28 NOVEMBER NOVEMBRE 2009

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1 BELGIAN EQUINE PRACTITIONERS SOCIETY (BEPS) XXVI de XXVI ème 28 NOVEMBER NOVEMBRE 2009 Met de medewerking van Avec la collaboration de Auditorium BMW Auditoire BMW UZ LEUVEN CHU Leuven Herestraat 49 Herestraat Leuven 3000 Leuven

2 INDUCTION OF LACTATION AND ADOPTION OF AN ORPHAN FOAL Dr. Peter DAELS Keros Equine Insemination and Embryo Transfer Center Westrozebekestraat 23A, 8980 Passendale, Belgium Introduction When facing an orphan foal due to the death of the mare or unwillingness to accept her foal, it is critical to quickly find an alternative to feed the foal and create a suitable social environment for the upbringing of the foal. With some luck we can sometimes find a mare that has recently lost her own foal and that will adopt the foal as her own. When a suitable adoption mare cannot be found, other options must be considered including feeding a replacement formula using a bottle or bucket. Today, there are excellent milk replacements on the market that enable us to feed an orphan foal up to weaning age with excellent body development. However, prolonged bottle feeding often results in poor social skills towards other horses and abnormal/dangerous behaviour towards humans. This behaviour may interfere with the normal handling of the horse and the training of the horse as an adult. Some bottle-reared horses are unsuitable even dangerous for normal equitation. Because of these behavioural problems we recommend very strongly to place any orphan foal in a situation where it is reared together with other horses. In the absence of a traditional adoption mare (lactating mare that has recently lost her own foal) one can induce milk production in a non-parturient mare. Several dopamine-d2-antagonists (domperidone and sulpiride) have been used to increase endogenous prolactin secretion in mares. These treatments are used to either advance the onset of reproductive activity in anestrous mares in early spring or to counter the ill effects of fescue toxicosis in pregnant mares at term 3. Lactation can be induced in non-parturient mares that have foaled in previous years using a treatment that includes estrogen, progesterone and a dopamine D2 antagonist (sulpiride or domperidone) 1-5. The results of these studies clearly indicated that lactation can be induced in mares and that milk production continues when frequently milked (see Figure 1). Belgian Equine Practioners Society (BEPS) LEUVEN, Belgium, 28 th November

Figure 1: Milk production during (blue zone) and following sulpiride administration 1. Mares were milked 6 x/day. Note that milk production after the end of treatment remains constant.

3 Figure 1: Milk production during (blue zone) and following sulpiride administration 1. Mares were milked 6 x/day. Note that milk production after the end of treatment remains constant. The quality of the milk produced is similar to a normal post-parturient lactation 1,2. Several attempts have been made to induce the production of colostrum but so far results have been disappointing (personal observations). Progesterone and/or estrogen are essential for the induction since sulpiride only does not induce lactation in ovariectomized mares 4. However, field experience suggests that in mares with normal ovarian activity, progesterone and estrogen administration is not necessary. Mares with an induced lactation are able to adopt a foal and to develop a maternal bond that is similar to foaling mares 6. Careful observation of the behaviour in normal mare-foal combinations and in adopted combinations does not reveal any difference in the recognition and interaction between mare and foal 6. This mare-foal bond makes it possible to raise the orphan foal in a normal social environment and develop the social and learning skills of a normal foal. Over the years, we have developed a simplified, abbreviated protocol for the induction of lactation and we have also greatly simplified the adoption method. Induction of Milk Production Selection of Mares - Mares must have foaled and nursed a foal at least once in their life. Mares that have raised several foals tend to have a better milk production and display a more predictable maternal behaviour. Mares must be in good body condition, free of disease and mammary abnormalities, gentle and calm. Belgian Equine Practioners Society (BEPS) LEUVEN, Belgium, 28 th November

