细化搜索
结果 1-2 的 2
Cost efficient biodiversity production in the pastoral landscape - estimation of cost functions
2005
Nilsson, F.(Swedish Univ. of Agricultural Sciences, Uppsala (Sweden))E-mail:Frederik.Nilsson@ekon.slu.se
Same public goods can only be produced jointly with private goods. This paper focuses on the biological diversity that could be produced on semi-natural pastures through the assistance of grazing animals. The question that is being investigated is what shapes the total and marginal cost functions for biological diversity production on semi-natural pastures have if private goods are already being produced using livestock at farms near the pastures. The empirical analysis shows that a quadratic function describes the costs well and that the production is characterized by increasing marginal costs.
显示更多 [+] 显示较少 [-]Effects of gender and HCG administration on skatole levels in liver and hepatic activities of cytochromes P4502E1 and P4502A6 in pigs
2005
Zamaratskaia, G.(Swedish Univ. of Agricultural Sciences, Uppsala (Sweden))E-mail:Galia.Zamaratskaia@lmv.slu.se | Chen, G.(Swedish Univ. of Agricultural Sciences, Uppsala (Sweden)) | Lundstroem, K.(Swedish Univ. of Agricultural Sciences, Uppsala (Sweden))
Accumulation of skatole levels in porcine fat tissue is a major reason for boar taint, an objectionable odour in meat from entire male pigs. In contrast to males, female pigs do not accumulate skatole in increased amounts. Hepatic metabolism is critical for the regulation of skatole. Cytochromes P4502E1 (CYP2E1) and P4502A6 (CYP2A6) are key enzymes involved in skatole metabolism. The objectives of this study were to evaluate the effects of gender and hCG stimulation on the activities of CYP2A6. Liver samples were taken at slaughter and analyzed for skatole concentrations, and for activities of CYP2E1 and CYP2A6. It was found that female pigs expressed higher CYP2E1 activity whereas activity of CYP2A6 did not differ between sexes. Skatole levels in the liver were higher in male pigs than in female pigs. Neither skatole levels nor enzyme activities were affected by hCG stimulation. It was concluded that the incidence of boar taint may depend on both the amount of skatole reaching the liver, and the activities of enzymes involved in skatole metabolism.
显示更多 [+] 显示较少 [-]