In the beef business, that’s not always the case.

For many producers, we are right in the middle of a critical time of year; many of our cows are moving from the second to the third trimester of gestation. That’s not the ideal time to be making major changes to our nutrition programs. However, it is a good time to make sure you are putting your cows in the best position possible as they transition into the third trimester and subsequent calving season.

Producers often comment about the amount of feed a cow should get during the critical third trimester and “second-guess” themselves about very specific nutrient amounts. Getting caught up in myths or small details could be a detriment to your herd. For example, many feel you should limit the amount of protein or energy your third-trimester cows eat so the calf doesn’t get too big and cause calving difficulties.

Certainly, you don’t want to overfeed cows, but when 75% of calf growth happens in the third trimester, you need to make sure that cow is receiving optimum nutrition to produce a healthy calf. Research has well documented that short-changing any aspect of nutrition here has long-term negative effects.

I also hear producers question very specific nutrients, such as copper or selenium, thinking their cows might need additional mineral. When getting caught up in specific nutrients, you might be missing the bigger picture of providing balanced energy, protein, mineral and vitamin nutrition, thus putting your calves and future herd reproduction at risk. It’s well documented that shorting energy, protein, minerals and vitamins in cows (especially as we approach calving season) can lead to problems with calf health, vaccine response and breedback issues for the herd.


When I get into discussions with producers on these topics, I remind them to take a step back and to review the big picture. Here are a few tips of how you can take an assessment of the big picture as well.

Know your foragesTake a nutrient content inventory of your forages. Sampling your forages is an important step to understanding the relative nutrient value of ingredients available. This is especially important this year, where some parts of the country had excellent forages while others are of poorer quality. With that knowledge, you can make appropriate adjustments to your overall nutrition program.

For example, if some forage is higher in protein or energy but another source was lower, you can strategically feed to match the reproductive cycle of the cow, perhaps blending the two different sources to match their requirements. Identify those forages that contain at least 10% to 12% crude protein (CP) and 48% to 50% total digestible nutrients (TDN) or NEm of 0.52 to 0.55 Mcals per pound of dry matter.

You should also take an assessment of mycotoxins that might be present so you can take appropriate action to mitigate risks to your cattle. For example, producers in fescue areas often harvest endophyte-infected hay for winter feeding. Usually, infected fescue retains a toxin (ergovaline) that causes fescue toxicosis when harvested for hay. This also can cause winter feeding problems. Identify those forages that contain over 150 to 200 parts per billion (ppb) of ergovaline to be able to make the appropriate feeding adjustments.

Know your mineral programI know minerals with forages can feel like you are chasing your tail when your forages can be different from one day to the next. That’s why it’s important to have a good mineral program. Think of it like the foundation of a house that everything else is built around. A good mineral program supports good macronutrition.

By working with a nutritionist to develop your program, you won’t have to worry about specific nutrients. A well-rounded mineral program will cover the basics for you.

Know your herd healthHealth and nutrition go hand in hand. It’s important to know about any health issues that might affect nutrition. Work with your veterinarian to discuss any health concerns and to discuss timing of any upcoming vaccinations or treatments. Vaccination timing, for instance, can be critical.

I have observed this to have a dramatic effect on herd as well as calf health. More often than not, I have seen BVD have insidious effects on a herd. Discuss with your veterinarian which cattle – if any – get modified-live virus or killed vaccines. Make sure booster vaccinations are done in a timely manner, too.

Know your cow conditionIt is important to consider what cow condition is and will be at calving because it affects colostrum quality, calf health and breed back. Most herds should have the goal of a condition score 5 female at calving.

One condition score equals about 75 pounds of bodyweight, so the last trimester is a tough time to put weight back on the cow. At the very least, make sure the cows are gaining weight in the last trimester.

Know your femaleA developing heifer should be fed differently from a first-calf heifer that needs to breed back. The coming second-calf heifer may also need additional nutrition as well. Some producers even see benefits of feeding productive aged cows separately.

Understanding what those different groups of females require from a nutrient standpoint and feeding them to meet those requirements will help each animal be more productive.

While the change from one year to the next always feels like the right time to do an assessment on the topics discussed here, I recommend more regular reviews with your nutritionist and veterinarian so you can continue to improve your herd year-round. By doing those regular checks, you’ll be sure to keep focused on the bigger picture of health and nutrition for your cattle.  end mark

Randy Dew
  • Randy Dew

  • Beef Cattle Specialist
  • Provimi/Cargill Animal Nutrition
  • Email Randy Dew