Research Protocols

What is the protocol for weighing calves?

ensure the scale is zeroed and on level ground and test the accuracy of the scale prior to weighing the calf with something of a known weight

What is the protocol for measuring body length of a calf?

Have the calf standing with their head held forward and upright, measure diagonally from the point of shoulder to pin bone

What is the protocol for measuring heart girth of a calf?

Have the calf standing and measure right behind the front legs, measure with the side of the tape that is in inches

What is the protocol for measuring calf hip width?

Have calf standing and measure from the outside of one hook to the outside of the other

What is the protocol for measuring calf hip height?

have calf standing on level ground so that hooks are perpendicular, have base of measuring stick on the ground and measure to the tallest point of the hook

What is the protocol for measuring calf wither height?

Have calf standing on even ground with head facing forward and up, have base of measuring stick on the ground and measure to the highest point of the front shoulder

What are the jobs of the people when doing a two person blood draw?

One person with restrain the calf in a head catch or halter and ensure the calf stays restrained during the blood draw, the other person will be drawing the blood

How do you prep the area where you will be drawing blood?

first remove any debris from the area using a cotton ball or gauze then disinfect using alcohol, this can be soaked cotton balls or gauze or with a spray bottle

How do you find the vein and insert the needle when drawing blood?

secure needle into vacutainer holder prior to locating the vein, then place non-dominant thumb under the vein, once the vein is located insert the needle almost perpendicular to the skin

How do you collect blood when doing a blood draw?

Once the needle had been inserted, collect the blood using a two way needle in the vacutainer holder, once all the blood tubes have been filled at least half way remove the tube

What is a blown tube?

When you remove the needle from the calf prior to the tube being removed, these tubes need to be marked with an X and thrown away

What do you do when using multiple different blood tube types?

collect serum and non-additive tubes before additive containing tubes so that the needle is not contaminated and causes the coagulation of blood in the serum and non-additive tubes

What do you do after collecting blood from the calf?

Hold pressure on the spot where blood was collected for at least 5 seconds, after removing your fingers make sure there’s no visible blood, the observe calf for 10 minutes to make sure its not showing any signs of bleeding or distress, such as, excessive vocalizations, not lying down, or not resuming normal activities

How do you restrain the calf using the one person blood collection method?

Use pen corners or stable barriers to hold the calf in place, standing angled, the calf’s neck should be on the dominant hand side of your body, using your dominant hand elbow, hold the calf’s head to your thigh

What are the materials needed for a rumen fluid collection?

liquid container that had been prewarmed with 102F water make sure the water is poured out before placing the rumen fluid in the container, a tube that has been cleaned with chlorhexidine 2% solution and water, and a syringe that has also been cleaned with a chlorhexidine 2% solution and water

How should calves be restrained when collecting rumen fluid?

With a halter, in the Ward chute, or calf cart

How do you insert the tube when collecting rumen fluid?

Slowly insert the tube! Insert towards back left of the mouth and over the tongue to stimulate the swallowing reflex, once past the throat the tube should gently slide down the esophagus, only insert tube to the predetermined mark on the tube

How do you collect rumen fluid once the tube has been inserted?

connect a 60 cc syringe to the end of the tube, slowing pull back syringe until a negative pressure is being applied and fluid is being suctioned up, once fluid is suctioned up the tube should be kinked, syringe removed, and fluid poured into the container

How do you extract the tube when collecting rumen fluid?

Kink the tube to keep fluid from entering the trachea and lungs then slowly extract the tube

What do you to after collecting rumen fluid from a calf?

Observe the calf for 15 minutes for any abnormal behavior, such as, excessive vocalization/coughing, not lying down, not resuming eating, drinking, or play behaviors

How do you strain rumen fluid once it has been collected?

Strain the fluid through four layers of cheesecloth that has been placed over a 50mL tube with the calf’s ID. This needs to be done quickly so that the pH can be measured closest to the calf’s body temperature

How do you measure the pH of rumen fluid?

place tube with fluid in a hot bath then turn of the pH meter and unscrew the probe from the electrode buffer bottle, then rinse the probe with DI water and gently wipe off with kim wipes, then place the probe into the rumen fluid that is waiting in the hot water, wait until the pH indicator on the meter has stopped flashing then write the pH on the sheet, take the probe out of the fluid and rinse with DI water then wipe with kim wipe, then put probe back into the bottle of electrode buffer

What is the protocol for placing rumen fluid in storage containers?

When about 10 mL of fluid has been collected it needs to be separated into two tubes. The first one should be labeled “R1 w/A” and have exactly 5 mL of fluid and write down how much fluid is in the tube on the collection sheet, the second tube should be labeled “R2” and has the leftover fluid from the 50 mL tube and write down how much fluid is in this tube on the collection sheet

What is the protocol for adding acid to the rumen fluid samples?

Acid should only be added to the tube labeled “R1 w/A” and only if it has 5 mL. If the tube has 5 mL of fluid add 1 mL of acid using a pipette and mark yes on the collection sheet in the “Acid Added?” column. If there is less than 5 mL of fluid in the tube don’t add acid and write No in the “Acid Added?” column on the collection sheet

What is the protocol for storing the rumen fluid tubes?

They should be stored in the rumen fluid mini cooler until back on campus where they’ll be stored in a -20C freezer.