Forty-eight intact male pigs were used to investigate the influence of source of protein supplement, corn moisture content, and supplemental vitamin E-selenium survived the cidence of mulberry heart disease, hepatosis dietetica and associated lesions. Pigs fed soybean meal-high moisture corn diets survived fewer days than pigs fed the other diets. None of the pigs fed torula yeast-dry corn or soybean meal-high moisture corn without supplemental vitamin E-selenium survived the 13 week trial. Supplemental vitamin E-selenium increased survival of pigs. A higher incidence of hepatosis dietetica, myocardial degeneration, skeletal muscle degeneration, and exudative diathesis was observed in pigs fed torula yeast-dry corn or soybean meal-high moisture corn than pigs fed soybean meal-dry corn. Supplemental vitamin E-selenium resulted in a reduction in the incidence of the above lesions by approximately 50% with the exception of hepatosis dietetica. Tissue selenium concentration did not appear to be related to the incidence of the various lesions.
Two trials were conducted, involving 48 Yorkshire specific pathogen-free pigs, three to four weeks old, to investigate diets which would result in a high incidence of deaths from mulberry heart disease and hepatosis dietetica in pigs. Diets based on ground corn with torula yeast resulted in a high incidence of death. Protein supplements of dried skim milk or soybean meal with corn did not induce a high incidence of death. Diets supplemented with torula yeast had the lowest selenium concentration and highest (alpha-)tocopherol concentration of the diets investigated and resulted in lower liver selenium concentrations. A higher frequency of hepatosis dietetica, mulberry heart disease, skeletal muscle degeneration and exudative diathesis was observed in pigs fed the low level selenium diets containing torula yeast.
Two trials, involving a total of 144 pigs, were conducted to evaluate the effect of corn moisture content and preservation of corn with propionic acid on performance. Treating of corn containing approximately 76% dry matter with 1.5% w/w of propionic acid and storing in bins open to air resulted in no apparent problems in terms of heating or mold growth during storage. Pigs fed high moisture corn gained at a similar rate and had a feed efficiency equal to or better than pigs fed dry corn (90% dry matter). The addition of propionic acid to corn fed to pigs in groups improved rate of gain. A total of 13 pigs in the two trials died due to hemorrhaging the cause of which is unknown, but death did not appear related to dietary treatment.
