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13 Ger Cusack, Comeragh Veterinary and Chairman of XLVets Economic cost of lameness in Irish dairy herds As a vet in practice in a strong dairy county like Waterford, I spend a lot of my time treating lame cows and advising farmers on the prevention of lameness. Over the years I have developed a special interest in the costs, causes, treatment and prevention of lameness on dairy farms. A greater appreciation of the significant effect that lameness can have on farm profitability would help motivate farmers to take a more active approach to treating and preventing lameness. The incidence of lameness on dairy farms across different countries has been widely studied and surveys have shown a big variation from farm to farm (from 15 to 50 per cent). In the average Irish dairy herd, 20 out of every 100 cows are affected by lameness in any given year. On average, an affected cow will have 1.4 cases of lameness. This means that there will be 28 episodes of lameness in the typical 100-cow herd. Lameness has both direct and indirect costs associated with it. The combination of both results in a total cost of approximately €300 per affected cow. The costs associated with lameness are calculated here based on work done by Eoin Ryan MVB and Luke O’Grady BVMS MRCVS of UCD in 2004 when they studied the Economics of Infectious and Production Diseases in Irish Dairy Herds. The costs can be divided into direct and indirect costs. Most of the direct costs of a single case of lameness are easy to 14 Table 1. Cost of Lameness per case (Digital lameness) Direct Costs Unit Cost/ Unit(€) Cost of Treatments (drugs, dressings, shoes etc.) Vet’s Time (Minutes) @ €104.30/hr Total (€) 8.50 15 Average Callout Charge per cow (4 cows @ callout) Cost of farmer’s time (Minutes) @ €20/hr 20 Cost of Milk Withdrawal (AB used in 10% of cases) 0.1 Four days’ milk @ 23 litres per day (92 litres x 10%) @ €0.35 per litre 9.2 Cost of reduced milk yield 500L 104.30 26.80 40.00 10.00 20 6.66 3.22 0.15 margin/L 75.00 960.70 105.68 Indirect Costs: Cost of increased culling @ 11% cases culled Cost of culling a cow (lame cows generally of low salvage value) Extra days added to Calving Interval @€3.93/day 9 3.93 35.37 Cost of extra services 0.39 29.80 per straw 11.62 Total Cost of a case of Lameness 282.85 Total Cost of 1.4 cases per cow 302.43 quantify. The cost of treatment, the vet callout and time charge, the cost of farmer’s time, the milk discarded and the loss of milk sales for the remaining lactation are the direct costs. The reduction in milk yield is based on estimates by Esslemont and are made on the basis of 3-5L reduction for three-to-seven weeks and are comparable to 7 per cent overall lactation yield reduction. Indirect costs of lameness are more difficult to measure. Lameness reduces the cow’s mobility and causes loss of body condition through reduced feed intake. This affects the cow’s fertility in the following ways: • loss of body condition; • inability to show sign of heat; and, • increased likelihood of being hurt during bulling activity. The reduction in fertility is related to the severity of the lameness and manifests itself in a number of ways. Lame cows show increased mean calving to first service and calving to conception intervals. These cows Type of lameness Digital Interdigital Solar ulcer Average case Prevalence (%) 45 35 20 Cost (€) Cost (€) Cost (€) Cost (€) Total cost of a single case 282.85 136.12 504.58 275.26 Total cost of 1.4 cases 302.43 152.46 535.78 296.61 require more services and typically one in five cows with a mild lameness require an additional service. In severely lame cows, almost three out of every four require an additional service. With mild transient lameness, the number of days added to the calving interval is low, typically eight-to-10 days. However, a cow affected with more severe chronic lameness such as solar ulcer, may require an additional 40 days to go in calf. Most cases of lameness are treatable. However, there is a significant risk that a cow with a history of lameness will be culled. Up to 18 per cent of cows with solar ulcer are culled prematurely. After infertility and mastitis, lameness is the third most common reason for culling cows on Irish dairy farms. Lameness can be divided into three major categories: 1. digital or hoof lameness (white line disease, solar haemorrhage, laminitis, slurry heel); 2. inter-digital infections (digital dermatitis, foul-in-the-foot, inter-digital dermatitis); and, 3. solar ulcers. An extra case of lameness in an already affected cow will increase the direct cost of the vet and farmer’s time, along with the cost of drugs and waste milk from withdrawals. The reduction in milk yield will, however, remain the same. Similar costing exercises have been done for inter-digital lameness and for sole ulcer lameness. As discussed in the opening paragraph, the typical 100-cow Irish dairy herd will have 20 cows affected by lameness over a 12-month period. On average, an affected cow will have 1.4 episodes of lameness annually. The cost to a typical 100-cow herd are: No. Cows affected: 20 1.4 episodes of lameness @ €296.61 per cow 20 x €296.61 = €5932.20 Cost per cow across herd €60 The losses associated with lameness as outlined are a significant drain on profits and farmers, to whom I have shown these figures, are consistently surprised by scale of the losses. On the majority of farms, the impact of lameness on profit can be significantly reduced by adopting a planned approach. Control centres on firstly, reducing the number of cows affected and, secondly, dealing promptly and effectively with the cows that become affected to minimise the production loss.