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KL Goularte EM Madeira CER Ferreira EH Duval AD Vieira RG Mondadori T Lucia Jr 《Reproduction in domestic animals》2015,50(6):972-979
Bull semen production centres (SPC) generally present satisfactory quality control for sperm processing, but non‐standardized hygiene procedures. This study describes a Hazard Analysis and Critical Control Points (HACCP) system developed for bull SPC and subsequently implemented in a commercial SPC. After the identification of hazards at each step of semen processing and the determination of their risk and severity, monitoring and corrective procedures were designed to assess the system's efficiency. The HACCP system identified six microbiological hazards, 10 physical hazards, four chemical hazards and three critical control points. After the establishment of Good Processing Practices, Standard Operating Procedures and Standard Sanitizing Operating Procedures, the system was validated through an audit, to identify eventual failures and to define measures to correct them. 相似文献
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Estimating the non-market costs and benefits of native woodland restoration using the contingent valuation method 总被引:1,自引:0,他引:1
The restoration of native forests is an important priority forforestry and conservation organizations in the United Kingdom.The economic case for public sector support for native woodlandrestoration in the United Kingdom rests almost entirely on theprovision of non-market benefits related to wildlife, landscapeand recreational opportunities. This paper describes a discretechoice contingent valuation (CV) to estimate the value of thenon-market benefits of restoring two native pinewood forestsin Affric and Strathspey. If only the willingness to pay (WTP)of those who supported the restoration plan was considered,the average benefit estimate per household was £35 forAffric and £53 for Strathspey. When the compensation requiredby a small proportion of respondents who preferred the currentmoorland landscape, was estimated mean WTP was unchanged forAffric, but fell to £24 for Strathspey. The study highlightsthe need to take account of non-market benefits and costs whenevaluating land use change, otherwise benefits may be overestimatedand there is a possibility that the wrong projects will be selected.The sensitivity of CV values to the scope of the environmentalchange are also investigated and the issue of embedding discussed. 相似文献
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SUMMARY Reproductive performance was compared between cows whose previous parturition was induced and non-induced cows with similar calving dates, in 49 winter-calving, pasture-fed, commercial dairy herds in south-western Victoria. Parturition was induced in winter when most cows were between 27 and 35 weeks of pregnancy. Reproductive performance was assessed during the next mating period after induction which was mainly in spring of the same year. Percentages of cows in induced and untreated groups that were not pregnant after the mating period (9.0% and 7.2%, respectively) did not differ significantly. Induction tended to increase the percentage of cows of unknown pregnancy status. Mean percentages for induced and untreated groups were 11.5% and 7.9%, respectively. Induced and untreated groups calved at similar intervals after the planned start of calving in the following year, and the percentages of groups that required induction in that year did not differ significantly. The direct effects of induced parturition on reproduction were therefore concluded to be minimal. In seasonal calving herds, improvements in reproductive performance could be expected among cows whose calving dates were altered substantially by induction, due to increased intervals from calving to mating start date . 相似文献
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SUMMARY The effects of induced parturition on clinical disease and mortality of cows were studied in 51 winter-calving, pasture-fed, dairy herds in south-western Victoria. Parturition was induced when most cows were between 27 and 35 weeks of pregnancy. Control groups were selected from herdmates that were not induced to calve. The incidence of retained placenta was much greater among induced cows of all ages. The proportion of cows affected by any clinical disease other than retained placenta, and the incidence of mortality were much greater after induction among cows aged over 6 years but not among cows aged 3 to 6 years. 相似文献
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