The cost of lameness to the average Irish dairy farm is estimated to be up to over €4,000 annually, according to new analysis.

A new paper published by the Veterinary Ireland Journal puts the figure for a sole ulcer in a cow’s foot at €536.52, taking into account a wide range of factors.

These include the price of treatment, the farmer’s time, reduced milk yield and indirect costs.

A moderate prevalence of sole ulcers causing lameness, eight cases annually, in the average 100-cow herd costs €4,292.16.

A single case of white line disease costs a dairy farmer €226.67.

Ten cases per year, which is said to be a moderate level of infection for a 100-cow Irish dairy farm, costs €2,266.70.

The figure for a case of digital dermatitis is €201.14, costing the average herd with an average incidence of the disease €2,011.40 annually.

A recent study cited by the paper said the best-performing Irish dairy farms had less than 5% lame cows in their herds.

Pasture-based system

The paper by Teagasc researcher Muireann Conneely and University College Dublin (UCD) veterinary professor Eoin Ryan added that recent Irish research showed the average prevalence of lameness on Irish dairy farms was 9%.

This compares favourably with other countries.

However, all Irish studies have shown considerable inter-herd variation.

It was also highlighted that pasture-based dairy systems have a significantly reduced incidence of lameness than herds that are housed.

“Estimates range from as low as 3.8% in year-round, pasture-based systems (Beggs et al, 2019) to 63% in fully-housed systems,” the paper said.

Referencing research, Conneely and Ryan said it is considered that intervention is needed when a lameness prevalence is above 10%.

Economic cost

The Veterinary Ireland Journal paper highlighted that the economic cost of lameness is “significant”.

“Lameness is estimated to be the third-most costly health issue of dairy cows after mastitis and fertility (Bruijnis et al, 2010).

“The costs arise both directly and indirectly - direct costs include additional expenditure that is directly linked to the case of lameness (such as additional farm labour, cost of hoof trimming and veterinary treatment, decreased milk production and the cost of milk withdrawal if milk has to be discarded owing to drug treatments), while indirect costs arise due to the side effects of lameness.

“These include reduced reproductive performance and early culling,” the paper added.

Conneely and Ryan said the greatest costs related to the disease are generally losses in production, such as reproductive performance and milk yield.

“These costs may be the ones of which farmers are the least aware, as they do not have to pay directly for them at the time,” they said.

The welfare cost to the cow was highlighted, as lameness can cause huge discomfort and pain.

Lameness and milk yield

There are numerous studies showing that lameness lowers milk yield.

This is because lame cows spend more time lying down instead of eating and also the stress-hormone cortisol can negatively affect rumen function.

The paper added that the time of year at which the lameness occurs is critical.

“If the lameness occurs once peak lactation has passed, the effects on total milk production over the course of the lactation will be less than if the lameness episode occurs before peak production.”

Higher-yielding cows will have a greater reduction in yield and are also at greater risk of becoming lame.

“Many studies report milk losses occurring up to five months after the diagnosis of lameness (Green et al, 2002), while more recent research has shown that yields can drop as much as three months prior to diagnosis (Amory et al, 2008; Green et al, 2010).

“Identifying lameness earlier means the lesion will be at a less severe stage when treatment is instigated; cows will recover from lameness more quickly (Leach et al, 2012) and milk production losses can be minimised.”

The paper also highlighted that lameness negatively affects reproductive performance and that lame cows are more likely to be culled.