Mastitis detection, prevention and treatment

A vet in action checking up a calf in Nakuru PHOTO: BONIFACE THUKU

Picture this scenario: You are a dairy farmer and have this healthy cow that is a super milk producer. The cow — whichever breed — produces so much milk you are the envy of fellow farmers in the village.

But one morning, you notice something as you are milking the cow — A significant drop in the animal’s milk production.

On close examination, the animal that was normal the previous day, has an unusually warm udder or even cold udder.

As you continue milking the cow, you notice droplets of blood in the milk or some clots.

Sensing something could be terribly wrong with your dear cow, you examine it more closely and realise the udder is swollen, reddened and may be painful to touch. The animal could react to the pain with kicks or continuous movement in discomfort.

Worried, you call the vet and he diagnoses that the animal has mastitis. Today I will shed more light on mastitis, symptoms, prevention, treatment and control.

Nature of disease

Mastitis in dairy cattle is the persistent inflammatory reaction of the udder tissue. It is a potentially fatal mammary gland infection.

It is caused by infectious bacteria which is the main cause or non?infectious agents like trauma to the udder.

The infection causes major losses as it leads to decreased milk production, premature culling of cows usually the high yielding ones, replacement as well as discarding and down?grading of milk and sometimes death of affected animals.

The disease can affect a single animal in a farm or can at times occur as an outbreak.

High occurrence of mastitis is a major challenge to the dairy sector in Kenya and globally, a problem compounded by lack of a mastitis control programme and poor hygiene during milking.

Mastitis affects all animals with mammary glands including humans but is common in dairy cattle and goats. In both species of animals, mastitis can occur at any time during lactation but is common in early lactation.

Bacteria that cause mastitis come from the environment of the animals and that is why hygiene remains the most successful method to control the infection, which occurs through the teats.

Main sources of infection include bedding, the milkers’ hands, milking towels and milking equipment.

Prevention and control

Mastitis can either occur as a detectable infection with pronounced clinical signs known as clinical mastitis or a subtle infection known as sub clinical mastitis.

Sub-clinical mastitis is most common but clinical mastitis leads to severe reduction in milk production. Cleanliness is known to reduce mastitis cases. So how can this cleanliness be achieved?

First, milkers need to wash their hands thoroughly before and after milking each cow and use a separate clean udder cloth or a disposable tissue for cleaning each cow.

It is also important to treat a cow just before the beginning and during the dry period known as Dry Cow Therapy. It is done after the last milking of the cow before the dry period.

This makes use of antibiotics and teat sealants to kill any bacteria that could occur as reserves during the dry period and therefore cause mastitis in the next milking season.

Another important precautionary measure to take is Post?Milking Teat Dipping treatment. This is the most effective in stopping the spread of mastitis in a herd and preventing bacteria from entering the teats soon after milking when the teats sphincters are still open. Dip every quartre individually.

Culling chronic mastitis cows is recommended for cows having four or more episodes of mastitis in one lactation period. In cows with some healthy and some infected quartres, the chronically infected quartre should be cauteriaed/killed and then one will continue milking the healthy ones.

Start with clean animal

A proper order of milking cows should be executed in which the milker always starts with the clean animals/herd.

Cows with mastitis should be milked last and the same should apply to any infected quartre.

Regular laboratory testing for mastitis in the herd is also advised and this usually involves testing to know if any bacteria are in the milk.

Treatment

Mastitis is effectively treated by use of antibiotics, administered either through injection (systemic) or infused into the teat canal (intrammamary). Milk from cow under medication is not marketable due to drug residues until the recommended milk withdrawal period is completed.

Because of that potential danger, there is need for antibiotics in mastitis treatment to be handled by qualified individuals to avoid drug resistance in animals and humans who consume milk from mastitis animals undergoing treatment.

Milk from such animals should be discarded and not even fed to calves.

Before treatment, a bacterial culture and sensitivity testing should be conducted to ascertain the drugs that the bacteria in question could be most susceptible to.

Every farmer should insist on these lab tests as they reduce chances of antibiotic resistance.

The most commonly used drugs in mastitis are intemammaries.

When administering antibiotics using the intramammary method, first empty the udder of any milk and clean the tip of the teat.

When done with that, place the tip of the tube into the teat and squeeze all the antibiotic inside then massage the teat and udder to distribute the medication.

In conclusion, mastitis is a disease that affects production leading to losses for small holder or large scale farmers, this calls for continuous testing of herds before milking or at regular intervals.

- The writer is a veterinarian surgeon at the University of Nairobi