Student conceptions of the production of cow's milk—An exploratory interview study with 6th- and 10th-grade students

**Background:** Food production and livestock farming contribute significantly to climate change and biodiversity loss, hindering achievement of the UN Sustainable Development Goals (SDGs). Germany is the EU's largest cow's milk producer, with approximately four million dairy cows and 33.1 million tons produced in 2019. Education for Sustainable Development (ESD) aims to develop sustainability competence, including understanding food production and consumption (SDG 12). To design effective ESD teaching, it is essential to identify students' existing conceptions. Prior research (Hamann, 2017; Folsche & Fiebelkorn, 2018) examined elementary students' conceptions of agriculture and dairy cow keeping, but no study had specifically investigated conceptions of milk production. This study addressed three research questions: (1) What conceptions do students have of keeping dairy cows? (2) What conceptions do students have of the milking process and technology? (3) What conceptions do students have of milk production in dairy cows?

**Methods:** A convenience sample of eight students was recruited from one grammar school in Osnabrück, Lower Saxony: four sixth graders (n=4; mean age=12 years; SD=0.7 years; 50% female) and four tenth graders (n=4; mean age=16 years; SD=0 years; 50% female). None lived on a farm. Semi-structured interviews were conducted in June 2018 using a multi-method approach combining verbal questioning and drawing tasks (students completed a schematic of a cow and udder). Interviews lasted 15–25 minutes for sixth graders (mean=18.4 min; SD=3.1 min) and 29–48 minutes for tenth graders (mean=38 min; SD=8.5 min). A brief post-interview questionnaire collected sociodemographic data and information about primary/secondary experiences with dairy farms. Audio recordings were transcribed and analyzed using qualitative content analysis in MAXQDA, with a deductive category system based on the three research domains and inductively added categories.

**Key Results:** - **Dairy farming:** Most students realistically estimated stock sizes (20–30 to over 500 animals), though one sixth grader (Mark) assumed 1,000–1,200 animals. Bavaria was the most commonly named location for dairy farms; only one tenth grader (Eva) mentioned Lower Saxony despite students living there. Most students described cubicle housing with free movement and a passage to pasture, reflecting common practice (83% of German dairy cows are in cubicle housing). Two tenth graders (Kristina, Eva) described tethered housing with confined conditions. All students imagined a calving pen, but sixth graders and one tenth grader (Michael) held romanticized views that cow and calf stay together after birth, while three tenth graders correctly described early separation. Stable floor conceptions varied: some described slatted floors with rubber mats (realistic), others mentioned earth, stone, or straw (less realistic). - **Milking process/technique:** All students described mechanical milking with partially automated systems; only Eva (10th grade) mentioned automatic milking robots. Hand milking was considered outdated. Most students estimated milking frequency at 1–3 times per day (realistic) and milking duration at 5–10 minutes per cow (realistic). One tenth grader (Michael) held an unrealistic conception that a cow without a calf is milked once a month. - **Milk production:** Four students (Anna, Mark, Marie, Eva) immediately linked milk production to calving; three needed a hint; Michael believed cows produce milk "passively" before first calving. All except Mark assumed natural insemination by a bull, though three tenth graders also considered artificial insemination. Regarding anatomical location of milk production, only Mark (6th grade) correctly described the udder's mammary gland tissue and cisterns. Most students believed milk production occurs in the stomach, intestines, or a separate organ, with the udder serving only as storage. Only Mark described the udder as permanently made of tissue with some milk remaining after milking. - **Grade comparison:** No significant differences were found between sixth and tenth graders for most categories. Tenth graders tended to give more differentiated responses (e.g., multiple locations, multiple stock sizes). The most elaborate conceptions came from a sixth grader (Mark) with regular primary experiences on an alpine pasture.

**Clinical Implications:** This study has no direct clinical implications but provides educational recommendations for ESD. To promote SDG 12 (responsible consumption and production), teachers should address the relationships between milk production volume, herd size, husbandry practices, and the biological process of lactation. Field trips to dairy farms with proper preparation and follow-up can counteract romanticized conceptions. The study's small sample size (n=8) and qualitative design limit generalizability; larger quantitative studies are needed. The authors note that secondary school experiences with agricultural topics appear to have limited lasting impact, as tenth graders had vague recollections of classroom instruction on dairy farming.