- Hypocalcemia (Eclampsia)
- Uterine Prolapse
- Subinvolution of Placental Site
- Test your understanding
1) What does a normal bitch look like in the days following whelping? When should I worry that something’s wrong?
Normal bitches pass an odorless, reddish brown to green vulvar discharge for up to 3 weeks after whelping. Body temperature may be slightly elevated for a couple of days but never should be above 102.5° F. The mammary glands should be full but not painful. It is normal to see milk expressed from several openings at the end of every nipple. Abnormalities include creamy, malodorous vulvar discharge; one or more swollen and painful mammary glands; decreased appetite and thirst; disorientation; and neglect of the pups.
2) My bitch finished whelping in the “wee hours” of the morning. Does she need to go into the veterinarian for a “cleanout” shot?
Not if she has live pups that are nursing. The nursing pups stimulate frequent release of small amounts of oxytocin, which causes milk letdown and uterine contractions. This is better for the bitch than our giving her one big shot of oxytocin.
The puerperal period is that time from whelping to complete involution and repair of the uterus. This period usually lasts about 12 weeks. By the end of the puerperal period, the pups are weaned, the uterus is normal sized, all placental sites are repaired, and the bitch should have regained normal body condition.
It is normal for a bitch to pass an odorless vulvar discharge for up to 3 weeks after whelping. This discharge, called lochia, may vary in color from blood-tinged to green to brown and should decrease in volume over time. Some breeders like to take the bitch to their veterinarian for an injection of oxytocin after whelping. It is not necessary for bitches to get a “cleanout” shot of oxy-tocin after whelping, especially if there are nursing puppies. The pups are stimulating frequent release of small amounts of oxytocin.
The bitch’s rectal temperature may be slightly elevated for several days after whelping as her uterus undergoes repair and her mammary glands are actively distended and manipulated during nursing. The rectal temperature never should be higher than 102.5° F and should return to the normal range of 99° to 101°F by 3 days after whelping.
Hypocalcemia, or eclampsia, is a low concentration of calcium in the body. Another name for this condition is puerperal tetany. This condition should not be confused with preeclampsia in women, a syndrome of high blood pressure and protein loss that occurs during pregnancy. Eclampsia in dogs occurs most commonly in small-breed dogs nursing a large litter. Onset of clinical signs is most common at peak lactation, 2 to 3 weeks after whelping, when the demand for calcium for milk production outstrips the bitch’s ability to draw calcium from her bones.
Breeds described in the literature as predisposed to eclampsia include the Chihuahua, miniature pinscher, shih tzu, miniature poodle, Mexican hairless, and Pomeranian. In general, occurrence is more likely if the ratio of body weight to litter size is small.
History and clinical signs
Although the onset of clinical signs of eclampsia is most common at peak lactation, hypocalcemia may develop during pregnancy or at whelping. Initial clinical signs include neglect of the pups, restlessness, and scratching at the face. There is quick progression to wobbly gait, dilated pupils, disorientation, and muscle tremors. In the final stages, seizures and stiff paralysis are seen. In a report of 31 cases of eclampsia in dogs, six dogs did not show this classic progression of signs.
Tentative diagnosis is made based on the signalment and history. Definitive diagnosis requires identification of low calcium concentrations in blood.
Calcium is administered intravenously to effect. The heart must be evaluated throughout administration of calcium, preferably with an electrocardiogram (ECG). If calcium is infused too quickly, arrhythmias and abnormalities in heart rate may be induced. Once the dog is stabilized, calcium also can be infused subcutaneously. It is important to use calcium solutions appropriate for the route of administration; some calcium solutions are irritating and will cause loss of the skin over a site of subcutaneous administration. Once the dog can be sent home, oral calcium and vitamin D should be administered for the duration of the lactation. It may be beneficial to take the pups off the bitch for 12 to 24 hours. If clinical signs of eclampsia recur when the pups resume nursing, they must be removed and hand-fed or weaned.
