By Dee Griffin, Great Plains Veterinary Educational Center, University of Nebraska, 2014
The FDA’s “Guidance for the Industry” (GFI) 209 released in December 2013, announced that ALL antibiotic feed additives would, within three years, fall under the Veterinary Feed Directive (VFD) regulations. The VFD regulations require a prescription for all antibiotic feed additives and can be used only for “treatment”, “control” and/or “prevention”. All antibiotic feed additives that are medically important to humans in any way would lose usage intended for production purposes such as improved weight gain and/or improved feed efficiency.
Pulmotil® is the first antibiotic feed additive for cattle approved by the FDA for use under their VFD regulations. Pulmotil® contains the same active ingredient, tilmicosin, as the injectable Micotil®. Pulmotil® is approved by the FDA for Bovine Respiratory Disease (BRD) “control” for groups of cattle in the early stages (as soon as 10% are affected) of a BRD outbreak associated with Mannheimia haemolytica, Pasteurella multocida and Histophilus somni. A Pulmotil® prescription is valid for 45 days from issuance or the effective date noted on the VFD by the veterinarian.
Once BRD is diagnosed in at least 10% of the group of cattle, Pulmotil® can be fed for 14 days. The approval requires Pulmotil® to be fed for a full 14 day treatment regimen. The window for initiating Pulmotil® use is during the first 45 days after cattle have arrived at a confinement feeding facility. Therefore if Pulmotil® treatment is initiated on day 45 the group would finish the regimen would be complete on day 59 of the feeding period.
To use Pulmotil® for BRD, or any other VFD antibiotic, the owner’s veterinarian must be licensed to practice in the state in which the cattle reside. Diagnosis of BRD in a group of cattle must be consistent with the BRD diagnostic protocol established by the cattle owner’s veterinarian. That means the veterinarian must outline in writing the disease signs they want the cattle owner’s key employee(s) to identify in order to establish a diagnosis of BRD in a cattle group. The signs can all be visual, therefore the FDA does not require cattle to be removed from the group for physical examination nor record rectal temperatures to diagnose BRD. Their veterinarian’s written BRD diagnostic protocol must be on file in the cattle operation’s office. Additionally, their veterinarian must have trained the identified key employees on how to use their BRD diagnostic protocol.
Once, BRD is diagnosed in 10% of a cattle in a group Pulmotil® can be used. There are two exclusions: 1) Pulmotil®, a macrolide class antibiotic , cannot be used if a different macrolide has been previously used in the cattle group. For example, if a macrolide such as Draxxin®, Micotil®, Tylan®, Zactran® or Zuprevo® was given to the cattle on arrival as metaphylaxis (mass medication), Pulmotil® could not be used on the group. 2) Pulmotil® cannot be given to an animal within three days of having received a non-macrolide antibiotic. Therefore, if the group had been mass medicated with Excede® on arrival or fed chlortetracycline (CTC), three days would have had to elapse between the previous antibiotic treatment and the first feeding of Pulmotil®. 3) Since the feed additive Tylan® is also in the macrolide class of antibiotics it should not be included in the ration during the 14 day Pulmotil® treatment period.
Pulmotil® is not intended to treat cattle suffering from severe BRD, therefore if an animal(s) begins exhibiting severe BRD signs while being fed Pulmotil®, the cattle with the severe BRD signs should be removed from the cattle group for individual treatment. The BRD treatment selected for an animal(s) removed from a group being fed Pulmotil® must be a non-macrolide antibiotic. Non-macrolide antibiotic examples include: Excede®, Excenel®, Nuflor®, and Oxytetracycline. Once the treatment for severe BRD has ended the treated animal may be returned to the group of cattle being fed Pulmotil® and the three day delay between a non-macrolide antibiotic does not apply to the individually treated animal that was treated while being fed Pulmotil®. Note: Pulmotil® has a 28 day withdrawal before treated cattle can enter the food chain.
To use Pulmotil® it must be included in a complete / total mixed ration (TMR). No additional feed stuffs can be available for the cattle to eat. Therefore supplemental forage in hay feeders, energy and mineral supplement tubs must be removed while using Pulmotil®.
The 5.68 mg / lb. dose of Pulmotil® must be delivered to the cattle in the TMR at between 1.5 and 2% of the average weight (BW) of the cattle group on a Dry Matter Basis (DMB). See Table 1 (http://go.unl.edu/bpdb).
• For example: If the TMR is 67% DM (33% moisture), average cattle BW is 500 lbs. and they will eat between 1.5% and 2% of their BW on a DMB; then the Pulmotil® dose would be delivered in between 11.2 lbs. and 15 lbs., of As Fed (AF) feed.
• Calculations:
o 500 lbs. x 1.5% BW = 7.5 lbs. feed DM. 7.5 lbs. of dry feed / 0.67 moisture = 11.2 lbs. of As Fed TMR
o 500 lbs. x 2.0% BW = 10 lbs. feed DM. 10 lbs. of dry feed / 0.67 moisture = 15 lbs. of As Fed TMR.
