Acute udder oedema occurs in high producing dairy animals but is
more severe in heifers. It starts a few weeks before calving
and can continue up to 3 weeks into lactation.
Oedema is characterized by an excessive accumulation of lymphatic
fluid in interstitial spaces. Visible accumulation sites include the udder, navel
and brisket regions, and in exceptional cases the thighs and
vulva. Udder oedema may interfere with milk production, milk
letdown, and machine attachment during milking. The teats tend to
strut outward so that milking can be more difficult. There can be
physical damage such as cracking of the skin on teats and harm to
suspensory ligaments, leading to broken down udders. Severe mammary
enlargement makes walking and lying down difficult and causes
discomfort to the animal.
The exact cause of udder oedema is not known. Factors such as
inheritance, circulatory disturbances, and diet are considered the
possible causes. Genetic factors may play a role because some dairy