Table IV.

Experimentally Induced Hypovitaminoses of Guinea Pigs^a

Vitamin	Major clinical signs, gross and microscopic lesions	Comments and suggested replacement dosageb
Thiamin (B1)	Anorexia followed by tremors, ataxia, opisthotonus	Unstable in diets containing oxidizing agents: e.g., K2HPo4; 0.6 mg per os or im daily as necessary
Riboflavin (B2)	Poor growth, rough hair coat, pallor of extremities, corneal vascularization	Quantitative requirements not determined; 1 mg per os or im daily as needed
Niacin (nicotinic acid)	Poor growth, pallor of extremities, drooling, anemia	No ocular, anal, or skin lesions noted; niacin is produced from tryptophan; 6 mg per os or im daily as needed
Pyridoxine (B6)	No notable clinical signs; poor growth	0.6-l.0mgper os or im daily as as needed
Folic acid (pteroglutamic acid)	Lethargy, weight loss, anemia, and leukopenia; after 5 weeks profuse salivation with terminal convulsions	1 mg per os or im daily
Pantothenic acid	Anorexia, weight loss, rough hair coat, GI and/or adrenal hemorrhage	2.5 mg per os or im daily as needed
Choline	Poor growth, anemia, myasthenia; occasional fatty liver in adults but not in young	Turnover of choline is slow because of lack of or low levels of hepatic choline oxidase; choline chloride 150 mg daily
Vitamin C	Weakness, anorexia, anemia, defective collagen synthesis, maintenance, and repair, and impaired clotting result in disturbed growth centers in long bones and ribs, and widespread hemorrhages primarily within superficial fascia, gingiva, skeletal muscles, and around joints	25–50 mg daily per os or im
Vitamin A (deficiency)	Poor growth, weight loss, desiccation of edge of pinna, edema, xerophthalmic keratitis; extensive squamous metaplasia of epithelium of trachea, urinary bladder, and uterus	1.5 mg vitamin A acetate daily per os or im
Vitamin A (excess)	Degeneration of epiphyseal cartilage; 200,000 USP units/kg (120mg/kg) in female 14 to 20 days pregnant is teratogenic, producing mainly agnathia, synotia, and microstomia
Vitamin D	Broadened cartilage plates in epiphysis of long bones; enamel hypoplasia of incisors, weight loss; may be unessential if calcium/phosphorus ratio is normal	6 mg (240IU) per os or im daily
Vitamin E	Myasthenia, paralysis; fetal malformation and resorption skeletal muscle degeneration; testicular atrophy and degeneration	15 mg per os or im daily
Vitamin K	Unknown	None

^aSee Table II for requirements.

^bMost suggested dosages are based on providing vitamins in an amount approximately fivefold in excess of that contained in the diet formulated by NIH (Navia and Hunt, 1976) assuming a daily intake of 40 gm/kg for a 750 gm animal.