High concentrations of insulin (411 +/- 214 microU/ml), neurotensin-like (265 +/- 72 pg/ml), and bombesin-like immunoreactivities (1995 +/- 288 pg/ml) were detected in porcine colostrum using radioimmunoassay, as compared to the levels found in sow blood serum at farrowing (5 microU/ml, less than 12 pg/ml, and 17 pg/ml, respectively). After 72 h of lactation, the levels of insulin and neurotensin-like immunoreactivities had decreased to 28 +/- 17 microU/ml and 89 +/- 23 pg/ml, respectively, while the bombesin-like activity remained constant. Characterization with reversed-phase high performance liquid chromatography showed that the insulin immunoreactivity eluted at the same position as the insulin standard, while the elution patterns of the neurotensin-like and bombesin-like immunoreactivities (eluted in three separate peaks) did not correspond to that of their respective standards. The biological function of the peptide hormones in colostrum/milk may be as triggers of the developmental changes taking place in the nursing neonate, especially in the gastrointestinal tract.

Animals↗

PubMedDate not supplied

Assessment of lacrimal IgA as a potential parameter for measurement of long term stress in poultry.

This study, considering the stress of caging on laying hens, looks at the possible use of a product of the immune system; immunoglobulin A (IgA), as a representative measure of the effect of this chronic stress on the immune system of birds. Recording of serum corticosterone served as a traditional measure of stress. The study also considers the possibility of using IgA from the tears as a noninvasive source of samples. Lacrimal IgA is easily accessed by glycerol induction and measured by rocket immunoelectrophoresis. The amount of IgA in tears as well as in serum and possibly the synthesis of IgA seems to be affected by high levels of plasma corticosteroids. Lacrimal IgA levels vary independently of the IgA levels in plasma. It can be concluded that lacrimal IgA may be a useful marker of the effect of stress in poultry. Further studies are needed to facilitate a better understanding of the biological mechanisms that are involved, and to further examine IgA's usefulness as a long-term stress parameter.

Adrenal Glands↗