Grass-fed Farm Animals Mean More Nutritious, Safer Food

By Marjorie Bender, Program Coordinator for American Livestock Breeds Conservancy
ALBC News Sept - Oct 2002, Volume19, Issue 5

Recent studies have shown that meat, eggs, and dairy products from animals raised on grass are nutritionally superior to animals whose diets are based on grain.

Grass-fed meat production benefits

When ruminants such as cattle, sheep, and goats are grass-fed, their meat contains four times as much vitamin E and eight times as much beta-carotene, both antioxidants thought to inhibit cancer, as compared to when they are grain-fed. Grass-fed meat also has three times as much omega-3, an essential fatty acid, that when equally balanced with omega-6 fatty acid positively affects HDL and LDL cholesterol levels, thereby enhancing cardiac health. Grass-fed products are higher in conjugated linoleic acid (CLA), a natural mutagen inhibitor produced by rumen bacteria from linoleic acid. CLA levels are at their highest when animals are fed a grass diet. High levels of CLA in the human diet are thought to prevent and retard cancer as well.

Chicks hatched from factory eggs contained fatty deposits in the aortas, while chicks hatched from free-range birds had no such deposits. At maturity, none of the chickens raised free-range had fatty deposits, while birds raised in confinement had significant deposits. Better health in the free-range birds was attributed to their more natural diet, including foods rich in essential fatty acids. Pasture produced eggs contained significantly more folic acid and vitamin B12. A USDA Sustainable Agriculture Research study showed the nutritional superiority of eggs from grassfed poultry. As stated in Why Grassfed is Best, "Compared with eggs from caged birds, they had 10 percent less fat, 40 percent more vitamin A, and 400 percent more omega-3 fatty acids… [and]… 34 percent less cholesterol."

Grass-fed milk production benefits

Milk produced from grass-fed animals is also higher in beta-carotene, and vitamins A and E. Grass-fed milk has five times more CLA than milk from confinement dairies, and contains roughly equal amounts of omega-3 and omega-6 fatty acids. Fresh pasture contains more and better-balanced ratios of these nutrients than does grain or hay. Most dairy cows in Europe and New Zealand are managed primarily on pasture. Today, approximately 10 - 15 percent of American dairy farmers have switched to grass-based production.

Other benefits

In addition to these valuable nutrients, a grass-based diet produces less acid in the animals' digestive system. Grain creates an abnormally high acidic environment in the digestive tract of a ruminant. This highly acidic environment causes E. coli to multiply and to become more acid-resistant. Unfortunately, acid-resistant bacteria are likely to survive human digestive juices and cause disease. A study in the March 28th, 2000 issue of the Proceedings of the National Academy of Sciences reported that thirty-three percent of cattle may host the deadliest strain of E. coli bacteria (0157:H7), a ten-fold increase over earlier estimates.

Grass-fed products are linked to a lower risk of cancer, cardiovascular disease, autoimmune disorders, allergies, diabetes, obesity, dementia, and other mental disorders. While products from grass-fed animals present fewer disease risks to consumers than those of grain-fed animals, they are also less likely to carry chemical or antibiotic residues.

Besides providing healthier food, grass feeding is environmentally friendly and can increase the diversity of pasture plants when thoughtfully managed. Researcher Richard H. Hart from Colorado State University studied plant communities for 55 years. His study was conducted on pasture that was protected from grazing and pasture that was grazed lightly, moderately, or heavily. The study found that, "Moderately-grazed pasture showed the greatest biodiversity with more kinds of plants than the lightly or heavily grazed pastures, and was not as completely dominated by the most common species as the ungrazed enclosures, where diversity was least."
Since 1993, the T.O. Cattle Company in San Juan Bautista, California has been carefully controlling herd size and movement to "mimic the natural disturbance of native ungulates on the landscape." The results include 1) an increased number and variety of native plants 2) increased vegetative cover of stream banks 3) expanded wetlands 4) hastened decomposition of manure and 5) an extended growing season of the grassland. Additionally, in a two-year period, the percentage of perennial grasses increased from 40 to 50 percent.

