Lecture 25

Question 1

What are the two main layers that are present within the intestine?

Answer 1

Longitudinal and a circular layer is present

Question 2

What are the three main portions of the small intestine (in order from stomach) and provide a brief explanation of the path that is involved in them?

Answer 2

1. Duodenum- cranial portion to a descending portion to an ascending portion (curves twice) 2. Jejunum- consists of many transverse coils 3. ileum- ileocolic sphincter (where it links in with the colon)

Question 3

What are the three main portions of the large intestine?

Answer 3

1. Caecum 2. Colon- ascending, transverse, descending 3. Rectum

Question 4

Briefly describe the blood supply of the large intestine:

Answer 4

supplied by the cranial and the caudal mesenteric arteries, the cranial supplies the majority, while the caudal only supplies the last little part

Question 5

Briefly describe the junction between the large and small intestine:

Answer 5

The ileum forms a T-junction between the caecum and the colon. Turn right for the colon and turn left for the caecum. The caecum has no direct connection with the ileum in the dog.

Question 6

Briefly describe the anus structure:

Answer 6

Transition from the smooth to the skeletal muscle forms the anal sphincter.

Question 7

Name the following structures:

Answer 7

1. Iloecolic orifice
2. Caeliocolic orifice

Question 8

What is a simmilarity between the structure of the small and large intestines within pigs and ruminants?

Answer 8

Both the small and the large intestines remain within the same sheet

Question 9

Briefly describe the ascending colon of the pig:

Answer 9

The ascending colon is cone shaped, has inward and outward . coils of different diameter and has a little bit of rotation around the mesenteric artery.

Question 10

Briefly describe the ascending colon of the ruminant:

Answer 10

The ascending colon lies within the same plane and has inward and outward coils of intestine of the same diameter.

Question 11

What are the two main differences of the horse ascending colon when compared to other species?

Answer 11

1. Very large caecum (because they are hindgut fermentor)
2. Extreme elongation of the ascending colon occurs in horses

Question 12

What are taenia?

Answer 12

These are strips of longitudinal muscle. The contractions lead to the puckering of the gut and the creation of a series of haustra and produced (linear sacculation). These structures are not present everywhere.

Question 13

Name the following structures:

Answer 13

1. RVC
2. taenia
3. LVC
4. LDC
5. RDC
6. TC
7. DC
8. Rectum
9. taenia
10. haustra
11. taenia
12. caecum