Hindsight Is 20/20 with Heifer Raising

Imagine how much better off you would be if you could know, with certainty, the outcomes of every decision before you made it. You would know who to bet on in the Super Bowl, which stocks to choose, the better tasting cheesecake, and many other important decisions.

While that may seem like fantasy, the reality is you can apply that approach today to your own operation. You already know the outcomes of your heifer raising decisions. Just look at your first lactation cows. The closer your heifers are to maturity when they have their first calf, at a reasonable age, the more productive they will be over their lifetime.

Start by looking at the end

Start with a goal in mind. Heifers should be well grown out and be at 85% of mature body weight soon (DIM<7) after they have their first calf, or 93-95% as a springing heifer (shortly before calving). So, if the average body weight of the mature cows in your herd is 1,500 lbs., springing heifers should be in the 1,400-1,425 lb. range.

From a production standpoint, mature first lactation cows usually produce 15% less than second lactation cows and 25% less than third and fourth lactation cows. Furthermore, week 10 milk of Lactation=1 animal’s is highly correlated with the average annual milk production of the whole herd (with Lact=1 at 38% of herd)

If the first lactation cows aren’t hitting those growth milestones, it’s time to evaluate the heifer raising program. To do that takes some math.

First let’s set some growth parameters. We know where we want to end up when heifers calve.  Assuming the goal is in that 1,425-pound range. An ideal breeding weight would therefore be 55% of their mature weight, or about 785 pounds.  Usually this frame/weight is achieved at 13-14 months, depending on the average daily gain (ADG) genotype and health of the animal.  Heifers double their birth weight by weaning, so assuming an average birth weight of 90 lbs, weaning weight would be 180 lbs at about 60 days old.

With those figures in mind, we can identify an ideal growth rate.

If we want to wean calves at 180 lbs and breed them at 785 lbs, that’s 605 lbs of gain. Here are the needed ADG targets for heifers to reach that ideal breeding weight by the month of age specified:

• 12 months: 1.98
• 13 months: 1.81
• 14 months: 1.66
• 15 months: 1.53

Obviously, heifers do not all conceive as soon as they are eligible, so the reproductive efficiency needs to be assessed on each farm to see how long heifers take to get pregnant. This would be the interval from entering the AI pen (AIDAT in DC305) and conception date (CDAT in DC305). This time frame can be factored into the equation. Now that heifers are pregnant, they need to continue growing to reach the goal at calving. Since the heifer is now pregnant the ADG will be different depending on whether the goal is springer weight or post-calving.  The calf, placenta and fluids make up about 150lbs (roughly 10% of body weight). Obviously, the heifer herself has the same body weight.  It’s just whether the end point is with/without uterine contents.

So, if the goal is a springer weight of 1425 lbs, and assuming the heifer did get pregnant at 785 lbs, that means she must add 640 lbs over the 280 days of pregnancy. This is an ADG of 2.28 lbs/day.

If a heifer calves in at 23months (700 days), she will need to average 1.9 lbs/day ADG from birth to calving (using springer weight).

Build a nutrition program

With those targets in mind we can go about identifying a nutrition and management program to make all this work. Here’s four simple considerations to get your heifers to where they need to be:

1. Start with colostrum. The creation of a healthy, productive heifer starts at birth with the delivery of adequate levels of high-quality colostrum as soon after birth as possible. Colostrum should be harvested from the cow cleanly and as quickly as possible after calving before the cow begins to reabsorb immunoglobulins. It’s well known that improved passive transfer results in healthier calves. You can understand how well your colostrum program is working by evaluating passive transfer of antibodies by measuring serum total protein. If your program is not achieving passive transfer goals, reevaluate the quality, quantity and cleanliness of colostrum delivery.
2. Be consistent. Calves, like cows, thrive on consistency. They should be fed the same product—either whole milk or milk replacer–at the same temperature, at the same time, every day. A water-soluble immune support product can be added to either whole milk or milk replacer to directly support the calf’s immune system and bolster rumen development. Because consistency is so important, complete a gradual transition from a milk-fed to a grain-fed diet over time.
3. Be clean. Any surface that comes in contact with milk in any part of the storage or feeding process should be cleaned and disinfected. Equipment used to feed calves should be cleaned and dried between use. Clean equipment and clean facilities go hand in hand. Clean bedding and fresh air can minimize adverse health situations. Starting with newborns, calves should be delivered in a clean, dry maternity area to minimize pathogen exposure. Use a blow drier on newborn calves to dry them off. When they move to individual housing, it’s important to keep bedding dry, especially in wet or cold weather. Allow for proper drainage around hutches to keep bedding dry. Consider calf jackets to keep calves warm. When calves move from the hutches to group housing, scrape and disinfect hutches between calves. Thoroughly clean and disinfect hutches at least annually.
4. Don’t forget about pregnant heifers. In many instances heifers, once they’re pregnant, are forgotten. While not much is needed to be done to heifers during this stage, heifers won’t reach their mature weight if nutrition is neglected. An important part of helping them reach maturity will be rumen development. Supporting optimal health and growth should include promoting a health balance of beneficial bacteria in the rumen. This means going beyond common grains and forages to include feed ingredients in the diet that balance immunity, promote digestive health, and enhance overall growth and performance.

It’s rare that you can see the outcomes of your decisions before you make them, but that’s the case with your heifer management program. Just by looking at your first lactation cows, you can determine if your heifer program is creating young cows mature enough to perform to their genetic potential. If that’s not the case, make the necessary adjustments to get heifers growing so they meet ideal growth benchmarks.

Editor’s note: The authors are Ruminant Field Technical Specialists with Diamond V. They can be reached via e-mail: kreed@diamondv.com and gstaley@diamondv.com. More information about Diamond V’s nutritional products can be found at https://diamondv.com