Small intestine of Ox
- The small intestine of Ox measures about 21.5 m. in the adult (Indian ox) and has a diameter of about 5 to 6 cm.
- It begins at the pylorus and terminates at the caecum. It is divisible into a fixed part and a mesenteric part
- The fixed part is duodenum and mesenteric part is arbitrarily divided into jejunum and ileum
- The duodenum is about 1m long. It begins at the pylorus at the ventral end of the 10th rib
- The first part passes upwards to the visceral surface of the liver. Here it forms a ‘S’ shaped curve
- The second part runs backwards to the tuber coxae where it turns forward forming the iliac flexure.
- The third part extends forward in contact with the terminal part of the colon and joins the mesenteric part
- It is attached to the liver by the lesser omentum, to the remainder of its extent by the mesoduodenum -a narrow fold derived from the right layer of the mesentery
- The bile duct opens into the convexity of the ventral part of the ‘S’ shaped curve
- The pancreatic duct opens about 30 cm further back
- The remaining part of the small intestine, thejejunum is arranged in numerous very close coils, which form a festoon at the edge of the mesentery
- It lies chiefly in the space bounded medially by the right face of the rumen, laterally and-below the large intestine and in front the terminal part leaves the edge of the mesentery runs forwards between the caecum
- The last 120 cm constitutes the ileum
- In the interior, lymphoid tissue occurs in the form of distinct nodules, which are either scattered – Solitary glands or in groups – Payer’s patches
- The Payer’s patches are large and are about 18 to 40 in number; in calves 35 to 50. Usually there is a very long patch close to the ileo-caecal valve
MESENTRY (OX)
The mesentery is a fan-shaped double peritoneum containing the vessels and nerves to the intestine. The visceral border is attached to the intestine and contains the mesenteric lymph glands while the parietal border or root is attached to a small area around the cranial mesenteric artery under the first and second lumbar vertebrae, the mesentery is at first short but soon reaches a length of 30 to 60 cm, sufficient to allow the intestine to reach the abdominal floor
