New Discoveries to Head Off Health Setbacks in Transition Cows

A sick cow is a lost opportunity, according to Dr. Adrian Barragan, Associate Research Professor and Extension Veterinarian at Pennsylvania State University. “If an animal gets sick, it’s already too late,” he declared. “We can treat her, but she’s already got impaired performance.”

Barragan was trained as a veterinarian in his native Argentina before moving to the U.S. in 2012. Since then, he has devoted much of his career – in his PhD studies and now as a university researcher – to investigating how systemic inflammation in dairy cows can be modulated, particularly in the transition period, to prevent fresh-cow illnesses and production setbacks.

On a recent episode of The Dairy Podcast Show, Barragan shared key learnings of his research to date. Initially, he and others searched for a “blanket” approach that would be simple to implement, like administering an anti-inflammatory drug to every fresh cow. Unfortunately, they found the solution is not that easy, and Barragan said some cows don’t need such an intervention.

Barragan is interested in fine-tuning the selection criteria of the candidates for treatment, because he suspects there is potential damage in the simple act of restraining and handling them. As opposed to the “high-touch” fresh-cow protocols of previous decades that may have included tasks like daily temping and drawing blood samples from every cow, he is an advocate fewer touches to reduce unnecessary stress in transition.

As evidence, he cited an association discovered in his research. Cows that became ill in the first 60 days in milk were found to have higher cortisol levels 24-36 hours post-calving. He said this could be an indication that restraining stress could actually put fresh cows at greater risk of becoming sick later.

So, short of a cow-side test, how can cows be identified that actually need therapeutic transition support? Barragan said three key groups they have discovered will benefit from anti-inflammatory therapy are: (1) primiparous (first-calf) cows; (2) over-conditioned cows with a body condition score (BCS) of 3.75 or higher; and (3) cows that experienced dystocia.

Podcast host, Dr. Gail Carpenter, Dairy Extension Specialist at Iowa State University, commented that BCS presents a bit of a “chicken-or-the-egg” scenario. Is it the elevated body condition itself that contributes to postpartum inflammation and potential illness, or the factors that caused the cow to become over-conditioned in the first place? She also noted that routine body condition scoring and getting those values entered into herd management software is a challenge on many dairies.

Barragan agreed, but said he is encouraged by the progress of camera technology that has the ability to automatically assess and record BCS in on-farm settings like the milking parlor. “I think in the near future, we’ll have a little more accurate data on BCS parameters,” he stated.

Beyond those three basic categories of animals, the researcher hopes to develop additional selection criteria for cows at risk of higher levels of inflammation, based on herd records. Potential examples include cows with high somatic cell counts at dry-off, or those with lameness in the dry period.

Much of Barragan’s research has utilized acetylsalicylic acid as the inflammatory modulation treatment, administered in either one or two doses postpartum. He is also exploring the effects of prepartum treatment.

At the farm level, he recognizes it is sometimes a tough sell to promote a practice that produces the intangible result of cows not getting sick, especially when the “payoff” may stretch through most of the lactation. And at the same time, he finds those results exciting. “Even in one-dose studies, we are finding positive effects up to 150 days in milk, long after the treatment has left the cow’s system,” he noted. “That means it’s doing something molecularly at the cellular level.”

Aside from prophylactic, anti-inflammatory treatment, Barragan underscored the importance of other management factors that can have profound effects on transition-cow health and stress. They include:

•  Avoiding pen over-stocking;
• Ensuring that dry and fresh cows have at least 30 inches of bunk space;
• Avoiding commingling first-calf heifers with multiparous cows in the dry and fresh pens;
• Training dairy workers in low-stress animal handling practices; and
• Providing calving training to all maternity workers.

“Transition-cow health problems are the result of a multifactorial cascade of events,” he stated. “We’re working to identify the ‘big players’ that can make a difference in ensuring transition success.”