17- Ruminant GI 1

Question 1

Which muscle?

Answer 1

External abdominal oblique

Question 2

What direction does the muscle fibers of the external abdominal oblique run?

Answer 2

Caudoventrally to the linea alba

Question 3

Muscle?

Answer 3

Internal abdominal oblique

Question 4

What direction does the muscle fibers of internal abdominal oblique run?

Answer 4

Cranioventral fashion

Question 5

Muscles 2 and 3?

Answer 5

2) Transversus abdominus
3) Rectus abdominus

Question 6

What direction do the rubbers of transversus abdominus run?

Answer 6

Dorsal to ventral

Question 7

What direction do the fibers of Rectus abdominus run?

Answer 7

Cadually to the pubic brim
shouldnt come across unless doing surgery in the flank area

Question 8

What are the most important nerves supplying the abdominal wall?

Answer 8

T13, L1, and L2

Question 9

Each nerve is composed of a dorsal and ventral branch. What structures do each branch supply?

Answer 9

Skin is supplied by the dorsal and ventral branches

Deeper structures are supplied by the ventral branches

Question 10

Identify the structures pointed to by purple arrows

Answer 10

Question 11

Identify the structures point to by purple arrows

Answer 11

Question 12

Identify structures 1-6

Answer 12

1) Dorsal sac of rumen
2) ventral sac of rumen
3) Superficial wall of GO
4) Deep wall of GO
5) Omental bursa
6) descending duodenum

Question 13

Identify the pillars and folds of the rumen

Answer 13

Question 14

Identify the 4 distinct layers of the rumen content

Answer 14

Question 15

What does the muscosa of the reticulum look like?

Answer 15

Distinct honeycomb pattern

Question 16

What is 4?

Answer 16

Reticular groove

Question 17

What is the purpose of the reticular groove in ruminants?

Answer 17

In an unweaned ruminant, the groove shunts milk directly to the abomasum and bypasses the rumen

Question 18

What is 7?

Answer 18

Omasum- mucosa looks like pages of a book, lots of long folds of tissue

Question 19

What is 8 and 15?

Answer 19

8) body of abomasum
15) pyloric part of abomasum

Question 20

Where is the abomasum located topographically?

Answer 20

Slightly to the right of ventral midline

Question 21

How does a ruminant neonate GI tract differ from an adult?

Answer 21

The abomasum in a neonate is much larger compared to the other chambers- the rumen does not grow and develop until later in life
- the introduction of scratch factor in the young animal’s diet triggers the development of rumen and population of microbes

Question 22

The small intestines lie almost entirely on the ______ side of the ruminant’s abdomen

Answer 22

Right
(Remember rumen takes up most of the left side)

Question 23

Where can the liver be located in ruminants?

Answer 23

Found almost entirely on the right side of the abdomen. It lies deep to the ribs from the ventral third of the 6th intercostal space to the upper part of the last rib

Question 24

What is the starred structure?

Answer 24

Liver