Dietary supplementation with ovine serum immunoglobulin modulates correlations between mucin, microbiota and immunity proteins in the growing rat.

The objective of this study was to evaluate the relationship among the number of bacteria, number of goblet cells, gut mucin gene expression, mucin protein and immunity protein levels of rats fed a diet containing freeze-dried ovine Ig (FD). Sprague Dawley male rats were used in a 21-days study and were fed a basal control diet (BD; no Ig) and a test diet containing freeze-dried ovine Ig (FD). Diets were isocaloric and contained the same amount of the first limiting amino acids, methionine plus cysteine. Pearson's correlation analysis was conducted on the data (stomach, ileum and colon) obtained from individual rats (n = 10) fed either casein-based diet (BD) or ovine serum Ig (FD) to evaluate the relationship between number of bacteria, number of goblet cells, gut mucin gene expression and gut mucin protein levels. Pearson's correlation analysis was then conducted with the data from the FD fed rats to evaluate the relationship among the above said variables. In the stomach content, a significant (p < .05) correlation was found between the Muc5Ac gene expression and mucosal mucin protein. In the ileum and colon, a significant (p < .05) correlation was observed among the mRNA levels of mucin (Muc2 and Muc4) genes. There was also evidence of a strong relationship (p < .05) between digesta mucin and mucosal mucin protein concentrations. A negative correlation of mucosal IgA protein concentration with total Lactobacillus (in ileum and colon) and total bacteria (in the ileum) was not evident with FD fed rats when compared to the results obtained using both BD and FD fed rats. In conclusion, this study suggests that feeding freeze-dried ovine Ig in growing rats results in a strong correlation between the number of bacteria, mucin and immunity proteins.

Recovery of intact IgG in the gastrointestinal tract of the growing rat following ingestion of an ovine serum immunoglobulin.

The aim of this study was to determine whether orally ingested ovine serum IgG partly resists digestion in the growing rat. Fifteen Sprague-Dawley male rats were allocated to one of three diets for a 3-week study: a control diet (CON) and two test diets containing either freeze-dried ovine serum immunoglobulin (FDOI) or inactivated ovine serum immunoglobulin (IOI). Samples of stomach chyme and intestinal digesta from the ad libitum-fed rats were subjected to ELISA and Western blot analysis. Amounts of intact ovine IgG for the FDOI diet were found to be 13.9, 20.0, 34.1, 13.0 and 36.9 µg in the total wet digesta from the stomach chyme, duodenal, jejunal, ileal and colonic digesta respectively. Qualitative detection by Western blot revealed the presence of intact ovine serum IgG with a ~150 kDa MW. This was detected in all of the gut segments (stomach chyme, duodenal, jejunal, ileal and colonic digesta) for growing rats fed the FDOI diet. No ovine IgG was detected in the chyme or digesta from rats fed the CON or the IOI diets. Ovine serum IgG partly resisted digestion in the growing rat fed the FDOI diet and was found throughout the digestive tract. These results provide a basis to explain the reported biological effects of orally administered immunoglobulin.

Orally administered ovine serum immunoglobulins modulate dental plaque in cats.

The effects of orally administered ovine serum immunoglobulin on dental plaque and associated oral immunity in cats were investigated. The two treatment groups consisted of 1) cats that were fed unsupplemented kibble (control diet) and 2) cats that were fed the same kibble but coated with a freeze-dried ovine serum immunoglobulin preparation (ovine Ig) (test diet). The adult cats were randomly allocated to one of the two diets (n = 15) and received their respective kibble for a 28-day experimental period. When compared to the ovine Ig-supplemented kibble, cats consuming the unsupplemented kibble had significantly (p < 0.05) higher dental plaque scores. Cat IgA and IgG concentrations in the saliva and serum were significantly (p < 0.05) higher for cats fed the unsupplemented kibble when compared to cats receiving the ovine Ig supplement. Similarly, myeloperoxidase activity in the saliva was significantly (p < 0.05) higher for cats fed the unsupplemented kibble when compared to cats receiving the Ig-supplement. Orally administered ovine serum Ig positively influenced oral health and oral immunity in cats as evidenced by preventing an increase of dental plaque formation, salivary and serum IgA and IgG concentrations and salivary myeloperoxidase activity.