Vol. 9, Issue 10, Part E (2025)

The present study compared the ultrastructure of pancreatic islets of Langerhans in buffalo, sheep, and goat, focusing on α, β, δ, and PP cells. The islets were irregularly distributed among acini and varied in size. In buffalo, α-cells were peripheral with highly electron-dense granules (0.20-0.61 μm) surrounded by distinct halos, abundant rER, and prominent mitochondria, indicating high secretory activity. In contrast, sheep α-cells had fewer, less dense granules (0.18-0.32 μm) with indistinct halos, while goat α-cells possessed the smallest granules (0.12-0.18 μm) without halos. Buffalo β-cells, centrally located, contained dense granules (0.24-0.47 μm) with distinct halos and well-developed Golgi apparatus, whereas sheep β-cell granules were larger (0.30-0.47 μm) but less electron dense, and goat β-cells showed smaller, heterogeneous granules (0.20-0.29 μm). δ-cells were peripheral in all species; however, goat δ-cells exhibited unique dendrite-like cytoplasmic projections with lozenge-shaped granules (0.14-0.25 μm). PP cells were fewer in number, smallest in size, and showed scarce organelles across all species. Overall, buffalo exhibited the most metabolically active islet cells, while goats showed structural adaptations suggesting intercellular communication.