4 Hormonal Treatment Protocol 1 On the first day, the mare receives a single intramuscular injection of estradiol-benzoate (50 mg/500 kg mare) and she is started on daily altrenogest administration (22 mg q 24h IM) and twice-a-day injections of sulpiride (1 mg/kg q 12 h IM). Sulpiride is available in an aqueous solution for injection for human use (Dogmatil, Sanofi, ampulles 100mg/2ml). When the mammary gland is significantly increased in size, has a filled appearance and/or milk drops are present at the teat, milking can be started, generally after 4 to 7 days of treatment. Once milking has started, it is important to continue milking 5-7 times per day. Keep in mind that mares have very limited storage capacity and that foals nurse at min intervals. Infrequent milking and accumulation of milk in the mammary gland tend to cause a drying-up effect. Protocol 2 On the first day, the mare receives a single administration of dinoprost (5 mg IM), and she is started on twice-a-day injections of sulpiride (1 mg/kg q 12 h IM). Milking - Milking can be done by hand. The majority of mares adjust to these manipulations without much resistance. Mares that continue to resist should be considered poor candidates for adoption. For optimal milk letdown and fast milking, administer oxytocine (5 IU IM) 1-2 minute before milking. Duration of Treatment - After 3-4 days of milking, production should have reached 3-5 litres per day for a 500 kg horse. At this point, the mare is ready for adoption. In our hands, mares that are not producing a significant amount of milk on day 7 (< 3 litres) are not suitable adoption candidates. Altrenogest treatment is generally stopped on Day 7 and sulpiride treatment is continued until several days after adoption is completed. Continuation of treatment for more than 7 days after adoption is likely inefficient because the effect of these dopamine antagonists on prolactin secretion tends to decrease over time. Adoption Technique Environment and confinement of the adopting mare The best location for the adoption is a closed stall with no contact with neighbouring horses. In our hands, a simple metal pipe placed at the level of the hip of the mare and solidly attached to both lateral walls of the stall offers the best set-up for a safe adoption attempt (Figure 2). Belgian Equine Practioners Society (BEPS) LEUVEN, Belgium, 28 th November

5 Figure 2. Adopting mare placed behind contention pipe in back of stall. The metal pipe covered with a rubber lining is placed at the height of the hip of the mare to give the foal ample space to reach under the pipe. The pipe is attached with a sliding rail to adjust the height. A solid ring is fixed to the back wall to limit the mare s head. Introduction of the foal - Several experiments were conducted to investigate the most efficient system for adoption. The discipline method - Welch pony mares were placed in an individual stall and confined behind a horizontal pipe placed at chest height (Fig 1). The newborn foal was removed from its natural mother at birth and presented immediately to the adoptive mare. Mares were disciplined if they responded aggressively to the foal. The vaginal stimulation method This method, adapted from ewes, oxytocin release in the brain is activated via the Ferguson's reflex by massaging the vagina and cervix of the mare. The foal was held close to the mare s head while the mare received vaginal-cervical stimulation. The stimulation consisted of a vigorous massage of the external portion of the cervix and some attempt to dilate the cervix. This stimulation was applied during 2 min twice at 10 min interval. During and after the stimulation the foal was held at close proximity of the head and shoulder of the mare to allow the mare to sniff and lick the back the buttocks of the foal. Belgian Equine Practioners Society (BEPS) LEUVEN, Belgium, 28 th November

6 Comparison between these two methods - Adoption took significantly longer for the mares that did not receive vaginal-cervical stimulation than for mares that received the vaginal-cervical stimulation. 14 out 16 mares that received vaginal-cervical stimulation adopted the foal immediately and maternal behaviour occurred immediately. In the mares that did not undergo vaginal-cervical stimulation, only 2 mares adopted immediately and the remaining 14 mares displayed aggressive and potentially harmful action towards the foal for 4 to 24 hours. It is interesting to note that all mares finally adopted the foals and that maternal behaviour was complete and indistinguishable from that of mares that stayed with their own foal 6. Observations demonstrated that the behaviour of adopted and normal nursing mares was identical with regard to recognizing the foal, attachment to the foal and protecting the foal in the herd 6. NEW - Induction of adoption with prostaglandin F2α In this new and simplified protocol, maternal behavior is stimulated through the administration of a large dose of PGF2α. It is presumed that prostaglandin triggers oxytocin release in the brain. At the start of the milk-induction treatment, the adopting mare is placed in a stall adjacent to the orphan foal. The adopting mare must be able to see and smell the foal. The mare receives the lactation induction treatment as described in Protocol 2. As soon as the mammary gland started to enlarge and milk is present, milking is performed manually 5x/day. Adoption is performed when the adopting mare has accepted the presence of the foal in the adjacent stall and has sufficient milk. Once or twice-a-day the foal is taken away, out of the mare s sight and the behavior of the adopting mare is evaluated. A few days into the induction protocol the mares should start to show signs of separation anxiety and she will begin to whinny and look for the foal. In general, the adoption is performed when mares has received 5-7 days of treatment. Maternal behavior is not induced by vaginal massage but by a single injection of PGF2α (cloprostenol, IM, 2 to 3ml Estrumate, Shering-Plough). The foal is moved away from the mare and the mare receives an injection of PGF2α. After a few minutes when the mare is starting to sweat and show other PGF2α-induced side-effects such as restlessness and colic symptoms, the foal is moved to the mare's stall and allowed to nurse. The foal should be encouraged to nurse the mare during the phase of PGF2α-induced side-effects. When doing so, the mare usually starts to lick and nuzzle the foal. During this time, the foal is encouraged to continue to nurse the foal and the mare is restrained sufficiently to allow the foal to nurse but not limit the mare licking and smelling the foal. Maternal behavior is activated when the mare follows the foal around the stall, vocalizes to communicate with the foal and licks the foal. When the maternal behaviour is established, both mare and foal can circulate freely in the stall and continue the bonding process. Complete adoption of the foal by the mare is usually accomplished within minutes after introduction of the foal. Growth of the foals In the initial studies, sulpiride treatment was ended two days after adoption and mares and foals were turned out in pasture. Under these (experimental) conditions, a significant delay Belgian Equine Practioners Society (BEPS) LEUVEN, Belgium, 28 th November

