PREFOALING AND FOALING CONSIDERATIONS
Last spring, some of you successfully bred mares and have been waiting almost a whole year for a live, healthy foal to be born. Here are some tips to help you achieve your goal.
The normal gestational length for mares is 324 to 371 days, with most foaling between 325 and 343 days. Some foals born between 300 and 320 days may be viable, but are often weak and more susceptible to infection.
You should perform deworming every eight weeks throughout pregnancy. The mare should be de-wormed 30 days before parturition, and again several days after foaling. Pnuemabort-KR should be given at three, five, seven, and nine months of gestation to help prevent abortion.
Approximately 4-6 weeks before foaling, mares should be vaccinated for influenza, rhinopneumonitis, tetanus toxoid, Eastern/Western equine encephalitis, and strangles to increase the antibody levels in the colostrum, or first milk. Foals, unlike humans, are born without antibodies, and must ingest colostrum to help protect them from disease.
If a Caslick has been placed, it should be opened at least one week before the mare is due to foal. Observe the mare for udder development and leaking of the sticky, yellow-tan colostrum. If leaking occurs, colostrum should be collected in a clean, plastic container and frozen until foaling.
Fortunately, 95% of foalings are normal, and require no human assistance; however, if the mare has been actively straining for more than 15-20 minutes, immediately call a veterinarian for help. Most dystocias (difficult births) result in the death of the mare, fetus, or both, making early recognition and correction imperative.
The mare has three stages of labor. Stage I lasts from 30 minutes to four hours, although the mare has control at this point, and can delay foaling for 1-2 days. She will exhibit signs very similar to colic: restlessness, looking at her flank, swishing her tail, getting up and down, and sweating.
Stage II labor should result in the expulsion of the fetus within 30 minutes. This is by active abdominal contraction. If a red, velvety sac appears at the vulva, you should immediately rupture this and give assistance for foaling. This structure shows a lack of oxygen to the foal.
The umbilicus should be allowed to rupture on its own, leaving 1-2 inches of umbilical stump from the foal’s abdomen. It should be observed for hemorrhage, urine leakage, or swelling at birth and for several days following birth. Use iodine (1-2%) or chlorhexidine (NolvasanR) daily for 3-4 days to disinfect the stump. You may also give a commercial enema (be very gentle) to help prevent meconium impaction.
Stage III, or expulsion of the placenta, should occur within three hours, or assistance will be required for its removal before infection begins. Laminitis, metritis, or peritonitis can occur secondarily to a retained placenta. The placenta should be saved for veterinary inspection to help determine any health risks to the mare or foal. Having every mare examined post foaling for uterine/vaginal tears is advisable. Your mare should be infused at least twice to increase the chances of a successful breeding during the first or second heat cycles. Your foal should be examined for congenital defects and other illnesses, and blood should be taken to determine antibody levels.
Beginning at one month of age, the foal should be de-wormed monthly until 12 months old. Vaccination for influenza, rhinopneumonitis, tetanus toxoid, Eastern/Western equine encephalitis, and strangles should be done at monthly intervals for two to three months.