Integrated Blood Transcriptome and Multi-Tissue Trace Mineral Analyses of Healthy Stocker Cattle Fed Complexed or...

Area of Science:

• Animal Science
• Nutritional Biochemistry
• Immunology

Background:

• Trace mineral supplementation is standard practice for managing bovine respiratory disease (BRD) in post-weaned cattle.
• The specific effects of different trace mineral sources on host immunity and metabolism in high-risk cattle remain incompletely understood.

Purpose of the Study:

• To evaluate the impact of inorganic (INR) versus amino acid-complexed (AAC) trace mineral supplementation on liver and serum mineral concentrations and blood gene expression in high-risk beef steers.
• To compare a combined supplementation approach (COMBO) with AAC alone.

Main Methods:

• Fifty-six high-risk beef steers were assigned to INR, AAC, or COMBO supplementation for 60 days.
• Serum and liver mineral concentrations (Cu, Co, Mn, Zn) were analyzed at multiple time points.
• Whole blood gene expression was analyzed using RNA sequencing, with differentially expressed genes (DEGs) identified.

Main Results:

• Serum and liver copper (Cu) and cobalt (Co) concentrations increased over time in all groups, with higher liver Cu in the COMBO group at day 60.
• Serum and liver Cu and Co concentrations were positively correlated.
• Compared to INR, AAC supplementation resulted in 107 DEGs, with increased carbohydrate/vitamin metabolism, antigen presentation, and immune cell activation, and decreased osteoclast differentiation and neutrophil degranulation.

Conclusions:

• Amino acid-complexed trace mineral supplementation, compared to inorganic sources, significantly influences gene expression related to immune function and metabolism in high-risk cattle.
• Organically sourced trace minerals may offer benefits for adaptive immunity and metabolic processes in cattle susceptible to BRD.