegian red (N) and their crosses, in order to evaluate crossbreeding strategies. Direct and maternal breed additive and heterosis effects and predicted phenotypic means were estimated with multiple regression using SAS. Crosses with N resulted in higher weaning weight and less calving difficulties than beef purebreds. Due to favourable maternal additive effects of N on carcass weight and -income, crosses with British breeds had higher performance than the purebreds. (A × C) × C had overall high performance due to beneficial maternal heterosis effects on calving difficulties and carcass weight. In conclusion, utilising profitable heterosis effects have potential in commercial production, but are dependent on production systems.acceptedVersio

Inequalities in health: a comparative study between ethnic Norwegians and Pakistanis in Oslo, Norway

BACKGROUND: The objective of the study was to observe the inequality in health from the perspective of socio-economic factors in relation to ethnic Pakistanis and ethnic Norwegians in Oslo, Norway. METHOD: Data was collected by using an open and structured questionnaire, as a part of the Oslo Health Study 2000–2001. Accordingly 13581 ethnic Norwegians (45% of the eligible) participated as against 339 ethnic Pakistanis (38% of the eligible). RESULTS: The ethnic Pakistanis reported a higher prevalence of poor self-rated health 54.7% as opposed to 22.1% (p < 0.001) in ethnic Norwegians, 14% vs. 2.6% (p < 0.001) in diabetes, and 22.0% vs. 9.9% (p < 0.001) in psychological distress. The socio-economic conditions were inversely related to self- rated health, diabetes and distress for the ethnic Norwegians. However, this was surprisingly not the case for the ethnic Pakistanis. Odd ratios did not interfere with the occurrence of diabetes, even after adjusting all the markers of socio-economic status in the multivariate model, while self-reported health and distress showed moderate reduction in the risk estimation. CONCLUSION: There is a large diversity of self-rated health, prevalence of diabetes and distress among the ethnic Pakistanis and Norwegians. Socio-economic status may partly explain the observed inequalities in health. Uncontrolled variables like genetics, lifestyle factors and psychosocial factors related to migration such as social support, community participation, discrimination, and integration may have contributed to the observed phenomenon. This may underline the importance of a multidisciplinary approach in future studies

Improvement in the national genetic evaluation of warmblood riding horses by including information from related studbooks

acceptedVersio

Genetic conditions of joint Nordic genetic evaluations of lifetime competition performance in warmblood sport horses

acceptedVersio

The effect of fast created inbreeding on litter size and body weights in mice

This study was designed to reveal any differences in effects of fast created versus total inbreeding on reproduction and body weights in mice. A line selected for large litter size for 124 generations (H) and a control line (K) maintained without selection for the same number of generations were crossed (HK) and used as a basis for the experiment. Within the HK cross, full sib, cousin or random mating were practised for two generations in order to create new inbreeding (IB$_{\rm F})$ at a fast rate. In the first generation of systematic mating, old inbreeding was regenerated in addition to creation of new inbreeding from the mating design giving total inbreeding (IB$_{\rm T})$. The number of pups born alive (NBA) and body weights of the animals were then analysed by a model including both IB$_{\rm T}$ and IB$_{\rm F}$. The IB$_{\rm T}$ of the dam was in the present study found to reduce the mean NBA with –0.48 ($\pm$0.22) (p $<$ 0.05) pups per 10% increase in the inbreeding coefficient, while the additional effect of IB$_{\rm F}$ was –0.42 ($\pm$0.27). For the trait NBA per female mated, the effect of IB$_{\rm T}$ was estimated to be –0.45 ($\pm$0.29) per 10% increase in the inbreeding coefficient and the effect of IB$_{\rm F}$ was –0.90 ($\pm$ 0.37) (p $<$ 0.05) pups. In the present study, only small or non-significant effects of IB$_{\rm F}$ of the dam could be found on sex-ratio and body weights at three and six weeks of age in a population already adjusted for IB$_{\rm T}$

Suckler cow efficiency – breed by environment interactions in commercial herds under various natural production conditions

The significance of breed by environment interaction on suckler cow efficiency traits was investigated, using production data from the Norwegian Beef Cattle Recording System and data collected (feed regimes, etc.) from 27 commercial suckler cow herds. Two statistical approaches were used; mean breed performance in extensive/intensive environments (mixed models), or as within breed regressions of cow performance on modelled cow energy intake. Aberdeen Angus produced higher weaning weight than Hereford below 12,000 MJ NE (241 kg) and Charolais below 13,000 MJ NE (244 kg) cow energy intake in the suckler period, after which the breeds re-ranked. The corresponding re-rank between Hereford and Charolais was at 14,500 MJ NE (263 kg) cow energy intake. Overall, breed by environment interactions were observed for calving interval, number/kg calves weaned/mated cow/year and energy efficiency, which emphasise that choice of cow breed should be dependent on the natural production resources available