Over the last years and especially the one most recent, the feeding industry finds itself almost overrun with alternatives and opportunities as commercial manufacturing and especially the evolving fuel industry makes available assortments of by-products that can and NEED to be fed as an alternative to the waste of this material in landfills and the like. One significant challenge for nutritionists and cattle producers is to determine the ingredients, additives and feed processing as well as delivery systems that will improve performance and/or efficiency of cattle on pasture. An important consideration must be that the program should improve forage utilization in a cost-effective manner in a given situation. While countless combinations exist for providing the necessary nutritional supplements, not all are as economical as we'd like. Others require substantially more labor to utilize than is available. One of the options the cattle industry has come to respect to accomplish both is that of liquid or molasses based supplementation. With the use of the new by-product some of which don't even have names yet it will become more cost effective to use less and less actual cane molasses. Many supplier countries of cane molasses are already seeing this commodity as a more valuable source of ethanol for use in automobile fuels. Let's take a look at some possibilities for these products as feeds or supplements for growing replacement heifers and stocker cattle.
A common goal of many beef producers across the country is to breed yearling heifers to calve at two years of age. Interestingly, across much of the south U.S., cattle production systems have at least two major differences from other areas of the U.S.
1) It is commonly known that forage nutrition levels of warm-season forages in the south are lower than those forages grown in cooler and/or lower rainfall areas of the U.S. This tells us that, more supplement is needed to grow heifers to meet the goal indicated above.
2) The use of some Brahman influence in most cattle reduces the proportion that reaches puberty by 14-15 months, i.e. Brahman crossed females take a bit longer to mature. This increases costs and reduces success so, in many cases, calving at two years of age is unprofitable.
To overcome these issues, producers are faced with added costs. These extra costs involve additional planting of annual forages, supplemental feeds, labor, facilities and supplies. Calving at two years of age requires a high level of management to be successful and profitable.
Nutrition is a key to successfully developing heifers and growing stocker cattle. Liquid supplements can be used effectively to supplement growing cattle fed forage-based diets. The challenge is designing liquid supplements to provide essential nutrients and additives that will improve performance at a reasonable cost. Let's examine several factors that must be considered.
Cane Molasses as a Source of Energy
Early research suggested that the feeding value of sugarcane molasses decreased when added at more than 10 percent of the diet. One study evaluated the net energy of molasses at different levels in beef finishing rations. The workers reported that in formulations containing 25 and 40 percent molasses, the net energy value was reduced by 49 percent when they were compared to feeding at only 10 percent of the diet. Another project suggested that molasses had a feeding value of 75 to 95 percent of the value of grain (i.e. processed corn) when added to the diet in smaller amounts. This value was reduced to 40 to 50 percent of the grain feeding value when added at higher levels. However, other, later studies indicated that the net energy value for finishing a steer did not decrease when molasses was added at levels above 10 percent of the diet. In more recent work it was concluded that most of the feeding data suggests the feeding value of molasses does not decline when added at 10 to 40 percent of the diet. What this appears to tell us is that when cane molasses is used at a maximum of 40% of the overall diet, no real reduction in feeding value is seen.
.The feeding value of molasses supplements compared to corn-based supplements in cattle fed forage-based diets has been examined on numerous occasions. One such study evaluated molasses-soybean meal and corn-soybean meal supplements fed at 1.1 percent bodyweight of supplement dry matter (DM) to newly weaned heifers grazing Bahiagrass pastures during the summer. Results over two years showed that both molasses-soybean meal and corn-soybean meal supplements increased gains 0.21 lb. for each pound of supplement total digestible nutrients (TDN) consumed. When molasses (72 percent TDN) and corn supplements provided similar quantities of TDN, cattle with free access to hay had similar increases in gain. Hay consumption was reduced to a similar degree by both the molasses- and corn-based supplements. This is a common effect seen during supplementation with grains or molasses since either of these are more energy dense than forages.
Cane Molasses Does it Have a Future in Cattle Feeds?
Interesting question. Based on what we know about where the ethanol industry is right now we might be asking the same thing about corn and the other grains in the not-to-distant future. We know that many high sugar or starch containing cereal product can be used as the primary agent for the distillation of ethanol a practice made popular in Tennessee, Kentucky and many other parts of the us as far back as the 20's and 30's. At that time it was more for entertainment or medicinal value as opposed to today when we consider it as one of our best options to overcome the fuel dilemma we find ourselves in. Can we get to a point where molasses, corn, grain sorghum, etc. are more valuable as fuel sources this is a definite possibility and depends on a long list of factors we don't have the room to cover here. That's another article topic. So should we be looking at liquid feeds that have little or no molasses inclusion? At this time my opinion is ABSOLUTELY. As mentioned before we have a wide variety of by-products that are available and that are coming available. A number of companies are aggressively developing products with excellent feeding values and economics that use little or no cane molasses.
However there are some things that need to be considered:
1) By-products are inherently variable. Be sure that your supplier is aware of this and that they are taking steps to overcome this variability such as buying from limited sources and not just buying based on least cost.
