MORTALITY IN NEAR-TERM OSTRICH EMBRYOS DURING ARTIFICIAL INCUBATION

1. The ostrich industry in South Africa (and elsewhere) experiences a high rate of embryo mortality during artificial incubation of eggs. Mo st of this mortality takes place in the last 10-14 d of incubation. 2. We carried out post-mortem examinations on 111 embryos that died with in this period to assess the causes of this mortality. 3. Malpositioni ng and severe oedema were the predominant symptoms of dead-in-shell em bryos with 55% being malpositioned and 41% showing severe oedema. Of t hese, 22 embryos (24%) showed both symptoms. Malpositioning generally results from incorrect setting of the eggs or inadequate turning and o edema was significantly correlated with the amount of water lost from the eggs which in turn was correlated with egg size. 4. Myopathy, gros s lesions of internal organs, haemorrhage, bacterial infections and co ngenital deformities were found in less than 10% of chicks examined fo r these symptoms.