Leptospira are mainly spread through the urine of infected animals like rats, mice, pigs, and cows. In the case of abortion in sows, fetuses and attached tissues are extremely infectious.

Leptospira enter the body through small cuts or abrasions. The bacteria live in the kidneys and reproductive system. An infected animal can remain infectious for a very long time.

Since the clinical signs of the disease and the level of severity are variable; the disease is classified by clinical and subclinical symptoms:

  • The reproductive failure pattern is more insidious than sudden.
  • It is characterized by an increase in the “litter scatter”* figures, or abnormally small litters.
  • Some abortions can be seen while there is also an increase in the returns-to-oestrus.
  • In many cases it goes completely unnoticed.

* Litter scatter is the percentage of litters that have less than 7 piglets. The percentage should not be higher than 15%.

In sows
  • Fever, weight loss, diarrhea and MMA.
  • Presence of blood in the urine of the animals.
  • Yellow skin and mucous membranes.
  • Serious reproductive failures include abortions, increase of returns-to-oestrus, emergence of dirty sows, stillbirths and mommies.
In Piglets younger than three months
  • Presence of high fever, blood in urine, convulsions and yellow skin.
  • The majority of the piglets recover without treatment in less than a week, but some animals may die.