TABLE 1.

Characteristics of 3 studies combining dietary provitamin A carotenoids and preformed vitamin A in male Mongolian gerbils

	Study 1	Study 2	Study 3
Characteristic
Number of gerbils	80	40	66
Baseline age of gerbils, wk	4	4.5	4–5
Endline age of gerbils, wk	14.9	12.6	15–16
Vitamin A depletion, d	14	21	14
Treatment time, d	62	36	62
Baseline body weight (mean ± SD), g	27.9 ± 2.5	39.4 ± 2.0	36.7 ± 3.7
Endline body weight (mean ± SD), g	74.3 ± 6.6	63.2 ± 4.2	71.2 ± 3.8
Vitamin A components in feed
Preformed vitamin A	Fortificant in feed1	Oil supplement2	Fortificant in feed1
Provitamin A carotenoids	Orange carrot, orange maize	Dried cassava leaves	Orange carrot
Preformed vitamin A intakes, μg retinol activity equivalents/d3
Control group	0	0	0
VA+ group	1.1–2.3	7.1	2.2–2.4
VA++ group	—	—	5.3
Provitamin A intakes, µg β-carotene equivalents/d4
Control group	0.1	0	0.1–0.2
Orange carrot, orange maize	111–112	—	—
Orange carrot, white maize	72.3–79.4	—	116–127
White carrot, orange maize	33.4–39.5	—	—
Dried cassava leaves	—	6.6–6.7	—

¹Provided as retinyl palmitate [“Dry Vitamin A Palmitate” (250,000 IU VA/g; DSM Nutritional Products Ltd.)].

²Provided as retinyl acetate (Sigma-Aldrich).

³1 μg retinol activity equivalent = 1.15 μg retinyl acetate or 1.83 μg retinyl palmitate.

⁴1 μg β-carotene equivalent = 1 μg β-carotene or 2 μg β-cryptoxanthin or α-carotene.