Part 1 of a 3-part series
1) Hoof trimming: An art lacking science?
2) Hoof trimming: Make the most of hoof trimming day
3) Hoof trimming: Prevent and treat lameness, with a purpose
Editor’s note: The following article appears in the April 2015 edition of Dairy Herd Management.
How is your foot wellness program designed? Are you in favor of the flat or angled trimming method? What’s your lameness rate and goal? Have you asked yourself any of these questions before? If not, today is a good day to start.
What kind of impact can poor hoof health have on milk production?
You may have heard it’s about 2.2 lbs. (1 kilogram) of lost milk per cow per day. However, making an assumption like that is difficult, especially when it’s the higher-producing cows becoming lame.
Gerard Cramer, DVM, DVSc
“When we try to assess milk production in lameness studies, it’s really hard, because we don’t know when the lameness started,” Gerard Cramer, DVM, DVSc, explained in an interview in his University of Minnesota College of Veterinary Medicine office. “There’s a huge amount of lag between diagnosis and when the actual event happened.”
Before asking the next question, we had to take in his office, which looks like a living library of hoof health. However, Cramer laments all the literature on hoof health fits on one shelf.
Next to his hoof diagrams and taxidermic cow foot models, Cramer has papers and journals related to dairy cow lameness. When he’s not reading, writing or researching, he’s tweeting as @dairycowfootdoc.
Cramer grew up on a dairy farm in the Netherlands and then Canada. He went to veterinary school at the University of Guelph.
“Basically because someone I said I had long arms,” he jokes.
While in vet school, his dad passed away, so he balanced becoming a veterinarian, managing his family’s dairy farm, and being a part-time veterinarian and a grad student over a span of 7 years, near Toronto. During veterinary school, he took a hoof trimming rotation with Dr. Jan Shearer and for his graduate work worked with Dr. Chuck Guard on a foot health project, spurring his interest in future research. The experience convinced him to re-focus his own future veterinary practice to emphasize foot health.
A practical education
However, even as a veterinarian, before he could teach hoof trimmers and dairy producers about hoof trimming technique, he had to learn the ropes of hoof trimming.
“There’s a difference between trimming a few lame cows, and picking up a grinder and looking like you know how to trim feet on 50 cows a day,” Cramer said.
After a half-year, he felt comfortable in a trimming chute, and then started training others. His lameness-focused practice started locally with veterinarians and farmers in Ontario, but it wasn’t long before word spread, and he was traveling to other provinces and states to give clinics or speak.
Missing the research and feeling comfortable with the technical side of hoof trimming, along with a broken finger that halted any hands-on technical advice,
Cramer applied for a job in academia at the University of Minnesota, and began building his lameness research program in June 2013.
Now that he’s settled in, Dr. Cramer is focused on finding a better way to prevent, diagnose and treat lameness.
Feet/leg wellness plans
He contends hoof trimmers are part of the equation. However, because dairy farms are so unique based on differences in flooring, walking, breeds and nutrition, they need to work with their veterinarian to create wellness plans for feet and legs, much like many farms have vaccination and mastitis protocols.
In Cramer’s mind, those plans go much farther than the trimmer. In fact, sometimes herds scored for lameness before and after a hoof trimmer does his job will be worse than when they started.
This might make you ask: “What am I paying my trimmer for?” Good question, and Cramer is set to answer it.
A public concern
Cramer sees lameness as the top animal welfare and public perception concern we’ve yet to do anything about.
“It’s not something we treat very seriously right now,” Cramer said. “We take more of an attitude that ‘lameness happens.’
“If you do a literature search on mastitis, you’ll see thousands of articles,” he explained. “For lameness, you’ll see hundreds. But when we start looking for experiment-proven treatments, we only have the first one coming out right now.”
Previous lameness studies have been done in an observational format, rather than the more definitive cause-and-effect style study.
“We have opinions, but not a lot of science,” Cramer explained. “Lameness is a disease we can control and manage for. We already know most of what we need to do to bring it to a manageable level, and we can move forward from there.”
“But the first question I want to answer is ‘How should we actually trim a cow’s foot?”
