Early Weaning as a Winter Management Tool

John F. Grimes, Ohio State University Extension Beef Coordinator & Dr. Francis L. Fluharty, Research Associate Professor, Ohio State University Dept. of Animal Sciences

The vast majority of Ohio’s calves from commercial cow-calf production are born during the first four months of the calendar year. While exact numbers are not available, the authors estimate through various surveys and post-meeting evaluations that roughly 20% of Ohio’s beef calf crop are born in the last four months of the year. There are many reasons that a producer chooses a calving season but we would speculate that tradition and convenience would be at the top of most lists.

There is no “magical” date that is best to wean calves. Traditional dates to wean for most producers fall around the seven months of age (+/-) mark. Adding incentive for this traditional weaning date is the fact that beef breed associations and performance programs standardize weaning weights to 205 days of age. However, calves can be weaned at a much younger age. Dairy producers wean calves at a very young age!

If you utilize a fall calving system, at this point hopefully most of the cows are bred and are nursing a healthy calf. If this is the case, congratulations are in order as you’ve cleared some important hurdles. However, those of us who have experience with a fall calving herd probably will admit that we are currently entering the most challenging time frame of this system.

In most cases, fall calving cow-calf pairs will be showing some degree of physical stress as we reach the mid-point of winter. This is particularly true for the winter of 2010-2011 as we have seen larger amounts of snow and generally colder than normal temperatures for the past two months in Ohio. Cows that have been nursing a calf for 3-4 months and receiving average quality hay may be starting to sacrifice body condition in order to meet the needs of her calf and help carry her pregnancy towards mid-gestation. Calves are nursing cows that have passed the point of peak lactation from their dams and may be slowing in their rate of gain. Reductions in body condition can show up quickly in first-calf heifers and older cows that are lactating.

What can the cow-calf producer do to avoid some of these shortfalls in animal performance? Many will choose to increase the amount and/or quality of hay being fed. This practice will have difficulty increasing Body Condition Scores (BCS) while the cow is lactating. Supplemental grain will certainly provide more energy than hay but is an expensive proposition given current grain prices. Creep feeding is an option but under the best environmental conditions it is not a very efficient practice in terms of the feed conversion by the calf.

Early weaning of the fall-born calf crop may be the best management practice option to help maintain BCS with the cows and achieve efficient gains with the calf. Several land-grant institutions including The Ohio State University have researched the practice of early weaning and have found it to be an effective management tool under certain conditions. Early weaning research studies have weaned calves at a wide variety of ages with many utilizing weaning ages of +/- 100 days of age. Again, there is no single “best” age to early wean.

Early weaning can provide some definite efficiency in terms of the use of harvested feedstuffs. Information contained in the 7th edition of the “Nutrient Requirements of Beef Cattle” from the National Research Council (NRC) indicates this fact. A 1,300 pound that is lactating will have a daily Dry Matter Intake (DMI) of approximately 10 pounds more hay than a non-lactating 1,300 pound cow. Using hay valued at $60 – $80 per ton, this is a feed cost saving on the cow of 30 to 40 cents per day. It should also be noted that it is much easier to positively change BCS in a mid-gestation cow that is not lactating.

Much of the hesitation associated with utilizing early weaning as a common management practice is based on the perceived cost of feeding the calf. Research has shown that the early weaned calf is much more efficient in terms of feed conversion when compared to creep feeding the same age calf nursing the cow. A producer that weans a calf at 100 days of age could expect a feed conversion of 4 pounds of feed per pound of gain or better over the next 100 days after weaning. Using a complete feed price of $400 per ton (an approximate figure given today’s volatile prices), it would cost 80 cents or less per pound of gain in feed costs. The same age calf consuming creep feed while nursing the cow would expect a feed conversion of 8 pounds of feed per pound of gain or worse during the same period. These figures indicate that early weaning can be a profitable practice even in these times of historically high feed prices given current feeder calf prices.

How do we feed the early weaned calf? Research at OARDC has shown that feed intake on stressed calves is severely reduced during the first week. Therefore, receiving diets for calves should be approximately 16-20% crude protein, on a dry matter basis, for the first seven days. The protein concentration used should be increased to the upper levels of this range with highly stressed calves that have very low feed intakes. After the second week, feed intake increases and the crude protein can be dropped to 16% of diet dry matter. After the calves reach their normal weaning age, the crude protein level can be reduced to 13-14%, since the cattle should be on full feed by then.

After cattle have reached approximately 1.5% of body weight in feed intake (dry matter basis), every other day the amount of feed offered should be increased. Increases should be no more than 10% of intake. High-concentrate diets require that calves are brought on feed more slowly than high-forage diets. Bringing calves onto feed more slowly will help prevent acidosis and reduce nutritional stress.

Soybean meal is normally the protein source of choice due to cost and availability, but using a source of rumen bypass protein such as blood meal, corn gluten meal or fish meal in combination with soybean meal is acceptable.

Feeding hay during the receiving period reduces the energy density of the diet. Intake is the main problem during this feeding phase. Therefore, a 70 to 85% concentrate diet should be fed to ensure the calves have adequate energy intakes (Remember that corn silage is approximately 50% concentrate and 50% roughage on a dry matter basis).

Early weaning is a practice that does require extra management and added facilities from the producer. However, in cases of stress from winter weather or production stress associated with first-calf heifers, early weaning can prove to be a profitable management tool for the producer.