Former heavyweight boxing champion Mike Tyson famously said, “Everyone has a plan until they get punched in the face.” While he was referring to strategy in the boxing ring, the same holds true for starting lightweight (sometimes called peewee) calves. Anyone who has ever started these little calves knows it’s not a matter of if but when and how hard you will get punched in the face. Generally weighing 250 to 350 pounds, the size and age of peewee calves often present unique diet and health challenges for producers.

Fieser brian
Beef Field Nutritionist / ADM Animal Nutrition

Calf prices have been driven up by extremely tight supplies of feeder calves, resulting from historically low cow numbers. These high prices, coupled with high interest rates, have pushed some calf feeders to buy smaller and smaller calves to try and maintain numbers without breaking the budget. Despite the inevitability of that punch to the face, it is critically important to have a good plan in place so the punch can be deflected to result in the least damage. When it comes to nutrition, we want to make sure our nutrition program makes the greatest impact we can offer.

Getting a good start

With these little calves, getting them on feed is one of the most difficult challenges. A calf this size doesn’t have a big appetite or a large, fully developed rumen, so the diet needs to be more nutrient-dense than rations typically fed to larger calves. Under normal circumstances, calves this size are still out on pasture nursing the cow and learning to graze and ruminate forages. Calf feeders producing these peewee calves have accelerated that process, and the ensuing stress can lead to that knockout punch.

Producers not accustomed to starting lightweight calves might be surprised at some of the recommendations for feeding these little calves. Despite their inherent challenges, these calves demand the same five essential nutrients as any other: water, protein, energy (fat, carbohydrates), vitamins and minerals. For these calves, it is recommended to avoid or minimize the use of fermented and ensiled ingredients such as silage or haylage and wet distillers grains. These feeds pose a couple of problems, the first being palatability, as these calves have likely never seen feeds of this type and may find the smell and taste to be off-putting. In addition, the wet nature of these ingredients makes it difficult to get the intake we are after on these little calves by taking up too much ration space with water.

Additionally, clean, fresh water should be provided at all times. The water supply is easy to overlook and, when not on point, may be the cause of many problems blamed on more visible nutrients. Total diet crude protein (CP) should be 16% to 18% (on a dry matter basis) while avoiding non-protein nitrogen sources and focusing on ingredients high in CP, such as soybean or cottonseed meal. Ideally, the high-quality protein sources will provide a balance of rumen-degradable protein (RDP) and rumen-undegradable protein (RUP). To reach the genetic potential of these calves, an additional source of bypass amino acids may be necessary to unlock growth beyond what can come out of their developing rumen. Energy requirements can vary with desired average daily gain (ADG) but will generally be in line with what would be typical of pretty aggressive growing diets with net energy for gain (NEg), measured in megacalories per hundredweight, in the low 50s and total digestible nutrients (TDN) in the low to mid-70s. To achieve this target energy, any of the typical grains can be utilized, such as oats, milo and corn. These small calves are capable of very impressive feed conversions when fed the right diet, and feed conversions around 5-to-1 are common.


The next stage

The secondary step of starting calves is to prepare them for the next stage of production. For calves that will stay in confinement, the higher end of grain inclusion may be desirable, while calves destined for a grazing setting may be better suited to the lower end of the target energy range. Meeting the calves’ protein and energy needs will use a large portion of the ration – and this, along with the underdeveloped rumen of these calves, dictates that often less than 25% of the ration will remain for forages. Forages must be sourced from high-quality and highly palatable sources, such as grass hay with minimal stem development, alfalfa or other quality types of forage.

Just like the ration, there is not a lot of room in the calves’ rumen for fiber, so what goes in needs to be very useful. Low-quality forages like wheat straw and corn or milo stalks should be avoided. Despite the low cost of these crop residues, they are not digestible enough to positively contribute to the diet of a peewee calf. To provide the highly digestible fiber needed, ingredients like wheat midds and soybean hulls may be more desirable and a better value than they often are in rations for older calves that have a rumen capable of more complex fiber digestion.

The rapid growth and challenged immune system of these calves calls for a highly potent vitamin and mineral supplement. Supplement composition should complement the other ingredients in the ration to correct imbalances and deficiencies of critical micronutrients and be the final piece in a complex puzzle. Ideally, the supplement will get the total diet calcium-to-phosphorus ratio around 2-to-1.

Additionally, highly available sources of critical micronutrients should be considered, such as chelated copper and zinc. Superior sources of vitamins are critical for immune support and antioxidant function such as beta carotene (a precursor to vitamin A) and naturally sourced vitamin E (higher bioavailability compared to synthetic E). The vitamin and mineral component of the diet is essential for proper immune system support and development, which is key in ensuring effectiveness of vaccines and even antibiotic treatment. In many cases, an immune system that has been compromised can still fight off secondary challenges when antibiotic intervention is needed, keeping treatments to a minimum and calf performance on track.

Non-nutrient feedstuffs

Because of the tremendous stresses these calves face, it is also a good idea to consider non-nutrient feedstuffs to help them cope. Feed-grade antibiotics can play a critical role in starting peewee calves. As with any feed additives, proper intake is essential for an effective response. Some antibiotics may require a Veterinary Feed Directive and make it necessary for a veterinary consult. Additionally, there are numerous plant extracts, pre- and probiotics, and yeast derivatives that may provide the calf with the support it needs to maintain good health. Care should be taken to ensure products have strong supporting research and come from a reputable supplier to ensure an efficacious response. Because of the challenges faced in getting these calves to start eating, another additive to consider in the ration would be sweeteners to stimulate calves coming to the bunk and learning to eat their new diet in their new environment.

These nutritional guidelines and recommendations, taken in conjunction with proper health protocols and animal handling practices, can ensure that the shift to handling lighter and lighter calves can lead to more punches deflected and defensed without a knockout.