Evaluation of Physical Egg Quality of Ducks

Abstract

Duck eggs are a crucial source of affordable protein and income in many developing countries, but their marketability is often limited by variable quality and consumer concerns about defects. Egg quality traits are known to be influenced by bird age, yet limited information exists for ducks under Nigerian production conditions. This study evaluated the effects of duck age on external and internal egg quality traits. A total of 400 fresh eggs were collected from young (<6 months), prime-age (6–12 months), and older (>12 months) ducks in Danbatta Local Market, Kano State. Eggs were assessed for weight, shell thickness, shape index, albumen height, Haugh unit, yolk index, and incidence of defects. Prime-age ducks produced significantly heavier eggs (69.2 ± 2.9 g) with thicker shells (0.42 ± 0.03 mm) and superior internal quality (Haugh unit: 82.5 ± 4.1; yolk index: 0.47 ± 0.03) compared with young or older ducks (p<0.05). Shape index did not differ among age groups. Defect occurrence varied with age: blood spots were most frequent in older ducks (18.3%), shell cracks in young ducks (9.6%), while dirty shells showed no significant age effect (14.1–15.2%). Shell thickness correlated positively with Haugh units (r = 0.68, p<0.01), while egg weight was moderately correlated with yolk index (r = 0.45, p<0.01). The results highlight the physiological advantage of prime-age ducks and the distinct quality risks associated with younger and older flocks. Age-based flock management strategies could enhance egg quality, reduce postharvest losses, and improve consumer acceptance in duck egg production systems.