IVRI Anatomy
A free veterinary anatomy learning platform for B.V.Sc., M.V.Sc., DVM and veterinary medicine students worldwide, developed at the Veterinary Anatomy Section, ICAR-Indian Veterinary Research Institute, Bareilly—covering VCI/MSVE and international university curricula through regional anatomy, histology, embryology, comparative biomechanics, clinical notes, quizzes and revision.
Located at the rostral tip of the skull, the incisive bone forms the skeletal support for the muzzle and the upper dental pad.
Body: In the ox, the body is flattened and lacks alveoli because ruminants have no upper incisors. Instead, it supports the dense fibrous dental pad against which the lower incisors grind.
Nasal Process: Extends caudally to articulate with the maxilla and nasal bone. In the ox, there is often a nasoincisive notch where the nasal process does not fully articulate with the nasal bone, leaving a gap.
Palatine Process: Forms the rostral tip of the hard palate.
Interincisive Fissure: A distinct gap between the nasal process of the incisive bone and the maxilla, covered in life by mucosa.
Paired bones forming the roof of the nasal cavity.
Shape: In the ox, the nasal bones are relatively short and bifid (split) at the rostral end (apex), creating a double-point appearance.
Articulation: Articulates caudally with the frontal bone and laterally with the maxilla. Unlike the horse, it often does not articulate with the incisive bone rostrally, contributing to the nasoincisive notch.
Dorsal Surface: Smooth and convex.
| OX (BOS TAURUS) | Incisive: Absent teeth (dental pad). Body thin, flattened, fragile. Nasal process does not always reach nasal bone (notch present). Nasal: Apex bifid (notched). Short (compared to head length). Floating rostrally (nasoincisive notch). |
| HORSE (EQUUS CABALLUS) | Incisive: 3 incisors present. Strong, thick body. Articulates with nasal bone. Nasal: Apex pointed. Very long. Articulates with incisive bone. |
| DOG (CANIS LUPUS) | Incisive: 3 incisors present. Small, compressed. Articulates with nasal bone. Nasal: Truncated/Notched. Variable (breed dependent). Articulates with incisive bone. |
| PIG (SUS SCROFA) | Incisive: 3 incisors present. Very strong, snout-like. Articulates with nasal bone. Nasal: Long. Very narrow. Firmly united to incisive. |
| FOWL (GALLUS DOMESTICUS) | Incisive: Absent (forms beak tip). Fused, sharp tip. Nasal: Thin, flexible. Fused with Frontal (Kinetic hinge - nasofrontal hinge allows prokinesis). |
Explore the hidden mechanics of why structures are present, absent or modified across domestic and wildlife species—and how each anatomical design supports movement, function and clinical practice.
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