Mastitis is one of the most costly diseases in dairy farming. It is expensive to control especially at the chronic stage. Unfortunately, most farmers don’t know what mastitis is or even how to identify it.
What is mastitis and what causes it? What are the various stages of mastitis? Why is there a high mastitis prevalence in most farms?
What is mastitis?
Mastitis is an inflammation of the parenchyma of the mammary gland produced by infectious agents that infiltrate the udder, multiply, and produce toxins.
To date, more than 140 potentially pathogenic organisms have been identified that cause cow mastitis. The disease is divided into four categories based on the organism involved: bacterial, mycotic/fungal/algal, Mycoplasmal, and Nocardial mastitis.
Contagious mastitis is an intramammary infection (IMI) transmitted from a cow with an infected udder to a healthy cow.
On the contrary, environmental mastitis occurs when infections are caused by pathogens whose primary reservoir is the environment in which the cow lives. Most infections caused by environmental pathogens are clinical and short-lasting.
Mastitis is also divided into clinical (mastitis with visible symptoms) and subclinical (mastitis without visible symptoms) forms.
Clinical mastitis is characterized by the presence of indications of inflammation in the mammary glands, such as swelling, heat, pain, and oedema, as well as changes in the milk, such as flakes and clots.
Clinical mastitis further poses a hazard to animal welfare since it causes pain, a rise in mean rectal temperature, a rise in heart rate, and a rise in respiration rate.
Comparatively, subclinical mastitis is an inflammation of the mammary gland that occurs without obvious signs and can progress to clinical mastitis or vice versa.
Advance symptoms
This type of mastitis results in a no evidenced decrease in milk production, as well as changes in milk quality and content. Loss of quarter(s) or teat(s) might occur as a result of severe or chronic inflammation.
Cows with blind quarters produce less and are more likely to be killed early than their healthy counterparts.
Furthermore, the removal of milk from lactating animals with mastitis causes significant food losses resulting in nutritional insufficiency in children and nursing mothers. This ultimately results in diseases of nutritional deficiency. Read Also: how you can formulate your own high-yield dairy meal.
The classification of severity is based on the definitions of the International Dairy Federation.
Cases are classified as MS 1 (mild clinical mastitis) if only deviations in the nature of the milk (colour, consistency, and viscosity) appear.
If local inflammatory symptoms (swelling, induration, painfulness, redness, and increased warmth) are also present, cases are classified as MS 2 (moderate clinical mastitis).
MS 3 (severe clinical mastitis) is characterized by complementary general clinical signs of illness (fever, hypothermia, recumbence, and aversion to feeding).
Reference: Prevalence of Bovine Mastitis and Its Associated Risk Factors among Dairy Cows in Ethiopia during 2005–2022: ASystematic Review and Meta-Analysis
