title: Evaluating the clinical and physiological effects of long term ultraviolet B radiation on guinea pigs (Cavia porcellus).
abstract: Vitamin D is an important hormone in vertebrates. Most animals acquire this hormone through their diet, secondary to exposure to ultraviolet B (UVB) radiation, or a combination thereof. The objectives for this research were to evaluate the clinical and physiologic effects of artificial UVB light supplementation on guinea pigs (Cavia porcellus) and to evaluate the long-term safety of artificial UVB light supplementation over the course of six months. Twelve juvenile acromelanic Hartley guinea pigs were randomly assigned to one of two treatment groups: Group A was exposed to 12 hours of artificial UVB radiation daily and Group B received only ambient fluorescent light for 12 hours daily. Animals in both groups were offered the same diet and housed under the same conditions. Blood samples were collected every three weeks to measure blood chemistry values, parathyroid hormone, ionized calcium, and serum 25-hydroxyvitamin D3 (25-OHD3) levels. Serial ophthalmologic examinations, computed tomography scans, and dual energy x-ray absorptiometry scans were performed during the course of the study. At the end of the study the animals were euthanized and necropsied. Mean ± SD serum 25-OHD3 concentrations differed significantly in the guinea pigs (p<0.0001) between the UVB supplementation group (101.49±21.81 nmol/L) and the control group (36.33±24.42 nmol/L). An increased corneal thickness in both eyes was also found in the UVB supplementation compared to the control group (right eye [OD]: p<0.0001; left eye [OS]: p<0.0001). There were no apparent negative clinical or pathologic side effects noted between the groups. This study found that exposing guinea pigs to UVB radiation long term significantly increased their circulating serum 25-OHD3 levels, and that this increase was sustainable over time. Providing guinea pigs exposure to UVB may be an important husbandry consideration that is not currently recommended.
authors.affiliation: Department of Veterinary Clinical Medicine, University of Illinois, Urbana, Illinois, United States of America.
authors.forename: Megan K
authors.initials: MK
authors.lastname: Watson
authors.affiliation: Department of Pathobiology, University of Illinois, Urbana, Illinois, United States of America.
authors.forename: Adam W
authors.initials: AW
authors.lastname: Stern
authors.affiliation: Department of Veterinary Clinical Medicine, University of Illinois, Urbana, Illinois, United States of America.
authors.forename: Amber L
authors.initials: AL
authors.lastname: Labelle
authors.affiliation: Department of Veterinary Clinical Medicine, University of Illinois, Urbana, Illinois, United States of America.
authors.forename: Stephen
authors.initials: S
authors.lastname: Joslyn
authors.affiliation: Department of Veterinary Clinical Medicine, University of Illinois, Urbana, Illinois, United States of America.
authors.forename: Timothy M
authors.initials: TM
authors.lastname: Fan
authors.affiliation: Department of Veterinary Clinical Medicine, University of Illinois, Urbana, Illinois, United States of America.
authors.forename: Katie
authors.initials: K
authors.lastname: Leister
authors.affiliation: School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Lincoln, Nebraska, United States of America; Oxbow Animal Health, Murdock, Nebraska, United States of America.
authors.forename: Micah
authors.initials: M
authors.lastname: Kohles
authors.affiliation: PetSmart, Phoenix, Arizona, United States of America.
authors.forename: Kemba
authors.initials: K
authors.lastname: Marshall
authors.affiliation: Department of Veterinary Clinical Medicine, University of Illinois, Urbana, Illinois, United States of America.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Mitchell
mesh_terms: D000818:Animals; D002113:Calcification, Physiologic / Q000528:radiation effects; D002118:Calcium / Q000097:blood; D005128:Eye Diseases / Q000209:etiology; D005260:Female; D006168:Guinea Pigs; D010281:Parathyroid Hormone / Q000097:blood; D012449:Safety; D013997:Time Factors; D014466:Ultraviolet Rays / Q000009:adverse effects*; D014807:Vitamin D / Q000031:analogs & derivatives / Q000097:blood
chemical_list: D010281:Parathyroid Hormone; D014807:Vitamin D; C104450:25-hydroxyvitamin D; D002118:Calcium