In The Scientific Journals: Feeding Co-Products To Swine

My job requires a lot of scientific reading and occasionally that will spark an idea for a newsletter article.  The April issue of Animal Frontiers has a literature review article titled “Swine convert co-products from food and biofuel industries into animal protein for food.”  (R.T. Zijlstra & E. Beltranena.  Animal Frontiers.  April 2013.  3:48-53.) 

Alternative feed for cattle is a common topic of conversation locally.  Especially with the current drought limiting feed supplies and the rising cost of traditional feeds.  However, we don’t hear much about alternative swine feeds around here.  This is likely due to there being few swine producers in the area.  Still, there are many hogs in northeastern Colorado and they contribute greatly to an active feed ingredient market. Nationally, more than seventy-two percent of the costs associated with swine production are related to feed.

When the term alternative feed or co-product comes up in today’s society, people will often correlate that with distillers grains (dry or wet).  Yet, there are many other things that will fit within those descriptors.  Beet pulp, citrus pulp, whey, bakery waste, and flour millings are all common co-products that are fed to swine.  Even left over table scraps constitute co-products on some small scale swine operations.  One of my former students works for a company in Georgia that collects unsold produce from grocery stores that they then process and sell as livestock feed.  As stated by the authors of the previously mentioned article, “Behind every food product in the supermarket, there is a co-product.”  In many cases these co-products can be used as a feed source to create high-value/quality animal protein.  In doing so we can often reduce feed costs in the livestock industry and improve what scientists refer to as the Human-Edible Protein Balance (H-EPB). 

The H-EPB is an index value that represents the edible protein output that is produced per unit of edible protein input that was required to produce it.  Researchers report that the H-EPB for the US livestock industry in 2005 to 2007 was 0.53, on diets relying heavily on cereal grains.  During the same time, the Netherlands, relying heavily on co-products, had a livestock feeding H-EPB of 1.02.  The researchers suggest that improving the US H-EPB through the use of co-products in swine feeds will help contribute to both a more sustainable swine industry and less societal pressure against pork producers.

Traditional swine diets made with cereal grains and soybean meal are very consistent and are easy to create and feed.  Feeding co-products in place of these can create a wide variety of challenges; however, with proper management and attention to detail many of these challenges can be alleviated.  Following are some of the management items to be aware of and monitor when you do feed co-products to swine. 

The nutritive quality of co-products can lack consistency.  Producers using co-products need to be aware of this and closely monitor nutrient quality.  Additionally, co-products tend to be higher in fiber than the original feed that it was derived from.  This is especially true when wet fractionation was used in the process.  High fiber content in swine diets can lead to lower digestibility, poorer feed efficiency, and greater excretion of nutrients.  Therefore, when utilizing these alternative feeds the producer needs to be certain that the lowered cost of production makes up for the decreased efficiency.

A co-product that was made using a wet fractionation process may be sold as a wet product, like wet distillers grain.  This can be very good for feeding to swine in a liquid feeding system and can improve responses to some enzymes.  However, it can add feed transportation costs and shorten shelf life of the feedstuffs.  Many places will dry the product.  This has both advantages and disadvantages.  Beyond shipping and storage advantages, positive responses may be increased mineral availability and the inactivation of some anti-nutritional factors.  However, overheating or heating for too long of period can also damage proteins and the ever important amino acid called lysine.

When swine producers feed co-products in the diet, they need to carefully consider how they develop rations.  As mentioned previously, the co-products tend to be higher in fiber than did the original cereal grain.  They also are usually higher in non-starch polysaccharides and protein.  Due to these differences, the digestible energy (DE) and metabolizable energy (ME) systems that many swine producers use to formulate rations will overestimate the energy contribution of the co-product diet.  As a result, growth performance is reduced when co-product rations are formulated using the DE or the ME systems.  The net energy (NE) system is more successful at formulating co-product diets.

Many mycotoxins can form naturally on crops.  We often use a “solution by dilution” approach to feeding grains that have an active mycotoxin issue.  However, we want to be extra diligent when feeding co-products made from affected grains.  As an example, ethanol production will actually concentrate some mycotoxins within the co-product.  This is readily seen with aflatoxins, deoxynivalenol, fumonisins, and zearalenone.  When this occurs, pig growth and reproduction rates can be severely affected.  It is important to note that it is rare that this becomes a problem, but if mycotoxins are an issue in a particular year or location you may want to be aware of it.  Some residues in the crop can be similarly concentrated when a co-product is produced from contaminated grains.

