Science of MagnitudeTM Research Evaluating the Impact of Feeding MagnitudeTM on Stallion Sperm Production and Motility Characteristics

The phospholipid membrane of mammalian spermatozoa has a characteristic fatty acid composition. In most mammals, DHA (docosahexaenoic acid; 22:6, a long-chain polyunsaturated omega-3 fatty acid, or a LC-PUFA) is the major component of the membrane, although this varies by species as well as by individual (4, 8). Recent research suggests that DHA is important to normal spermatozoa function. The deficiency of LC-PUFAs in the spermatozoon plasma membrane, especially DHA, is one marker of impaired fertility in men (4). The semen lipid profiles for boars and stallions are similar (8), and studies have shown that a high DHA to DPA (docosapentaenoic acid; 22:5, an omega-6 fatty acid) ratio is associated with greater fertility (9). In boars, high DPA concentrations are associated with poor semen quality, while high DHA concentrations are associated with good semen quality. Moreover, boars fed DHA-enriched diets had ejaculates with increased sperm concentration and a higher percentage of morphologically normal spermatozoa (10). This relationship may be especially important in stallions. Popular stallions in all breeds are often bred to a large number of mares. But, approximately 30 percent of stallions have semen that has poor quality after cooling and storage at 5 C, or after freezing and thawing. Horses and other animals are unable to synthesize the essential omega-3 LC-PUFAs from saturated or monounsaturated fatty acids, thus, they must be provided in the diet. Unfortunately, most horse feeds are very high in precursors for omega-6 fatty acids while the precursors for omega-3 fatty acids, such as DHA, are low. Plant sources of omega-3 fatty acids, such as flaxseed meal or flaxseed oil, contain only short chain precursors that cannot be converted to DHA in sufficient quantities to meet requirements. Research at Colorado State University has demonstrated that feeding horses a supplement containing DHA resulted in increased plasma levels of DHA, whereas feeding flaxseed meal did not increase plasma levels of DHA (11). Thus, the omega-3 LC-PUFAs, from marine sources, must be provided in the diet to supply DHA for sperm production. MagnitudeTM provides an unique proprietary blend of LC-PUFAs, in particular the important LC-PUFAs DHA and EPA (eicosapentaenoic acid, 20:5 n-3), plus complimentary antioxidants and vitamins. Magnitude’s source of fatty acids is similar to those often used in human foods and nutriceuticals, and several studies have confirmed the safety of DHA in both humans and other mammals (7). Research suggests that DHA oils do not cause toxicity, even at doses 100 times the daily recommended human intake (2).