Preparing calves for a healthy future starts at birth, but summer heat brings challenges that can impact the lifetime health of newborn calves. Data indicates that heat stress can negatively impact antibody levels being passed along by the dam, compromising the calf’s immune system.

Researchers studying immunity at the University of Florida found that calves from heat stressed dams had significantly lower serum immunoglobulin-G (IgG) levels from birth through 28 days of age, compared with calves from non-heat stressed dams. Another study found that heifers that experienced heat stress in the last three weeks of gestation produced colostrum with much lower IgG concentration.

To successfully obtain passive transfer and provide the calf with protection from diseases, calves need to consume a minimum of 150 grams of IgGs. If calves don’t receive that level, they may not be adequately protected.

“Antibodies, also referred to as IgGs, are imperative to protect newborn calves from the pathogens that cause scours,” says Bobbi Brockmann, calf specialist and vice president of sales and marketing for ImmuCell Corporation.

Brockmann adds that producers can combat the potential impact of heat stress on antibody levels by planning ahead to give calves the immediate immunity they need for long-term success.

“If IgG levels are compromised, or producers are unsure of the levels, it’s crucial they give their newborn calves a USDA-approved antibody product within the first few hours of life,” says Brockmann. These products have a consistent antibody level proven to reduce mortality and morbidity associated with common calfhood diseases such as E. coli and coronavirus.

With the rising temperatures can also come a rise in bacterial growth, exposing vulnerable newborn calves to more infectious diseases. By providing newborn calves with a USDA-approved antibody product, producers can provide their calves the immediate protection they need during the hot summer months when immunity is likely to become compromised.

To get summer-born calves off to a healthy start, and protect them from increased bacteria loads, don’t leave their immune system to chance. Evaluate your newborn calf program today to ensure your calves are receiving the protection they need.

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