Abstract
Forty-eight, 9-week old Sprague Dawley female rats (159 ± 13 g) were used to evaluate the effects of feed restriction and/or ginger oil (Zingiber officinale) supplementation on growth, reproductive parameters and blood metabolites. The experiment lasted for 40 days; 10 days of adaptation and intake assessment and 30 days of treatment and data collection. Animals were randomly divided into 4 treatment groups (12 rats/treatment) in a 2 x 2 factorial arrangement; ad libitum feed (CON), 25% feed restriction (G2), ad libitum feeding with 0.2 mL/rat ginger oil (G3), and 25% feed restriction plus 0.2 mL/rat ginger oil (G4). Animals in groups G2 and G4 received 75% of their pre-treatment feed intake (25% restriction). Rats were individually placed in plastic cages in a temperature-controlled room. Ginger oil was supplemented orally (gavage) while the non-ginger groups received water. Body weight (BW) and size were recorded weekly. Six rats from each group were sacrificed at the end of treatments for blood and tissue collection while the remaining rats were mated with mature males. Animals were fed ad libitum from mating onward. Data were analyzed by a two-way analysis of variance using SigmaPlot 11.0. Data for BW and size were analyzed by analysis of variance for repeated measures. No ginger by feed restriction interactions were detected in any of the tested parameters. Body size and BW increased as the experiment advanced (P<0.01), however, G2 had the lowest BW (P<0.05) towards the end of treatment. Cholesterol and triglycerides were unaffected by treatment while glucose and urea nitrogen were influenced by feed restriction (P<0.05); glucose was greater in feed-restricted animals while urea nitrogen was greater in animals on ad libitum feeding. Combined ovarian weights as well as reproductive tract weights were greater (P<0.05) in ginger-supplemented than non-supplemented animals. Similarly, rats on ad libitum feeding had greater ovarian weights (P<0.05) than those on restricted feeding. Birth date, litter size, litter weight, dam birth weight and pup weight were unaffected by treatment. In conclusion, ginger oil supplementation appears to have favorable effects on reproductive tract development and ovarian weights regardless of feed restriction.