Corbee R J, Tryfonidou M A, Grinwis G C M, Schotanus B, Molenaar M R, Voorhout G, Vaandrager A B, Heuven H C M, Hazewinkel H A W
Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
Vet J. 2014 Dec;202(3):503-9. doi: 10.1016/j.tvjl.2014.09.029. Epub 2014 Oct 13.
The first aim of this study was to determine whether vitamin D supplementation influenced the effects of high vitamin A intake on new bone formation in adult cats. The second aim was to determine whether high vitamin A intake in cats caused liver pathology and, if so, whether the current upper limit for the dietary intake of vitamin A for healthy adult cats would be safe. Twenty-four healthy adult cats were divided into four groups that received a control diet supplemented with peanut oil (control), or peanut oil containing a 100-fold increase in vitamin A (HA), or a 100-fold increase in vitamin A and a fivefold increase in vitamin D (HAMD), or a 100-fold increase in vitamin A and a 65-fold increase in vitamin D (HAHD) over a period of 18 months. Cats did not show abnormal locomotion or clinical signs of liver failure after 18 months of supplementation but did show subtle skeletal changes and liver pathology, suggesting that the current National Research Council (2006) safe upper limit for vitamin A for cats is too high. The addition of vitamin D did not seem to influence bone pathology. While moderately elevated dietary vitamin D levels (HAMD) seemed to protect cats against the liver pathology caused by the consumption of large amounts of vitamin A, higher dietary levels of vitamin D (HAHD) did not seem to be protective.
本研究的首要目的是确定补充维生素D是否会影响成年猫高维生素A摄入量对新骨形成的作用。第二个目的是确定猫摄入高剂量维生素A是否会导致肝脏病变，如果会，那么目前健康成年猫维生素A饮食摄入量的上限是否安全。24只健康成年猫被分为四组，在18个月的时间里，分别接受补充花生油的对照饮食（对照组），或含维生素A增加100倍的花生油（高维生素A组），或维生素A增加100倍且维生素D增加5倍的花生油（高维生素A高剂量维生素D组），或维生素A增加100倍且维生素D增加65倍的花生油（高维生素A极高剂量维生素D组）。补充18个月后，猫未表现出异常运动或肝衰竭的临床症状，但确实出现了细微的骨骼变化和肝脏病变，这表明美国国家研究委员会（2006年）目前规定的猫维生素A安全上限过高。添加维生素D似乎并未影响骨骼病变。虽然适度提高饮食中维生素D水平（高维生素A高剂量维生素D组）似乎能保护猫免受大量摄入维生素A所导致的肝脏病变，但更高的饮食维生素D水平（高维生素A极高剂量维生素D组）似乎并无保护作用。
