McClellan: Alternatives for Fall Health Management

Preventative measures could reduce the need to treat cattle for foot rot or other forms of lameness.

By Dave McClellan

Lameness and the prevention of it have become increasingly more important to the cattle feeding industry in the last couple years.  Not only does it have profitability implications due to lost performance it also is a growing animal welfare concern.  It has been reported that approximately 16% of all cattle health issues are lameness related.

Eastern Nebraska and Western Iowa are the two pieces of the major cattle feeding area that experience numerous issues with Foot Rot and what seems to be an ever increasing frequency of Digital Dermatitis, better known as Hairy Heel Wart.

For at least 40 years that I’m aware of foot rot was controlled in much of this area by feeding chlortetracycline (CTC) at an off label, illegal level.  Regular use was 4 grams for five days or 5 grams for four days which was repeated if necessary.  Obviously off label and illegal, but highly effective.  The Veterinary Feed Directive (VFD) changed all that this year.

In an effort to be proactive as opposed to reactive or figuring ways to not get caught many of us examined our trace mineral status.  We looked at levels, but more importantly at sources.  Most of us don’t use oxide forms of zinc, copper, manganese or cobalt, but rather a blend of amino acid complexes and Sulfates.  The existing research on zinc levels and zinc sources has long convinced most of us to raise our zinc level and to get part of our zinc from an amino acid complex.  As we reasoned through possible solutions to the problem of treating foot rot without CTC it became clear that the best route to pursue was prevention. 

Many of us had tried foot rot vaccine, but generally with less than hoped for results (it actually works better as a treatment than prevention, especially in “natural” cattle).  Raising the levels didn’t appear to offer much promise so we looked at source.  Leaving the amino acid complex fraction alone was defendable. Feeding at levels above the manufacturers recommended feeding levels, although effective, is expensive. 

So our attention centered on replacing all or part of the sulfate fraction with an effective yet economical alternative.  We looked at proteinates, polysaccharides, and various complexes.  We took a hard look at hydroxyl forms and liked what the data showed.  High potency levels, low rumen solubility, and more focus on the small intestine for absorption all added up to better bioavailability at a manageable cost. 

Typical trace mineral levels of >100 ppm zinc, >20 ppm copper, >30 ppm manganese, and >.10 ppm cobalt are common.  Replacing a portion of the sulfates with a hydroxyl package decreased the incidence of foot rot occurrence, lessened the severity of the ones that needed treating, improved the response to treatment with an approved antibiotic, and complied with VFD.  A win-win.  The existing body of research and lab data on Hydroxyl minerals shows almost a 2x improvement in bioavailability over sulfate forms of Zn and Cu. 

Being proactive gave us a solution we can live with at a cost we can afford.  We can get to this point by using more amino acid complexes, but we are cognizant of cost.

Digital dermatitis (hairy heel wart) has probably been a problem much longer than the four to five years that it’s been on our radar screens.  We most often called the occurrence a non-responsive Foot Rot.  As you look across the landscape at Hairy Heel Wart occurrence the cattle are usually greater than 1,000 pounds.  They have been on premises long enough for the causative spirochete to have manifested itself.  The changes we made in the trace mineral package for foot rot have decreased the frequency of hairy heel wart as well but not to an acceptable level, perhaps this is a place where the amino acid complex might be a better choice.  If and when enough research data becomes available that might change the current thinking.  We don’t see it in every feed yard, but if the yard has fed many Holsteins the odds are much greater that the problem will show up.  If the facility has the problem it’s not going away any time soon. 

Foot bathes have proven to be, to this point, the best intervention and work well if designed correctly.

  1. Build on level ground if possible, if not enter going uphill.
  2. Concrete in and out ramps of 10 to 12 feet in length work best getting some of the dirt, mud, and manure off the feet going in and recapturing some of the solution going out.
  3. The basin portion should be 8 feet wide and 10 to 12 feet in length to allow multiple immersions of all four feet.
  4. Create a 6” x 6” x 2” sump on one side of the basin with a 4” piece of PVC inserted through the basin side wall to facilitate easy, thorough draining and cleaning.
  5. In an 8’ x 12’ basin 150 gallon of water to 7.5 gallon of Formaldehyde will give you 4” of depth getting good foot immersion.
  6. Formaldehyde can be drained directly on the ground and does not create a biohazard.
  7. We can run 500 head or more through a single charge of chemical unless cattle are really dirty.
  8. Other chemicals such as copper sulfate or zinc sulfate also can be used, but disposal care must factor in concentration levels and cost goes up.

It should be noted that several branded dairy organizations do not allow the use of formaldehyde and are discouraging foot bath use entirely choosing instead to work on prevention.

In yards where we know we have the organism we run all cattle through the foot bath as part of initial processing and any other time they go through the chute.  If we have an outbreak we will run that entire pen through two to four days in succession.  If we have just an animal here and there showing symptoms we will stand that animal in the foot bath for 20-30 minutes as a treatment.  We have picked individual feet up and packed the lesion with oxytetracycline, but have better success with the foot bath treatment.  We have excavated the basins in my client yards, but know of a yard in Eastern Nebraska that has an above ground curbed basin that reportedly works equally well.  I would still recommend concrete entry and exit ramps.

By the time this article appears in print, harvest will be well underway if not winding down. For several reasons we have moved away from corn silage in favor of dryer roughages.  The widespread use of ethanol coproducts has us looking for ways to dry up the ration.  We use a lot of dry bailed crop residue such as straw, corn stover or bean stubble, with that order being our preference of use.  Because we are a feeder-farmer industry we have to try and maximize the return to the farm, the feedlot, and the animal.  We have been using a lot of corn earlage, ensiled at 60 to 65% dry matter, instead of silage at 30 to 35% dry matter.  This switch reduces the number of loads of feed in a 3,000-head yard by one or two loads per day which saves time and money.  It is also agronomically better as we leave the organic matter on the field where we might short-term graze it or simply reduce erosion and improve soil fertility.

There is not a lot of University research data concerning earlage feeding, but it has not negatively affected our performance or COG figures in the six to eight years we’ve been doing it.  It improves pen conditions because we have a dryer stool.  We also don’t reach a physical intake fill before we achieve maximum caloric intake.

As we enter calf season, we can all help ourselves be more successful by emphasizing communication between feeders and pen checkers.  We feed them faster than we can check them so small things like a feeder telling the pen checker that “When I fed the new calves in 71, six to eight of them did not come to the bunk.  It was clean so they all should have been hungry”.  Just a comment that says spend a little extra time in 71 to make sure we don’t miss something before it’s too late.

A diverse offering but experience and observation are still the best teachers and these are pertinent things that are working for us.  Ethanol co products have challenged us to find different ways to paint the barn.