New developments in animal health

Managing mastitis and maintaining high milk quality can be challenging for dairy farmers, but a new tool called GenoCells could help with that task.

GenoCells is a milk-testing service that determines individual cow somatic cell counts (SCCs) without the need for individual sampling. Instead, the service analyses a bulk milk sample from the herd and uses genomic data to pinpoint which cows are contributing the most to the SCC. This saves time and effort, while ensuring accuracy. This service is available to dairy farms that milk-record and have their herds genotyped, with both Progressive Genetics and Munster Bovine offering the service from next year.

How does GenoCells work?

How often to test?

Testing frequency depends on the farm’s needs, but regular testing every two to four weeks is recommended. This allows farmers to track changes in SCC levels and respond quickly to potential issues. However, the costs of the tests have not yet been disclosed, so how often to test will ultimately depend on the costs involved.

Genotyping the entire milking herd is essential for GenoCells to work effectively. This genomic data forms the basis for identifying individual SCC contributors in bulk milk.

What are the benefits?

What are the downsides?

The cost is not yet known and herds still have to milk-record. When the national genotyping programme was first introduced there was a perception that the technology could replace milk recording for SCC identification, but that doesn’t seem to be the case. Individual cow SCC will not be known, just individual cow’s contribution to the bulk tank SCC will be known.

Crypto vaccine (Bovilis Cryptium)

Cryptosporidiosis, often referred to as “crypto,” has long been a major challenge for farmers, especially during the busy calving season. This infectious scour, caused by the parasite Cryptosporidium parvum, is one of the most common and costly causes of scour in young calves.

However, a breakthrough is on the horizon; MSD Animal Health has received approval to launch Bovilis Cryptium, the first vaccine to combat cryptosporidiosis in cattle, just in time for the 2025 calving season.

Crypto

Crypto affects calves mainly between seven and 14 days old, but can strike at any time. The parasite damages the intestinal lining, impairing nutrient absorption, leading to scour, dehydration and stunted growth. In severe cases, calves can become weak and lethargic, and untreated infections may lead to death. Even treated cases often result in death, such is the severity of the disease.

The disease also has long-term implications. Studies indicate that affected calves gain less weight, reducing their market value. In addition, outbreaks cost farmers both financially and in labour, as managing sick calves involves intensive care, cleaning and disinfecting facilities.

How does it work?

Bovilis Cryptium works by boosting antibodies against crypto in the colostrum of vaccinated cows. When calves consume this colostrum shortly after birth, they receive passive immunity against crypto.

Farmers will administer the vaccine in two doses to in-calf cows, four to five weeks apart, in the last 12 weeks of pregnancy. A single booster dose will be required in subsequent pregnancies, so it is only cows vaccinated for the first time and heifers that need two shots.

To ensure effectiveness, calves must consume sufficient quantities of high-quality colostrum (at least three litres within six hours of birth) and transition milk for five days.

Benefits

The vaccine marks a major step forward but does not eliminate the need for good management practices. Farmers should continue to prioritise hygiene in calf sheds, including thorough cleaning and disinfection to reduce risks of infections carrying over from one season to the next.

While the vaccine is not a silver bullet, it offers an additional layer of protection, particularly valuable for farms where crypto outbreaks are frequent. When combined with other vaccines, such as rotavirus vaccine, farms with a history of crypto and rotavirus scour, will have significantly increased defence against the calf scours, provided calves get enough colostrum.

Cost

According to MSD Animal Health, the crypto vaccine will cost the same as the rotavirus scour vaccine. This costs approximately €8.50/shot, so if giving two shots the vaccine would cost €17/cow this year, with an annual booster cost of €8.50/cow – presuming the costs don’t change.

Understanding selective dry cow Therapy (SDCT)

The dry period is a crucial phase in dairy farming, providing an opportunity to manage mastitis, a common udder infection in cows. Many farms use blanket antibiotic treatment for all cows at dry-off. However, with growing concerns about antimicrobial resistance (AMR), the focus is shifting towards selective dry cow therapy (SDCT).

What is SDCT?

SDCT involves using antibiotics only for cows with a known infection, while others receive a non-antibiotic teat sealant to protect against new infections. This approach reduces antibiotic use.

How do farmers implement SDCT?

Effective implementation of SDCT requires careful preparation:

As a general rule, farmers and vets tend to use sealer only on cows with SCC of less than between 50,000 and 100,000. Different vets have different criteria, but the lower the cut off point, the fewer the number of cows getting sealer only. A lot depends on the farm history of mastitis and risk factors. Even if the average SCC for the year is below the threshold, cows that were treated for mastitis or had a milk recording where SCC was above the threshold should be given antibiotics as well as teat sealer at drying off.

In brief