Consensus statement immunonutrition and exercise

In this consensus statement on immunonutrition and exercise, a panel of knowledgeable contributors from across the globe provides a consensus of updated science, including the background, the aspects for which a consensus actually exists, the controversies and, when possible, suggested directions for future research

Sun exposure in pigs increases the vitamin D nutritional quality of pork

<div><p>There is a high prevalence of vitamin D insufficiency and deficiency worldwide likely because of both limited sun-exposure and inadequate dietary intake. Meat, including pork, is not typically considered a dietary source of vitamin D, possibly because of management practices that raise pigs in confinement. This experiment determined the vitamin D content of loin and subcutaneous adipose tissue in sun-exposed finisher pigs. Two separate groups of pigs were used. The first group (28 white Landrace-Duroc) was assigned at random to either sunlight exposure (SUN) in spring and summer or confinement per standard practice (Control). The second (24 Yorkshire-Duroc-Landrace) underwent the same exposure protocol but was exposed in summer and fall or assigned to control (Control). A subsample of five SUN and four Control pigs, matched for weight and body condition score, was selected for slaughter from each group. Pigs (n = 10 SUN, n = 8 Control) had blood drawn for analysis of 25(OH)D₃ concentration before/after sun exposure or control, and tissue samples were taken at slaughter for analysis of tissue vitamin D3 and 25(OH)D₃ concentration. Three random samples from a single loin chop and surrounding adipose were collected and analyzed. Serum concentrations of 25(OH)D₃ did not differ (P≥0.376) between treatments prior to sun exposure in either group, but was increased (time*treatment interaction, P<0.001) with SUN exposure. Total vitamin D content (D3 plus 25(OH)D₃) of loin tissue was increased (P < 0.001) with sun exposure and averaged 0.997±0.094 μg/100g and 0.348±0.027 μg/100g for sun and control pigs, respectively. While exposure to sunlight increased (P = 0.003) tissue content of 25(OH) D in subcutaneous adipose tissue, vitamin D₃ content was similar between treatments (P = 0.56). Sunlight exposure in pigs increased the vitamin D content of loin, and may provide an additional source of dietary vitamin D.</p></div

Body weight and body composition in the subgroup of sun-exposed and control pigs selected for tissue analysis.

<p>Body weight and body composition in the subgroup of sun-exposed and control pigs selected for tissue analysis.</p

Nutrient content of soybean and corn feed with added vitamin and mineral premixes.

<p>Nutrient content of soybean and corn feed with added vitamin and mineral premixes.</p

Summer and fall average UVB exposure.

<p>Average UVB radiation during noontime sun exposure for 14 days in the summer and fall at close to the summer solstice and fall equinox, respectively. Data were recorded every second for the one hour exposure period around solar noon (± 30 minutes). Each point represents the mean of the 3600 points. Error, expressed as 95% confidence intervals about the mean are not visible (range = 6.2 X 10⁻⁵ to 0.033731). Days with low UVB radiation were cloudy during the sun exposure period.</p

Effects of sun exposure on vitamin D status.

<p>Serum 25(OH)D₃ concentrations before (Pre) and after (Post) sun exposure for one hour daily at solar noon for 2-weeks (SUN) or standard confinement (Control) in the summer and fall. Summer exposure occurred in the spring-summer group and fall exposure occurred in the summer-fall group in finisher pigs 2-weeks prior to slaughter.</p

Effects of sun exposure on vitamin D concentrations in loin tissue.

<p>Total vitamin D content includes both vitamin D₃ and 25(OH)D₃. The black bar represents the value presented in the USDA national nutrient database for the vitamin D content of “raw pork, center loin.” Center loin samples were collected on the day of slaughter. Error bars represent the standard error. (1 ug vitamin D₃ = 40 IU).</p