Cotton: It’s not just for T-shirts and bed sheets

According to the National Cotton Council, 12 million acres of cotton are grown in 17 states across the southern half of the U.S., from Virginia to California. Our nation’s cotton farmers harvest 15 million bales or 7.3 billion pounds of cotton each year.

Simon Kern

The often overlooked component of the crop is the vast amount of cottonseed produced alongside the fiber. While primarily only used in cotton-producing regions, cottonseed is a nutritious and highly valuable byproduct feed for cattle with a wide variety of uses depending upon the byproduct form and stage of cattle production.

Whole cottonseeds

Whole cottonseeds are heavily utilized by the dairy industry and are the one cotton byproduct feed commonly used outside of cotton-producing regions. Whole cottonseeds are high in protein, fat and fiber, making them an excellent complementary supplement to low-quality forages for beef cows.

Typical supplementation for both beef and dairy cattle is from 3 to 7 pounds of whole cottonseed per head daily. The limiting factor for whole cottonseed use is the high unsaturated fat content which will suppress rumen function if fed at higher levels.

Cottonseed meal

Cottonseed meal is a high-protein feedstuff very comparable to soybean meal. Cottonseed meal should be valued at 85 to 90 percent of the nutritional value of soybean meal and can be used as a partial substitute for soybean meal in most cases.

Cottonseed meal is typically priced at a 25 to 35 percent discount to soybean meal, making it a cost-effective replacement barring freight cost.

One concern with cottonseed meal is an inconsistent nutrient profile. This is largely dependent upon the degree of dehulling and the efficiency of oil extraction which can result in wide-ranging nutrient values (protein 30 to 50 percent, fat 3 to 12 percent, crude fiber 5 to 25 percent).

Due to its high protein digestibility, cottonseed meal is also a great complement to low-quality forages. Cottonseed meal can be fed at up to 15 percent of the total dietary dry matter in cattle with fully functioning rumens (greater than 4 to 5 months old) but should be limited to no more than 10 percent of the diet for pre-ruminating calves.

Typical supplementation for mature cows is 2 to 3 pounds per head daily to meet protein requirements.

Cottonseed hulls

Cottonseed hulls consist of the outer covering of the cottonseed and are highly fibrous and low in energy and protein. Cottonseed hulls are more palatable than other fibrous hull byproducts (peanut, sunflower) and can replace the traditional roughage portion of feedlot rations.

Cottonseed hulls can also be used to partially replace forage in cow rations; however, it is not commonly cost-effective to replace hay or other forages entirely. The effective geographic use range for cottonseed hulls is less than that of whole seed or meal simply due to its low bulk density and added freight cost.

Cotton gin trash

Each 480-pound bale of cotton produces between 150 and 200 pounds of gin trash. Cotton gin trash is typically offered free of charge but must be freighted by the user. Just as with cottonseed hulls, the low bulk density of gin trash severely limits its effective use range due to transportation cost.

In addition, gin trash has a highly variable nutrient profile and is extremely susceptible to mold growth due to the water added by many gins to reduce dustiness.

Palatability of gin trash is also suspect, and it may take cattle a few days to become accustomed to it. Gin trash will typically provide adequate protein to beef cows, but additional energy will likely need to be supplemented. It is best to feed gin trash to mid-gestation, non-lactating mature beef cows due to their low energy requirements.

Additionally, gin trash may be used in feedlot diets to replace traditional forage in a similar fashion as cottonseed hulls.

Limitations and concerns

As with most byproduct feeds, there are use limitations and other items of concern. The primary concern with cottonseed byproducts is a compound inherent to the cotton plant called gossypol. Gossypol is a naturally occurring pigment primarily found within the inner portion of the cottonseed.

While gossypol is benign in the bound form, the free form has the potential to cause complications as severe as heart failure or liver necrosis when fed at high levels for an extended period of time. While gossypol content of whole cottonseeds and cottonseed meal are a concern, cottonseed hulls and gin trash are not likely to contain a limiting level of gossypol due to its concentration within the cottonseed (10 times lower).

Monogastrics and pre-ruminating calves are highly susceptible to gossypol poisoning, while mature ruminants are much more tolerant due to the detoxification process initiated by microbes in the rumen.

While mature ruminants are not likely to ingest a toxic dose of gossypol, the portion of gossypol which does survive the rumen in the free form can build up in the body and reduce reproductive performance. Females seem to be more resistant to these effects, while bulls are more susceptible and likely to have suboptimal fertility.

The other major concern with feeding cottonseed byproduct is mycotoxicosis and more specifically aflatoxicosis. This is caused by the ingestion of the compound produced by certain strains of Aspergillus mold called aflatoxin.

Dietary levels of aflatoxin generally tolerated by cattle are less than 300 parts per billion; however, levels as low as 10 to 20 parts per billion result in measurable metabolites excreted in milk. The subclinical ingestion of aflatoxin is likely to cause unthriftiness, weakness and reduced growth, while acute outbreaks can result in death.

Ensuring proper handling and dry storage will help to reduce the risk of mold growth and aflatoxin production. Cottonseed meal is not likely to be contaminated with aflatoxin, but all other cotton byproduct feeds should be considered high-risk. Commercial testing for mold and mycotoxins can be conducted if product quality is questionable.

Cotton byproducts offer a variety of feed ingredients which can lower the cost of production for cow-calf producers, stockers and feedlot operators.

While their use is generally limited from a geographical standpoint, producers in cotton-producing regions should find these feedstuffs to be a great fit for their operation when fed in moderation and managed properly.