Forecasting performance boosts herd health
Farmers rely on weather forecasts to know when to plant, spray and harvest. Forecasting can also help predict poor health in the herd.
Jackson A. Seminara, Ph.D., presented “Forecasting Performance: How Clues from Blood, Milk & Sensors Can Predict Unfortunate Outcomes in Multiparous Cows” as part of Cornell’s “Boots in the Barn” series.
“The transition period is hard,” Seminara said. “We like to think of the transition period as an adaptive balancing act.”
Cows have to give milk while adapting to the needs of their recovering postpartum bodies. They may experience energy and mineral deficits, altered immune function and microbial threats to their health.
“Most dairy cows can manage this,” Seminara said. “That’s not the case for all dairy cows. Nearly 40% to 70% of all dairy cows will experience some form of early lactation disease.”
Cows who fail to adapt can experience lower milk production, lower reproduction success, disease and even death.
“The main point is to recognize cows that are failing to adapt early enough so we can do something,” Seminara said.
Accurate forecasting can help rescue the cow’s performance and promote overall heard health.
“If we are able to forecast performance at the herd level, we can get an idea of how our system is working,” Seminara said. “It can inform us on what to do next.”
In addition to the many clues that lab work can provide from blood samples, farmers can learn about their cows through measurable factors such as rumination, activity time and, potentially, information from the milk.
Blood analysis can look at biomarkers such as energy-related metabolites, calcium and inflammatory markers (haptoglobin).
“How much food is she eating and how much fat is she utilizing?” Seminara said. “Inflammatory markers are used as biomarkers to find out how well they’re doing and how well they’ll do.”
He called energy-related metabolites the “most historically well-studied biomarkers,” as farmers keep an eye on the drop in intake during the transition period.
“As a result of the drop in intake, most cows mobilize a good deal of fat from around the body and start ketogenesis,” Seminara said.
Beta hydroxybutyrate (BHB) is the name of the marker that shows how much ketogenesis is occurring.
“These processes are adaptive responses under regular circumstances,” Seminara said. “This is something that they do to meet the very high energy demands of producing milk. It’s not necessarily a bad thing unless things get a little bit dysregulated.”
A prospective cohort study of 1,164 cows was sampled for non-esterified fatty acids (NEFA) prepartum (-14 to -2 days) and classified based on cut point. The cows were followed through lactation.
“NEFA can be used as a potential forecasting tool about potential reproduction,” Seminara said. “It’s a very clear outcome. In the first test that was for BHB, the cows were more likely to have lower milk production through 30 days in milk.”
Sometimes cows with high BHB have higher milk production and that has been associated with overall higher milk production, which is confusing for farmers.
“This is adaptive and for some cows – it may be healthy for higher BHB,” Seminara said. “They can use all the energy sources available for them. Cows that are adapting poorly can’t use those energy sources.”
Milk fever can represent an immediate, lethal danger to cows unless they’re treated with an IV of calcium. But with effective prepartum diet and strategies, “we’ve effectively reduced incidences to 5%, which makes it something we’re not too concerned within in modern dairy farming,” Seminara said.
Cows’ mammary glands can uptake calcium from the blood and put it in the milk.
“Unfortunately, not all cows can do this,” Seminara said. “Those that don’t normalize this by four days in milk have poor adaptation.”
Dyscalcemia is when the serum total calcium concentrations are lower than 8.8 mg/0.1 L at four days in milk. This happens to around 30% of dairy cows, although “we’ve seen it get much higher on certain farms,” Seminara said.
It’s associated with early lactation disease and a good indicator of poor adaptation, as well as linked with poor reproductive success.
“I’m not saying there’s a causal association,” Seminara said. “We don’t know if dyscalcemia is predisposing these cows. Dyscalcemic cows are producing less milk for a long time. It’s not a little bit less milk; it’s quite a lot” – it can equal more than 10 lbs. of milk daily.
Most dairy cows experience an increase in inflammation during the transition period as an adaptive response under normal conditions for tissue repair, placenta expulsions, uterine involution and host defense. Haptoglobin is a useful marker of inflammation.
Keeping an eye on inflammation can help farmers tell whether a cow is healthy or beginning to falter in her health as the inflammation goes out of control.