Potential lower feed efficiency as a result of feeding some co-products has already been mentioned.  High fiber and polyunsaturated fatty acids (PUFA) in some co-products, like distillers grains and canola meal, can also effect the carcass.  In particular, dressing percentage can be lowered and the hardness quality of the pork fat can be negatively affected.  Some researchers suggest that distillers grains or canola meal should be removed from swine diets at least three weeks prior to harvest to alleviate these concerns.  On the other hand, it has been suggested that the inclusion of co-products in the swine diet that are high in omega-3 PUFA may deposit greater amounts of omega-3 into fat and yield a carcass with health advantages.

As you can see, there are a lot of things that need to be monitored and managed when feeding co-products to swine.  However, with strong management practices in place, this may be a rewarding way to increase sustainability of the swine industry, reduce societal concerns, and increase profitability on the hog farm.  Co-product feeding will not be for everyone but it definitely can have the potential to be a management asset on many swine operations.  The key is to make certain that lowered feed costs outweigh lowered production results.

Importance of Colostrum

With calving season in full swing, I thought it a good time to visit about the importance of colostrum. 

True milk, also known as mature milk, will be secreted by the cow within 24-hours post-calving.  However, the first secretions from the mammary glands following calving are called colostrum.  Its development actually begins early in the third trimester and it is accumulated over several weeks.

Colostrum should be yellowish in color and is very rich in both antibodies and minerals.  It is absolutely vital to the newborn calf.  The placenta does not allow for passive transfer of immunity from the cow to the fetus.  So oral ingestion of colostrum becomes the primary source for the newborn to receive its initial dose of antibodies.

When the calf is born, it has a very porous stomach.  This allows large proteins, like antibodies, to pass through the stomach wall with ease.  As the hours post birth pass, the lining of the stomach will gradually “seal up”.  This is called gut closure.  Maximum antibody transfer occurs in the first two hours after birth.  By 12 hours post-birth the rate of antibody transfer has reached its average rate.  The ability for antibody transfer will rapidly decrease after this point.  At 24-hours post-birth, the gut closure is nearly complete and most antibody transfer is now limited.

Failure of passive transfer is the term that is used when calves do not get adequate antibody transfer.  When the calf’s blood is tested, you want the immunoglobulin concentration of the blood to be 10 grams/liter by the time the calf is 24 hours old.  When the concentration has not reached this level, failure of passive transfer has occurred.  Research strongly correlates this failure with greater calf illness and higher calf mortality losses.

Colostrum should have an immunoglobulin concentration of at least 50 grams/liter.  With this quality of colostrum, it is recommended that the calf should receive at least 4 liters of the antibody rich fluid.  Two liters in the first feeding and 2 more liters before the calf is 12 hours old.  This should be the minimum requirement to allow the calf to rise above the failure of passive transfer threshold.

NDF & ADF Podcast

I have some new computer software to create podcasts.  I am attempting to place a podcast about NDF & ADF here; however, the blog template is not cooperating.  So this link may not work but I am going to give it a try.

Ammoniating Straw

As drought continues to wreak havoc on forage and crops throughout the region, the price of feeding livestock keeps increasing. Those in the animal agriculture industry are looking for feed alternatives and ways to lower their input costs. Recently, some producers have been asking about ammoniating straw in an effort to extend their forage resources. Ammoniating straw requires that anhydrous ammonia be pumped into a sealed stack of low quality forage and allowed to bind with the forage tissue. This is a process that was researched and came to be an accepted management strategy many decades ago; however, it is often only used in desperate times. Ammoniation requires added labor and supply inputs. It can also be hazardous to the environment, livestock, and producers if mismanaged. Additionally, as the spread between hay prices and anhydrous ammonia prices widens, the ammoniation option becomes less economically favorable.


It is important to point out that ammoniation does not improve the forage itself, but adds a non-protein nitrogen (NPN) source to the straw. In many cases, this should increase both the intake (17 to 18 percent) and digestibility (20 percent) of low quality forage. It is commonly accepted that the crude protein (CP) content of ammoniated forage can be 1.5 to 2 times greater than the same non-ammoniated forage, when the process is done properly.

