Don’t Quit Now!

Jan 21, 2021

By Les Anderson and Jeff Lehmkuhler

Many things in life make sense on the surface. Mark Twain once said “It ain’t what you don’t know that gets you in trouble. It’s what you know for sure that just ain’t so”. A great example is using water to put out a fire. On the surface this makes sense but if it’s a grease fire using water is a huge mistake. Beef cattle production has several examples of this but reducing feed to late gestation cows is one of the most common.

On the surface, reducing feed to late gestation cows makes some sense; less feed, potentially smaller calf, fewer calving problems, and a smaller feed bill. Fewer calving problems means more calves, more potential revenue, and, on the surface, this strategy is logical. But, like many things in life, the logical “just ain’t so”.

Fortunately, a great deal of research is available to help us understand the issues with nutrient intake of cows during the last trimester of pregnancy. As a pregnant cow moves from the second to the third trimester, her energy and protein requirements increase. Much of this increase is due to supporting the pregnancy and supporting the growth and development of the calf. However, we forget that during the last few weeks prior to calving the mammary tissues are growing and colostrum is being formed requiring energy and protein. “Uddering up” is one of those signs we watch for as cows near parturition, but we pay no attention that it took some groceries to support that udder development.

Dr. Arnold discussed some of the health-related issues of under-feeding late gestation cows last month in Off the Hoof. Here is a paragraph from her article. “New research has identified the role of “fetal programming of the immune system” during pregnancy as a major factor affecting calf vitality after birth. In fact, the latest research has proven there is no safe time during gestation to “short” a cow of her nutrient needs (including trace minerals) that will not impact the health of her unborn calf. A nutritionally deprived cow will produce poor quality and quantity of colostrum, have less energy to deliver her calf quickly, and she can lose a substantial amount of weight during her lactation so she will be slow to rebreed. Calves born to energy deficient dams will have less of the brown fat needed for energy to stand and nurse and more will die.”

Researchers have compared under-feeding and over-feeding with on-target feeding and observed the following in under-fed cows:

Have smaller calves
Have less energy stored in their bodies
Have lower antibody concentrations in their colostrum and less nutrient dense milk
Higher rates of dystocia (calving problems)
Higher calf death loss
Take longer to resume estrous cycles
Have lower pregnancy rates in the following breeding season

To clinch the nail on feeding late gestation cows, Dr. Steve Loerch and coworkers at The Ohio State University went to the extreme and examined the impact of type of feed on calving and reproductive performance. They fed cows either a normal forage-based ration or a ground corn-based diet with both diets balanced to meet the cow’s nutrients needs. Cows fed strictly corn-based diet had larger calves by 5-6 pounds, but the dystocia rate was not impacted. Pregnancy rate and calf weaning weight tended to be higher in the cows fed the corn-based diets. These data illustrate that even feeding extreme diets, dystocia rate and calving problems are not impacted by late-gestation feeding.

Even if you are not intentionally restricting nutrient intake, you may be unintentionally. We know that a higher plane of nutrition can slightly increase birth weight, but we also know that feed intake drops prior to calving in cows. Combine this reduced intake prior to calving with feeding a hay that just meets maintenance needs of a dry, mid-gestational cow all the way through to calving, and you have unintentionally got her nutrient balance out of whack. Nutrient balance issues lead to losing body weight, more dead calves, and lower reproductive rates.

Forty+ years of data very clearly indicate that the logic of reducing feed to cows before calving is not a sound management plan. Calving performance, calf death rates, calf health, calf weaning weights are all negatively impacted by underfeeding cows before they calve. Saving that feed on late gestation cows is like throwing water on a grease fire . . . it just doesn’t work.

Source : osu.edu

Video: US Soy: Pig growth is impaired by soybean meal displacement in the diet

Eric van Heugten, PhD, professor and swine extension specialist at North Carolina State University, recently spoke at the Iowa Swine Day Pre-Conference Symposium, titled Soybean Meal 360°: Expanding our horizons through discoveries and field-proven feeding strategies for improving pork production. The event was sponsored by Iowa State University and U.S. Soy.

Soybean meal offers pig producers a high-value proposition. It’s a high-quality protein source, providing essential and non-essential amino acids to the pig that are highly digestible and palatable. Studies now show that soybean meal provides higher net energy than current National Research Council (NRC) requirements. Plus, soybean meal offers health benefits such as isoflavones and antioxidants as well as benefits with respiratory diseases such as porcine reproductive and respiratory syndrome (PRRS).

One of several ingredients that compete with the inclusion of soybean meal in pig diets is dried distillers grains with solubles (DDGS).

“With DDGS, we typically see more variable responses because of the quality differences depending on which plant it comes from,” said Dr. van Heugten. “At very high levels, we often see a reduction in performance especially with feed intake which can have negative consequences on pig performance, especially in the summer months when feed intake is already low and gaining weight is at a premium to get them to market.”

Over the last few decades, the industry has also seen the increased inclusion of crystalline amino acids in pig diets.

“We started with lysine at about 3 lbs. per ton in the diet, and then we added methionine and threonine to go to 6 to 8 lbs. per ton,” he said. “Now we have tryptophan, isoleucine and valine and can go to 12 to 15 lbs. per ton. All of these, when price competitive, are formulated into the diet and are displacing soybean meal which also removes the potential health benefits that soybean meal provides.”