Histological and Mucin Histochemical Characteristics of the Zygomatic Salivary Gland of Persian Leopard (Panthera Pardus Saxicolor) and Domestic Cat (Felis Silvestris Catus)

Introduction: The zygomatic salivary gland is only present in carnivores. Most studies related to the characterization of the zygomatic salivary are pivoted around the domestic species, but only few studies are available on the zygomatic salivary gland of wild species. We carried out this study with the aim of providing information on the histological and mucin histochemical features of the zygomatic salivary gland in the Persian leopard in comparison with that of the domestic cat. Methods: This study was executed on 2 Persian leopards and 3 domestic cats. The samples were collected from all animals and fixed in 10% neutral buffered formalin. Hematoxylin-eosin (H&E) and Masson’s trichrome staining were used for general histological study. Periodic acid-Schiff (PAS), Alcian blue (AB) at pH values of 1.0 and 2.5 and PAS-AB (pH 2.5) were used for the mucin histochemical examination. Results: Histological studies showed that the zygomatic salivary gland in the Persian leopard was generally similar to that of the domestic cat with some differences. Lobulation was incomplete in the Persian leopard. The parenchyma was composed of mucous acini, related serous demilunes, and few serous acini clusters with differences between two species. Mucin histochemical investigation showed that the secretory units contained neutral, acidic carboxylated, and acidic sulfated mucins varying in quantity and distribution. Conclusion: This study is the first description of the histological and mucin histochemical features of the zygomatic salivary gland of the leopard. The finding of the present study showed large similarities between the Persian leopard and domestic cat.