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The Limiting Factors in Livestock Production- PROTEIN

If you are building anything as complex as a cow, or even if you are building Model-T automobiles, you can only build as much or as many units for which you have 100% of the parts. In the latter example if you run out of, say, steering wheels, then Mr. Fordʼs innovative assembly line stops until more parts can arrive. The missing part, the one you ran out of first is also called your “limiting factor”. Once more steering wheels arrive, production continues until the next snag, the next limiting factor is achieved.

With livestock, the main limiting factors often boil down to the Big Three, Energy (carbohydrates, sugars, starches), Protein (the 22 essential amino acids, e.g. the building blocks of all protein), or, last but not least, Minerals. Minerals make the list because it takes minerals to generate everything, including Energy (ex. Phosphorus to run the Krebʼs Cycle in the Mitochondria), and Protein (ex. Sulfur to build all the essential amino acids). Some soils and forages exist on areas of the planet where there have never been adequate levels, whereas most “farmed-out” soils have lost their native mineral storehouse.


When it comes to protein production within the grasses, forbs and woody shrubs, the soil, air, water and microbes combine to manufacture protein. The key element in all protein is Nitrogen (a mineral). The air we breath is 78% pure nitrogen but itʼs in the N2 triple-bonded stable form as a gas and neither plants nor animals can directly access it to make nitrogen, which is a real shame. We have to go all over the planet, even get into wars and spend a lot of diesel to make what we call “synthetic or artificial” nitrogen, mostly anhydrous ammonia. A German chemist named Fritz Haber won the Nobel Peace prize for developing the technique to make it directly from the air. Another German Carl Bosch also won the big prize for commercializing the technique into commercial scale. They say that 1/3 of the total earthʼs population is here because of this invention. Half the protein eaten by humans is made from artificial ammonia. Since the Germans couldnʼt make beer out of it they converted it into explosives and during WWI the Allies had access to Chilean saltpeter to make bombs whereas the Germans had their home-made nitric acid.

The natural source of just about all available nitrogen is from microbes. We have landers on Mars but no one yet knows exactly how the tiny and apparently very complicated mycorrhizal fungal organisms split the nitrogen gas and insert it into the rootball of legumes but letʼs just say we wake up in the morning and there are the presents under the tree. Just about everything else in the plant, 98% of the plant anyway is made from the air via the process of photosynthesis, wherein the plant combines sunlight, CO2 and H2O and forming tens of thousands of complex compounds that make up life. Less than 2% of a plant comes from the soil, but it is an essential ingredient without which plant life cannot exist for very long.

Due to “limiting factors” all sorts of forage plants in certain areas from Mexico to Canada and across the span of North America are too low in protein to be adequate nutrition. Books are written about techniques for ratcheting up protein levels in deficient plants. Not the least of which of these techniques would be the introduction of legumes, known as “nitrogen-fixing plants”. The indigenous “Three Sisters” style of paleo-agriculture grows squash, beans (nitrogen fixers) alongside maize (corn) for a full complement of amino acid profile in adequate levels for full nourishment. Plants that fall below 7% crude protein are considered “low quality” forages, when it is from 7-9% it is considered “average quality” and plants that exceed 9% are considered “high quality”.


It is required for replacing the daily loss of body tissue, it is necessary to maintain pregnancy and grow the next generation but itʼs also required in the rumen so that the trillions of microbes there can digest fiber and other foodstuffs. When protein intake drops below the “limiting factor” level itʼs quite noticeable, body scores drop, feed costs skyrocket, the calf crop is weaker, lighter and sicker. Milk production drops off the chart.

The protein requirements for spring calving cows hovers around 6-8% for most of the year, surging upwards to 10-14% in the spring. Most of the typical forage plants also rise in protein levels beginning in spring, peaking throughout the hot summer months and then taper off to very low levels.

Itʼs very important to realize that the Degradable Intake Protein (DIP radically affects the digestibility of Neutral Detergent Fiber (NDF) or the energy from the plant. Low protein, that is low-quality forages with less than 7% crude protein are only about 40-45% digestible whereas when the DIP is increased to even .# a day, the digestibility goes upwards to the 55-60% range. The Undegradable Intake Protein (UIP) aka “bypass protein” is unaltered by the rumen microbes and passes directly to the small intestine where it is worked upon in a similar manner to how we break it down into food. Adding Apple Cider Vinegar can add another 20% increase to NDF digestibility as well. In addition, cows that have adequate protein will always consume more dry matter, thus becoming more productive.


