AGRICULTURE

Winter feeding: Focus on the future

ff_admin
Farm Forum

As winter sets in around us, the majority of our feeding management still lies ahead for the year. Whether you are feeding stored feeds already or have been able to position your herd to graze well into the winter, how we manage our cows today can have dramatic effects on our herd productivity into the future.

We get into a certain rhythm with our winter routines, and feeding cattle or moving fences and cattle can become monotonous tasks. Approaching each day with a sense of purpose helps our mind stay focused on what we are doing and why we are doing it.

One perspective I like to use is that we have a unique opportunity to influence not only the next two calf crops, but also the long-term productivity of our herds, with the daily management decisions we make during the winter.

Calf Crop 1

The first calf crop being influenced are the calves that are growing inside the cows we are feeding. The impact of our feeding strategy on the calf crop in gestation works through the sharing of nutrients, ability of the cow to generate high-quality colostrum and developmental programming effects on the calf.

Everything our cows eat gets shared with their calf, and an insufficient nutrient supply during late gestation can result in reduced birth weights of calves. While sometimes we do wish for lower birth weights in our herds, reducing the amount we feed our cows in hopes of low birth weight would not be a good strategy.

Although we do get lighter calves and a similar number of live calves at birth, we also end up with more undesirable consequences. More cows have difficult births, more calves get sick, and more calves die prior to weaning when cows were nutrient-deprived while carrying a calf. My preference would be to feed cows to their requirement, intervene only when necessary at calving, and watch a calf crop grow and remain healthy until weaning.

Not offering our cows a good supply of nutrients also can impact the first milk that is so crucial for their calves. Cows in low body condition at the time of calving generate colostrum that has fewer immunoglobulin proteins that calves depend on to build their immune system, compared with cows in good body condition.

In addition, colostrum intake is very time sensitive. The sooner a calf can get up to suckle, the greater the transfer of immunity will be. Calves that are born weak or calves from cows that don’t get up right away have a greater chance of becoming sick later in life, compared with healthy, vigorous calves that consume colostrum within a few hours of birth.

Additional effects of restricting nutrient delivery on calf crop 1 involve developmental or fetal programming. The concept of fetal programming is that nutrition of a dam during gestation has lifelong impacts on the calf she is carrying. For example, impacts of protein supplementation to cows can include increasing gain and carcass weight of steer calves, and improving reproductive performance of heifer calves. Again, these impacts were only the result of a cow’s nutrient intake while she was gestating a calf.

We typically like sound economic considerations, such as investing in areas with positive return on investment. Putting a pencil to the impacts that fetal programming can have on a herd’s bottom line is very hard, but it definitely is something we should not ignore.

The final note I will mention about the impacts our feeding management can have on calf crop 1 is the timing of feed delivery. If your management includes delivering feed to cows during the calving season, you can influence when calves are born. Feeding cows in the evening rather than in the morning can result in more calves born during the daylight hours.

Whether having a greater proportion of calves born during the daylight hours actually saves more calves is still up for debate. However, monitoring the herd and knowing when to assist with calving sure is a lot easier in daylight.

Calf Crop 2

The second calf crop that we are influencing now is the one that has yet to be conceived. The breeding season may seem like an unspecified time in the distant future, but we currently are laying the foundation for our herd’s reproductive performance next spring/summer.

We all have seen thin cows around the time of breeding. We also all have heard Doc call these thin cows open at the time of pregnancy checking. Alternatively, we have waited patiently through our calving season for those same cows to calve only to realize that they certainly would not be blessing us with the birth of a calf.

The association between thin cows at breeding and poor reproductive performance is very clear. However, thin cows at breeding many times can be associated with cows that were thin cows at calving, which can be tied back to how we manage our cows today.

With the energy demands of milk production being a thing of the past and demands for fetal growth still relatively low, thin cows that recently parted ways with their calves are prime candidates to gain body condition back easily and efficiently. From an energy standpoint, the time immediately after weaning is by far the easiest time of the year to put body condition on cows.

As we move from mid gestation to late gestation, putting body condition on thin cows becomes more difficult. The time of greatest fetal growth is during late gestation, and nutrient demands of our cows increase as a result. In addition, as a calf continues to grow, it also continues to occupy more space inside of the cow. This results in less space for food and, therefore, a need for feed of higher nutrient quality.

An immediate need for greater nutrition is present at the time of calving due to the immediate need to produce milk. So great is this need, in fact, that a lot of cows experience a time where they cannot physically eat enough to keep up with their body’s demand for energy.

The end result of this phenomenon is that cows begin to use their body fat stores for additional energy. The condition is called a negative energy balance, and the characteristics we observe from a management standpoint is that our cows lose body condition.

The goal of a good nutrition program is to minimize this loss in body condition immediately after calving. Trying to put weight on cows after calving is very difficult, and cows that are thin after calving simply may not have enough time to put on sufficient body condition to reproduce successfully early in the breeding season.

With all that said, if we have thin cows, now is still the best time to put on body condition, and this ultimately will impact the proportion of cows that become pregnant with calf crop 2 next breeding season.

How do we proceed? Evaluate the feedstuffs we have on inventory for our cows, determine whether we will meet their needs and develop a plan to target specific feeding strategies for specific stages of production. In addition, as you walk out to start the tractor today to feed, make plans to move the temporary fence in the stockpiled forage or get out to check on the cattle in the corn residue or cover crops, be ever mindful of how our management decisions today are impacting the productivity and profitability of our operations tomorrow.