Building immunity in feedlot cattle requires a holistic focus that begins long before an animal reaches the feedlot. The foundation of immune function starts in the cow-calf herd, where the right combination of maternal nutrition and vaccination program sets calves up for lifelong health and productivity. This article explores the two critical aspects of immune function building – nutrition and vaccination – and why they are key to the success of future feeder cattle that will fuel the world.
Maternal nutrition: The immune foundation
Lifetime cattle immunity starts in the womb. A strong cow nutrition program lays the groundwork for calves to develop robust immune systems, giving them a fighting chance against disease challenges they’ll face throughout their life. If we short the cow herd on nutrition, there is a ripple effect all the way to the feedlot because early-life nutrition sets the foundation for these calves – and it starts in utero.
Feeding for maternal antibodies through proper nutrition is essential for producing high-quality colostrum, which calves rely on for their early immune defenses. Colostrum is packed with immunoglobulins (Ig), which transfer passive immunity from the cow to the calf. A well-fed cow produces higher-quality colostrum, which directly impacts the calf’s ability to withstand pathogens from birth going forward.
Energy, protein and minerals serve as the cornerstones of a good maternal nutrition program. Deficiencies in these areas can lead to poor colostrum quality, reduced milk production and weaker immune responses in calves.
Cows of high health status and being fed an optimum plane of nutrition produce colostrum containing higher levels of Ig, thereby giving calves much-needed immune support the first few weeks of life. This allows those calves to be better able to fight off deadly scours-causing pathogens and other challenges while setting the stage for lifetime immune support.
Some postbiotic products can also be supplemented to the cow prior to calving to help support colostrogenesis, the process of producing high-quality colostrum. More specifically, research has shown that feeding a postbiotic beginning six weeks before calving resulted in cows whose colostrum yielded a 16% higher level of gamma-globulin. More importantly, the calves that nursed those cows with the higher globulin levels had blood immunoglobulin levels that were higher at 2 days old. Consequently, those calves would be better set up to defend against various health challenges.
Failing to meet a cow’s nutritional needs has far-reaching consequences for that calf throughout its lifetime. Underfed cows can not only produce weaker calves but can also depress colostrogenesis, thus depriving calves of life-saving antibodies from the start. Moreover, calves that fall ill early in life are more likely to get sick again, leading to costly treatments and lost performance later as they enter the feedlot.
Innate and acquired immunity
The calf’s immune system is comprised of two levels: innate and acquired. Both are essential to ensure the calf can respond to disease challenges and battle pathogens to keep energy channeled toward growth and performance.
Innate immunity: The first responder
The innate immune system responds immediately to threats. This “first responder” immune layer is influenced heavily by early nutrition provided via the cow and the first milk, or colostrum, after birth. While there is not a way to look at an animal and definitively gauge its innate immune status, body condition, vigor and energy level can all be indicators.
A calf with a sound innate immune foundation is better equipped to handle the transition from the cow-calf herd to feeding, where stressors like weaning, transport, exposure to pathogens and new environments can weaken their defenses.
Acquired immunity: The specialist
While the innate system reacts quickly with a rapid response, the acquired immune system is more specialized and relies on pathogen recognition to fight off specific invaders. This acquired immunity is the second prong of the immune system and must be built strategically with well-executed vaccination programs.
Vaccination timing for both cows and calves is critical. Animals should be vaccinated when they are in good condition and not already stressed. If vaccinations are given when calves are facing excessive stress levels (e.g., weaning, transportation, etc.) or their immune system is compromised, they may not be able to mount an effective immune response to the vaccine, thereby decreasing its efficacy.
Nutrition is a lifetime priority
As cattle move into backgrounding and the feedlot, maintaining their nutritional plane is just as important as in the cow-calf phase. High-quality feed, containing balanced levels of macro- and micronutrients, as well as a postbiotic product, can help prime the immune system and ensure the animal is resilient against challenges. This can help keep cattle out of the sick pen when respiratory or digestive pathogens might otherwise threaten the health and performance of calves.
Proper nutrition can also ensure cattle get the most out of their feed while maintaining digestive system integrity. The gut is an instrumental part of the immune system of any animal, along with the microbiome that resides within it. This is especially so in ruminant animals, where rumen fermentation is responsible for providing energy in the form of volatile fatty acids (VFA), microbial protein, B vitamins and other key nutrients. However, if we don’t feed a balanced diet with adequate fiber and micronutrients, rumen health may be compromised, leaky gut may become an issue or other digestive system problems may arise, which can lead to various health challenges of their own. Improving rumen health and performance with a targeted postbiotic product can aid in optimizing digestive health and immune function to thereby support overall health, performance and feed efficiency.
The payoff of a strong immune foundation
Building strong immunity in feedlot cattle pays off financially. Decreased health problems throughout the animal’s lifetime can translate into reduced treatment costs, fewer losses from death or illness, improved gain and feed conversion, along with less labor spent managing sick cattle. Research has even shown that carcass quality can be negatively impacted by cattle that get sick early in life.
When it comes to building an optimum immune response that lasts an animal’s lifetime, it takes:
- Maintaining cows on an adequate plane of nutrition while delivering key micronutrients to support innate immune function and acquired immunity
- Proper selection, timing and administration of cow and calfhood vaccines to ensure that the acquired immune system kicks in when needed throughout an animal’s life
- Reducing environmental stressors to help cattle maintain proper digestive health and immune function as they transition from the cow-calf herd to the feedlot
