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Primary Endodermal Epithelial Cell Culture from the Yolk Sac Membrane of Japanese Quail Embryos
Published on: March 10, 2016
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RISK FACTORS ASSOCIATED WITH YOLK SAC RETENTION IN CAPTIVE-BRED HUMBOLDT PENGUIN (SPHENISCUS HUMBOLDTI) CHICKS
Eleanor L Taylor1, Edmund J Flach2, Taina Strike2
1Royal Veterinary College, Hatfield, Hertfordshire, AL97TA, United Kingdom.
Summary
Yolk sac retention was common in captive Humboldt penguin chicks, affecting 65% of those over 7 days old. This condition is linked to poor growth and may stem from parental neglect and insufficient feeding.
Area of Science:
- Avian Medicine
- Wildlife Biology
- Veterinary Pathology
Background:
- Yolk sac retention is a concern in captive bird populations.
- Humboldt penguins (Spheniscus humboldti) are susceptible to various health issues in captivity.
Purpose of the Study:
- To investigate the prevalence and risk factors of yolk sac retention in captive Humboldt penguin chicks.
- To identify potential causes and associations of yolk sac retention in this species.
Main Methods:
- Retrospective analysis of necropsy reports from 141 parent-reared Humboldt penguin chicks that died between 2014 and 2018.
- Defined yolk sac retention as presence of yolk sac in chicks aged 7 days or older at postmortem.
- Analyzed demographic and pathological variables to identify risk factors.
Main Results:
- Yolk sac retention was observed in 65% of chicks aged 7 days or older.
- Chicks with retained yolk sacs were more likely to have minimal gut contents, a prominent bursa of Fabricius, and be the first-hatched chick.
- A trend indicated poorer body condition, reduced weight, and crown-rump length in chicks with retained yolk sacs.
Conclusions:
- Yolk sac retention is a common condition in this captive Humboldt penguin colony.
- The condition is associated with indicators of suboptimal feed intake and growth.
- Parental neglect leading to starvation and absorption arrest is hypothesized as a potential cause.
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