factors affecting egg hatchability and captive reproductive management of scarlet ibis( eudocimus ruber)
Key words: Birds, reproduction, captive breeding, artificial incubation, embryo diagnosis, semi-altricial development.
Efficient captive breeding programs are crucial for the conservation of threatened avian species. Embryo diagnosis, a routine practice that enhances efficiency in industrial poultry farming, can be adapted to wild bird breeding management. This study aimed to describe the embryonic development of semi-altricial scarlet ibis (Eudocimus ruber) while identifying critical landmarks for diagnostic and age determination purposes, supporting both artificial incubation and field research on the species. We used eggs collected from a captive population in northern Brazil. A total of 50 embryos were analyzed from day 0 to day 18, focusing on external morphological traits observable through macroscopic examination. Key diagnostic features included the sequential formation of the beak, eyes, neck, feathers, and embryonic annexes. We compared the development of the semi-altricial scarlet ibis with reference descriptions of precocial and altricial species to evaluate the suitability of comparisons between different postnatal growth patterns. The semi-altricial scarlet ibis exhibited heterochronic variations of up to four days in critical developmental landmarks compared to precocial species with similar incubation periods. These findings suggest that developmental timelines established for precocial species may not be reliable for accurately staging altricial and semi-altricial embryos. Interestingly, the median timing of significant developmental events in the scarlet ibis aligned more closely with those of other altricial species. The daily embryonic milestones described herein provide a valuable reference for scarlet ibis captive breeding programs and contribute to broader conservation efforts for other Threskiornithidae family members or species within the Pelecaniformes order, addressing the limited research on semi-altricial avian development.
Key words: Birds, reproduction, captive breeding, artificial incubation, embryo diagnosis, semi-altricial development.Palavras-chave: Aves, reprodução, reprodução em cativeiro, incubação, diagnóstico de embriões, desenvolvimento semi-altricial.Palavras-chave: Aves, reprodução, reprodução em cativeiro, incubação, diagnóstico de embriões, desenvolvimento semi-altricial.Palavras-chave: Aves, reprodução, reprodução em cativeiro, incubação, diagnóstico de embriões, desenvolvimento semi-altricial.Palavras-chave: Aves, reproducção, reprodução em cativeiro, incubação, diagnóstico de embriões, desenvolvimento semi-altricial.