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Effects of Nitrate and Pathogenic Nanoparticles on Reproductive Losses, Congenital Hypothyroidism and Musculoskeletal Abnormalities in Mares and Other Livestock: New Hypotheses

Spontaneous abortions, congenital hypothyroidism and musculoskeletal abnormalities were attributed to high nitrate in the diet of pregnant mares on Thoroughbred farms in central Kentucky. These fetal losses, with an unknown etiology, and associated with the Mare Reproductive Loss Syndrome (MRLS) have plagued horse farms in central Kentucky for decades. Fetal losses occur in mares grazing spring pastures affected by climatic and environmental factors including droughts, cold-stress, nitrogenous fertilizers, and herbicides. These factors may cause nitrate to accumulate in pasture forages. On a Thoroughbred horse farm, mares affected with the MRLS, pregnant Boer goats grazing high nitrate pastures also were affected with fetal losses. When spring pastures were not fertilized with nitrogen, herbicides not applied, protein reduced in the ration and the diet increased in sodium, fetal losses did not occur and foals were normal at birth. Excessive nitrate, ammonia and sulfate in the diet were associated with the formation of toxic and pathogenic abiotic nanoparticles in the amnionic fluid and pathognomonic placental lesions consistent with the MRLS. Pathogenic nanoparticles were found in aborted fetuses of other livestock. The discovery of these toxic pathogenic abiotic micro and nanoparticles in developing fetuses is unique. This novel mechanism of action for the pathogenesis of fetal losses may be a predisposing factor for a host of opportunistic diseases in livestock. The pathogenic nanoparticles collect in the vessels of the placenta and other organs to form niduses that predispose fetuses to a host of opportunistic microorganisms.

Nitrate Toxicity, Pathogenic Nanoparticles, Fetal Loss, Congenital Hypothyroidism, Musculoskeletal Abnormalities

Thomas Walter Swerczek, Alan Ray Dorton. (2019). Effects of Nitrate and Pathogenic Nanoparticles on Reproductive Losses, Congenital Hypothyroidism and Musculoskeletal Abnormalities in Mares and Other Livestock: New Hypotheses. Animal and Veterinary Sciences, 7(1), 1-11.

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