# Supplementing 25-Hydroxy-Vitamin D3 to Sows Enhances Milk and Blood Parameters, with Extended Benefits to Their Offspring

## TL;DR

Adding 25-hydroxy-vitamin D3 to sow diets improves milk quality and piglet health, offering a new approach to enhance pig production.

## Contribution

This study demonstrates the benefits of 25-hydroxy-vitamin D3 supplementation in sows for improved reproductive and offspring outcomes.

## Key findings

- 25OHD3 supplementation reduced farrowing time and increased the number of piglets born.
- Piglets from supplemented sows had higher daily gain and weaning weight.
- Colostrum and milk from supplemented sows had higher 25OHD3 and protein content.

## Abstract

Vitamin D is essential for maintaining bone strength, reproductive efficiency, and immune function. In sow diets, it supports healthy pregnancies, optimal milk production, and robust piglet growth. However, research on the use of 25-hydroxy-vitamin D3 (25OHD3), a more biologically active and efficient form of vitamin D in sow nutrition, remains limited. Therefore, we conducted this study to examine how adding 25OHD3 to sow diets could enhance their performance and the health status of their offspring. As expected, sow-fed diets containing 25OHD3 improved reproductive performance, enhanced milk quality, and boosted the growth and immune health of piglets. Therefore, we believe that these findings offer a new perspective on the use of 25OHD3 in sow diets and may serve as a practical approach to enhance overall pig production.

The objective of this study was to evaluate the effects of 25-hydroxy-vitamin D3 (25OHD3) supplementation on reproductive performance, nutrient digestibility, lameness score, milk composition, and blood profiles in sows, as well as the performance and blood profiles of their offspring. From day 110 of gestation to 21 days of weaning, a total of 30 multiparous sows (Landrace × Yorkshire) were randomly assigned to one of three dietary treatments, with ten sows per treatment. The dietary treatments were: (1) CON, basal diet; (2) TRT1, CON diet plus 1114 IU 25OHD3/kg (13.92 µg 25OHD3/kg feed); and (3) TRT2, CON diet plus 2227 IU 25OHD3/kg (27.84 µg 25OHD3/kg feed). The reproduction performance and nutrient digestibility of sows were not affected by 25OHD3 supplementation. However, the inclusion of graded levels of 25OHD3 in the sow diet had significantly reduced their farrowing time (p < 0.001) compared to those fed the CON diet. Also, sows fed 25OHD3 produced significantly higher (p < 0.05) number of piglets compared to the CON group. Piglets from supplemented sows exhibited greater (p < 0.05) average daily gain and weaning body weight. Moreover, colostrum protein content was higher (p < 0.05) in sows fed 25OHD3 compared with the CON group. Similarly, the concentration of 25OHD3 in colostrum and milk at weaning was markedly (p < 0.001) elevated. Furthermore, serum 25OHD3 levels were significantly higher (p < 0.05) in both sows and piglets, and piglet serum immunoglobulin G (IgG) concentrations were also elevated (p < 0.05) in the supplemented groups. In summary, dietary 25OHD3 in the sow diet not only improves their reproductive performance and milk quality but also enhances piglet growth, immunity, and overall vitality, suggesting that 25OHD3 is a valuable nutritional strategy for optimizing sow productivity and promoting healthier offspring.