Primary Production Practices for Safe Dairy Production

Every glass of milk starts long before it reaches a processing plant or your table. It starts on a farm, with an animal, a milker, a water trough, and a shed. These are the building blocks of primary production – the first and arguably most critical stage in the dairy food safety chain. According to the Codex Alimentarius Code of Hygienic Practice for Milk, microbiological hazards in dairy can be introduced both from the farm environment and from the milking animals themselves, which is why minimizing contamination at this stage is essential. What happens at the farm level directly determines how safe and suitable the final product will be – and no amount of downstream processing can fully compensate for poor primary production practices.

Why primary production is the foundation of dairy safety 🔗

Primary production in dairy refers to all on-farm activities involved in obtaining raw milk – from managing the health of milch animals to handling and storing milk before it leaves the farm. Research published in ScienceDirect highlights that owing to milk’s highly nutritious nature, it serves as an excellent growth medium for a wide range of microbes, making contamination control at every step of primary production non-negotiable. Pathogens such as Salmonella, Listeria monocytogenes, Campylobacter, and Staphylococcus aureus are among the most commonly implicated organisms in dairy-borne disease outbreaks. Controlling them starts at the source – the farm.

The FAO’s Guide to Good Dairy Farming Practices frames food safety at the primary production level around four interconnected areas: animal health and welfare, nutrition and water, milking hygiene, and farm environment management. Each of these areas, when neglected, creates a pathway for contamination into raw milk.

Animal health: the starting point for safe milk 🔗

Safe raw milk begins with healthy animals. The European Dairy Association notes that safe raw milk of high quality comes from healthy cows, making animal health a top priority at the farm level. Diseases like mastitis, brucellosis, and tuberculosis not only reduce milk quality but can introduce harmful pathogens directly into milk. Maintaining healthy milking animals has been shown to reduce the likelihood that human pathogens will be transmitted through milk.

Routine veterinary care and disease management 🔗

The National Milk Producers Federation emphasizes that dairy farmers and their employees must work closely with veterinarians, nutritionists, and specialists such as hoof trimmers to keep animals healthy. Diseases such as Johne’s disease, bovine viral diarrhea, and mastitis can significantly increase costs through decreased milk production and loss of animals. A structured health management program – including vaccination schedules, regular clinical examinations, and documented treatment logs – is central to good primary production practice.

The MSD Veterinary Manual recommends that all treatments administered to dairy cows be recorded in treatment logs to ensure adherence to proper milk withholding periods. This is critical because the improper use of veterinary drugs can result in potentially harmful antibiotic residues in milk. Monitoring somatic cell counts (SCC) – an indicator of udder health – is another standard part of herd health management. A declining SCC signals improved udder health and milk quality.

Biosecurity and disease prevention 🔗

Preventing disease introduction onto a farm is just as important as treating illness. MSU Extension’s dairy biosecurity guidance recommends isolating new animals for a minimum of two weeks before commingling them with the existing herd, and monitoring the health of incoming animals before integration. All visitors and service providers – including hoof trimmers, nutritionists, and veterinarians – should follow biosecurity protocols such as using clean footwear, changing clothing, and disinfecting tools before entering the farm. Maintaining accurate records for animal health events, including vaccination, antimicrobial treatments, and surgical procedures, supports traceability and disease response.

Nutrition and water supply 🔗

What a dairy animal eats and drinks directly affects the quality and safety of its milk. The International Dairy Federation (IDF) states that adequate and sustainable feed and water is essential for a dairy animal’s health and productivity, as well as the quality and safety of its milk. Feed must be appropriate for the animal’s physiological state, milk production level, body condition, and health status.

The Codex Alimentarius Code specifically notes that contaminated water used in primary production can introduce hazards into milk. Water used for drinking, washing teats, cleaning equipment, and milking must be of suitable quality and not contribute to the introduction of hazards. Feed storage must also be managed carefully – mold-contaminated or chemically treated feeds can introduce mycotoxins and chemical residues into milk through the animal’s metabolism. Farms should source feed from verified suppliers, store it in dry, pest-free conditions, and avoid overfeeding supplements without nutritional guidance.

Housing and farm environment 🔗

The environment where animals are housed and milked is a major source of contamination risk. Poorly maintained housing allows manure, mud, and environmental pathogens to accumulate on udders and teats, increasing the microbial load in milk during milking. The FAO and IDF’s Guide to Good Dairy Farming Practices recommends that housing areas be designed to provide good drainage and ventilation, avoid animal injury, and maintain adequate loose bedding kept in a hygienic condition. All stalls and beds should be kept clean and dry, with passageways regularly scraped to remove manure.

Ventilation is equally important – inadequate airflow leads to moisture buildup, ammonia accumulation, and mold growth, all of which stress animals and create pathogen-friendly conditions. The milking area itself should be designed to allow thorough cleaning and should be kept tidy at all times. A clean, low-stress environment not only supports food safety but directly supports milk yield and animal welfare.

Waste management 🔗

Effective waste management on a dairy farm prevents environmental contamination and protects both water sources and the farm itself. The FAO/IDF environment guide advises that waste storage areas – including manure heaps and slurry stores – should be sited carefully to avoid pollution of watercourses, underground water, and environmentally sensitive areas. Buffer zones should be maintained near water sources, and slurry stores must be regularly inspected for leaks to prevent runoff. Potential breeding sites for flies and other disease-carrying vermin should be eliminated promptly.

