Download ECONOMIC COST OF LAMENESS IN IRISH DAIRY HERDS

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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
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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.