Bulk milk and farms characterization in the Parmigiano Reggiano Consortium area: the INTAQT project

Parmigiano Reggiano (PR) is probably the most valuable Italian cheese, produced under the regulations of a specific Consortium that supervises one of the main dairy chain in Italy. The study aimed to characterize structure, management and milk traits (milk yield, kg/d per cow –MY, protein content, % -CP, and fat content, % -FAT) of the PR-producing farms enrolled in the INTAQT project. Data originated from farm inspections (altitude zone -AZ, herd size, housing type, genetic type of cows -GT, use of total mixed rations -TMR, proportion of concentrate inclusion in the lactating cow diets -CONC) and official milk recording system (test-day MY, CP, FAT). All farms were scored for animal welfare related features (management -A, structure -B, and animal-based measure -C; 0-100 score range per category) according to the official national method for animal welfare assessment. A total of 4,558 milk records from 804 farms were considered. Altitude zone was classified as mountain and plain, GT as mostly Brown Swiss, mostly Holstein Friesian (HF+), only Holstein Friesian (HF) and local breeds, CONC into 3 classes (<25, 25-55 and >55% of the average dry matter) and welfare scores into 3 classes (mean±0.5 SDs). Test-day were grouped as seasons (SE; winter, spring, summer). Milk yield, CP and FAT were analysed with a mixed model with AZ, GT, CONC, welfare A, B, C scores and SE classes as fixed effects and farm as random one. All the fixed effects except SE were nested into farm. Farms were mostly located in the plain (77% of farms), with free-stall housing (68%), rearing HF cows (41% HF; 45% HF+) and not using TMR (44%). Lactating cows averaged 108±106 and were fed diets that included 42±8% CONC. Welfare scores A, B and C averaged 78±9, 71±10 and 79±6, respectively. Most of the fixed effects affected MY, with greater values for plain-located farms, rearing HF cows, with TMRs, high levels of CONC, scores A and C. Milk protein was affected by GT, TMR, score C and SE, whereas FAT by AZ and SE. These results could contribute to drawing interventions aiming to improve both intrinsic quality of milk destined for cheese production and extrinsic one related to environmental sustainability and animal welfare.