This matters for food safety because contaminated water sources or fly-infested environments can re-introduce pathogens to animals, feed, milking equipment, and milk handlers. A simple written waste management plan that defines when, where, and at what rate to spread manures and slurries is an important part of responsible primary production practice.

Milking hygiene and equipment 🔗

The FAO’s guidance on clean milk production identifies four essential requirements during milking: maintain udders free from infection; manage animals so their udders and teats are clean; milk in a way that minimises bacterial contamination; and store milk in clean containers at temperatures that discourage bacterial growth. Together, these practices can reduce the bacterial count in raw milk to safe levels even before any processing takes place.

Pre- and post-milking teat care 🔗

Pre-milking teat preparation – which includes washing, drying, and disinfecting each teat before attachment – removes environmental contaminants and reduces the risk of mastitis. Post-milking teat dipping is equally important. Cornell University’s College of Veterinary Medicine explains that after milking, the teat sphincter remains open for up to two hours, leaving the animal vulnerable to new infections. Post-milking teat disinfection, as highlighted by the FAO, kills pathogens that may have contacted the teat skin during the milking process.

Cleaning milking equipment 🔗

Milking equipment is in direct contact with both the animal and the milk, making its cleanliness critical to food safety. Dairysafe Australia notes that one of the largest dairy food poisoning outbreaks in history – affecting 224,000 people in the USA – was traced to a milk tanker that had not been properly cleaned between loads. Milking machines should be cleaned after each milking using an appropriate acid or alkaline detergent, followed by disinfection. Food contact surfaces must be smooth, non-corrosive, non-toxic, and free from cracks or crevices that can harbor bacteria. Equipment should be stored dry between uses, as bacteria multiply rapidly in residual moisture.

Personal hygiene of milk handlers 🔗

The person doing the milking is often the most overlooked link in the dairy safety chain. The FAO/IDF Guide is clear on expectations for milkers: wear suitable and clean working clothes; keep hands and arms clean especially when milking; cover cuts or wounds; and not have any infectious disease transmissible via milk. Hands are a direct vector for pathogen transfer between animals, equipment, and milk.

Cornell’s dairy hygiene guidance specifies that hand and boot disinfection should be applied before and during milking, and also when moving from one group of animals to another – for instance, from lactating cows to calves. Boot baths must be regularly cleaned and refreshed, as disinfectants lose efficacy when contaminated with organic material. Cornell CALS emphasizes that food handlers and supervisors should receive appropriate training in proper food handling techniques and food-protection principles, and should be informed of the danger of poor personal hygiene and insanitary practices.

Milk handling, storage, and temperature control 🔗

Once milk leaves the udder, temperature becomes the primary tool against microbial growth. Research published by Allied Academies notes that from the milking process to storage and transportation, a consistent cold chain must be maintained to prevent the growth of harmful microorganisms. Milk should be cooled rapidly after milking and held at temperatures that inhibit bacterial multiplication until it reaches the dairy plant. Monitoring equipment should be calibrated regularly, and staff trained on temperature control protocols. The principle of “first arrived, first processed” should also apply at the dairy plant level to prevent aging of raw milk in storage tanks.

What do you think? Given that primary production practices vary widely between large commercial dairy farms and smallholder operations in developing countries, how can food safety standards be made practical and achievable at every scale? And considering that a single gap – such as contaminated water or an untreated animal illness – can compromise an entire batch of raw milk, which area of primary production do you think deserves the most urgent attention on dairy farms today?

References

1. https://www.fao.org/fileadmin/user_upload/livestockgov/documents/CXP_057e.pdf
2. https://www.sciencedirect.com/science/article/abs/pii/B9780128007235000103
3. https://www.fao.org/dairy-production-products/production/farm-practices/en
4. https://eda.euromilk.org/wp-content/uploads/2024/05/EDA_Fact_sheet_on_Food_Safety_-_February_2020.pdf
5. https://www.nmpf.org/issues/animal-health/animal-health-welfare/
6. https://www.msdvetmanual.com/management-and-nutrition/health-management-interaction-dairy-cattle/the-health-management-program-in-dairy-cattle
7. https://www.canr.msu.edu/resources/biosecurity-for-dairy-and-beef-cattle-farms
8. https://fil-idf.org/our-work/farm-management/milking-hygiene/
9. https://www.thedairysite.com/articles/guide-to-good-dairy-farming-practice-milking-hygiene
10. https://www.thecattlesite.com/articles/guide-to-good-dairy-farming-practice-environment
11. https://www.fao.org/4/t0218e/T0218E03.htm
12. https://www.vet.cornell.edu/animal-health-diagnostic-center/programs/nyschap/modules-documents/cleaning-and-disinfection-dairy-farm
13. https://dairy-safe.com.au/five-critical-ps-of-gmp/
14. https://cals.cornell.edu/dairy-extension/what-we-do/food-safety-resources/good-manufacturing-practices
15. https://www.alliedacademies.org/articles/adoptable-food-safety-measures-for-dairy-production-28376.html