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82 Hand-Rearing Birds

dryness of fecal pellets, and stunted growth. The impacted proventriculus or ventriculus may be
palpable in the abdomen, but often plain or barium contrast radiographs are necessary. If the con-
dition is identified quickly, laxatives may assist in passage of the proventricular and ventricular
contents, but in most cases surgical removal is required. The prognosis depends very much on the
condition of the bird at the time of surgery; the survival rate is poor for weakened birds.
Proventricular and ventricular function may also be disrupted by localized infections by fungi,
including Candida, Aspergillus spp., and avian gastric yeast (Macrorhabdus ornithogaster). These
are often secondary to immunosuppression or another insult.

Enteritis
Enteritis may be an important problem in chicks less than 6 months of age. Inadequate sanitation,
combined with the propensity of chicks to be coprophagic, may result in outbreaks of disease. The
establishment of a normal intestinal flora within the first days of life is considered important in
preventing enteric infections. A variety of pathogens have been implicated, including gram‐
negative bacteria such as Escherichia coli, Campylobacter jejuni, Pseudomonas sp., Salmonella spp.,
and Clostridium spp.; Brachyspira hyodysenteriae in rhea; and paramyxo‐, reo‐, corona‐, adeno‐, and
herpes viruses. Systemic infection frequently follows bacterial enteritis. Cloacal prolapse may
occur secondary to diarrhea and straining and has also been associated with cryptosporidial infec-
tion in ostrich chicks. Appropriate antibacterial therapy should be provided along with fluids and
supportive care. Investigation into underlying sanitation and management protocols is essential to
prevent and control outbreaks of enteritis.

Parasitic­Disease
A variety of internal and external parasites have been identified in ratites. The most clinically sig-
nificant of these is Libyostrongylus douglassi, the proventricular worm of ostriches. Clinical signs
in affected chicks include anorexia, weight loss, depression, and death. Enteric coccidiosis is an
important cause of illness and mortality in captive kiwi chicks, particularly those raised at high
density. Regular fecal evaluation and deworming programs are essential for parasite control.

Respiratory Disease
Upper and lower respiratory disease may be significant in chicks under 6 months of age. Clinical
signs include conjunctivitis, rhinitis or sinusitis, and respiratory distress. A variety of bacterial,
fungal, mycoplasmal, and viral agents have been implicated, including Pasteurella hemolytica,
Bordetella avium, Pseudomonas aeruginosa, Hemophilus spp., and Neisseria sp. Ostrich‐specific
mycoplasmas have been identified in South Africa (Botes et al. 2005). Aspergillosis is a disease of
particular concern to ratite farmers. Infection occurs by exposure to overwhelming numbers of
fungal spores in situations with poor husbandry (in the brooder or later), or after reduction in a
bird’s immune function due to concurrent disease or other stress. Poor ventilation leading to high
levels of ammonia in the barn may predispose to outbreaks of respiratory disease. Aspergillosis
may be seen as explosive outbreaks in flocks of young chicks. Smoldering infections in individual
older birds may become clinically apparent under stressful conditions – for example, after trans-
port to a new farm. Birds may show minor or nonspecific clinical signs even when severely affected.
Treatment is rarely effective, but a variety of systemic and aerosolized antifungal medications have
been recommended.