Day-old chicks affected by omphalitis show distinct anatomical pathology features including enlarged yolk sacs, necrotic yolk stalks, and abdominal distension, all of which compromise chick viability and farm productivity. These findings highlight the urgent need for strict hatchery hygiene and early detection protocols.
Introduction
Omphalitis, also known as yolk sac infection, is a bacterial infection of the umbilicus that significantly contributes to chick mortality during the first week post-hatch. The condition is often linked to suboptimal hatchery hygiene and can lead to severe economic losses in poultry production. Studies have shown that pathogens such as Escherichia coli and Salmonella spp. are frequently implicated in these infections1.
Clinical and Gross Features
Day-old chicks (DOCs) with omphalitis typically present with small body size, dull feathers, protruding yolk sacs, and unhealed umbilici. Necropsy findings reveal abdominal distension, necrotic yolk stalks, and greenish, foul-smelling yolk sacs, which are hallmark indicators of infection1.
Pathological Changes
Histopathological examination often reveals necrosis of yolk sac tissues, infiltration of inflammatory cells, and vascular congestion. These changes impair yolk absorption, leading to poor chick growth and increased susceptibility to systemic infections. In severe cases, septicaemia may occur, further elevating mortality rates2.
