Rodents are somewhat more susceptible to high doses than other species, and cholecalciferol has been used in poison bait for the control of these pests. It has been claimed that the compound is less toxic to non-target species. However, in practice it has been found that use of cholecalciferol in rodenticides represents a significant hazard to other animals, such as dogs and cats. "Cholecalciferol produces hypercalcemia, which results in systemic calcification of soft tissue, leading to renal failure, cardiac abnormalities, hypertension, CNS depression, and GI upset. Signs generally develop within 18-36 hr of ingestion and can include depression, anorexia, polyuria, and polydipsia." 
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Certain people are more likely to have vitamin D deficiencies including: breast-fed infants, the elderly, people with dark skin tone, people living in latitudes far from the equator, those not eating a diet fortified with vitamin D, and those who are obese. In certain countries, clothing, for cultural dress or weather conditions can also limit the exposure to sunlight and thus to vitamin D. Even in sunny areas, those people who tend to work or play indoors, or wear sunscreen when outdoors, can have vitamin D levels that are too low.