Page 97 - Hand rearing birds second

Ratites 81

Nutritional­Deficiencies
A wide range of nutritional deficiencies have been suggested to occur in ratite chicks; however,
these are often based on clinical signs that might be seen in domestic poultry rather than actual
knowledge of the conditions as they occur in ratites. Classic and phosphorus‐deficient (particu-
larly in rheas) rickets, vitamin E/selenium‐responsive myopathy, and suspect vitamin B deficiency
syndromes – including dermatitis and curled toes – have been identified in ratites. Some ostrich
chick management protocols include injection with a vitamin E/selenium product shortly after
hatch. Recently hatched emu chicks with twisted necks or that “tumble” and roll may respond to
vitamin B supplementation.

Leg­Deformities

Long‐bone deformity is probably the most widespread problem in young chicks. A number of
interrelated factors are likely involved in the development of this condition. These include over-
feeding (excessive calorie intake) or excess dietary protein leading to too rapid growth, nutritional
deficiencies and imbalances (e.g. calcium, phosphorus, vitamin D, vitamin E, selenium, methio-
nine, choline, manganese, zinc), damage to the leg during hatching or within the hatcher, inad-
equate exercise, and genetic predisposition. The extremely rapid growth rate of ratite chicks
exacerbates any nutritional imbalances that may be present. The most successful methods for
prevention appear to be providing large pens to encourage exercise, reducing the protein level of
the chick diet to under 20% within approximately 2 weeks of hatching, and reducing the total
amount fed.
Leg deviations may be rotational – that is, around the axis of the bone – or to the side. The result-
ing turnout of the lower leg and foot can be severe enough to completely prevent the bird from
standing or walking. The tibiotarsal bone is most frequently affected, but not all cases are alike.
Because of the rapid growth rates, problems may literally appear overnight and can progress rap-
idly. Lateral displacement of the gastrocnemius and other tendons can occur either at the same
time, or secondarily. A variety of splinting and surgical procedures have been attempted, with
almost uniformly poor results unless the leg is splinted correctly within a few hours of the onset of
the problem.
A separate problem seen in ostrich chicks is rotation of the large toe. This problem usually
responds well if corrective splints are immediately applied. Again, a variety of causes have been
suggested, including genetic predisposition and riboflavin deficiency.

Gastric­Impaction­and Stasis
Ratite chicks will eat and possibly impact on various foreign objects and almost any substrate:
sand, gravel, straw, long grass, or plastic turf materials. Emus seem slightly less prone to this than
ostriches or rheas. Ingested foreign bodies may also perforate the proventriculus or gizzard causing
septic peritonitis, similar to hardware disease in cattle. Management activities that may predispose
to impaction include irregular feeding routines, rapid changes in diet, lack of grit, movement of
birds onto a substrate that is novel to them, and any change in routine that stresses the birds.
Gastric stasis can also occur in ostrich chicks in the absence of ingested foreign material, with low
or high environmental temperature and gastric infection implicated in addition to the factors listed
above. Clinical signs may be acute and resemble colic as seen in other species, or they may be
chronic and include listlessness, reduced appetite and fecal output, decreased size and increased