Normal Maternal-Foal Behavior
Key aspects of normal equine maternal behavior include (1) attending to the foal within seconds after delivery, including nuzzling, licking, and vocalization, (2) avoiding walking or lying on the neonate, (3) allowing and facilitating nursing of own, but not other foals, and (4) protecting the neonate from intruders by positioning herself between the neonate and intruders, and even attacking or driving away intruders. Interactive bonding behavior occurs between the neonate and dam beginning at parturition and continuing for the first day or two until the selective bond is established. The foal plays an active role in eliciting maternal behavior and bonding. Even before standing, the foal reaches the head and neck to nudge and nose the dam. The foal vocalizes and responds to the vocalizations of the dam, even before standing. After standing the foal seeks the udder. Once on its feet and nursing the foal actively lingers near and returns to the mare if separated.
Abnormal Maternal-Foal Behavior
Inadequate or abnormal mothering behavior and bonding of mares and foals is a relatively rare, yet very urgent problem. The etiology of such behavior and the most efficient course of intervention or therapy for the various types of problems continue to be subjects of controversy. In general, problems are more common among first-time mothers, and some types of problems may recur with subsequent foals. The abnormal behavior usually occurs immediately after parturition but in some cases may emerge after 1 or several days of normal behavior. The important task is to determine the specific nature of the problem while maintaining the safety and strength of the foal and the potential for maintaining the bond.
At least six distinct categories of inadequate or aberrant behavior have been identified in mares. The simplest type is ambivalence with a lack of attention and protection or bonding to the foal. This is most commonly found with sick, weak, or medicated mares and/or foals, or in mares and foals separated or overmanipulated during the periparturient period. Normal maternal-foal interaction may commence as the strength of one or the other returns. In cases in which a decision is made to try to revive the bond, it is best to keep the animals together with minimal disturbance necessary for the supportive health care.
Excessive aggression toward humans or other animals seems to be related to extreme protectiveness of the foal. Although strong maternal protectiveness in free-running conditions may be celebrated, in the domestic situation it actually can lead to injury of the foal. While rushing to interpose herself between the foal and perceived threat, the mare may trample or push the foal into human-made obstacles in confined conditions. The intensity of such protectiveness typically subsides within a few days but may persist through weaning in rare cases.
Management aimed at avoiding evoking protectiveness when the foal is in a position where it might be trampled, coupled with deliberate training of the mare to accept necessary intruders, usually are adequate solutions. Injuries to the young foal may be less likely when in a large stall or paddock than if in a small stall. Even when directly witnessed, protective behavior can be easily misinterpreted as attack of the foal. In open spaces, these mares rarely injure the foal, so moving the pair from a box stall to a large paddock may facilitate diagnosis. Overprotective mares tend to become even more so with subsequent foals. They often do best if allowed to foal under pasture conditions rather than in a confined foaling stall.
Some mares fear the foal as if it were an intruder. In such mares, normal bonding and protective behavior seem displaced by an urgency to escape from the foal, as they would in instances of fear of a pig or llama. Most of these can become tolerant with systematic desensitization (gradual introduction with reassurance and reward) as would be done for any feared novel object or situation.
Avoidance of the foal or aggression that is clearly limited to nursing typically, but not always, occurs with obvious udder edema and sensitivity to tactile stimulation. Positive bonding behavior and protectiveness may remain normal. For nursing avoidance or mild aggression, nursing supervision with physical restraint of the mare under halter and/or in a nursing chute in general seems to work better than tranquilization. Phenothiazine-based tranquilizers, reserpine (up to 4 mg), and benzodiazepine derivatives are possible treatments, but precautions must be taken to avoid adverse effects on the nursing foal.
Savage attack, a fifth type of maternal behavior problem is relatively rare but usually life threatening to the foal. The most common scenario is a sudden offensive attack, with lowered head and opened mouth biting or grasping the withers, neck, or back of the foal. The dam may lift, shake, and toss the foal against an object or stamp and hold it to the ground. In contrast to foals injured by overprotective mares, fearful mares, or mares resisting nursing, savagely attacked foals usually have bite wounds and serious multiple skeletal injuries. The only recommended practical long-term solution is permanent separation of the mare and foal. Savage attack often follows one or more days of apparently normal acceptance, bonding behavior, protection, and nursing of the foal, and it usually repeats if the mare and foal are not separated. It is for this reason that supervision, restraint, and tranquilization are rarely practical solutions to savage attack. Savage attack of foals usually repeats with subsequent foals. A nurse mare when available is the recommended best alternate rearing situation for foals. The window of opportunity for fostering varies among mares, but usually best results are obtained with both mare acceptance and foal bonding to the mare within 3 days of parturition. The hide, blanket, fetal membranes, or feces from the biologic foal can be used to mask the “foreign odor” of the foster foal.
In busy breeding areas, breeder networks connect orphans and rejected foals with potential nurse mares (mares that have lost a foal). Also some farms that specialize in preparing “professional” nurse mares for lease to farms with orphan foals. Hand-feeding in isolation from other foals or horses is not a generally successful strategy because behavioral maladjustments in the form of inadequate socialization with horses and overattachment to humans usually ensue. Tub-fed kindergartens of several foals housed together with minimal human contact generally have good physical and social development outcomes.
Adoption or stealing of the foals from other mares usually occurs during the thief mare’s periparturient period. Upon foaling of her own neonate, the thief mare may abandon the stolen foal, which may not be reaccepted by its original dam. This is probably the most rare type of maternal behavior problem in horses, most commonly seen under unusual management conditions, such as induction of parturition in a large number of closely confined mares.