There is a small range of forages that are acceptable candidates for ammoniation. Usually it is the grass family (wheat, oats, etc.) that make for suitable candidates. Their tissue is easily permeated by the anhydrous ammonia and binds with the moisture within the tissue. Ammonia hydroxide is formed in this process and becomes the NPN source. Legumes (alfalfa, beans, etc.) should not be ammoniated. They have a more complex lignin & fibrous carbohydrate structure that interferes with the process.

The forage being ammoniated needs to have a moisture content of 15 to 20 percent. Otherwise, the ammoniation process will not complete itself. Often, straws will have lower moisture levels than this. Water can be added to increase the moisture content but needs to be done according to research established guidelines. If done incorrectly, molds can form and ruin the modified feed source.

Nutrient content of the forage being ammoniated can also limit successful candidates. An initial CP level of 3 to 6 percent is recommended. Below 3 percent CP and there is not enough improvement to justify the expense of ammoniation. Additionally, research has shown the starting neutral detergent fiber (NDF) content of the forage should be from 70 to 80 percent. When NDF exceeds 80 percent, there is once again not enough economical benefit to justify the process. Forages that have better quality than 6 percent CP and 70 percent NDF often have higher free sugar content within the tissue. When ammonia interacts with these, toxic compounds can be formed; rendering the forage useless.

The actual ammoniation process is a slow procedure. The straw stack has to be prepped with anhydrous lines and sealed. Typically, it will take a couple of days to slowly apply the anhydrous ammonia. Application should only be done in daylight hours. In routine August weather you should expect the interior temperature to reach 160*F. This should allow the chemical reaction to occur over 7 days. Cooler September environments may take 14 days or more for the chemical reaction to occur.

Only about 18 to 25 percent of the anhydrous ammonia applied to the straw will actually become fixed within the tissue. The remaining ammonia will volatize and be trapped under the plastic. As the plastic is removed, this gaseous ammonia is released into the atmosphere and can be very dangerous to those individuals working around the ammoniated straw stack. Caution must be used when removing plastic from this feed source and a safety spotter should always be utilized.

Those readers wanting information about the application procedure or the mathematical equations that should be used in formulating your ammoniation plan may want to read “Ammoniation and Use of Ammoniated Low Quality Forages” (CL 382) in the Cattle Producer’s Library. It can be accessed online at http://www.ansci.colostate.edu/beef/info/cattlemanslibrary/382.pdf.

Anthrax: What to Know

A case of Anthrax has recently been diagnosed on a cattle ranch in northeastern Colorado. Upon hearing this, many livestock producers may have questions about it. Anthrax is not one of the livestock health issues that people readily think about. The last time it was diagnosed in Colorado was thirty-one years ago.


An anthrax case requires the “perfect situation” to occur. First, the Bacillus anthracis spore has to be present in the soil. The soil needs to have a neutral or slightly alkaline pH; the appropriate soil environment can sustain the anthrax spores indefinitely. Additionally, soil calcium needs to be within a specific range. Next, there needs to be an environmental stressor that initiates spore activity. This can range from extremely heavy rains to our current situation, severe drought. Soil disturbances, such as dirt excavation, erosion, or extreme livestock treading, can also enhance the opportunity for spore exposure and subsequent anthrax infection.

Any warm-blooded animal (including humans) can contract anthrax. Cattle and sheep tend to be more susceptible than other domesticated livestock. The signs can vary depending on both the species infected as well as the mode of transmission. Animals can ingest or inhale the anthrax spores. They can also become infected cutaneously through skin cuts or insect bites. In some outbreaks the first sign may be finding dead animals, as anthrax can kill quickly in acute cases. Other signs can include swelling around the head, muzzle, or tongue. Staggering, tremors, respiratory difficulty, and collapse may all be seen in less acute cases. In cutaneous cases, the area of entrance may be hot and swollen initially and later become cold and lose sensitivity. Dead carcasses resulting from anthrax infection may have bloody discharges from body openings. DO NOT HANDLE THIS DISCHARGE IF PRESENT! Rapid bloating and decomposition of the carcass may also occur in anthrax cases.

