Why heifer mastitis matters

Heifer mastitis can have serious implications for your herd. Contracting mastitis before or after calving, or during the first lactation, can significantly affect udder health and future lactations, ultimately reducing lifetime milk yield.

Because of the impact on both animal welfare and farm profitability, preventing and managing mastitis in heifers should be a priority in any dairy system.

What causes mastitis?

Mastitis is caused by different types of pathogens — disease-causing bacteria that infect the udder. These bacteria establish on the teat and can then enter and grow within the teat canal.

Environmental mastitis pathogens

• Streptococcus uberis (Strep. uberis)
• Escherichia coli (E. coli)
• Klebsiella
• Pseudomonas
• Trueperella

Contagious mastitis pathogens

• Staphylococcus aureus (Staph. aureus)
• Streptococcus agalactiae (Strep. agalactiae)
• Streptococcus dysgalactiae (Strep. dysgalactiae)

Coagulase-negative staphylococci (CNS)

Coagulase-negative staphylococci (CNS) are a bacterial group commonly found in clinical mastitis cases and in quarters with high somatic cell counts, both in cows and in heifers. These infections are considered particularly important in heifer mastitis.

The CNS group includes more than 50 different species and subspecies, although only a smaller number are commonly associated with mastitis. Some appear to behave more like contagious pathogens, while others are more environmental in nature.

CNS infections are often detected immediately after calving.

What type of mastitis are you dealing with?

Heifers are susceptible to mastitis pathogens from the point they begin producing mammary secretions. Infection can therefore be picked up at any stage between birth and first calving.

It is important to track the percentage of heifers with high cell count infections, as well as the rate of new clinical mastitis cases in the first 30 days of lactation.

In affected heifers, individual quarter sampling for bacteriology can help identify the type of infection present and support more informed treatment decisions.

Symptoms of mastitis in heifers

Signs of heifer mastitis can vary, but common symptoms include:

• A swollen teat and/or udder
• A thick, smelly yellow discharge from the teat
• Flies attracted to the discharge
• Swelling of the hind legs
• Lethargy
• Separation from the herd

Reducing and preventing heifer mastitis

Long-term success in controlling heifer mastitis depends on prevention, strong hygiene, and good management practices.

Antibiotic use

Antibiotics for existing mastitis should be viewed as a short-term response. Lasting improvement relies on prevention and better herd management. Dry cow therapy may help treat existing infections before calving, but it should not be relied on as a broad control strategy because infection pressures vary and withdrawal periods can be long. Injectable antibiotics should not be used for mastitis control before calving.

Fly control

Controlling flies can help reduce infection pressure. This may include the use of pour-on or spot-on treatments, fly ear tags, and repellents.

Cross-suckling

Preventing cross-suckling is important to reduce the spread of infection. Feeding milk replacer or pasteurised milk can also help avoid risks linked to antibiotic residues and diseases such as Johne’s.

CNS prevention

To help prevent CNS-related mastitis, heifers should be kept in a clean, dry environment in the period before and during calving. Good teat disinfection, correctly functioning milking equipment, and effective post-milking teat dipping are all important in reducing risk.

How Herdwatch can help

Herdwatch allows you to monitor individual cow performance through the Milk Performance module, making it easier to spot potential health issues on a case-by-case basis from your phone.

Heifer mastitis is often first identified when a heifer shows abnormal milk or an increased somatic cell count (SCC) after calving. Monitoring SCC and related milk performance data can help you spot warning signs earlier.

How to view milk performance by cow

• Tap on Performance
• Tap on Milk Recordings
• Tap on Per Cow

The Per Cow section breaks down milk recording data for each individual animal and can be filtered to help identify cows needing attention.

Filter milk recording data by:

• Date of milk recording
• Lactation
• Calving date
• Days in milk
• SCC
• Milk kg
• Fat
• Protein
• Milk solids
• EBI

Protect future herd performance

Heifer mastitis can affect productivity long beyond the first lactation. By focusing on prevention, monitoring milk performance closely, and responding early, farmers can reduce losses and support healthier, more productive cows.