It seems basic enough, but there’s no universal answer.
Flat or angled?
In hoof trimming there are two styles, flat or angled. There are disagreements – mostly based on geography – on which is best and, with no science to support either side, the answer is up in the air. Europe almost unanimously favors the flat method, aligned with certification methods by officials. But in the U.S., the only certifier is the dairy producer, although Cramer suspects flat has a slight market share advantage over angled here, too. One book, “Cattle Hoofcare,” by E. Toussaint Raven, is known as the hoof trimming bible. Raven’s three-step method is what most trainers base their technique on – resulting in a flat trim.
“It’s based on plausibility arguments,” Cramer said. “If a cow’s foot is shaped like this, then we put her on concrete, and her weight transfers like this, so let’s trim in this manner. I don’t disagree with it, but it would be nice to know how much it reduces lameness and improves productivity.”
Cramer currently favors the flat method, but is quick to admit he has no data except personal observation to back it up. He leans toward the flat method after witnessing the effects of other methods in dairy herds. To gather data, he’ll be part of an upcoming 1,200-cow experiment with the Hoof Trimmers Association and American Association of Bovine Practitioners.
Even within his favored “flat” method, however, there are different variations for supposed extra comfort.
“But to convince anyone to do a method, twice a year, especially a large dairy, we need some data,” Cramer demanded.
How early and how often?
Studies do not tell us much about when and how often to trim. A few studies show trimming twice a lactation looks to be better than once. But due to the effects of different seasons and climates on hoof health, experiments done in Sweden might not translate to the Midwest, or Florida, or anywhere.
“There have been no good studies that say trimming should be done at dry-off and mid-lactation,” Cramer explained. “But that’s typically what we recommend, because that’s when lameness happens, leading some people to recommend trimming three times per year.”
Questions for your hoof trimmer
Before the next time your hoof trimmer arrives, Cramer suggested asking yourself a couple of questions:
• What’s the goal of hoof trimming?
• Why are we trimming feet?
“In my mind, the answer should be to prevent lameness and treat lameness, so anything that gets taken off the foot should meet those goals,” he said. “If your trimmer cannot explain why he is taking something off a foot, then it is time for a discussion about what we are taking off.”
The other logical thing to look for is results. If you are seeing more lame cows after the trim happens, there’s something wrong, and you should contact your trimmer and give them feedback, working with them to correct the situation.
During veterinary school, he took a hoof trimming rotation with Dr. Jan Shearer and for his graduate work worked with Dr. Chuck Guard on a foot health project, spurring his interest in future research. The experience convinced him to re-focus his own future veterinary practice to emphasize foot health. Cramer applied for a job in academia at the University of Minnesota, and began building his lameness research program in June 2013.
Hoof trimming tips
(for Holsteins – information provided by Zinpro)
• Measuring from front wall (below hairline to tip of toe) on inside claw of hind feet, trim any claw length longer than 3 inches for the average cow, 3.25 inches for large cows or bulls, leaving the toe end square.
• Claw length and sole thickness at the toe are directly correlated. Sole thickness should be measured at the tip of the toe where the cut was made. Anything greater than 0.25 inch in depth can be removed.
• Sole should be trimmed flat from front to back. Avoid removing horn from the heel of the inside hind claws. Be sure to leave a sole thickness of 0.25 inch at the tip of the toe.
• Don’t touch claws that are less than 3 inches in length or have less than 0.25 inch sole thickness. Typically in these situations, only the outside rear claw needs trimming to correct overgrowth and imbalance.
• Heel depth should be measured at the heel-wall juncture (outside of claw) from just below the hairline to the bottom of the sole. Only trim horn from the heel when this measurement is more than 1.5 inches.
Claw and heel balance
• A flat, weight-bearing surface between the inner and outer claws should be achieved throughout the trimming process. Caution: soles should not be trimmed so they flex under finger/thumb pressure.
• Evaluate claw and heel balance: hold front walls of both claws together and place a flat object across both toes, across both heels, and from toe-to-heel on both claws. No light should be visible underneath the flat surface for heel and toe-to-heel measurements.