Using rare breeds

Modern agriculture has intensely selected livestock and poultry for uniformity, predictability, and maximum productivity on grain-based diets. Grass-based systems, however, require genomes with characteristics for climate adaptation, efficient utilization of a wide-range of forages, reproductive and maternal ability, parasite and disease resistance, and longevity. Many of the breeds, which are now out of favor, exhibit these characteristics. In addition, their genetic distance from commercial breeds can impart astounding hybrid vigor to any cross. These breeds include:
" Devon, Galloway, Highland and Red Poll beef cattle;
" Ayrshire, Dutch Belted, Milking Devon and Milking Shorthorn dairy cattle;
" Myotonic and Spanish meat goats;
" Barbados Blackbelly, Cotswold, Gulf Coast Native, Katahdin, St. Croix, and Tunis sheep;
" Gloucestershire Old Spots, Hereford, Large Black, and Tamworth pigs.

This growing understanding of the benefits of grass-fed animals to both our food, health, and environment is an argument for choosing rare breeds.

William Baker's family raises Highland cattle in Orford, New Hampshire. Baker acquired the breed because it was hardy and would consume the grasses, brush, and saplings in the fir stands on his farm. Highland cattle are one of a few breeds that perform well on forage, the result of centuries of adaptation to the rugged Scottish Highlands. The breed is well fitted for a cold environment where pastures may be less than optimal. Highlands are genetically pre-potent, passing on vigor, hardiness, and beef quality when crossbred. Baker's cattle are raised exclusively on pasture as breeding stock and for meat. He describes the beef as exceptional in flavor and tenderness, though it contains little marbling. Not only does pasture-based production cost less; the meat is healthier for consumers.

Kenneth and Winifred Hoffman are grass dairy farmers in Earlville, Illinois. They found their Holsteins did not perform well on the permanent pasture system they implemented in the early 1980s, so they began milking Dutch Belted and American Milking Shorthorn cattle instead. Both of these breeds have been selected for forage efficiency.
The Dutch Belted is named for its country of origin and its unusual color pattern: black or red with a white belt around its middle like a belt. The breed is healthy, fertile, and long-lived; traits that reduce the need to replace cows in the milking herd on a frequent basis. Many Dutch Belted cows produce over 20,000 pounds of milk annually on a forage-based diet. The Dutch Belted also produces a quality carcass due to the breed's high ratio of muscle to bone.
The American Milking Shorthorn was selected from British stock for both milk and meat production. In the twentieth century, the breed has experienced significant genetic introgression as efforts were made to enhance its milk production. In the process, many of their most useful traits were lost. A few pure strains remain that retain these valuable traits: longevity, health, hardiness, forage efficiency, and fertility. Additionally, their beef attributes result in quality carcasses.
Poultry and pigs produce a more nutritious and healthier product as well when raised on pasture, although these non-ruminant species cannot be raised on grass alone.

The attributes that enable rare breeds to thrive in grass-based systems are prompting producers to re-examine them. These breeds and attributes, however, must be safeguarded. Extinction of these breeds would seriously reduce the options available to food producers of the future.

Christman, C.J., D.P Sponenberg, D.E. Bixby. (1997) A Rare Breeds Album of American Livestock. American Livestock Breeds Conservancy.

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Diez-Gonzalez, F., et al. (1998). "Grain-feeding and the dissemination of acid-resistant Escherichia coli from Cattle." Science 281, 1666-8.

Jensen, S. K., A. K. Johannsen, et al. (1999). "Quantitative secretion and maximal secretion capacity of retinol, beta-carotene and alpha-tocopherol into cows' milk." J Dairy Roes 66(4): 511-22

Robinson, Jo. (2000). Why Grass-fed is Best! Vashon Island Press or visit

Sinclair, H. (1960). "Essential Fatty Acid Content of Hens' Eggs." The Lancet. January 28, 1961.

Tolan, A., et al, "Studies on the Composition of Food, The chemical composition of eggs produced under battery, deep litter, and free-range conditions." Br. J. Nutrition, (1974) 31:185.