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Ratites 83

Fading­Ostrich­Syndrome
A specific cause of this syndrome, whose features include anorexia, gastric stasis, and extremely
high mortality in ostrich chicks less than 6 months of age, has not been determined. A combina-
tion of management‐induced stress and immunosuppression and one or more infectious agents is
likely responsible. Careful attention to management, hygiene, and biosecurity appears to be the
best prevention at present.

Other­Conditions
Other husbandry‐related diseases include trauma, predation, exertional myopathy, hypothermia,
heat stroke, intestinal accidents, and plant, heavy metal, or chemical poisoning.

­ Diet­and Feeding­Procedures

Ratites, with the exception of kiwis, are primarily herbivores; however, their digestive systems and
natural diets differ (Cillers and Angel 1999; Sales n.d.). Ostrich, emu, and rhea graze on a variety
of low energy vegetation in semiarid environments. Gastrointestinal transit time is more rapid in
the emu (5–6 hours) than in the ostrich (36–39 hours for immature birds) or rhea, species that rely
more heavily on hindgut and cecal fermentation. Commercial feeds are formulated specifically for
ostrich, emu, and rhea, and for birds of different ages and are sold by a several major feed compa-
®
nies (e.g. Mazuri ), as well as local feed coops. Cassowaries feed on a variety of fruits of the tropical
forest, but in captivity are fed a mixture of fruit, pellets, and sometimes small amounts of animal
matter (e.g. chicks, rats, meat) (Folch 1992c; Biggs 2013). Kiwis are insectivorous, feeding primar-
ily on earthworms and a variety of soil invertebrates (Folch 1992a; Sales 2005).
Although the larger ratite chicks rely on the yolk sac for nutrients and fluid for up to a week after
hatching, a pelleted or crumbled starter ration should be offered soon after hatching to encourage
development of normal feeding behavior and early weight gain (Deeming and Bubier 1999).
Without older birds to act as role models, newly hatched chicks may need assistance to identify
food and water. White dishes with patterns on the bottom, or freshly chopped greens, or brightly
colored vegetable matter floating in the water or placed on dried feed may encourage interest
(Figure 4.3).
Chicks may feed more readily from the ground than from dishes or pans. For biosecurity rea-
sons, species such as domestic chickens should not be placed with the chicks to encourage eating.
It is a matter of debate whether grit is necessary for birds fed a pelleted diet; however, the following
general recommendations have been made for grit size: starter (2/16 in.; 3 mm) at hatch to 3 weeks;
grower (2/16 in. × 3–4/16 in.; 2 mm × 5–6 mm) at 4–7 weeks; developer (4/16 in. × 6–8/16 in.;
6 mm × 9–13 mm) at 8–16 weeks; and turkey (6/16 in. × 10/16–14/16 in.; 9 mm × 16–22 mm) after
16 weeks (Mazuri/PMI Nutrition International 2012).
There is no universal program for chick nutrition (Minaar and Minaar 1992; Minaar 1998; Sales
n.d.). Most chicks are initially fed a ratite crumble or starter with at least 20% protein free choice.
If specific ratite diets are not available, a pelleted feed with approximately 15–20% protein could be
substituted (Sales n.d.). Dietary utilization of nutrients is poor initially as the digestive and absorp-
tive capabilities of the gastrointestinal tract mature over the first few weeks of life. The establish-
ment of normal GI flora is felt to occur within the first week of life. Some producers place fresh
feces from healthy adult or juvenile birds in the pen with chicks in order to transfer the appropriate