Back in basic nutrition class, we were introduced to the concept of “first limiting nutrient.” Take a simplified example: if some calves were eating enough protein, minerals, and vitamins to support 3 pounds of daily gain, but only enough energy to support 2 ½, they would gain . . . 2 ½ lb a day. In this case, energy is the first limiting nutrient. My professors illustrated this with the image of a barrel with one stave shorter than the others – it could only be filled to the top of the short stave, limiting the barrel’s effective volume. But, as I think about it, barrels aren’t something most of us routinely encounter. A more up-to-date example might be having a cell phone with 4G capabilities, paying for a plan that supports 4G access, but being somewhere with only 3G service available. So the local service becomes the “first limiting” factor...and someone who uses their phone for more demanding applications than I do doesn’t get the speed they were hoping for.
A conversation at a conference a few weeks ago got me thinking about looking at this concept in a broader context. I was talking with friends who, like me, are professionally focused on helping cattle producers make their operations as profitable and sustainable as possible. We each work for companies that can provide products or programs that address specific needs or challenges, and we are all confident that we represent valid opportunities to enhance our customers’ businesses. But we’ve all found ourselves in situations where we didn’t – or where we knew we couldn’t – provide the kind of ‘bang for the buck’ being looked for. That’s because there was a “first limiting” management practice on the farm or ranch that needed to be addressed first.
I guess this follows the same line of thinking as ‘holistic management,’ but without the fancy name. What it boils down to is recognizing that not only are all areas of cattle production important, they are so interdependent that we can’t manage (or ignore) one without considering the relationships to all the others.
When cattle are sick, it probably doesn’t matter which efficiency enhancer we add to the diet, or how great their sire’s EPDs were; they still aren’t going to perform at a high level. Infections can place multiple roadblocks in the way of growth and reproduction:
• Energy and other resources are re-directed towards fighting disease organisms and mounting a multi-pronged immune response;
• Some diseases lead to specific losses such as abortions;
• Sick animals often reduce their feed intake;
• Absorption of nutrients from the feed that is eaten may be impaired.
It’s easy to see that an inadequate preventive health program can stand in the way of expected performance. A veterinarian who is familiar with the operation and local conditions is the best resource for developing a vaccination and biosecurity protocol that helps ensure that overall productivity isn’t limited by disease challenges.
Like infectious diseases, both internal and external parasites can sap valuable nutrients away from productive purposes. Heavily infested cattle eat less, absorb fewer nutrients, must fuel stress-related and immune responses, and have to repair damaged tissues and replace lost blood. If all that is going on, it is unlikely that adoption of any unrelated management practice is going to completely overcome the limits placed by the presence of high numbers of flies, worms, or other damaging pests.
This summer’s drought has brought the potential impact of environmental conditions home to many of the nation’s cattle producers. Heat, cold, mud, wind, and limited water quality and quantity can all add stress, increase maintenance requirements, and discourage feed consumption. Man-made components of the animals’ surroundings can both relieve or compound these problems. While much harder to control than diseases and parasites, environment can certainly become the factor that places the ceiling on potential performance. When that is the case, focusing on options like mounds, shade, misters, improved access to water, or windbreaks will be the best investment the operation can make.
When everything comes together, and cattle are healthy, parasite-free, and receiving a balanced diet in a low-stress environment, they can still only perform to their genetic potential. If the goal is for even faster gains, heavier weights, or more efficiency (and the resources are there to support this level of production), the right cattle need to be in place to accomplish that. On the flip side, large rapidly-growing animals need more inputs than their more moderate counterparts, and unless those can be provided economically, that genetic base is a poor fit. Unless the cattle fit the environment and the performance goals of the operation, the herd’s genetic makeup is going to be the major limitation towards desired progress
I began this discussion with a review of the ‘first limiting nutrient’ within a nutritional program. But the overall diet being offered to cattle can also be the definitive constraint on potential herd improvements. Cattle receiving inadequate nutrition can exhibit reduced response to vaccines, be unable to mount adequate immune responses, will not exhibit their full genetic potential for growth or reproduction, are unlikely to fully benefit from products like ionophores, and cannot effectively combat environmental stress. A balanced diet, potentially enhanced with any of a range of effective feed additives, is the foundation of a successful and profitable cattle enterprise.
All these areas are critically important in raising cattle. And adopting tools and practices that enhance any of them can be a good investment. But to get the best return on that investment – and to see the full expected response to that change – we need to be sure there isn’t another “first limiting” management practice that needs to be addressed first.