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71.
Ola Thomsson Ann-Sofi Bergqvist Ylva Sjunnesson Lena Eliasson-Selling Nils Lundeheim Ulf Magnusson 《Acta veterinaria Scandinavica》2015,57(1)
Background
Lactating sows in Swedish organic piglet production are commonly group-housed with piglets in a multi-suckling pen within 14 days after farrowing. Nursing behaviour may be disturbed when lactating sows are moved to a new environment and mixed with other sows, as they spend more time fighting with other sows and exploring the new surroundings. This can disrupt the inhibitory effect of suckling on ovarian activity and increase the risk of lactational oestrus, making efficient reproductive management difficult. Therefore this study evaluated aggression and levels of the stress hormone cortisol in lactating sows group-housed together with their piglets at one (W1), two (W2) or three (W3) weeks post farrowing.Results
There was no significant difference (P > 0.05) between the three management routines (W1, W2, W3) regarding number of attacks initiated or received in the mixed group. After mixing, W2 sows had a lower number of shoulder scratches (P < 0.05) than W3 sows. Among the W3 sows, there was a lower (P < 0.01) cortisol concentration in saliva when sows were group housed compared to when they were individually housed. The cortisol response, measured as variation in cortisol concentration in saliva, was also lower (P < 0.05) in group-housed W3 sows compared with W1 sows.For all management routines, sows already living in the new environment (resident sows) initiated more attacks (P < 0.001) and received fewer attacks (P < 0.01) than sows entering the new environment (intruder sows). Overall, multiparous sows initiated more attacks and received fewer attacks than primiparous sows (P <0.001).Conclusions
Overall, the results suggest that mixing and group housing sows at three weeks post farrowing is less stressful than mixing and group housing sows at one week post farrowing. The results also indicate that parity and whether a sow is a resident or intruder in the group housing environment may have an effect on aggression levels when sows are group-housed. 相似文献72.
. Viklund S. Furre S. Eriksson O. Vangen J. Philipsson 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2015,132(4):308-317
Breeding programmes for warmblood sport horses are similar in the Nordic countries Sweden, Denmark, Finland and Norway, and stallions of same origin are used. The aim was to investigate whether a joint Nordic genetic evaluation based on lifetime competition performance is feasible and beneficial for breeding competitive sport horses in the Nordic countries. Results for almost 45 000 horses in show jumping and 30 000 horses in dressage were available. The larger populations in Sweden and Denmark contributed with 85% of the results. Heritabilities and genetic correlations between performances in the different countries were estimated, and comparisons of accuracies of estimated breeding values (EBVs) and number of stallions with EBVs based on national or joint data were studied. The heritabilities ranged between 0.25 and 0.42 for show jumping and between 0.14 and 0.55 for dressage. The genetic correlations between competition performances in the Nordic countries were estimated to 0.63–1.00. EBVs based on joint data increased accuracies for EBVs for stallions by 38–81% and increased the number of available stallions with EBVs by 40–288%, compared to EBVs based on national data only. A joint Nordic genetic evaluation for sport horses is recommended. 相似文献
73.
J. Häggström A. Boswood M. O'Grady O. Jöns S. Smith S. Swift M. Borgarelli B. Gavaghan J.‐G. Kresken M. Patteson B. Åblad C.M. Bussadori T. Glaus A. Kovačević M. Rapp R.A. Santilli A. Tidholm A. Eriksson M.C. Belanger M. Deinert C.J.L. Little C. Kvart A. French M. Rønn‐Landbo G. Wess A. Eggertsdottir M. Lynne O'Sullivan M. Schneider C.W. Lombard J. Dukes‐McEwan R. Willis A. Louvet R. DiFruscia 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2013,27(6):1441-1451
74.
M. Eriksson L. Waldenstedt K. Elwinger B. Engström O. Fossum 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(2):112-124
Abstract Only fast-growing broilers are available for organic production in Sweden, and due to organic legislations and long rearing periods feed restriction has to be practised. To evaluate the effect on welfare aspects and health, two diets, low in crude protein content, with (LPA) and without amino acid supplements (LP) were fed to 1400 Ross 308 chickens, divided over eight pens in two chicken houses, with access to outdoor pasture. Behavioural observations were conducted at 2, 6 and 10 weeks. In general, birds fed the LP diet used their outdoor pasture more, and showed a higher frequency of behaviours related to feed search, than the LPA birds. The LPA diet resulted in higher live weight, mortality and more leg problems. However, cannibalism outbreaks which are rarely seen in broiler production occurred in the LP birds. This indicates that new problems were introduced that are not beneficial for animal welfare. Furthermore, the behaviour differences related to feed search, changes between behaviours and preening might have indicated a frustration related to the qualitative feed restriction for the chickens given the LP diet. 相似文献
75.
