Lab 8 - Examination of the Ruminal Fluid

Question 1

Indications for ruminal fluid examination:

Answer 1

• Diagnosis of ruminal diseases

- Evaluation of ruminal fluid before use in therapeutic transfusion (transfaunation).

Question 2

How to obtain ruminal fluid

Answer 2

By orogastric tube:

By ruminal puncture:

Question 3

How to use orogastric tube:

Answer 3

• The cow is restrained
• stomach tube is passed down the nasal passage or through the mouth.
• measure the length of the tube required to be passed.
• Tubes with internal diameters <1.5 cm may become obstructed with ingesta and are not recommended for rumen fluid collection.
• A dental gag or a speculum is fixed in the mouth
• The tube is passed over the base of the tongue (or through the gag) into the esophagus.
• Animal swallows, the tube is advanced down the esophagus.
• The tube is passed until it reaches the level of the rumen.
• Placement of the tube within the rumen is confirmed by auscultation of the abdomen as air is simultaneously blown into the tube.
• The distinctive odor of fermented gas will be detected coming from the end of the tube.
• A stirrup pump is attached to the tube and used to withdraw a sample.
• The initial fluid portion should be discarded because it often contains an excessive amount of saliva = elevates the pH of the fluid.
• Tube has to be removed with a downward motion. This prevents rumen contents from leaking out of the tube and entering the trachea as the tube is withdrawn.

Question 4

How to perform ruminal puncture:

Answer 4

Ruminal puncture (in sterile conditions) is performed on the left side of the animal, by inserting a needle into the ventral rumen and aspirating a sample of rumen fluid.

The site is marked by the horizontal line level with the top of the patella about 15 to 20 cm posterior to the last rib. By this way 3-5 ml of sample can be obtained.

However, this sample is not proper for all type of examinations.

Question 5

-Transportation of ruminal fluid for long distance

Answer 5

must be done in double jacket container.

-Estimation of chloride and ammonia conc. can be delayed up to 9 hrs in room temperature and up to 24 hrs in refrigerator