2) By-products can range in palatability. Suppliers need to have a good understanding of the effects these different by-products can have on palatability. This can have a great deal of influence on intake.
3) In many cases these products can be low dry matter, in some cases this can have a negative effect on stability of the product, especially if they are reporting high fat values. Fat and water generally are not very good bed-fellows.
4) Some products are marketed very inexpensively but have very little inherent intake control. Cheap feeds may not be so economical if cattle can eat uncontrolled amounts.
As we transition to liquids based more on by-products it will simply be necessary to be more careful of quality control and manufacturing issues and selecting suppliers that really do understand ruminant nutrition.
Protein Levels and Source in Liquid Supplements Must Be Considered
The crude protein concentration of sugarcane molasses is low (4 to 9 percent on a DM basis). Subsequently, it is necessary to increase protein levels in molasses-based products by one means or another. Remember from topics we've discussed in the past that one of the primary functions of feeding protein to cattle was to supply nitrogen to the bacteria in the rumen as well as the amino acids from protein to the animal itself. We term the protein fed to supply the nitrogen for the rumen bugs as degradable intake protein (DIP) since it is degraded in the rumen. Protein used to supply amino acids for absorption farther down the digestive tract are known as undegraded, escape or by-pass protein (UIP). In cow-calf and stocker production systems, a potential plan has been to meet rumen protein (DIP) needs first, then feed additional undegraded (UIP) proteins to meet protein needs of the animal when the response is economical. This means we need to develop a ratio of the DIP to UIP. Requirements for the DIP portion of the protein fed are generally met when the TDN to crude protein ratio is seven (or lower) to one for forage-based diets.
An interesting fact is that molasses from sugarcane grown on organic-matter rich soils has higher crude protein concentrations than molasses from sugarcane grown on soils low in organic matter. Since much of the molasses used in our feed industry is imported from other countries, it's difficult to make this assessment in advance. Higher crude protein values would indicate higher nitrogen levels in the product. However of all the nitrogen cane molasses, protein and amino acids usually comprise less than 25 percent of the total nitrogen found in the product. Also, the availability of the nitrogen in molasses for microbial utilization may be in question. One study in 1993 indicated that 75-85 percent of nitrogen in molasses was available to microorganisms. This is not hard to understand when we consider that up to 75 percent of protein in sugarcane molasses is in non-protein-nitrogen forms with most as DIP and very little (if any) UIP.
Liquid feeds are often fed to cattle grazing poor-quality standing pasture, range or crop residues. Nitrogen supplied by urea and other NPN sources is usually added to increase the low nitrogen concentrations in many molasses-based liquid feeds. In other words, to increase the overall protein content. Urea additions to increase crude protein in liquid supplements result in reduced consumption of liquid supplement at higher concentrations, which is usually desirable, and is cost effective. Urea is generally, however, not an economical means of limiting intake since other methods are available to accomplish this task. In most cases supplements containing natural protein from sources such as cottonseed meal or soybean meal usually give better results than supplements containing NPN from sources such as urea. Heifers offered molasses-urea blends may have lower performance due to lower consumption, but natural protein sources, such as cottonseed or feather meal, usually improve gains and pregnancy rates in heifers even if consumption and energy intake are similar. Growing cattle fed supplements containing NPN usually have better performance than heifers fed supplements with no added protein when the TDN to crude protein ratio is more than seven to one, but performance is often improved further when natural protein sources are used.
After DIP requirements are met, then UIP can be supplemented, if needed, to meet animal metabolizable protein requirements. A group of studies with growing beef cattle grazing warm season perennial grass pastures and hays has indicated that gains were usually improved when protein sources such as cottonseed meal, feather meal and blood meal were fed in or along with molasses-based liquid supplements. Feeding sources of less readily degraded protein to growing beef cattle improved performance and may be profitable in some beef production programs.
What all this seems to imply is that better performance is realized when molasses-based protein supplements and protein sources such as cottonseed meal, soybean meal or feather meal were used in combination and effectively meet the needs of both the rumen bacteria and the animal itself.
Fat and Feed Additives Effective in Liquid Supplements
Nutrient and non-nutritive additives that improve cattle performance have been studied and discussed extensively. Both fat and antibiotic additives appear to be beneficial in some production systems and delivery in self-fed liquid supplements (i.e. lick-tank products) has advantages over other feeding methods, if effective.
An easy way to increase the TDN concentration in liquid supplements is to add fat. Fats blend well in molasses-based feeds and are palatable to cattle. Fat contents in excess of 10 percent have been routinely used in some free-choice products without separation as long as a small amount of suspension agent is used. A number of recent studies indicate that fat may have beneficial effects on reproduction in cattle above their energy value. A significant number of these showed an average increase of 17 percentage units in pregnancy rate. Additionally, a number of these studies also showed an increase in milk production for these same cows. One theory suggests that the feeding of these fats increases hormonal precursors used in the reproductive process.