“MASTITIS is probably the most important animal welfare issue in the dairy industry,” according to Dr Herman Barkema of the department of veterinary medicine at the University of Calgary in Canada.
Speaking at a seminar in London last month (which was beamed to other centres in Europe), organised by Pfizer Animal Health to mark the 10th anniversary of the launch of OrbeSeal, he said that one in four cows was affected, the frequent treatments required were not nice for the animals and cases, particularly of acute clinical mastitis, could cause a great deal of pain.
The challenges faced by both veterinary surgeons and farmers were to decrease the incidence of mastitis, decrease its severity, increase the cure rate and get as rapid a cure as possible, and decrease the pain involved.
There had been very few studies on mastitis and pain, Dr Barkema said, but evidence showed that use of NSAIDs, particularly in chronic cases, increased the cure rate and led to fewer cows being culled.
He called for pain in mastitis to become an important research focus.
Dry period infections
Professor Martin Green of the Nottingham veterinary school and a partner in the Orchard Veterinary Group in Glastonbury, spoke
about the influence of the dry period on clinical and sub-clinical mastitis in dairy herds. The dry period was a critical time for mammary health, he said, during which existing infections could be cured and new infections prevented.
“It is the best time in a cow’s life for curing chronic infections,” he said, and he referred to research in the late 1990s that showed that, in commercial herds in the UK, dry period infections could remain until lactation and then cause clinical infections. In some herds dry period infections accounted for well over 75% of both clinical and sub-clinical mastitis.
“You have to prevent infections in the dry period, otherwise it’s too late. Dry period infections are hugely significant: if you don’t prevent them, you won’t have much joy in controlling mastitis,” he said.
“Could mastitis be reduced by changing management during the dry period?” Prof. Green asked. “Yes,” he said. Existing infections could be cured very successfully with antibiotic dry cow therapy (ADCT) and new intra-mammary infection, in both infected and cured cows, could be prevented by the use of a combination of an internal sealant, antibiotics and good management.
“All products work better when farms are managed very well,” he added. Hygiene was very important in preventing new infections but traditionally there had not been enough attention paid to the environment. “It is important to take a holistic approach,” Prof. Green said.
An evolving disease
Dr Andrew Bradley, founder of QMMS and a clinical reader at the Nottingham veterinary school, discussed the evolution of mastitis and said that ADCT, which had been developed in the 1940s and been incorporated into the NIRD five-point plan in the 1960s, had been hugely successful.
Farmers should still be using ADCT, he said, but the outcomes and consequences could be different in different herds, in different cows and in the same cows in different herds.
There were shifting patterns, he said. A consequence of increased ADCT use is a potential increase in Gram-negative mastitis; while a consequence of decreased ADCT use is an increase in Gram-positive infections.
Environmental mastitis appears to be an increasing problem, he continued, but clinical mastitis was the main challenge on many farms.
Dry cow therapy, including sealant, was still a cornerstone of mastitis control but the over-zealous use of ADCT could have negative impacts on clinical mastitis control in the modern dairy herd.
Teat sealant use
Alberto Salvaneschi, Pfizer’s associate director of marketing, told the seminar that more than one-and-ahalf million cows a year in Europe were treated with OrbeSeal; and Niall Jaggan, the firm’s product manager for dairy, said he expected the product to become increasingly important in the future as a nonantibiotic solution.
Pfizer also released the results of a survey of 28 farms across Europe last year which showed that use of the product as part of a dry cow programme reduced labour costs per cow for clinical mastitis in the first six weeks of lactation by around 35%.
Other findings were that clinical cases of mastitis were reduced by 37% and systemic antibiotic use was reduced by 38%.