Prepare for Late Gestation Nutrition 

By Rory Lewandowski, Ohio State University Extension Educator

Recently a first cutting hay test crossed my desk that had a crude protein value of 8% and a TDN level of 55%. This is similar to many first cutting hay quality results across the state. This hay will work for a mid-gestation cow under decent environmental conditions. It is certainly not going to meet the nutrient needs of a cow in late gestation. So, as a livestock manager what is your plan to meet the late gestation nutritional needs? Now is the time to prepare for those nutritional requirements.

As I thought about this topic, I went back to the handout of Francis Fluharty's presentation at last winters Ohio beef school that was entitled "Late Gestation and Early Lactation: The Most Important Stages of Production". One of the themes of this presentation was fetal programming. Essentially, late gestation nutrition sets up or programs to some extent how that developing calf will respond to its world after birth. There are long term implications, either to the detriment of the calf or to its advantage.

The majority of fetal growth occurs in the last seven weeks of gestation. That fetal calf needs to gain on average about 0.9 lbs/day during the last trimester. Colostrum production starts at about 6 weeks prior to calving. Nutrition affects the nutrient supply to the fetus and it affects the quality of colostrum. Falling short on the nutritional requirements of the late gestation cow is not a wise strategy if the goal is to produce a healthy calf that will grow well from day one.

In his presentation last winter, Francis Fluharty said; "If the cow, or heifer, is nutritionally deficient during late gestation, it can have long-term impacts on the calf's performance, as the number of skeletal muscle fibers is set at birth, and nutrient restriction during gestation can reduce the body weight of offspring, even out to 30 months of age."

So, what can be done to prepare for late gestation nutritional needs? Those needs are crude protein levels in the 9 to 10% range and TDN in the 57-60% range. That TDN requirement could get bumped up if there are adverse weather conditions. The first thing that should be done is to find out what level of nutrients your hay can provide. Collect a hay sample of your second cutting and later hay and send it in to a lab to get it analyzed. Hopefully it will test high enough to meet late gestation nutritional needs and that will be your plan.

If your hay test results are not favorable and they fall short of 10% CP and 60% TDN or if you don't have enough of this higher quality hay to get all the way through late gestation, then what do you do? Here are some suggestions:

* Remember that although we use percentages as our guide for nutritional needs, the cow eats pounds, not percentages. In other words, the cow needs a certain number of pounds of crude protein and pounds of TDN. Better quality forages allow a cow to increase its intake because the digestibility and passage through the rumen is faster as compared to low quality hay. So, limit feeding better quality hay rather than providing it free choice can help to stretch limited supplies while still meeting cow nutritional needs.

* A similar strategy is to feed smaller amounts of hay more often. This results in less waste and again stretches limited amounts of good quality hay.

* Going back to the presentation by Francis Fluharty last winter, grinding forage should be considered. Grinding forage can increase its digestibility 30 to 35%. This means that a hay that normally would only meet mid gestation needs could meet late gestation needs. This is because the cow can eat more of that forage when it is ground. Since cows need pounds of energy, eating more pounds of a lower energy forage can meet the nutritional pound target. Can you work with an equipment dealer to rent a tub grinder or can you purchase one with several neighbors?

* Another method provided by Francis last winter is the use of a feed additive to aid microbial enzyme production and digestion of forage. There are several of these products on the market.

Don't let late gestation nutritional needs catch you unprepared. Time spent planning and preparing now is time well spent.