My observations, as well as the observations of some of the leading beef stocker and feeder cattle nutritionists, over the decades of working with newly received cattle in confinement feeding facilities, are that the 1.5% to 2.0% DM intake window the FDA requires for using Pulmotil® will typically occur between 7 days after arrival (days on feed (DOF)) and 21 DOF. There are groups whose intake will stay below 2.0% out to 28 DOF, but these group are not typical and most often associated with mismanaged / never-managed, comingled, high-stressed cattle.
Intakes during the first 7 DOF can be inconsistent and beyond 21 DOF the aggression at the feed bunk caused by limiting cattle to 2.0% of their BW on a DMB will lead the more aggressive cattle to over consume the 2.0% BW limit and therefore over consume Pulmotil® which leads to less ration available to the more timid and sickly cattle in the group and therefore under dosing of Pulmotil® to the cattle that most like need the medication. Considering eating behavior, I would not suggesting starting a 14 day Pulmotil® treatment regimen after cattle are 14 DOF. For what it is worth, if the cattle were healthy on arrival, the BRD incubation is typically 5 to 7 days so starting Pulmotil® prior to 5 to 7 days would generally not be required; unless they come off truck meeting the 10% BRD diagnosis threshold.
Pulmotil® is available to beef cattle raisers in three different concentrations: Type “A” Article that contains 90.7 grams of tilmicosin / lb.; Type “B” Article that contains 18.1 grams of tilmicosin / lb.; Type “B” Article that contains 5.68 grams of tilmicosin / lb. You will see Type “C” feed or Type “C” Article referred to in Elanco’s instructions for use or in FDA Pulmotil® use documents. Type “C” is the final mixed medicated ration or feed (TMR) containing the Pulmotil® that will be delivered to the cattle being treated with Pulmotil®.
Type “A” Article requires a feeding facility to have an FDA “Medicated Feed Mill Licensel” therefore most cattle managers will elect to use a Type “B” Article which doesn’t require having a licensed facility. The Type “B” Article containing 18.1 grams / lb. tilmicosin uses corn cob as a carrier and may not mix will in TMR containing wet distiller’s grains (WDG). The Type “B” Article containing 5.68 grams / lb. tilmicosin comes as a pellet and generally mixes will in all rations. Additionally, the 5.68 gram Pulmotil® pellet use calculation is simple because one (1) lb. of this pellet is the dose required for 1,000 lbs. of cattle.
• The “formula” for using Type “B” 5.68 g/lb. pellets = Number of Cattle X their Average.BW / 1,000 = lbs. of Type “B” 5.68 g/lb. pellets to be fed daily to this group for each of the 14 days.
• For example, if a group of 100 cattle that have an average weight of 500 lbs. is to be treated, [ 100 x 500)/1000 = 50 ], a 50 lb. bag of Type “B” 5.68 gm/lb. pellets would be the daily dose for this group.
Note: To prevent carryover between groups a “flushing” protocol must be established for feed mixing and delivery equipment.
Summary Points
• Pulmotil® requires a veterinary feed directive (prescription) and is valid for 45 days from issuance or the effective date noted on the VFD
• Pulmotil® is for control of BRD in confinement feeding cattle groups that have had as least 10% diagnosed with clinical BRD
• BRD diagnosis must be meet the cattle operation’s licensed veterinarian written diagnostic protocol and the written protocol must be on file at the cattle operations
• Pulmotil® must be used in a TMR and no supplemental ration or roughage can be provided
• The cattle operation’s key BRD employees making the BRD diagnosis must have been trained by the operations licensed veterinarians and their training documentation must be on file at the cattle operations
• Cattle cannot be treated with Pulmotil® if they have previously received a macrolide class antibiotic while at the cattle operation, or within three (3) days of being treated with a non-macrolide antibiotic
• Pulmotil® is not intended for treatment of cattle with severe BRD, therefore an animal(s) developing severe BRD while being treated with Pulmotil® should be removed from the group and treated individually with a non-macrolide class antibiotic and then returned to the group being treated with Pulmotil®
• Pulmotil® Type “C” TMR must be feed at between 1.5% and 2.0% of average BW on a DMB
• Pulmotil® treatment must be initiated within the first 45 days after arrival (DOF)
• Pulmotil® must be fed for the full 14 day treatment regimen
• Pulmotil® has a 28 day withdrawal before treated cattle can enter the food chain
• Appropriate flushing protocol should be documented and utilized
References:
1. Pulmotil® (tilmicosin) User Guide for Cattle. PUL25753, USBBUPPX00039
2. Veterinary Licensing Req. https://www.federalregister.gov/articles/2013/12/12/2013-29696/veterinary-feed-directive#h-28
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