Prognosis depends on the bitch’s response to therapy. Most bitches that respond quickly to calcium therapy recover well.
Eclampsia may recur at subsequent lactations. The best way to prevent this is to feed a well-balanced diet during pregnancy, without calcium supplementation. Administration of calcium supplements during pregnancy shuts down the bitch’s calcium regulatory system; so, when she needs to draw calcium from bone during lactation, her body cannot respond and clinical signs of eclampsia develop. It is much better to wait to supplement calcium orally until at or after whelping.
Uterine prolapse is protrusion of part or all of the uterine horns and body through the vulvar lips. This occurs very uncommonly in dogs as a complication of parturition. The animal may be in shock if loss of blood and fluid associated with the prolapse has been significant. If the tissue is not healthy, it should be surgically removed from the prolapsed position. If the tissue appears normal, repositioning in the abdomen may be attempted; prognosis for future fertility and chance of recurrence are undefined.
Metritis is infection of the uterus. This is not the same as pyometra, which is infection overlying the uterine abnormality termed cystic endometrial hyperplasia (). Metritis occurs when the normal flora of the reproductive tract are allowed to colonize the uterus postpartum. This most commonly occurs following dystocia, retention of a fetus or a placenta, or prolonged delivery.
No age or breed predisposition has been reported for this condition.
History and clinical signs
The bitch neglects the pups and becomes lethargic and inappetent. The vulvar discharge becomes thick, creamy to reddish brown, and malodorous.
Cytology of the discharge permits identification of many unhealthy white blood cells and bacteria. The uterus is often palpably enlarged. Ultrasound may be used to identify retained fetal or placental tissue (). Complete blood count may show elevated white blood count in the general circulation. The occasional bitch is in shock. Samples of vulvar discharge should be submitted for culture.
Appropriate antibiotic therapy is instituted. Some dogs benefit from treatment with prostaglandin, which causes uterine contractions and helps to expel any retained tissues. Some bitches with severe signs of systemic disease require ovariohysterectomy.
Prognosis for future fertility in bitches left intact is very good. If the infection can be eradicated, the underlying uterus is normal.
Subinvolution of Placental Site
As the name implies, subinvolution of placental sites (SIPS) is incomplete healing of the areas of the uterine lining from which placentas pulled away during whelping. The cause of SIPS is not known.
Most commonly, SIPS is seen in dogs whelping their first litter. No breed predisposition has been reported.
History and clinical signs
Most bitches presenting with clinical signs of SIPS had a normal delivery and the pups are doing well. The vulvar discharge maintains the appearance of lochia (serous to slightly blood tinged, odorless) but persists beyond 3 weeks postpartum. The bitch exhibits no other abnormalities.
Definitive diagnosis requires biopsy of the uterine placental sites. This rarely is done. Cytology of the vulvar discharge is performed to differentiate this from metritis. The cytology in dogs with SIPS contains only a few white blood cells. Complete blood count often is performed to ensure the dog is not becoming anemic from blood loss.
Most cases of SIPS resolve spontaneously. Some dogs will exhibit bloody vul-var discharge until the next proestrus. Very occasionally, bitches will hemorrhage significantly and require blood transfusion and ovariohysterectomy as life-saving measures.
Prognosis for future fertility is excellent in most cases. Recurrence after subsequent whelping is uncommon.
Mastitis is infection of the mammary gland. The most common organisms involved are those of the skin; in one study, Staphylococcus aureus was the most common isolate. As puppies nurse and pull at the teats, environmental bacteria can gain entry into the mammary gland.
No age or breed predisposition has been reported for this condition. Mastitis most commonly occurs in the puerperal period but occasionally occurs during false pregnancy ().
History and clinical signs
The bitch neglects the pups and may become lethargic and inappetent. One or more glands may be involved; the affected mammary glands are red, firm, and warm to the touch (). Abscesses may be visible or palpable as bulging, turgid spots over which the skin often is stretched and discolored; rupture may occur (). The milk from affected glands often is serous and discolored.
