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- Eriksson, Susanne, et al.
(författare)
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Different beef breed sires used for crossbreeding with Swedish dairy cows - effects on calving performance and carcass traits
- 2020
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Ingår i: Livestock Science. - : Elsevier BV. - 1871-1413 .- 1878-0490. ; 232
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Tidskriftsartikel (refereegranskat)abstract
- Improved potential for weight gain and carcass classification traits in calves aimed at slaughter from dairy herds would increase the calves' economic value, and enable an increased beef production. At present, relatively low economic weights are placed on beef traits in the comprehensive Nordic dairy cattle breeding goal. An effective way to improve beef production from dairy herds is therefore to inseminate a larger proportion of dairy heifers and cows with beef bull semen. In the choice of beef bull breed, both effects on calving traits, carcass weight gain and carcass traits need to be considered. The aim of this study was therefore to compare different beef x dairy crosses regarding calving performance and carcass traits. Field data comprising in total close to 1.6 million calving records from Swedish herds, and more than 1.1 million carcass records from commercial slaughter houses, were analyzed using linear models. Differences in least-square means between different breed combinations were estimated for percentage of calving difficulty, stillbirth, daily carcass gain, carcass weight, EUROP conformation and fat classification. The dams were purebred Swedish Red (SR) or Swedish Holstein (SH), and the sires were either of purebred dairy (SR or SH) or of the beef breeds Angus, Hereford, Limousin, Simmental or Charolais. The results showed that crossbreeding dairy cows with beef bulls, especially of late maturing breeds, has potential to considerably improve beef production from dairy herds. Improvement of carcass characteristics and carcass gain were most noticeable in young crossbred bulls, where the highest increase for single breed combinations was 67% for conformation and 17% for carcass gain. Offspring of different beef x dairy combinations displayed varying average carcass gain and characteristics in terms of fatness and conformation in heifers, steers and young bulls, and would fit different types of production systems. Whereas crossbreeding had small or favorable effects on stillbirth, the use of late maturing beef breed sires negatively influenced the calving performance, especially in primiparous dairy cows. By choosing individual beef bulls with high estimated breeding values for calving ease, the percentage of calving difficulty could be reduced, even when using late maturing beef breed sires for crossbreeding.
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- Silvera, Anna, et al.
(författare)
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Modification of the human-broiler relationship and its potential effects on production
- 2016
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Ingår i: Acta Agriculturae Scandinavica, Section A - Animal Science. - : Informa UK Limited. - 0906-4702 .- 1651-1972. ; 66, s. 161-167
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Tidskriftsartikel (refereegranskat)abstract
- The present study was designed to investigate the effects of additional human contact (AHC) on the human-animal relationship (HAR) in broilers and on the birds' productivity. A total of 1558 broiler one-day-old chicks were distributed into 12 equally sized pens at two different stocking densities (SDs), calculated on estimated weight at slaughter (4 pens with 32kg/m(2) and 8 pens with 16kg/m(2)). Six groups (2 high and 4 low SDs) received AHC, which consisted of 30-min sessions with visual human contact three days/week. The remaining six groups received as little human contact as possible and served as controls. A touch test was used to assess the human-broiler relationship and the production parameters measured were growth rate, mortality, feed consumption and feed conversion. The AHC treatment had a positive effect on the quality of the HAR but failed to affect any production parameter.
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- Ahlman, Therese, et al.
(författare)
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Differences in preferences for breeding traits between organic and conventional dairy producers in Sweden
- 2014
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Ingår i: Livestock Science. - : Elsevier BV. - 1871-1413 .- 1878-0490. ; 162, s. 5-14
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Tidskriftsartikel (refereegranskat)abstract
- Development of sustainable breeding goals for dairy production has to consider the producers' preferences which are likely to differ between production systems. The number of dairy producers with herds certified according to the standards of organic production has increased during the last decades. Traditionally, organic producers use animals selected in conventional production systems but the traits important in organic herds have been suggested to differ due to the different production conditions. The aim of this study was to assess what traits Swedish organic and conventional daily producers consider to be important for the cows in their herds, and the relative importance of traits in the two production systems.An advanced web questionnaire with an underlying selection index was developed. The selection index was not shown to the respondents but it enabled them to weight traits against each other based on the genetic progress obtained. The questionnaire also included questions about what traits the producers intuitively considered important for the cows in their herds and how they ranked 15 given production and functional traits. The questionnaire was answered by 468 Swedish dairy producers of which 122 had a certified organic herd and 346 had a conventional herd.The results of this study show that the trait longevity was ranked first by both organic and conventional Swedish dairy producers. However, the ranking differed to some extent between the production systems for other traits, e.g. mastitis resistance and milk production. Swedish producers with organic herds tended to desire a higher genetic gain in disease resistance, including mastitis and parasite resistance, compared with producers with conventional herds. The results also reflect a somewhat lower interest in milk production level among producers with organic production. However, as the traits most important for Swedish producers with organic herds are already considered in the current Nordic breeding goal they can continue the use of this animal material. (C) 2014 The Authors. Published by Elsevier B.V.
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