Inflammation is essential for fighting infections, activating the immune system, and repairing tissue damage. However, prolonged inflammation is costly for dairy cows, draining energy and nutrients that are critical for milk production, growth, and reproduction. Thus, managing inflammation is key!
Energy and nutrient costs of inflammation
When a cow eats, energy is first used for maintenance, then lactation, growth, and reproduction. Inflammation diverts resources, and acute inflammation can consume approximately 1 kg of glucose every 12 hours. Producing 1 kg of milk requires 72 g of glucose; thus, a 40-kg/day milk-producing cow needs about 2.9 kg of glucose daily. Inflammation severely reduces glucose available for milk yield and fertility. Inflammation also uses around 20 g of calcium every 12 hours. Since milk fever can be triggered by just a 5 g calcium shortage, this illustrates how easily inflammation can tip cows into metabolic disease.
Inflammation during the transition period
High levels of non-esterified fatty acids (NEFA), ketones, and low calcium are linked to transition disorders. Previously, it was thought that diseases during transition cause inflammation. New evidence shows inflammation itself is a normal biological event in this phase, often starting in the mammary gland, digestive tract, or from calving injuries. If inflammation is too strong or prolonged, it drives negative energy balance, elevated NEFAs and ketones, low calcium, reduced feed intake, and diseases like mastitis, milk fever, metritis, and displaced abomasum.
Managing inflammation
This raises a key question: Should inflammation always be suppressed? Inflammation is necessary for the immune response, but its duration and intensity must be controlled. Lessons from human health support this idea. During COVID-19, some children exposed to the virus did not fall ill and showed no antibodies. Their immune system relied on the thymus gland, which produces naïve T cells. With adequate zinc, these T cells multiplied and differentiated efficiently, favouring TH1 cells that rapidly attack pathogens. This allowed infections to be cleared quickly without needing long-term antibodies.
Implications for dairy cows
Similarly, dairy cows benefit from a strong, rapid immune response that resolves inflammation quickly, sparing energy and nutrients for milk, fertility, and recovery. Nutrition is central. Adequate zinc is particularly important for optimal T cell function, helping cows manage inflammation effectively, avoid transition diseases, and maintain productivity.
Conclusion
Inflammation is necessary but costly. The goal is not to eliminate it, but to support cows – especially during the transition period – with the right nutrition to strengthen immunity, shorten the duration of inflammation, and safeguard milk yield, reproduction, and overall health.