If you suspect an anthrax outbreak, you should contact your veterinarian immediately. Do not handle the carcass or any discharges from the carcass until advised to do so. The infected animal becomes a reservoir for the Bacillus anthracis organism and when exposed to oxygen the organism is readily sporulated and hazardous. An autopsy is NOT advised in anthrax cases. Once advised to dispose of the carcass, those doing so should wear protective apparel and no skin should be exposed to the carcass or its discharges. Your local veterinarian and the State Veterinarian’s office will advise you of protective measures once a case is diagnosed. Affected carcasses should be either burned on site or “deep” buried. The area will also need to be disinfected. The State Veterinarian’s office will consult with you on this. You will not want to drag the carcass off, as this can spread the range of the anthrax spores and contaminate a larger area for both current and future exposures.

The Cattle Producer’s Library contains an anthrax factsheet that can be accessed at http://www.ext.colostate.edu/pubs/ag/anthrax-guide.pdf. Additionally, the State Veterinarian’s office has posted information on their website at http://www.colorado.gov/ag. Again, if you suspect an anthrax case on your operation, do not hesitate in contacting your local veterinarian immediately. Be careful to protect yourself and other people from anthrax exposure. If you have other questions about anthrax, you can contact your Colorado State University Extension office, the Colorado State Veterinarian’s office, or your local veterinarian.

Early Weaning Can Help Hungry Beef Cows

As our 2012 drought continues cattle producers are beginning to be concerned about forage supplies and what potential supplements exist in the area. Many locations are running out of grass to graze and the options are lease pasture, sell cows, ship cows to another state, or buy feed. Hay is a hard commodity to get a hold of right now. Many hay producers shipped every extra bale they had to the South, when the drought was so severe down there last year. Now we have a shortage locally and what is available is very expensive. Corn at $7+ a bushel is not an option many want to utilize either. But instead of increasing inputs, have you considered decreasing cow nutrient demands?


Early weaning is an option that some producers may want to look at. Typically, lactation is considered to be the largest nutrient requirement for the beef cow. The heavy milking beef cow may utilize as much as half of her daily nutrient intake to produce milk. Even light milk producers can use one-third of her daily nutrient intake for milk production. This means that if we can wean the calf and dry up the cow’s lactation cycle early, we can lower the needs of the cow and effectively make her more efficient during the drought. In times of limited forage, early weaning research has shown that removing the calf improves cow body condition, calf performance, cow conception rates, and forage availability for the cow. There are a couple of disadvantages that have to be weighed against the positives. First, there will be added costs related to feeding the weaned calves for a longer period. Secondly, by weaning the calves early there is an increased need for health monitoring, nutrition inputs among the calves, and intensive management of the calves.

Whenever I bring up early weaning people want to know how early a calf can be weaned. That answer depends on management and calf behavior. If managed properly with the initial intent of early weaning, a calf can be weaned at three to four weeks of age. Typically, if it is a decision based on an emergency, like drought, I would suggest no sooner than two months of age. The rumen of a calf does not function when they are born. The young animal has to begin eating grain or grass on their own before the rumen begins to work. It will take about twenty-one days from the start of eating solid foods until the rumen papillae are developed and working correctly. So the key answer is early weaning can occur about three weeks after the calf is eating grass, hay, or feedstuffs.

I know that there are a lot of questions that a producer may have when they are considering an early weaning strategy. Many more than I can answer in a brief news article. If you want to discuss this more, feel free to call me at the Yuma County Extension office at 970-332-4151.

Consider What to Cull Ahead of Time

Many cattle producers do not like the idea of culling cows. Certainly, as animals age and may not be raising a calf anymore, it becomes a reality that every rancher faces. However, the idea of culling deep into a productive herd is an unwelcomed prospect.


As I write this, the entire state of Colorado is experiencing some level of drought. Precipitation has been slim for most of us. Additionally, evapotranspiration (ET) has been significantly higher than normal thus far in 2012. The loss of moisture through plant ET can be seriously detrimental to forage if soil moisture is not adequate. The combination of abnormally high temperatures, high winds, and low humidity; along with abundant solar radiation is magnifying the drought’s affect on plant production. If relief does not arrive soon, many ranchers are going to have to either begin supplemental feeding or look at removing cattle from the operation. It can be a very difficult decision to make. So I have to ask, “Have you thought about culling cows from your herd?”

