Changes in peripheral blood mononuclear cells after calving in lactating cows with serious decrease of body weight...

Area of Science:

• Veterinary Immunology
• Dairy Cow Physiology
• Metabolic Disorders in Livestock

Background:

• Periparturient dairy cows often experience physiological stress, impacting their immune status.
• Excessive post-calving weight loss is a concern in dairy herds, potentially affecting cow health and productivity.

Purpose of the Study:

• To investigate hormonal and immunological alterations in periparturient dairy cows exhibiting substantial weight loss after calving.
• To correlate weight loss with specific changes in leukocyte populations, cytokine mRNA expression, and hormone receptor levels.

Main Methods:

• Analysis of leukocyte populations and peripheral blood mononuclear cell (PBMC) mRNA for IFN-gamma, IL-4, growth hormone receptor (GH-R), and insulin receptor (Insulin-R).
• Measurement of growth hormone (GH) and insulin concentrations in serum.
• Comparison between a Weight Loss Group (>10% body weight loss) and a Control Group (≤5% body weight loss) post-calving.

Main Results:

• The Weight Loss Group showed higher serum cholesterol and lower blood urea nitrogen levels.
• Significantly fewer CD4(+)CD45R-T cells were observed in the Weight Loss Group 1-2 months post-calving.
• PBMC mRNA expression of IFN-gamma/IL-4 tended to be lower, and GH-R levels were reduced in the Weight Loss Group during month 2.

Conclusions:

• Excessive post-calving weight loss in dairy cows is associated with compromised cellular immune function.
• Hormonal and immunological changes, including altered immune cell profiles and hormone receptor expression, are implicated in this condition.