After patiently waiting to meet your home-bred foal through an 11-month gestation period, it is natural to want the very best for his wellbeing.
His dam provides comfort, nutrition and education at the start of his life. There comes a time, however, when the foal has to be weaned. This separation allows the foal to be readied for activities without his dam and ensures that the maternal bond is broken before he starts his education.
Under natural conditions, foals suck from their dams until they are approaching a year in age, at which point the dam is preparing to foal again. The offspring stay with their mothers within the herd until they reach reproductive maturity, when they join a new group.
Most domesticated horses are weaned suddenly, and much earlier than this — at between four and six months of age. A horse’s temperament is thought to be affected by environmental stimuli until he reaches eight months of age, however, which prompts the suggestion that we are weaning our foals too young.
Whatever the time-frame chosen, the separation process should be as stress-free as possible for the future health of both mare and foal.
At weaning, metabolic and hormonal changes are observed as a physical separation breaks the maternal provision of emotional, physical and nutritional support. To reduce the negative impact, familiarisation to this separation is beneficial — starting between four and six weeks before mare and foal part company for good.
Progressive weaning is ideally performed in groups, so the offspring are with familiar individuals of a similar age. The foals are separated from their dams for increasing amounts of time each day, on the other side of a physical barrier such as a fence. This prevents the foal from suckling but allows olfactory and tactile contact as he can still see, smell and nuzzle his dam.
Foals are more confident, easier to handle and more inclined to explore in the first few months post-weaning if they have undergone this gradual introduction to separation.
When a foal is weaned under stressful circumstances, resulting in a premature and complete separation, his personality can be affected into adulthood. Behavioural changes can be associated with a decrease in food intake, resulting in loss of condition and a reduced growth rate — which can have a significant effect on the foal’s commercial value.
An increase in cortisol, a hormone associated with stress, can also result in a decrease in the activity of osteoblast cells, which create new bone, resulting in poor bone mineralisation and an increased risk of developmental bone disease. Weaning at a minimum of four and a half months of age will minimise the possibility of such problems.
Mare’s milk alone does not provide enough energy for the demands of a four-month-old foal. Introducing creep feed alongside quality forage prior to weaning ensures the foal’s nutritional requirements are met for optimal growth. This also reduces some stress of weaning, as he is already familiar with the feedstuff.
While the amount of feed required varies according to the manufacturer’s advice, a daily allowance of 0.45kg per month of age is a rough guide. A foal’s gastrointestinal tract will develop to become more efficient between six and 12 months of age, thought to be due to the increased energy demand associated with growth.
The mare is most prone to mastitis during the immediate post-weaning period, as her teats remain open but the mammary glands are not being physically flushed out as the foal nurses. Feeding her fewer concentrates in the week leading up to weaning will reduce her milk production, in preparation. Monitor her mammary glands in the initial post-weaning period for signs of pain and inflammation, and seek veterinary advice if this is evident.
Prior to complete weaning, the youngster should be paired up with a buddy of similar age and size and the same sex. The two foals can then be kept, along with their dams, in a secure stable or paddock.
Once the management routine has been standardised for several days, the mares are taken away to pasture or stabling — out of sight and sound of the foals. The mares should also be in familiar pairs or groups, to reduce the anxiety involved with the separation.
The foal pair can then be turned out in a group with other pairs. Introducing new, same-age individuals will heighten social tension and increase stress levels. Ideally, these introductions are made before the weaning process so bonds can be formed.
It has been demonstrated that unfamiliar, unrelated adult horses can provide social support to newly weaned foals. Retired horses used as “nannies” can have a calming influence.
Behavioural changes in both the dams and their offspring may be evident, however, including an increased frequency of vocalisation, reduced time resting and, in the weanlings, a greater wariness of humans and novel stimuli.
Cortisol has been shown to rise at weaning and stay elevated for a month after. This is often coupled with suppression of the immune system as white blood cell values alter and display a stress response.
Studies have demonstrated that the cortisol levels of both dams and foals rise — irrespective of the weaning method — but that the increase is lower in those that have been progressively weaned than those suddenly separated. Behaviour differences between the groups were still evident three months after weaning, with the suddenly weaned foals remaining more fearful and less predictable.
Because of the immune function impairment, avoid stress-associated procedures such as regrouping, castration, vaccination or de-worming within a month either side of weaning. Influenza and tetanus vaccinations should be started from five months old, however, so consider timing carefully. Vaccinating a foal at the point of weaning can heighten the risk of a snotty nose and enlarged lymph nodes.
While progressive weaning may not be an easy option due to the time and additional labour, it should be implemented where possible. The benefits will last through the foal’s adolescence and beyond, potentially shaping his personality for life.
Ref Horse & Hound; 5 September 2019