What should be done if a cow retains the placenta after calving? Medication should be chosen according to the specific situation

AbstractThere are many treatment methods for postpartum placental retention in cows. Common ones include intrauterine infusion with hydrogen peroxide or 5%-10% hypertonic saline, and subcutaneous or intramuscular injection of oxytocin, estradiol benzoate, etc. The main causes of postpartum placental retention in cows include placental infection and inflammation, weak postpartum uterine contractions, placental aging or immaturity, and placental congestion or edema.

1. Treatment methods for postpartum placental retention in cows

1. Administer motherwort water, 2 times a day for 3 consecutive days; intramuscular injection of oxytocin may also be used.

2. To prevent uterine infection in cows, rinse the cow's uterus with 0.1% rivanol solution during this period.

3. If drug treatment has still shown no effect after two days, surgical manual removal of the placenta must be performed immediately.

4. Intramuscular injection of posterior pituitary extract, or intravenous injection of ergometrine maleate, to promote uterine contractions.

5. Use estradiol benzoate injection, intramuscularly or subcutaneously; after waiting 1 hour, inject oxytocin intramuscularly, and repeat the injection 1 time after 2 hours, thereby promoting uterine contractions.

6. Infuse the uterus with 5%-10% hypertonic saline, or hydrogen peroxide, to separate the placenta, allowing the fetal membranes to detach and be completely expelled.

7. To prevent uterine infection, 1%-1.5% Gongyanqing can be used to rinse the uterus. 8. Cows can be treated sequentially by intravenous injection, 5% glucose and sodium chloride plus gentamicin, dexamethasone; 0.5% iodine solution, 1 gram potassium iodide, 100 milliliters distilled water may also be used, mixed according to proportion to rinse the uterus and the placental membrane spaces, causing the cow's fetal membranes to detach.

2. Preventive measures

During breeding, feed forage rich in calcium and vitamins, strengthen the cow's exercise, and after calving allow the cow to lick dry the mucus on the calf's body by itself. After calving, related drugs can be used to promote recovery of the cow's uterus and expulsion of the fetal membranes, and can also prevent diseases such as endometritis.

2. Main causes of postpartum placental retention in cows

1. Placental inflammation: during pregnancy the uterus is infected with Salmonella, Mycoplasma, molds, Trichomonas, Listeria, fetal Vibrio, Toxoplasma, etc., or the cow has placentitis and endometritis, causing partial proliferation of connective tissue, and adhesion between the calf's fetal membranes and the cow's fetal membranes.

2. Placental tissue structure: the cow's placenta is a mixed placenta of epithelial chorion and connective tissue chorion; the close connection between the calf's fetal membranes and the cow's fetal membranes is also one of the causes of postpartum placental retention in cows.

3. Weak postpartum uterine contractions: the main cause of this situation is that the fed forage is too monotonous, resulting in malnutrition in the cow, thus lacking phosphorus, calcium, selenium, vitamin A, vitamin E, etc.; in addition, emaciation or overweight, older age, weak constitution, oversized fetus, insufficient exercise, etc. can all trigger postpartum placental retention in cows. Secondly, a long labor process, excessive fetal fluids, premature birth, miscarriage, parturient paralysis, uterine muscle fatigue, failure to nurse the calf in time, etc., cause insufficient release of oxytocin, which also affects detachment of the fetal membranes from the uterine muscle.

4. Placental aging or immaturity: placental aging occurs mainly due to proliferation of connective tissue in the cow's placenta and thickening of the surface tissue of the maternal cotyledon, so that the chorionic villi become clamped within the glandular crypts; endocrine secretion gradually weakens, and the fetal membranes are not easy to detach. In immature fetal membranes, the collagen fibers of the maternal cotyledon are wavy and the outline is relatively clear, so the fetal membranes are very difficult to separate. Generally, the earlier the premature birth, the higher the incidence of placental retention.

5. Placental congestion or edema: during the birthing process, strong contractions of the cow's uterus or too-rapid closure of the umbilical blood vessels can both trigger placental congestion, causing the chorionic villi to become clamped within the glandular crypts, and can also cause edema of the glandular crypts and villi, making it difficult for blood in the villi to be discharged. Placental edema can extend to the tail of the villi, so that the pressure in the glandular crypts cannot decrease, and the placental tissue remains tightly connected, thus preventing the cow's fetal membranes from being expelled.