Comfy secret to reduce mastitis
Practical solutions could
cut mastitis and lameness,
producers at an MDC
organised farm visit were
told. Richard Allison reports
MAXIMISING cow comfort around calving is the secret to minimising cases of lameness during the first three months of lactation, according to a Glos-based vet.
Speaking to producers at last weeks MDC meeting near Leominster, Herefordshire, Roger Blowey stressed the hoof is more susceptible to infection and damage at calving.
"Research data, involving more than 1000 cow years, shows that most cases of lameness occurs 2-3 months into lactation. This is often blamed on stress at peak milk production, but what is being observed may have happened about two months ago."
It takes a couple of months for lesions occurring inside the foot to reach the weight-bearing surface of the foot and cause sole ulcers, said Mr Blowey. He believes the main cause of these ulcers is the pedal bone pinching the soft inner corium area of the foot onto the hard sole beneath.
The corium can also become infected due to white line disorders. The white line is a cemented junction between the wall and sole of the hoof and is a point of weakness which allows infection to gain entry into the hoof.
Mr Blowey said cows were more susceptible to foot damage at calving because horn growth is severely disrupted at this time, resulting in the sole becoming thin and the corium being at greater risk of damage.
"The ligaments supporting the bone in the hoof are also more relaxed in the last two weeks of gestation and first four weeks of lactation, increasing pinching of the corium by the pedal bone."
The type of housing at calving will affect the incidence of lameness later in lactation. A common mistake is to calve heifers outside and then bring them into the herd on that same day, said Mr Blowey. "They are transferred from an ideal soft surface onto hard concrete."
To minimise damage, producer Hugh Black calves all cows and heifers in straw yards at Wharton Bank Farm, Herefordshire, to provide a soft surface. "This minimises pressure on their feet."
His heifers are also trained to use cubicles around insemination at 18 months old and they join the dry cow group two weeks before calving to ensure they are settled within the herd. This prevents heifers standing around excessively at this crucial time, said Mr Black.
Hock damage was also a common problem when cows were housed on concrete cubicles bedded with straw.
"No matter how much straw was used, cows constantly kicked it off the bed into the scraping passage to reveal a hard surface," said Mr Black, who switched to cubicle mats last year for the 170-cow herd. "Cows are now more comfortable, hock damage and sole ulcers are no longer seen."
When assessing cubicles for comfort, watch how cows behave, says Mr Blowey. "Do they look comfortable? Cows wriggling forward while lying down is a sign of poor comfort."
When cows stand half out of the cubicle with their back feet in the slurry passage it can be due to having open fronted cubicles with cows on the other side. "Cows prefer to have nothing in front of them," he adds.
Automatic scrapers were also fitted at Wharton Bank Farm, clearing passages every two hours directly into a slurry lagoon outside the housing area.
Mr Blowey believes this is crucial for controlling digital dermatitis. "Research shows mixed urine and slurry presents a greater risk of digital dermatitis than when unmixed. But cows must not be forced to walk through pools of scraped slurry deposited at the end of the building." *
Cows are at highest risk of foot damage around calving time, but good housing can reduce lameness cases, says Roger Blowey.
• Hoof fragile around calving.
• Calve on straw.
• Train heifers in cubicles.