UTERINE METRITIS
Species affected: Cattle
Metritis is the inflammation of the uterus, a reproductive disease caused by a postpartum microbial infection. It is one of the most common pathologies at cattle farms and can lead to other diseases, fertility issues and even death.
Over the three weeks pre- and postpartum, animals experience hormonal fluctuations and stress that make their immune systems less effective. Higher cortisol levels during calving are the main cause of lower defenses.
In the first week postpartum, bacterial contamination affects up to 90% of cows due to various factors:
Deficient hygiene during calving
Increases uterine contamination.
Metabolic and nutritional issues
May lead to uterine atony (hypocalcemia), making it more difficult to get rid of the pathogens and complicating uterus involution.
Improper care and uncomfortable or annoying environment for the animal
Increases stress and cortisol levels, which leads to greater immunosuppression and lowered defenses.
Heat
Increases stress levels and, therefore, immunosuppression.
Number of calves
With each calving, the probability of lesions and infections is greater due to loss of uterine elasticity and slower involution.
Twins
If the cow is carrying two or more calves, the risk of infection increases.
Placenta accreta
Decomposing tissue that hasn’t been expelled is a source of contamination that fosters bacterial growth.
Uterine prolapse
Contact with the exterior leads to contamination of the uterus.
Dystocia
Medical assistance during difficult calving increases the chances of damaging and letting bacteria into the uterus.
Abortions
During an abortion, the cervical canal opens, which allows bacteria into the reproductive system and towards the uterus.
Main causes
Unlike many other infectious diseases, metritis is often caused by several bacteria working together. However, some bacteria can cause metritis on their own, including Arcanobacterium pyogenes and Fusobacterium necrophorum.
Other bacterial species frequently found in postpartum cultures include Escherichia coli, Prevotella melaninogenica, Trueperella pyogenes, Mannheimia haemolytica, Haemophilus somnus, Pseudomonas aeruginosa, and various species of Pasteurella, Staphylococcus, Clostridium and Streptococcus.
Signs and symptoms
On some occasions, the disease is less obvious in cows with subclinical cases of metritis, which is a less visible form of the disease.
In cases of clinical metritis, the signs and symptoms observed vary widely:
- Yellow mucopurulent vaginal secretions, bad odor
- Pale mucous membranas
- Loss of appetite and dehydration
- Fever
- Depression, apathy, lethargy and weakness
- Decreased milk yield
- Decreased fertility
- Increased risk of other diseases, like ketosis and mastitis.
Degrees of the disease
Metritis can be classified by its severity (Sheldon et al, 2019):
Animals with abnormally enlarged uterus and a purulent uterine discharge, but no other symptoms.
Animals with abnormally enlarged uterus and a purulent uterine discharge, plus additional signs of systemic illness such as decreased milk yield and fever.
Animals with abnormally enlarged uterus and a purulent uterine discharge, plus signs of toxemia such as lack of appetite, cold extremities, depression and even collapse.
Financial losses
How to fight metritis
Prevention
There are various strategies to prevent bovine mastitis, including proper calving, good hygiene and cleanliness of facilities, proper nutrition and daily monitoring over the first three weeks postpartum.
These measures, while effective in reducing the incidence of metritis in cattle, do not eliminate it completely.
Diagnosis
The best option is to combine several diagnostic options to catch metritis early. The least invasive method is taking the animal’s temperature rectally and assessing vaginal secretions.
Treatment
When a case of metritis is detected, quickly implementing the right treatment to minimize the consequences is key.
If there is a lot of puss or necrotic tissue, uterotonic agents should be administered to help empty the uterus, followed by an intrauterine antibiotic infusion to treat the infection.
BIBLIOGRAPHY
- Pérez-Báez J, Silva TV, Risco CA, Chebel RC, Cunha F, De Vries A, Santos JEP, Lima FS, Pinedo P, Schuenemann GM, Bicalho RC, Gilbert RO, Rodrigez-Zas S, Seabury CM, Rosa G, Thatcher WW, Galvão KN (2021) The economic cost of metritis in dairy herds. Journal of Dairy Scienc, 104(3):3158-3168. doi: 10.3168/jds.2020-19125.
- Sheldon, Iain. (2019). The Metritis Complex in Cattle. 1016/B978-0-7020-7233-8.00023-9.