# Effects of dietary vitamin D3 supplementation on growth performance, blood vitamin D status, and antioxidant capacity in weaning pigs

## TL;DR

This study found that high vitamin D3 supplementation in weaning pigs improved their vitamin D and antioxidant levels, though it did not boost growth performance.

## Contribution

The study demonstrates that higher-than-recommended vitamin D3 levels improve antioxidant status in weaning pigs.

## Key findings

- High vitamin D3 supplementation increased plasma 25-OHD3 levels in weaning pigs.
- High vitamin D3 tended to reduce malondialdehyde and increase superoxide dismutase activity.
- Plasma 25-OHD3 was positively correlated with antioxidant activity at 14 days postweaning.

## Abstract

This study evaluated the effects of dietary vitamin D3 (VD3) supplementation on growth performance, blood vitamin D, and antioxidant status in weaning pigs.

Forty newly weaned piglets (6.02±1.17 kg) were assigned to two treatments with five replicates over a 28-d period. Treatments were 1) NRC-VD3: NRC recommended levels (220 IU/kg in Phase 1 [d 0–14 postweaning] and 200 IU/kg in Phase 2 [d 14–28 postweaning]), and 2) High-VD3: a high level of VD3 (2,000 IU/kg in Phase 1 and 2). Body weight, average daily gain, average daily feed intake, and gain-to-feed ratio were measured weekly. Blood samples were collected at d 14 and 28 postweaning for the analyses of plasma 25-hydroxycholecalciferol (25-OHD3), total antioxidant capacity (T-AOC), superoxide dismutase (SOD) activity, and malondialdehyde (MDA) levels. Pearson correlation coefficients between plasma 25-OHD3 and SOD, MDA, or T-AOC were determined.

Growth performance did not differ in overall nursery period although feed intake was lower in the High-VD3 group than the NRC-VD3 group in d 14–28 postweaning (p<0.05). Pigs fed High-VD3 diets showed greater plasma 25-OHD3 at d 14 and 28 postweaning (p<0.05), tended to have reduced plasma MDA (p = 0.06), and increased plasma SOD activity (p = 0.10) at d 14 postweaning compared with those fed NRC-VD3 diets with no effect in plasma T-AOC. At d 14 postweaning, plasma 25-OHD3 was positively correlated with plasma SOD activity (r = 0.532; p<0.05) and tended to be negatively correlated with plasma MDA levels (r = −0.491; p = 0.06).

High VD3 supplementation at 2,000 IU/kg did not enhance growth performance, while improving plasma vitamin D and antioxidant status in weaning pigs compared to NRC-level supplementation. Therefore, supplementing weaning pigs with higher-than-recommended levels of VD3 could be beneficial to enhance their antioxidant status and overall health.