Range management is a balancing act between grass production and grazing consumption. If we severely overgraze during drought, we can do long term damage to the grasslands that we rely on for a sustainable ranching operation. It may take five, ten, or even twenty years to heal this type of rangeland damage. A drought influenced herd reduction should be approached with a certain degree of strategy and planning. I’m talking about serious culling that may reach deep into the productive herd. This is a case where the ranch is sacrificing current herd/cattle resources that are replaceable to protect the fragile rangeland resources that are responsive, not replaceable. It is best to consider how you would approach a herd reduction before you actually reach that point. (As you read the through the levels of culling listed below, please remember that different ranches utilize different management strategies. Some readers may feel that certain animals described should have been culled prior to the arrival of the drought, but I have to write this article from the perspective of visiting with the least management intensive of operations.)

The obvious cull is the cow that didn’t have a calf or lost her calf. This cow is only costing the ranch this year, so she should be the first on the trailer.

Next, the animal that is going to require the most nutrition through the drought period with the least return should be culled. In most cases this is going to be virgin heifers. This group of animals has a requirement for the highest level of nutrition within the cow herd. They are growing and will be for the next two years. Replacement heifers are typically the hardest cattle in the herd to get bred and often have the lightest calves at weaning time. In other words, they carry some of the greatest expenses with some of the least returns. The ranch can worry about replacement heifers after the drought, when there is active forage growth taking place.

Now take a serious look at what you have left in the herd and score the cows. Many people will disagree with me, but I say that this is a great time to get rid of any mean cows or those that have a tendency to ignore fences. Current pregnancy status can be a useful decision tool, depending on how your calving/breeding cycle lines up with your culling time. Cattle that are not pregnant or are dramatically short bred compared to others may be candidates for culling. Score structure of the cattle. How are the legs and feet? You may consider walking them along an ally way one at a time to evaluate how they walk. Do they have all or most of their teeth? How do their udders look? Cow’s that are no longer able to perform and produce at the herd average should be considered potential culls. Remember, we sometimes get emotionally connected to the herd we have built and taken care of for years. It can be helpful to ask a couple of your trusted friends or neighbors to spend an afternoon with you scoring the herd.

Hopefully, this can get you to a point that available forage, supplemental feed, and/or hay can get you through the drought. However, we are not always that fortunate. If culling needs to continue, the ranch needs to evaluate their herd records at this point. On paper split out the cattle that have outperformed others and plan to keep this group. Likewise, sort out those that have performed poorly and add them to the cull list. Records that are good to use for these decisions can be pounds of calf weaned (205 day adjusted), cost of production per cow, and dollars per cow returned. If your ranch does not currently have a strong record program, body condition score (BCS) can be used instead. Cull all cows that are at a BCS 3 or lower. Then come back and cull those old cows and young cows that are at a BCS of 4.

The next step in a deep cull can be very difficult. At this point you are likely far into a productive set of cows. The standing recommendation, if you get this far into a culling situation, is to remove those cows that are 8 years old and older. Next, look at those cows younger than 4 years of age. In theory, what remain should be the most productive cows in your original herd.

Nobody wants to get this extreme in their culling of a cow herd. Ranchers spend years building a herd, increasing genetic potential, and developing a set of animals that provide the necessary cash flow for the operation. An established herd also has the advantage of cattle that know the terrain and local plant communities, allowing established cows to coach calves and new heifers. It can be devastating to disassemble that in the manner that I have laid out in the preceding paragraphs. However, in a drought emergency drastic measures may be necessary; especially when you consider the current cost of hay and supplemental feeds. Plus, today’s price of cull cows is more favorable than typical cow markets have been in the past. If you are concerned that continued drought may force you to sell part of your cow herd; sit down with your records and develop a strategy for how you may face that. Utilize some of the strategies that I have laid out here. Also consider visiting with your banker and/or accountant about how selling cows would affect your financial and tax situation. Watch for state or federal declarations to be made as a result of the drought. Sometimes these can allow for limited options that can help with the financial aspects of having to sell many cows unexpectedly. (Capital gains tax deferrals, low interest replacement loans, etc.) A drought influenced herd reduction may not be a pleasant thing to face, but developing a plan can help take some of the emotion and stress out of the decisions that have to be made when a deep culling is required.