AQHA January / February Magazine AQHA JAN-FEB 2020 PRINT | Page 23

WHAT DO WEANLINGS NEED...
excellent sources of amino acids – so if they are in short-
supply or costly, save them for the weanlings ahead of
any other horses.
Evaluation of growth requires assessment. Regular
monitoring of weight, growth rate and height - using
a measuring-stick, scales and/or ‘condition scoring’ -
are sound practices. Exercise levels also affect growth
and musculo-skeletal development, the final product of
which is gait. Foals allowed free access to pasture have
been shown to travel 16 to 25km each day and to gallop
on average for about 3.5 minutes per 24 hours, divided
into approximately 40 sprints. Exercise restriction,
whether due to injury, mare illness or the environment,
slows development and the diet should be reduced to
provide little energy but meet protein (ie amino acid)
and mineral needs.
The risk of fast, catch-up growth (and hence DOD)
increases after weaning, or a period of restricted
exercise or diet, so it needs to
be managed carefully. Excessive
loading (usually due to excess
body condition), an unbalanced
diet or hard exercise - affect the
pattern of bone growth. Foals
gain 800-1000g per day and we
want this to be bone and muscle,
not fat. After weaning this falls to
an average gain of 0.13kg a day.
It may take several weeks for
weanlings to resume their rapid
growth and this period must be
managed carefully to maintain a slow and steady return
to growth rate. Equally important, loss of the mare’s milk
may reduce the nutrients available for bone formation
during the postweaning period and amino acids and
mineral supply needs to be restored by the feed.
Other benefits of avoiding grain-based and high starch
feeds and supplements are many. The newly weaned
foal is particularly at risk for stomach acidity, early onset
of ulceration and an increased risk for some types of
colic. Slower stomach emptying and more acid-buffering
by oily-fibrous food reduces stomach acid with its
associated discomfort, ulcers and pain. Further down
the intestinal tract in the caecum, fermentation and acid
production from grain-based starch-sugar feeds is linked
to aberrant oral behaviours such as wood-chewing, as
well as some colics and diarrhoeas.
Crib-biting is associated with altered gut-transit time
and gastric ulceration – stomach inflammation and
ulcers were found in 60% of crib-biting foals compared
to 20% of non-crib-biting foals – and they had more
severe ulcers and inflammation upon initial endoscopic
examination. Horses produce saliva (which buffers
stomach acid) only when biting or chewing and its
thought that weanlings wood-chew or crib-bite in an
attempt to stimulate additional saliva production.
Feeding 3-4 small feeds each day and providing a mix
of hay and roughage types (include different hays, beet
pulp, haylage and palatable, non-toxic branches and
leaves where possible) increases feeding/chewing time
and decreases weaving and nibbling behaviours.
The most common problems with nutrition of foals and
weanlings are from insufficient roughage and chewing;
over or under feeding; sharp increases in rates of gain,
and amino acid and mineral imbalances. The bottom line
is to reach a happy medium – not too fat and not too thin.
You don’t want to see ribs but you do want to be able to
feel them. So keep it simple by providing an oil-enriched
vitamin, mineral and amino acid supplement. Free 24
hour access to roughage (pasture/hay) significantly
reduces the occurrence of stomach ulcers in weanlings
and vitamin E is important for immunity. With the
exception of the neonatal period, foals are at their most
vulnerable in the period after weaning. The immunity
they received from the mare’s colostrum has waned and
their own immune system hasn’t begun to reach peak
efficiency. Vitamin E supplementation has been shown
to increase both the killing-capacity of white blood cells
and the immune response to vaccination.
Limit or better still, eliminate grains and grains-based
feeds from their diet – remembering that feeds
containing grain by-products such as millrun, pollard,
bran, hominy meal etc can have dangerously high levels
of starch.
JANUARY/FEBRUARY ISSUE 2020
PG.21