Controlling Protein and Feed Costs for Dairy Cattle
Sharp advances in feed prices, particularly for protein supplements are of concern to feed manufacturers and dairymen. Adjustments should be considered in feeds and feeding to ease financial pressures.
Dairy farmers should consider limiting the use of whole-plant corn silage or other low-protein forages for dairy cows. Feeding primarily forage containing 16-20% crude protein on a dry matter basis may keep supplemental protein needed at a minimum. Often a finished dairy feed containing 12 to 16% crude protein (as fed) may be adequate compared to the need for a 18-24% feed when relying heavily on corn silage or other low-protein forages. Intensive grazing of young pastures attained by providing a new paddock every 1/2 to 1 or 2 days also can furnish cows with relatively higher protein and energy content than most stored forages. High protein alfalfa hay at $100-$130 per ton may furnish protein at unit costs similar to soybean and other protein sources.
Often a safety factor equivalent to 1% crude protein in a finished dairy feed is used in developing rations. Thus experienced nutritionists and dairymen with good production records might consider lowering protein levels moderately while monitoring response of the cows closely in terms of dry matter intake, milk produced and milk fat test. Problems with protein nutrition generally are more apparent during the first 60-90 days of the lactation. Lower dry matter intake, production and sometimes milk fat test may occur from improper levels of total protein and rumen degradable or undegradable protein. Adequate amounts of methionine and lysine also must be present in the diet.
Some research indicates that as little as 12.5-14.0% protein in the total ration dry matter may be adequate for good producing cows even in early lactation. Other studies indicate that the protein needs may be closer to 18%. These discrepancies indicate that proper protein allowances are far from being well established. It appears that the lower protein levels may be adequate when corn silage provides all or most of the forage dry matter and soybean protein provides the majority of the supplementary protein. In addition microbial protein synthesis must be at a optimum level via a well-balanced ration and good feeding practices. Thus protein intakes may be 85-90% of usual standards in some herds with little or no appreciable effects on response. The key to capitalizing on such a discrepancy lies in the ability of the feeder and his nutritional consultant to determine a practical level in an individual herd situation by closely monitoring dry matter intake and production when changes are made. Response to protein follows the law of diminishing returns. At current milk price and costs for protein supplements it appears that use of 15-16% crude protein in the total ration dry matter may be more profitable than higher levels for early lactation cows, even in herds responding well to an 18% level in the past.
Other steps that may be taken to ease the feed price situation include the use of urea or other non-protein nitrogen sources to replace part of the natural protein in the diet. The use of added NPN or urea is best suited to rations containing a high proportion of corn silage and dry grain. It is least compatible with a high haylage ration, especially if high-moisture grain also is fed. Urea may be included at levels as high as 1.5% in a finished feed if cows are fed a well-balanced ration. Mineral levels, including sulfur, usually need adjustment when urea is fed. Urea should be gradually introduced over a period of 2 to 4 weeks, starting at levels equivalent to .5 to .75% in a finished dairy feed. Do not use urea in a mixture with raw soybeans.
Wet brewers grains may furnish protein at lower costs per lb than most other by-product feeds or usual protein supplements. Wet brewers may be fed to milking animals at 20 to 40 or 50 lbs per head daily. It is important to keep some soybean, canola or animal protein source in the ration to provide adequate amounts of lysine, which is low in brewers or other corn by-products. Wet brewers should be considered largely as a wet concentrate, not a forage or roughage substitute.
Most by-product ingredients, at least dry ones, can be expected to fall in line with prices for soybean oil meal and soybeans. At retail prices soybean oil meal may furnish protein at a lower cost per lb than cooked beans. Look at unit protein costs or, better yet, formula costs in a least-cost but properly balanced ration before deciding to change protein supplements. Despite the lower cost per ton or cwt, some by-product ingredients may be more costly sources of protein. For example 26% distillers might be providing protein at $.38-$.44 cents per lb versus $.34-$.35 cents for soybean oil meal.