7 in weight gain between adopted and control foals was seen in the first two weeks and in some foals also in the second two weeks. However, at weaning age there was no difference in bodyweight between the adopted and control foals. While foals lacked in body weight in the first two weeks, they appeared alert and growing normally (subjective observation). In our commercial setting, we recommend that sulpiride treatment is continued for 7-10 days after adoption. It is not useful to continue sulpiride treatment beyond 20 days (total duration) because we and others have observed a decreasing effect over time on prolactin secretion. All client-owned foals are supplemented with artificial milk 3-5 times per day (1-2 liters each time) for 3 to 15 days. Bottle feeding is continued until the foal refuses the artificial milk or when it was judged that the mare produced sufficient milk. Although, we were never able to neither quantify the weight gain in these foals nor evaluate objectively the impact of these interventions, we noted a very high client satisfaction rate. References 1. Chavatte-Palmer P, Arnaud G., Duvaux-Ponter C, et al. Quantitative and qualitative assessment of milk production after pharmaceutical induction after pharmaceutical induction of lactation in the mare. J Vet Intern Med 2002;16: Chavatte-Palmer P, Daels PF, Arnaud G, et al. Quantitative and qualitative assessment of milk production after pharmaceutical induction of lactation in mares in Proceedings. Symposium on Equine Reproduction and Annual Meeting of the Society for Theriogenology 2000; Besognet B, Hansen BS, Daels PF. Induction of reproductive function in anestrous mares using a dopamine antagonist. Theriogenology. 1997;47: Guillaume D, Chavatte-Palmer P, Combarnous Y, Duchamp G, Martinat N, Nagy P, Daels PF.Induced lactation with a dopamine antagonist in mares: different responses between ovariectomized and intact mares. Reprod Domest Anim. 2003;38: Daels, PF, Duchamp G, Porter D. Induction of Lactation and Adoption of Foals by Non-Parturient Mares, in Proceedings. Am Assoc Equine Pract 2002;48:68-71 available online at International Veterinary Information Service ( 6. Porter RH, Duchamp G, Nowak R, Daels PF. Induction of maternal behavior in non-parturient adoptive mares. Physiol Behav 2002;77: Steiner JV. How to induce lactation in Non-Pregnant Mares in Proceedings. Am Assoc Equine Pract 2006;528: available online at International Veterinary Information Service ( 8. Daels, P.F. and Bowers-Lepore, J. How to Induce Lactation in a Mare and Make Her Adopt an Orphan Foal: What 5 Years of Experience Have Taught us. In proceedings Am Assoc Equine Pract 2007; available online at International Veterinary Information Service ( Belgian Equine Practioners Society (BEPS) LEUVEN, Belgium, 28 th November

THE AMERICAN QUARTER HORSE RACING JOURNAL

THE AMERICAN QUARTER HORSE RACING JOURNAL Orphan Foal Care Horse owners have many options when faced with an orphaned foal. By Andrea Caudill From The American Quarter Horse Racing Journal library www.americashorsedaily.com