T. A. Skjerve L. Grøva L. K. Sørheim M. Slagboom S. Eriksson M. Kargo 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(3):117-123
ABSTRACTThe aims of this study were to investigate variation and clustering in breeding goal trait preferences among Norwegian dairy farmers and to identify factors with a systematic influence on their preferences. An internet-based questionnaire was sent out to dairy farmers connected to the Norwegian co-operative breeding organization Geno (N?=?8222), of which 10.8% answered (N?=?888). Of the 15 suggested traits fertility had the highest overall ranking, while parasite resistance and methane emission had the lowest. Four distinct preference clusters were identified by the means of cluster analysis, of which two had a high preference for milk production. Differences in terms of farm and herd characteristics between clusters suggests a mixture of systematic and intrinsic effects on breeding goal trait priorities. This study shows that Norwegian dairy farmers’ preferences for breeding goal traits fall into four distinct clusters, both affected by herd and farm characteristics along with intrinsic values. 相似文献
76.
M. Eriksson L. Waldenstedt B. Engström K. Elwinger 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(4):211-219
Abstract Organic feed legislation, long-rearing periods and high requirements of sulphur-rich amino acids (AAs) complicate the composition of a well-balanced organic diet for broilers. To evaluate the effect of protein and AA composition, three different diets were fed to 180 Ross broilers, divided over 45 pens. The diets comprised a low crude protein (CP) and AA diet, a high CP diet aiming at AA levels used in conventional production and a low protein diet supplemented with lysine, methionine and threonine up to levels of the high protein diet. Chickens were immunologically challenged with an inactivated infectious bursal disease (IBD) vaccine; antibody titres, heterophil/lymphocyte (H/L) ratios, lymphoid organ weights and digestibility coefficients were recorded. In general, bird performance improved with increasing dietary CP and AA levels. Dietary treatments did not significantly affect any of the measured immune or stress-related parameters. 相似文献
77.
The conversion of rice hulls into fermentable saccharides was explored through steam pretreatment employing 2.5% SO2. The interaction between temperature and time was assessed by means of the response surface method to achieve optimum contents of C6-sugars in water-insoluble solids (WIS) and C5-sugars in the liquor. Pretreatment carried out at 218 °C for 2.3 min released liquor containing 55.4 g/L of sugars (29.1 g/L of xylose). In parallel, the WIS was subjected to enzymatic saccharification using different solid and enzyme loads via an experimental design: assays using 22.0% WIS and 20.0 filter paper units (FPU)/g led to 90.6 g/L of glucose, corresponding to a yield of 86.4% and an overall yield of 72.4%. The data reported are the highest ever found for such raw material, making it attractive to compete with conventional lignocellulosic biomass. 相似文献
78.
79.
Hampus Eriksson Kim Friedman Moses Amos Ian Bertram Kalo Pakoa Rebecca Fisher Neil Andrew 《Fish and Fisheries》2018,19(2):308-320
Interacting social and ecological processes shape productivity and sustainability of island small‐scale fisheries (SSF). Understanding limits to productivity through historical catches help frame future expectations and management strategies, but SSF are dispersed and unaccounted, so long‐term standardized data are largely absent for such analyses. We analysed 40 years of trade statistics of a SSF product that enter international markets (sea cucumber) from 14 Pacific Island Countries and Territories (PICT) against response variables to test predictors of fishery production: (i) scale, (ii) productivity and (iii) socio‐economics. Combined production in PICT peaked over 20 years ago, driven by exploitation trends in Melanesia that accounted for 90% of all production since 1971. The size of island fisheries (as measured by total exports), and the duration and magnitude of fishery booms were most influenced by ungovernable environmental variables, in particular land area. The large and high islands of Melanesia sustained larger booms over longer periods than atoll nations. We hypothesize that land area is a proxy for land‐based nutrient availability and habitat diversity, and therefore the productivity of the shallow water areas where SSF are operating. PICT need to tailor management based on the intrinsic productivity of shallow inshore habitats: harvests from atoll nations will need to be smaller per unit area than at the high islands. Particularly countries with low productivity fisheries must consider the crucial economic “safety nets” that export SSF make up for dispersed island populations and incorporate them into broader development and island resilience strategies. 相似文献
80.
Daniel Eriksson Mehrdad Arshadi Rashmi Kataria Urban Bergsten 《Scandinavian Journal of Forest Research》2018,33(6):594-602
The objectives were to determine the content and composition of lipophilic extractives, particularly fatty and resin acids, in three Scots pine trees from each of two stands in northern Sweden, one that was due for thinning and one due for final cutting. Extractives content of branches, needles, barks, stem discs from branch whorls, and sapwood and heartwood samples from various heights was measured. Fractions had very different concentrations and distributions of extractives due to differences in the composition of tissues. The needles had the highest total extractive concentration (around 150?kg/ton d.w.), followed by the branches, bark, timber from the final cut stand, and then the pulpwood and timber from the thinning stand. The final cut stand generally provided higher yields of extractives in assortments per hectare than the thinning stand; the difference was five-fold for timber, three-fold for whole trees, two-fold for branches, needles and bark and similar for pulpwood. This information on the content and composition of extractives in different tissues, and the dependence of these quantities on tree age could be used together with information on conventional stand data such as tree numbers and dimensions to guide the selection and management of feedstocks for biorefineries. 相似文献