Lameness in dairy cows: Impact of practical nutritional and environmental management

Our thanks to the author and Conference Organisers, a Committee consisting of both University and Industry colleagues.

The full paper will appear in the Conference Proceedings ('Recent Advances in Animal Nutrition - 2007', edited by Phil Garnsworthy and Julian Wiseman) published by Nottingham University Press in the autumn of 2007 www.nup.com

Courtesy of the 41st Annual University of Nottingham Feed Conference www.nottingham.ac.uk/biosciences/ah/research/conferences.php


Lameness is undoubtedly one of the most serious disease problems currently facing the UK (and world) dairy industries in terms of its impact on welfare and decreased productivity. This paper will review the current UK situation and then describe the impacts of practical nutritional and environmental management on lameness.


Incidence and Prevalence

Over the last twenty years, the annual UK reported incidence of lameness has ranged between 17.0 and 68.9 cases per 100 cows per year. Locomotion scoring is currently the most widely accepted method for identifying lame animals. Based on the results of a number of studies using locomotion scoring the prevalence of lameness on UK dairy farms has recently been demonstrated as approximately 25.0%.


Common Foot Lesion

There are many different causes of lameness in dairy cows; however the vast majority are caused by foot lesions (~90%). In one study which investigated the causes of 9645 cases of lameness the most common causes were sole ulcers (28%), white line disease (22%), local sole bruising (8%), digital dermatitis (8%), foul in the foot (5%), interdigital hyperplasia (5%) and foreign body penetrations (5%). Since this study took place, the incidence of digital dermatitis has increased; it is now one of the top three causes of lameness along with sole ulceration and white line disease.


Financial and Welfare Implications

Lameness is associated with a significant impact on farm profitability. It has been calculated that the average case currently costs the UK dairy industry £172. Recently the impact of a case of lameness on future milk yield during that lactation demonstrated that the total mean reduction per 305 day lactation was 390 kg.

Lameness also represents a significant welfare problem; the fact that animals alter their gait in response to the discomfort caused indicates that lameness is a painful condition and this has been confirmed by previous work which demonstrated that lame cows are more sensitive to pain. Many consider that lameness is currently the most significant welfare issue affecting dairy cattle in the UK because of the level of discomfort caused, the numbers of animals affected and the duration of clinical episodes (demonstrated to be 27 ± 19 days in one study).


Aetiology of Common Claw Lesions

Lameness in dairy cattle is a multifactorial condition both because of the different diseases that cause it, and because of the huge differences between farms. The remainder of this paper will concentrate on some of the ways that practical nutrition can impact on lameness.

Shearing and abrasive forces applied to the hoof capsule
Abrasion thins the sole and shearing forces physically tear the white line apart making it easier for environmental debris to penetrate the resultant deficit leading to disease.

Shearing and abrasive forces usually result from either badly designed environments which force cows to turn sharply, or negative social interactions e.g. fighting and bullying. Increases in herd size, movement between groups and poorly designed feeding areas i.e. inadequate space allowance or areas with poor cow flow, all lead to negative interactions which can result in lameness.

Standing time on concrete and other hard / abrasive surfaces
Standing time on concrete is increasingly thought to be one of the most important causes of sole ulceration and WLD because of the relentless pressure that is applied to the support structures of the foot.

Cubicle comfort is probably the single most important driver of lying time and therefore reduces the standing time on concrete. However, modern cows are spending increasing amounts of time feeding and waiting to be milked as a result of the increase in average yield and herd size. The use of rubber floor matting, as an alternative to concrete, is now increasingly common in some parts of the world. It is either laid throughout the unit or in standing areas such as the collecting yard and feeding areas.

Walking surfaces
The quality of the walking and standing surfaces has three principal impacts on lameness:
• Poor quality surfaces covered in debris can predispose animals to WLD e.g. tracks used to access pasture.
• Broken and damaged concrete can cause slips and trips, which increase the pressure on the foot and can cause shearing forces as the animal attempts to maintain its balance. Additionally broken areas of concrete pool stale slurry, which becomes an excellent method of transmitting digital dermatitis.
• Smooth and glassy areas of concrete can cause animals to slip.

Nutritional management
Despite recent changes in the proposed aetiology of “sub-clinical laminitis”, controlling subacute ruminal acidosis remains an important aspect of lameness control in cattle. Even if a diet is formulated to ensure adequate fibre intake, practically these intakes may never be met by some animals, especially if concentrates are introduced too soon after calving or subordinate animals fail to meet their target forage intakes because of bullying or poorly designed feeding areas.

Contact with slurry
Contact with contaminated slurry is one of the most significant risk factors for the acquisition of digital dermatitis. Whilst of course faecal production is related to nutrition there is very little that can be practically done to control or limit its production. However, as yields and dry matter intakes increase the resultant increase in faecal volumes must be considered. Herd owners should be encouraged to increase the frequency with which housing is scraped to reduce the exposure of cows to large quantities of slurry.


Conclusions

Lameness in dairy cattle is multifactorial in origin and currently represents a significant challenge to the UK dairy industry. This paper has reviewed some of the factors associated with claw and foot lesions in dairy cattle, particularly those associated with practical nutrition.


Author: Jon Huxley
University of Nottingham School of Veterinary Medicine and Science