Diagnosis is by physical examination. Evaluation of milk from the affected glands allows identification of many white blood cells and bacteria. Secretions from the affected glands should be submitted for culture.
Appropriate antibiotic therapy is instituted based on culture results. Penicillins often are chosen as an initial therapy; in one study, penicillins were capable of clearing infection in only 45% of cases. Remember that the nursing pups may get some antibiotic from the bitch through the milk. If abscessation is present, that tissue must be surgically drained and trimmed. The pups can be allowed to nurse off normal glands unless open, draining tissue is present. General nursing care includes twice-daily hot packing and milking out of the affected glands.
Prognosis is good in most cases. The occasional bitch or line of dogs develops mastitis at every lactation, presumably because of some anatomic feature of their mammary glands or teats that allows bacterial invasion more readily.
Agalactia is absence of milk in the mammary glands. True agalactia occurs when there is a failure of milk production. This most commonly occurs in malnourished bitches that are in poor body condition. There is no treatment, and pups should be hand-raised (). A dopamine-blocking drug, dom-peridone, may cause an increase in prolactin secretion with subsequent lactation as a side effect. This is not an approved use of this drug in humans or in dogs. Apparent agalactia may occur when milk is being produced but is not being let down into the mammary gland. Administration of oxytocin as an injection or using an intranasal spray oftentimes resolves the problem within seconds. If the bitch is stressed or has evidence of another puerperal disorder, such as metritis, those conditions should be addressed. Bitches with poor milk production resulting from low concentrations of either prolactin or oxytocin may exhibit poor mothering behavior.
Test your understanding
1) Your bitch whelped 11 pups this morning over an 8-hour span. The last pup was born over an hour after the bitch appeared to be done and was stillborn. You were present for the entire whelping and retrieved only eight placentas. You did not see the bitch eat any. Your breeder friend always gives an injection of oxytocin to clean out bitches after whelping. What are the pros and cons of administration of oxytocin to this bitch?
Pros: Oxytocin administration may help the bitch expel the retained placentas, which may in turn decrease her predisposition to metritis.
Cons: If she has 10 live, nursing pups, they are stimulating oxytocin release every time they suckle. These tiny amounts of oxytocin are more likely to cause effective uterine contractions than is administration of one large dose of oxytocin. If you choose not to give the oxytocin “cleanout shot,” signs of metritis to watch for include neglect of the pups and creamy, malodorous vulvar discharge.
2) Your neighbor breeds beautiful Yorkshire terriers. Her 2-year-old bitch whelped a litter of five pups a week ago. You go over to check on the pups for her at midday and notice the bitch is walking unsteadily and the pups are crying. Is this normal? If not, what condition does she most likely have? Do you need to alert your neighbor, or can this wait until she gets home from work?
This is not normal. The most likely diagnosis is hypocalcemia, or eclampsia. This is most common in small breed dogs nursing a large litter. This is an emergency. Call your neighbor now, and get the dog to a vet as soon as possible.
3) Your 3-year-old bitch whelped a litter 9 days ago. When you examine and weigh the pups this morning, you note that the pups have not gained weight and are crying incessantly. The bitch refuses to let them nurse. Her mammary glands are swollen, red, and hot. Your veterinarian diagnoses mastitis and recommends antibiotic therapy. What are the things to consider regarding antibiotic therapy in this bitch?
- Mastitis usually is due to a bacterial infection and so responds readily to antibiotic therapy. The inflamed glands have an increased blood supply, so medications move into them well.
- The antibiotic should be chosen based on culture and sensitivity of fluid expressed from the affected gland(s).
- The antibiotic chosen must be safe for pups because some will be excreted into the milk.
Selections from the book: “The Dog Breeder’s Guide to Successful Breeding and Health Management”, 2006.