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Updated: Jul 5, 2026
Bovine Mammary Gland Biopsy Techniques
Published on: December 23, 2018
cDNA microarray analysis reveals that antioxidant and immune genes are upregulated during involution of the bovine
K Singh1, S R Davis, J M Dobson
1AgResearch Ltd., Ruakura Research Centre, PB 3123, Hamilton, New Zealand. kuljeet.singh@agresearch.co.nz
Insights
Bovine mammary involution involves early oxidative stress responses and decreased milk protein gene expression. Host defense proteins increase later, preceding immune responses and cell death.
Area of Science:
- Animal Science
- Molecular Biology
- Biochemistry
Background:
- Bovine mammary involution is a complex physiological process.
- Understanding gene expression changes is crucial for managing mammary health.
Purpose of the Study:
- To identify genes involved in bovine mammary involution using cDNA microarray analysis.
- To investigate the temporal expression patterns of key genes during involution.
Main Methods:
- cDNA microarray analysis of bovine mammary alveolar tissue.
- Quantitative real-time reverse-transcription PCR (qRT-PCR) for mRNA expression.
- Western blot analysis for protein expression.
Main Results:
- Upregulation of oxidative stress-associated genes (spermidine/spermine N(1)-acetyltransferase, superoxide dismutase 2, metallothionein 1A, glutathione peroxidase) early in involution.
- Increased expression of host defense proteins (lactoferrin, lingual antimicrobial peptide) later in involution.
- Early decrease in milk protein gene expression (caseins, alpha-lactalbumin) and later decrease in beta-lactoglobulin.
- Downregulation of cell survival factors (beta1-integrin, focal adhesion kinase) during involution.
Conclusions:
- Bovine mammary involution involves early protective responses to oxidative stress.
- Decreased milk protein synthesis and cell survival signaling precede immune responses and apoptosis.
- Gene expression dynamics reveal a coordinated molecular strategy during mammary gland regression.
Abstract:
We have used cDNA microarray analysis to identify genes that play a role in bovine mammary involution. Involution was induced by termination of milking, and alveolar tissue was collected from 48 nonpregnant Friesian cows in mid lactation sacrificed at 0, 6, 12, 18, 24, 36, 72, and 192 h (n = 6/group) postmilking. The most highly upregulated genes were those associated with oxidative stress. Quantitative real-time reverse-transcription PCR analysis confirmed that mRNA expression of spermidine/spermine N(1)-acetyltransferase was increased by 24 h, superoxide dismutase 2 and metallothionein 1A by 36 h, and glutathione peroxidase by 72 h postmilking. The mRNA expression of the host defense proteins lactoferrin and lingual antimicrobial peptide were increased by 192 h postmilking. A dramatic increase in the protein expression of lactoferrin by 192 h postmilking was also detected by Western analysis. Decreased mRNA expression of the milk protein genes alpha(S1)-, beta-, and kappa-casein, and alpha-lactalbumin were early events in the process of involution occurring within 24 to 36 h postmilking, whereas beta-lactoglobulin mRNA was decreased by 192 h postmilking. Decreases in alpha-lactalbumin and beta-lactoglobulin protein levels in alveolar tissue occurred by 24 and 192 h postmilking, respectively, and the cell survival factors beta1-integrin and focal adhesion kinase were decreased by 72 and 192 h postmilking, respectively. The results demonstrate that in the bovine mammary gland, decreased milk protein gene expression and cell survival signaling are associated with multiple protective responses to oxidative stress that occur before the induction of immune responses and mammary epithelial cell apoptosis during involution.