Dried brewers or corn gluten feed may be more favorable priced than other mid-protein ingredients. Alternative protein supplements to soybean oil meal or beans include canola from low toxicity rapeseed and cottonseed meal. Canola (38% protein) can replace all of the soybean protein in rations for dairy cattle since it has an adequate level of lysine and other essential amino acids. Cottonseed meal (usually 41% protein) has been satisfactorily used as the only protein supplement for dairy cows. Since it contains appreciably less lysine and methionine than soybean protein, it might be important to keep some soybean protein or animal protein in the ration if corn products are being used to provide more undegradable or rumen by-passable protein in a mix. It seems best to have at least .6% lysine and .2% methionine in a finished dairy feed. Thus the total cottonseed level in the ration (cottonseed oil meal plus whole cottonseed) should probably be limited to 35% of the finished feed for dairy cows. Because varying amounts of gossypol may be present in both cottonseed meal and whole cottonseed these ingredients should be limited to not over 20% of the total concentrate fed to calves under 3 to 4 months old. Gossypol is somewhat toxic to young ruminants and single-stomached animals. Older younger stock and adult ruminants are not adversely affected by gossypol. Cottonseed meal tends to produce firmer manure.
Peanut oil meal (45% protein) also may be considered. It is close to cottonseed meal and in lysine and methionine contents, but higher in fat at 5% than most oilseed meals. This should be taken into account if other high fat ingredients or products are used. Its use at higher levels may result in a laxative effect. Corn gluten meal (41% or 60% protein) is still another alternative. It is apparently less palatable at higher levels than most high-protein ingredients and contains relatively low levels of lysine. Thus it probably should not furnish over 55% of the supplemental protein or constitute more than 10-15% of a finished dairy feed.
Numerous animal or fish protein ingredients also may provide protein, especially rumen by-passable or undegradable protein at costs comparable to or less than soybean protein. These include fish meal (61-72% protein, blood meal (85%), meat and bone meal (50%), feather meal (85% hydrolyzed) and various blends of these ingredients. Due to their high undegradable protein content an intake of only 1 to 1.75 lb of these for high-producing cows should be considered in most cases. Fish meal with a high fat content (ex. 7.5%) often may depress milk fat test somewhat, particularly at relatively high intakes.
Care should be taken in making changes in protein sources to provide sufficient amounts of rumen degradable protein to maintain normal rumen metabolism and microbial synthesis of protein and other necessary items. Keeping soybean meal or cottonseed meal in the ration at levels equivalent to 10% of the finished dairy feed may help to do this. Urea also may be included in some rations high in rumen by-pass or undegradable protein at levels of .5 to 1.0% for this purpose. The expected rumen bypass or undegradable protein content of the entire ration should range from 35-40% of the total protein present.
If protein prices are high, it is strongly recommended that urea or liquid anhydrous ammonia be applied to whole-plant corn silage at ensiling. These NPN sources should be used at levels which bring the crude protein equivalent content of the silage to about 12-13% on a dry matter basis, not at higher levels. This means adding .15 lb of actual N for each 1% of dry matter present in the silage. For example at 30% dry matter, add 30 x .15 or 4.5 lb of N per ton of material ensiled. If urea with 45% N were used this would require the addition of 4.5 divided by .45 or 10 lb of urea per ton. If anhydrous ammonia at 82% were used this would be 4.5 divided by .82 or 5.5 lb per ton of silage. Preferably corn silage should contain 60 to 70% moisture for the addition of NPN.
The use of feed grade ammonium phosphate such as monammonium phosphate can provide a unit of phosphorus at a cost about 60% that for sodium phosphate and even less than some calcium-phosphorus ingredients. In addition NPN or crude protein equivalent is also being provided to help in meeting protein needs. While ammonium phosphates may contain as much as 62.5 to 105% crude protein equivalent, they are used at such a low level in meeting phosphorus needs that their NPN contribution to the ration is negligible. However they may be furnishing .4 to .8% crude protein equivalent in some finished feeds. The inclusion of relatively low levels of NPN might improve some rations, especially those containing high levels of rumen by-pass or undegradable protein.
Often corn prices advance more than those for small grains. Barley and sometimes feed grade wheat may enable considerable savings in feed costs if used properly in ration for dairy cattle. Oats generally are more expensive sources of nutrients than other farm grains. Since small grains contain more protein than corn, less protein supplement is needed in rations using them.
Other waste products such as candy, chocolate, starch, spaghetti, apple pomace without pressing agents, day-old bread or pastry, etc. also may be used to keep overall feed costs in line. Least-cost formulations and sound ration balancing are available from Dairy Science Extension at Penn State, some county extension offices and from numerous feed industry people and consultants. Now is the time to be making adjustments.
Source: Department of Dairy and Animal Science
