Risk of lameness and mastitis rises with non-stop rain
Published 15/08/2012 | 06:00
The incessant wet weather is resulting in a number of negative effects on animals, feed, their environment, and farmers' wellbeing.
The only thing that seems to be flourishing this year is the noxious weed ragwort. All hopes now hang on a dry and growthy autumn. However, it's not just the combination of feed shortages and cashflow that are on the increase.
Lameness and mastitis due to environmental bacteria are also on the up. These will increase the pain of 2012 due to higher production losses, increased treatment costs, lower fertility and greater culling rates.
Wet conditions reduce the time cows spend lying down, increasing the stress on hooves as cows stand for longer periods.
Along with muddy conditions on roadways and paddocks, the wet weather has washed away the fine material of cow tracks.
This exposes the larger stones and gravel pieces which substantially increases the potential to damage the cow's hoof. The prolonged exposure to moisture also causes the hoof to soften. Softer hooves increase the incident of bruising, penetration injuries and white line disorders. The skin between the toes and around the foot also softens and can macerate, leaving skin more prone to infections such as foot rot and digital dermatitis.
The first step in dealing with lameness is identification and treatment. Early examination and treatment of a lame cow is important to limit the financial loss. To identify the lame foot, a simple rule is that when a cow is walking if she is lame in the front foot she will lift her head when she puts the lame front foot down. In reverse, if she is lame in the back foot she will drop her head when putting down the lame back foot, and will also have a smaller stride.
Remove any cow showing signs of lameness from the herd and place her in a paddock near to the milking parlour to reduce the distance walked and stop the injury becoming worse. Once-a-day milking is also an option. The next step is to determine the cause of the lameness. Lesions can be divided into two groups -- infectious such as digital dermatitis and foot rot, and non-infectious such as bruising, sole ulcers or whiteline and interdigital lesions. Footbathing and trimming are the best to manage the challenge to the hoof.
Strategies to prevent lameness are the final but most important step:
1. Patience moving stock.
Allow the herd to move slowly and pick their step especially where parts of the track are in poor repair. If practical, use an alternative route even though this may take longer. When milking, let the cows move into the parlour at their own speed. Soft hooves are easily worn by twisting and turning on abrasive concrete so avoid pushing the cows up tight.
2. Protect hooves from rough surfaces.
Areas of concrete that meet laneways or where a lot of turning happens should be washed down, brushed or covered with carpet or matting in the short term. Temporarily fix areas of tracks that have deteriorated during wet conditions especially the last 20-30m that leads up to the parlour or sheds.
3. Identify problem areas and plan necessary changes
In the long term, tracks should have a camber that promotes water run-off and suitable drainage either side of the track so that the water has somewhere to flow to. Trees and hedges that shade the track prevent drying. Tracks need to be as straight and fluid as possible.
Avoid sharp turns and angles these areas slow down cow flow and create wet boggy areas that stimulate cows to dung, which also subsequently degrades the track surface.
The combination of wet and humid weather with muddy tracks and cows being housed where grazing conditions have become too challenging have provided a great opportunities for environmental bacteria to grow and infect the udder.
The main bacteria causing environmental mastitis are Strep. uberis and E.coli.
These infections often cause a very severe clinical mastitis.
Strategies to minimise incident of environmental mastitis:
1. Use teat dip. This is your number one protection. Aim to cover the whole teat using 15ml per cow.
2. Although the first instinct is to wash udders which are covered in mud, it is often better just to dry clean, and concentrate on just cleaning the teat.
3. Use nitrile gloves whilst milking.
4. Fix areas around the farm (tracks, gateways, around troughs) that make udders muddy.
5. Where cows are housed, keep the cow housing, especially cubicle beds, clean and dry.
Dr Mary Kinston is a farm consultant based in Kerry. Email: firstname.lastname@example.org