Assumptions | Definitions/Notes | Parameter values |
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Forecast of business as usual production of sheep, cattle, sheepmeat, beef, milk, wool and prices of the above in Scotland. [B,C] | Ex ante evaluation there is the need to make forecasts | Autoregressive integrated moving average ( ARIMA)time series forecasting technique was used to make all forecasts of trade data up to 2013. |
Veterinary and medicine costs [C] | It is assumed that veterinary treatment of animals is good husbandry practice, which is helping to keep diseases out and reduce deleterious effect of disease when it occurs. Veterinary and medicine cost extracted from SAC farm management hand book 2007 | General veterinary and medicine for sheep and cattle £3/head and £12/head for sheep and cattle respectively |
Veterinary services [C]: PCR, ELISA for pre-testing of imports from BTV-affected countries and from the RUK [B]: PCR, ELISA for pre-testing of domestic livestock due to movement restrictions | Pre-movement testing and BTV vaccine cost for sheep and cattle. Information supplied by Scottish Government ( SG). | PCR (£15/head), Pre-movement testing ELISA (domestic) (£3/head), BTV Vaccine per sheep (£0.5/head), BTV vaccine per Cattle (£1/head); |
Voluntary and compulsory vaccination [B] | Government strategy to the uptake of vaccination can be either compulsory or voluntary depending on BTV control option. Where 100% uptake was evaluated, vaccination was assumed compulsory. | Cost of uptake of voluntary and compulsory vaccination was obtained from Scottish government as follows: Mail shot to all livestock holders £35,000-This cost applies to all Scotland coverage, and was scaled to the relevant coverage of PZ used in the control option (i.e. 100%, 80% or 50% vaccination) Specialist media (advertising) £25,000- Cost of advert placed in the Scottish Farmer- this applies to voluntary programmes (i.e. 80% and 50% vaccination) Mail shot to all vets £500-This applies to all 170 large animal practices in Scotland. Animals for export are vet administered and certified - 1 st cattle (£50), next 9 (£10 each), the rest (£5 each). 1 st sheep (£50), next 9 (£10 each), the rest (£1.50 each). If voluntary, all other animals are farmer administered - Vet expenses are estimated as £80 per holding as cost of vet time for prescription and supplying of vaccination. Costs of legislation and random monitoring in the case of compulsory vaccination were not included. |
Carcase disposal cost [B] | The burial or burning of animal carcasses within EU Member States is banned. The only legal methods of disposal of diseased animal carcasses are by rendering or incineration. 5 On farm incinerators are allowed providing they conform to certain standards and are approved. Incineration of animal carcasses attracts costs. Data from Defra (2007) | Carcase disposal cost was assumed to be £75/head and £20/head for sheep. ( BTV casualties) |
Fertility [B] | Dairy based on Santarossa et al. (2004), beef on Gunn et al. (2004) and sheep on Conington et al. (2004). Note these figures exclude impacts of fertility on production to avoid double counting. This explains why beef > dairy. | Loss of fertility for beef cows (£2.7/head), Loss of fertility for dairy cows (£2.5/head), Loss of fertility for sheep (£0.60/head). Mean for ALL head on infected farms. |
Wool loss [B] | In some flocks, no clinical sign is apparent, whereas in other flocks infected by the same virus up to 30 % may develop signs of disease. Sheep that recover from BTV infections may render wool fragile and in some cases this can lead to partial or complete shedding of wool. 6 | An average of 2.5 kg of wool is produced per sheep. Wool not sheared from 30% of BTV infected sheep. 7 |
Weight loss (morbid animals) [B] | There is no guidance in the literature on the degree of weight loss in morbid animals. A lower and an upper band of weight loss is assumed for sheep and cattle. Our assumptions are drawn from personal communications with experts in various countries. | 9% of infected cattle and 11% of infected sheep would show weight loss. Cattle: a lower bound of 10% and upper bound 15% of sheep biomass is lost due to BTV infection. a lower bound of 5% and upper bound 10% of cattle biomass is lost due to BTV infection |
Milk loss (morbid animals) [B] | Personal communication with J.Winkelmann suggests 15% milk loss with a range of 10% to 30% but up to 50% for acute cases over a 100 day period (say 1/3 rd of lactation). With a lactation yield of 8800 kg this works out at about 400kg milk lost per morbid animal i.e. about 5% of whole lactation yield. | 5% of milk is lost due to BTV infection |
