Veterinary Feed Directive Questions and Answers (Part III)

The Veterinary Feed Directive was developed out of the concern for antibiotic resistance associated with daily antibiotic use in animal feeds. Photo courtesy of Troy Walz.
The Veterinary Feed Directive was developed out of the concern for antibiotic resistance associated with daily antibiotic use in animal feeds. Photo courtesy of Troy Walz.

By Rob Eirich, Nebraska Beef Quality Assurance, Nebraska Extension; Matt Luebbe, UNL Beef Feedlot Specialist; Richard Randle, Nebraska Extension Beef Veterinarian; and Dee Griffin, UNL-Great Plains Veterinary Educational Center

KEY POINTS: When the VFD regulations go into effect, they will ONLY apply to antibiotics used in the feed! They will not affect other feed use medications such as; ionophores, coccidia, other parasite and insect control drugs, or reproductive control medications. VFD regulations will not apply to antibiotics used by injection, tablet, bolus or water.

Here is the link for Part 1: http://go.unl.edu/fkhd
Here is the link for Part 2: http://go.unl.edu/2xxv

WHEN DOES THIS REGULATION TAKE EFFECT?
It went into effect June 3, 2015. Currently, feed manufactures are revising medicated feed labels to remove all feeding performance statements. These labels will read for use to treat, control or prevent a disease. The first of these revised labels will be available January 1, 2016. Labeling transition will continue to January 1, 2017 when all feed grade antibiotic will require a valid VFD.

WHAT PRODUCTS REQUIRE A VFD?
All feed use antibiotics that the FDA, World Health Organization and Center for Disease Control (CDC) considers “medically important to humans”. Currently, the FDA has approved one VFD antibiotic, tilmicosin (Pulmotil) for use in cattle feed to control Bovine Respiratory Disease (BRD).

Medically important antibiotics currently being used in cattle feeds that have label indications for prevention, treatment and/or control of specific bacterial disease as required by the VFD regulations, but that will require new approvals by the FDA to continue the feed antibiotic use when the VFD regulation becomes effective in December 2016 include:

• Chlortetracycline (Aureomycin, CLTC, Pennchlor)
• Chlortetracycline + Sulfamethazine (Aureo S 700)
• Neomycin + Oxytetracycline (Neo-Terramycin, Neo-Oxy)
• Oxytetracycline (Terramycin, Pennox)
• Tylosin (Tylan)
• Virginiamycin (V-Max)

WHAT PRODUCTS DON'T REQUIRE A VFD?
VFD regulations focus on “Medically Important Antibiotics” as these represent the only medication type that has been identified that the use in livestock feed could potentially jeopardize the drug’s effectiveness in humans. Therefore medications used to control parasites, reproduction, bloat, etc. will not require a VFD. These include:

• amprolium (Corid),
• bacitracin (Albac, BMD),
• bambermycin (Gainpro),
• decoquinate (Deccox),
• fenbendazole (Safe-Guard),
• laidlomycin (Cattlyst),
• lasalocid (Bovatec),
• melengestrol acetate (MGA),
• methoprene (Altosid),
• monensin (Rumensin),
• morantel (Rumatel),
• poloxalene (Bloat Guard)
• ractopamine (Optaflexx, Actogain),
• tetraclovinphos (Rabon).

CAN A VFD MEDICATION BE USED IN A FEED THAT CONTAINS OTHER FDA APPROVED FEED ADDITIVES?
Yes, provided the FDA has approved the medications to be used together in the same feed. For decades the FDA has approved combination use of monensin (Rumensin), tylosin (Tylan) and melegestrol (MGA) in the same feed. Tilmicosin (Pulmotil), the only VFD antibiotic currently approved by the FDA is approved for combination use with monensin. There is no reason to think the FDA will not continue to approve combination use of VFD medications approved in the future with other FDA approved feed medications.

Examples for the use of the currently approved VFD, we will refer to as “T-antibiotic”

EXAMPLE: Newly Weaned Calves
• Cattle producer contacts their vet about newly weaned calves that are developing pneumonia and indicates that at least 10% are showing the DART signs (depression, loss of appetite, respiratory movement changes and an elevated temperature). These were signs they and their vet had previously discussed as keys to early diagnosis of pneumonia.

• Their vet writes a VFD using the form provided for “T-antibiotic”.
o The forms includes the name, address, phone of the cattle owner and the veterinarian
o The location of the cattle is noted on the form
o The form also indicates how many cattle are to be covered by the VFD and their approximate weights
o The amount of VFD medication that will be needed is calculated and recorded on the form (not required in the final rule)
o A note is included if the VFD drug is to be used in combination with another drug as approved by the FDA
o The “effective date” of the VFD and the “expiration date” as calculated from the effective (start) date is listed
o The required withdrawal time is record on the VFD form
o The veterinarian signs the form and provides a copy for both the cattle producer and for the feed distributor that will provide the VFD medication.

• For this example the VFD for “T-antibiotic” has a 45 day “expiration date” calculated from the “VFD effective date” listed on the VFD form by the veterinarian. This means that the VFD therapy must be initiated within the 45 day window from the “VFD effective date” to the “VFD expiration date” … BUT that allows for a complete therapeutic cycle to be completed.

• The VFD approved “T-antibiotic” will be fed to 100 calves that average 500 lbs.

• The VFD for “T-antibiotic” requires that at least 10% of the cattle in the group are exhibiting signs of pneumonia.

• The VFD “T-antibiotic” is fed for 14 continuous days and a 28 day withdrawal is assigned at the end of the 14 day treatment.

