title: The economic benefits of disease triggered early harvest: A case study of pancreas disease in farmed Atlantic salmon from Norway.
abstract: Pancreas disease (PD) is an important viral disease in Norwegian, Scottish and Irish aquaculture causing biological losses in terms of reduced growth, mortality, increased feed conversion ratio, and carcass downgrading. We developed a bio-economic model to investigate the economic benefits of a disease triggered early harvesting strategy to control PD losses. In this strategy, the salmon farm adopts a PCR (Polymerase Chain Reaction) diagnostic screening program to monitor the virus levels in stocks. Virus levels are used to forecast a clinical outbreak of pancreas disease, which then initiates a prescheduled harvest of the stock to avoid disease losses. The model is based on data inputs from national statistics, literature, company data, and an expert panel, and use stochastic simulations to account for the variation and/or uncertainty associated with disease effects and selected production expenditures. With the model, we compared the impacts of a salmon farm undergoing prescheduled harvest versus the salmon farm going through a PD outbreak. We also estimated the direct costs of a PD outbreak as the sum of biological losses, treatment costs, prevention costs, and other additional costs, less the costs of insurance pay-outs. Simulation results suggests that the economic benefit from a prescheduled harvest is positive once the average salmon weight at the farm has reached 3.2kg or more for an average Norwegian salmon farm stocked with 1,000,000smolts and using average salmon sales prices for 2013. The direct costs from a PD outbreak occurring nine months (average salmon weight 1.91kg) after sea transfer and using 2013 sales prices was on average estimated at NOK 55.4 million (5%, 50% and 90% percentile: 38.0, 55.8 and 72.4) (NOK=€0.128 in 2013). Sensitivity analyses revealed that the losses from a PD outbreak are sensitive to feed- and salmon sales prices, and that high 2013 sales prices contributed to substantial losses associated with a PD outbreak.
authors: Norwegian University of Life Sciences, Department of Food Safety and Infection Biology, P.O. Box 8146 Dep, 0033 Oslo, Norway. Electronic address: Jostein.Mulder.Pettersen@nmbu.no.
authors: J M
authors: JM
authors: Pettersen
authors: Norwegian University of Life Sciences, Department of Food Safety and Infection Biology, P.O. Box 8146 Dep, 0033 Oslo, Norway; Lab 863 Ltd., Wisteria Camrose House, 2A Camrose Avenue, Edgware HA8 6EG, United Kingdom.
authors: K M
authors: KM
authors: Rich
authors: Norwegian Veterinary Institute, Ullevålsveien 68, P.O. Box 750 Sentrum, N-0106 Oslo, Norway.
authors: B Bang
authors: BB
authors: Jensen
authors: AquaGen AS, P.O. Box 1240, Sluppen, 7462 Trondheim, Norway.
authors: A
authors: A
authors: Aunsmo
mesh_terms: D000818:Animals; D017756:Aquaculture / Q000191:economics*; D003365:Costs and Cost Analysis; D004196:Disease Outbreaks / Q000191:economics / Q000662:veterinary*; D005393:Fish Diseases / Q000191:economics* / Q000453:epidemiology / Q000821:virology; D018803:Models, Economic; D009664:Norway / Q000453:epidemiology; D010182:Pancreatic Diseases / Q000191:economics / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology; D016133:Polymerase Chain Reaction / Q000662:veterinary; D012307:Risk Factors; D020317:Salmo salar
keywords: Aquaculture; Atlantic salmon; Disease management; Economic benefit; Pancreas disease; Stochastic modelling