Surveillance cost [C] | Animal disease surveillance and control costs were obtained from SG recorded in financial year format. To make these data compatible with the rest of the data it was taken to represent calendar years. | There is no specific public sector cost dedicated to the surveillance of BTV. Therefore it was assumed that 2% and 0.5% of total public sector surveillance constitute passive surveillance costs for sheep and cattle respectively. |
Palliative care cost [B] | Palliative care is any form of medical care or treatment that concentrates on reducing the severity of BTV disease symptoms. The goal is to prevent and relieve suffering and welfare in that condition. It was assumed that 600 kg cow would require a dose of (60 ml per 600 kg bodyweight) of alamycin la 8 and fluxin. 9 Since sheep are the most susceptible to BTV, it is assumed that a 80 kg sheep would require doses of alamycin la and fluxin for 5 and 3 days respectively. 89 | Cow Alamycin la] £12.60; Flunixin £8.48 Sheep Alamycin la £1.68 (x5 days), Flunixin £2.55 (x3 days ) |
Compensation to farmers [B] | Slaughter of animals due to BTV related health reasons with compensation deemed to be unlikely (Scottish Government) | Compensation unlikely |
Labour costs [B] | It is assumed that family labour will be used to supplement farm labour in the event of an incursion of BTV. | As family labour has a low opportunity cost, labour cost was assumed to be £1/hour as in Gunn et al. (2004). Extra labour 2mins/morbid sheep and 7mins/morbid cattle per day. |
Movement restriction [B] | Zoning regulations apply in the event of an outbreak. | Assumed that movement restriction will cost 5% of the value of the animal. (Defra, 2007) |
Prices and quantity relationship [B] | The apparent reduction in demand by beef and sheep meat consumers was modelled using relevant estimates of price elasticity of demand. Price elasticity of demand is the degree of responsiveness of price due to a change in demand. Thus the magnitude of the fall in consumption of beef and sheep meat due to BTV outbreak would depend on the responsiveness of beef and sheep meat demand to changes in their prices. These relationships are usually measured over relatively small price and quantity changes; it is likely that a similar price and quantity relationship will hold for a much larger increase in price (Fofana et al. 2004). 10 | Own price elasticities used to simulate the effects of change in domestic consumers' perception of Scottish animal production as a result of BTV incursion. Own price elasticities were extracted from Defra 11 as follows: beef -0.92, Sheepmeat -1.29 and Milk -0.17. Corresponding price changes were assumed to be £0.25 and £0.10 for beef and sheepmeat. Milk price was assumed to decline by 4% in year 1 but this effect was reduced to 3%, 2% 1% and 0% in years 2 to 5 respectively. |
Duration of trade impact [B] | Cost component of all items depend on the duration of outbreak and time taken to eradicate the disease | Modelled on the duration and re-occurrence of BTV from epidemiological model output |
Input-Output multipliers [B] | Multipliers are commonly used in economic studies which attempt to show how important one business or industry is to a given geographic region or community. Multipliers are numbers which measure the magnitude of the direct and indirect effects that a given amount of production (in this case trade restrictions or export ban) has on a region (Scotland). Mahul and Durand (2000) used multipliers to simulate the effects of international trade ban in FMD outbreak in France. Multipliers were extracted from Scottish, Economy Statistics - Input-Output Tables 2004 | Input-Output multipliers used to simulate the effects of export ban on live animals. |
International trade in live animals [B,C] | International trade in live animals are the most affected during an outbreak of BTV. | Assumed 75% of international imports of live animals are from BTV affected countries which need pre testing and 100% of imports of live animal from the rest of UK need pre testing. |
Discount rate [B,C] | A discount rate is the percentage by which the value of a cash flow is reduced for each time period by which it is removed from the present. It is used to bring all future values to the current time or period. | Official UK guidance on the choice of a discount rate is given in HM Treasury Green Book. The HM Treasury's 'core' social time preference discount rate is currently 3.5%. |
Probabilities [B] | | See special note below. |