In response to the proposed changes, many questions came to the surface quickly: What are the new regulations? Why is this change occurring? Most importantly, how are the new regulations going to affect my calf feeding program?
Producers who had used milk replacers with NT for a long time – and in some cases, didn’t remember a time they hadn’t used NT – found themselves facing the question: What do I feed now? To answer that question, many producers have taken a step back and examined the most important things calves need to grow into healthy, productive replacement heifers.
For the past several years, NT has been approved for use in calf milk replacers to aid in the prevention and treatment of bacterial enteritis (scours). The approved use level of the antibiotic was expressed in terms of milligrams of antibiotic per gallon of reconstituted milk replacer solution. Under the previous regulations, a commonly-used inclusion rate was 400 grams of neomycin and 200 grams of oxytetracycline per ton of milk replacer. In addition, a milk replacer with these antibiotics could be fed continuously throughout the preweaning period, or as long as the calf was on milk replacer. This antibiotic combination was widely used in the milk replacer industry; USDA data indicates that 63 percent of heifers from 100-cow to 500-cow dairies were fed a medicated milk replacer. Research has shown that calves fed these medicated milk replacers grew faster with feed efficiency compared to calves fed non-medicated milk replacers. However, in regard to efficacy against bacterial scours, it is important to note that organisms other than bacteria (such as rotavirus, coronavirus and cryptosporidia) cause many of the cases of calf scours.
The new regulations call for NT to be fed at a 1-to-1 ratio and in proportion to the calf’s body weight. Two levels are approved under the new regulation:
• 0.05 to 0.1 mg per pound of calf body weight fed continuously for increased rate of weight gain and improved feed efficiency
• 10 mg per pound of calf body weight allowed to be fed continuously for seven to 14 days for treatment of bacterial enteritis caused by Escherichia coli and bacterial pneumonia caused by Pasteurella multocida
For a 100-lb calf fed 1.25 pounds of milk replacer powder, a milk replacer would contain 16 grams per ton of both neomycin and oxytetracycline for the low feeding level fed continuously, and 1,600 grams per ton of both neomycin and oxytetracycline for the treatment level fed for seven to 14 continuous days.
Clearly, the regulation changes affect how antibiotics will be fed to calves. The low level should not be fed with the expectation that the product will perform as well as the levels approved under the previous regulation due to the markedly lower feeding rate.
Calf raisers have two options. They can inventory two different milk replacers or utilize a Type B medicated feed (add-pack to be mixed with non-medicated milk replacer) in order to comply with the requirement that the treatment level can only be fed for seven to 14 continuous days.
What does this mean to the producer?
In addition to stocking two milk replacers or add-packs, producers may want to look at the many non-medicated additive options available. Here is a list of some of the most common additives found in the market. (Note: Some have more research support than others.)
• Yeast cell wall extracts such as mannan oligosaccharide (MOS) & beta-glucan
• Essential oils• Probiotics (i.e., direct-fed microbials)
• Prebiotics (i.e., feeds that promote the growth of beneficial bacteria)
• Organic trace minerals
While additives and medications can be very useful under certain circumstances, the basics of raising calves are always the foundation of any calf program. With the NT regulation changes, producers have taken this opportunity to evaluate their calf programs, determine what challenges they are facing with calves and then use the proper tools to overcome those challenges. More producers have placed increased focus on the basics of raising calves: provide high-quality colostrum in a timely manner, feed a well-balanced diet including milk, starter and water and provide dry, well-ventilated housing for the calf.
Timely feeding of good-quality colostrum is of the utmost importance to raise a healthy calf. Maintaining clean equipment and proper milking techniques start the process of good colostrum management. Once the cow is milked, test the colostrum for quality and use only high-quality colostrum for your calves. If you are not feeding colostrum immediately, the key is to get the colostrum cooled down and in the refrigerator or freezer. A warm-water bath of 120°F should be used to protect the quality of the colostrum when warming colostrum to feeding temperature.
It is recommended to feed calves at least four quarts of high-quality colostrum as soon as possible in order to achieve successful passive transfer. If you don’t have high-quality colostrum available, many excellent colostrum replacers are available on the market.
After colostrum, it is important to keep up those good habits. Feeding calves a well-balanced diet of milk and starter is imperative to raising healthy replacements. Remember, each operation is unique, but the goal is relatively uniform: double calves’ birth weight by weaning. Many calf programs are available to accomplish this goal. Work with your local calf and heifer specialist to help you determine what is the right program for your calves.
Also, take a look at the calf’s environment for the next eight weeks. Is it clean, dry and draft-free? Are the pens set up for easy feeding?
It is important that the calf be able to drink milk and water and eat starter without complications. As colder weather approaches, it is time to consider buffing up on those bedding skills and make sure calves have enough bedding for nesting. This will allow the calf to use energy for growth instead of maintaining body heat.
Even though the change in NT regulations has been one of the biggest changes to milk replacers and calf programs in the last decade, many producers will use this as an opportunity to make their calf programs stronger by going back to the basics of successful calf raising. PD