• To meet the 45 day VFD expiration window, the “T-antibiotic” must be started not later than 31 days from the VFD effective date. (45 day window – 14 therapy cycle = 31 day window to start a therapy cycle).

• Three concentrations of “T-antibiotic” are available for on-farm mixing. For this example a “Type B Article” 5.68 gm / lb product will be used. This is especially convenient for this examples as the dose is 5.68 mg / lb of calf. Therefore, each pound of 5.68 gm / lb Type B product will medicate two 500 lb calves each day during the 14 day treatment. The total amount of Type B product to be used for the 100 calves weighing 500 lbs for the entire 14 day treatment will be 700 lbs.

• The ration being fed to the calves is 75% dry matter (DM).

• “T-antibiotic” has a few use restrictions that must be followed. They are;
o Cattle in the group that are exhibiting clinical signs of pneumonia should be removed for individual treatment
o An injectable antibiotic in the same macrolide class cannot be used in conjunction with or prior to the use of the “T-antibiotic”
o The “T-antibiotic” must be used in a complete feed which means no other feed or feedstuff can be offered
o Cattle must receive between 1.5% and 2.0% of their body weight of the complete feed on a dry matter basis (DMB)
o No other feed can be offered while feeding the VFD medicated feed (no extra hay or lick tubes).
o The feed mixer used to prepare the complete feed should be “flushed-out” before being used to mix feed not containing the tilmicosin

• Between 1000 As-Fed lbs to 1333 As-Fed lbs of the 75% DM complete ration will meet the 1.5% to 2.0% daily intake restriction for the 100, 5 CWT calves required by the VFD for “T-antibiotic”.

• The amount of the “T-antibiotic” 5.68 gm/lb of the Type B product used daily for the 100, 5 CWT calves will be 50 lbs. This amount will be added to the 1000 to 1333 lbs of As-Fed daily feed delivery.

EXAMPLE: Feeder Planning on Purchasing Several Loads of High Risk Calves in the Next Month
• A vet’s client, John Doe is planning to buy 10, 100 head loads of 5 CWT high risk calves starting the first of next month (e.g. Aug 1) with the last load coming in during the next four weeks.

• Vet needs to contact the VFD medication supplier (e.g. feed store) to let them know John Doe will be using a VFD medication and what concentration of the medication they want to use. It may take the supplier 1 to 2 weeks to get the medication in stock.

• John Doe’s vet (licensed in the state where the cattle will reside AND as a VCPR) can write a VFD for “T-antibiotic” and as a “Special Instruction” indicate the “VFD to begin Aug1, 2015”.

• The expiration date for “T-antibiotic” is labeled as 45 days. Therefore in this example the VFD usage window will be from Aug 1st to Sep 14th. WHICH MEANS, all feeding of “T-antibiotic” on this VFD must stop at midnight Sep 14th.

• “T-antibiotic” has a 14 day feeding cycle. Therefore all groups for cattle identified to receive “T-antibiotic” must be started on a treatment cycle by Aug 31st.

• If there is any delay in receiving the anticipated 10 loads of cattle, a second VFD will need to be written to extend to potential treatment past the expiration of the original VFD (Sep 14th).

• The dose of “T-antibiotic” is 5.68 mg/lb per day. “T-antibiotic” is available in a 5.68 gm/lb pellet. Therefore the dose would be 1 lb of these pellets per 1,000 lbs of cattle being treated.

• “T-antibiotic” has a couple of important feeding restrictions:
o Must be feed to cattle consuming feed between 1.5% and 2.0% of the body wt. on a DMB
o No other feedstuff can be offered … not extra hay, lick tubes, etc.

• The total amount of “T-antibiotic” that will be need for a group of 100, 5 CWT calves will be:
o 1 pound of pellets will treat 1,000 lbs of cattle per day
o 5 CWT x 100 head = 50,000 lbs. … 50,000 lbs / 1000 lbs = 50 lbs of pellets / day,
o 50 lbs of pellets x 14 days therapy cycle = 700 lbs of “T-antibiotic” pellet (5.68g/lb)

• The total amount of feed that is 65% dry matter (DM) fed to a group of 100 cattle weighing 5 CWT would be:
o Feed intake can range between 1.5% to 2.0% of BW on a DMB
-At 1.5% BW (DMB) = 500 x 1.5% = 7.5 lbs (DMB) daily feed.
▪7.5 lbs / 65% = 11.5 lbs As Fed (AF) feed per day
▪11.5 lbs daily x 14 days = 161 lbs AF / head x 100 head = 16,100 lbs AF feed
-At 2.0% BW (DMB) = 500 x 2.0% = 10 lbs (DMB) daily feed.
▪10 lbs / 65% = 15.4 lbs As Fed (AF) feed per day
▪15.4 lbs daily x 14 days = 216 lbs AF / head x 100 head = 21,600 lb AF feed
o Both the total amount of VFD medication to be used and the total amount of feed it will be mixed with must be recorded on the VFD form.

• All parties (vet, VFD medication suppler, and producer) must have a copy of the completed VFD form. These copies must be retained for two years.

• The VFD medication supplier (feed mill) must have a copy before the medication can leave their premise. It can be a fax or email copy, BUT, a hard copy must be provide to the VFD medication supplier within 5 working days!
o Note: if the VFD supplier is new to working with VFD medications, they must notify the FDA of their intent to distribute VFD medications. This is a “one-time” notification. Once the notification has been submitted the supplier will not have to repeat the process, even if a new VFD product becomes available for them to distribute.
o Example of a form for notifying the FDA: http://go.unl.edu/nwzv