For almost all cow-calf operators the cost of feed is the greatest expense in raising a weaned calf. When protein is low, the augmentation sources of protein vary in cost and quality with quite a bit of correlation between the two, meaning, as usual, you get what you pay for. Some of the cheapest sources actually come with risks and dangers that can take multiple generations to undo. Here are the main categories….

1) NATURAL- Alfalfa or other high-quality “dairy” hay or pellets- This is one of of the very best, but also not without risks. We now have to factor in the high likelihood of being contaminated with Monsantoʼs GMO alfalfa and the plant itself has detrimental features, seen in almost all legumes when fed in excess, that of being thyro-toxic and excessively estrogenic (plant phytoestrogen content). Itʼs also very expensive, especially during times of drought with low supply and high demand. For many producers this option is unobtainable due to cost.

2) CO-PRODUCTS- Ethanol Waste or Dried Distillerʼs Grain (DDG) lick tubs, cubes or blocks- This newcomer was embraced rabidly by producers because it seemed too good to be true. Super cheap (thanks to lavish government subsidies from beginning to end), high in protein, and widely-available. But, alas, it was too good to be true. When you have a product with GMO genetics, soaked in Round-Up and all the other antibiotics and chemicals required for ethanol extraction, topped with lots of mold, youʼve got a problem, Houston. Additionally, concentrated sulfur levels in DGDs may be too high, causing several problems including tie-up of copper, polioencephalomalacia (brain loss), or, more commonly, just going off-feed. The same problems can be found with Wet Distillers Grain (WDG) as well. All the distillery swill is cheap, but is it really? This same product, back in the 1800ʼs from whiskey production on the East Coast led to dairy herd health problems that eventually required mandatory pasteurization of the milk because it was so laden with disease. All this thanks to diet-related compromised immune health of the cows. Previous protein supplements made of animal products, such as fat, by-products, feathers, hair, or blood have also fallen out of favor or legality due to several perceived health problems as well as marketing issues.

There are also other safer co-products for protein supplementation such as Soybean Meal but recent penetration of GMO production makes it very unlikely to be from natural sources. The other common sources include cottonseed meal (GMO too but 24% CP), corn gluten (21% CP), rice bran (15% CP), wheat middlings (18% CP) or brewerʼs grain (29% CP if dry).

3) NON-PROTEIN NITROGEN (NPN) Which is primarily either Urea or Biuret. NPN can be easily converted into real protein by the rumen microbes if it is fed in the proper ratios. NPN from plant sources, by the way, is ever present in all plants but in differing ratios. NPN is inversely proportional to Brix (energy levels) in the plant. Spring forage plants are quite often loaded with NPN, to the extent that it becomes excessive at times and can cause loose manure or even worse health problems. When NPN is used to elevate the total supplemental crude protein beyond about 25% problems also ensue, especially when Urea is used. Excess urea, if not used by the microbes explodes into pure ammonia in the rumen, going directly to the blood stream. While some ammonia is converted back into urea by the liver, ammonia poisoning can ensue which is fatal. On the other hand, Biuret does not release rapidly into ammonia and is therefore very safe. While the curve for Urea is to spike instantly into ammonia, the curve for Biuret is almost identical to the release from soybean oil.


Protein supplementation opens up huge areas of protein-starved land across the US to sustainable and profitable livestock production. Typically animals that are supplemented with protein supplements gain weight over the winter in excess of those on non-supplemented feeds and have a higher conception rates. Studies are common that show an ADG increases of 0.25# per head per day, a 10% increase in conception rates and calves that are several pounds heavier as well as far stronger and healthier at birth.


Forage Buster 2 is one of the leading products available anywhere for use as a protein supplement. It is affordable and delicious, cattle love it. This is a time-tested mixture of the safest and most effective sources of NPN know, mixed with natural sources of protein and protein coproducts. It is then mixed with the full array of soluble and chelated minerals and full-strength fatsoluble vitamins. It also contains active forms of Calcium and Phosphorus in a 1:1 ratio. The product is designed specifically for cattle. If you are interested in using it for other species be sure to contact Mike Wichman direct before using. Copper levels with FB2 can be too high for sheep and we donʼt use these protein supplements for animals producing milk for human consumption.

Ingredients include biuret, cottonseed meal, soybean meal, cane molasses and seasalt. When FB2 is used, one may utilize all the minerals it contains and there is no need to supplement with other minerals. A typical daily effective dose is 4 oz per head per day. It can be mixed into a TMR or, if used free-choice, mixed with extra salt which tends to limit daily intake to the correct amount. A typical salt mixture would add 25# of additional salt to 50# of FB2.

Buy Forage Buster Here: Grass Farmer Supply

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