Retained placentas is one health problem all producers face every spring. The resulting metritis (uterine infection) and subsequent infertility can have a large economic impact. A placenta is considered retained if not expelled after 24 hours.
Infertility related to retained placentas results from the infection not being cleared and the cow either conceiving later or being totally infertile. Both reduce the dollar return to the producer in subsequent years.
Retained placentas are worth paying attention to even though beef cows seldom appear sick. One common indicator is a decrease in milk production for her suckling calf or calves. Ideally you need to prevent placental retention as much as possible and when it does occur have a definite treatment protocol.
Nutritionally several key components have been identified. Adequate vitamin A levels (20,000-30,000 I.U./cow/daily), Se (selenium) five mg/cow/day and adequate calcium and phosphorus balances have all been shown to improve dropping of fetal membranes.
Producers should also keep cows in adequate shape with a body condition score of 3 to 3.5 at calving. Cows that are either too fat or especially thin cows have a greater incidence of retained placentas. When calculating mineral consumption of Se it is best you assume nothing is added from the feed since most of Western Canada is deficient in this mineral.
Difficult calving will increase retained placentas so try and select breeding bulls carefully. If you do need to intervene in calving, clean up the vulvar area thoroughly and always use obstetrical gloves. The gloves keep you protected but more importantly prevents contamination of the uterus with undesirable bacteria. Use recommended, non-irritating surgical soap when cleaning the vulvar and vaginal area.
Cows that produce twins and/or that abort calves also have a much higher incidence of placental retention. Even though nutrition can be adequate, twins often have a week to 10-day earlier gestation. This immaturity often does not allow release of the placenta. Cows which produce twins are at a far greater risk of coming up open in the fall.
Follow the protocol for treating retained placentas on all cows that twin. Some herds especially with exotic genetics such as Simmental or Charolais can experience twinning in the order of eight per cent. Cows that do twin are very likely to repeat.
Among cows that have aborted, if they are to be shipped, then treatment for retained placentas is not critical unless the animal becomes sick. Cows should have calved and shed their membranes at least 10 days before slaughter. If abortions are greater than two to three per cent ask your veterinarian to investigate the cause.
Treatment of retained placentas consists of a combination of hormonal and/or antibiotic therapy. Under NO circumstances should you manually remove them. Numerous studies have proven this is more harmful and days to next conception are greatly increased. Years ago this was a big part of a veterinarian’s job (manual removal of retained placentas) but none will advocate doing it any more.
Metritis or uterine infection can result from cows not cleaning and make a cow extremely sick and febrile (feverish).
The uterine discharge is often very watery and foul smelling. This is where your veterinarian may advise flushing the uterus with copious amounts of water and disinfectant. Systemic antibiotics are also administered. Penicillin or tetracyclines are the ones commonly prescribed. There is one approved intrauterine infusion called metricure that has been developed to use intrauterine for endometritis.
Hormonal therapy involves a two-stage approach and the protocol may vary considerably between veterinarians. For cows with twins, difficult calvings, malpresentations or a past history of retention, oxytocin (1-2 cc) can be administered several times every 30 minutes within three hours of calving. After 24 hours with a retained placenta an estrogenic hormone estradiol proprionate (“estrus”) is commonly prescribed by many veterinarians. This is only given once and helps keep the cervix open not trapping the membranes within the uterus itself. Antibiotics instilled into the uterus are often detrimental. They keep the uterus too healthy and the placental membranes remain longer.
Gonadotrophin releasing hormone or GNRH (trade names fertagyl, fertilene, factrel or cystorelin) is very beneficial to give 14 days postpartum on all cows, which were observed with retained placenta or had difficult calvings. The dosage is commonly 100 ug and this drug will achieve an earlier first ovulation. Cycling is a cleansing process so the quicker cows begin cycling the healthier the uterus becomes. In the dairy industry one study where this hormone was given to all cows resulted in a 45-day reduction in days open. While hormones can be effective, check with your veterinarian before using these products.
Any cows seen straining or with discharge on their tails may have developed chronic endometritis. These cows need to be palpated by your veterinarian. The veterinarian may infuse them (metricure or other recommended antibiotic) and administer a prostaglandin to evacuate the uterus of the debris. Prostaglandins especially if administered 21 days postpartum are as effective as antibiotics in treating uterine infection. If the cow comes into heat the cervix opens and the uterine tone forces out a lot of the pus and debris.
By being extra diligent with retained placentas the herds open and late pregnancy rate should improve remarkably. Reproduction is still the biggest reason for culling so lets work to reduce it. Since BSE, a lot of the individual cow medicine was ignored but paying attention to nutrition including trace minerals and maintaining proper body condition scores should minimize retained placentas. All or most of these mentioned hormones are prescription drugs and must be purchased under the guidance of your veterinarian. Fine-tune a program that best suits your management operation and lets minimize the open rate come next fall. We need every cow we can keep in the Canadian herd and prices should remain high for their calves. Individual cows are well worth proper care and treatment.