R. Bras. Zootec.11/mar/2025;54:e20240031.
Characterization of dairy farms based on the urea nitrogen content of bulk tank milk in Paraná State, Brazil
Monique Figueiredo-Paludo
, Magali Soares dos Santos Pozza
, Fabio Seiji dos Santos
, Ferenc Istvan Bánkuti
, Maximiliane Alavarse Zambom
, Antonio Leandro Chaves Gurgel
, Jesús Alberto Cardozo Osorio
, Kleves Vieira de Almeida
, José Augusto Horst
, Tairon Pannunzio Dias-Silva
, Luís Carlos Vinhas Ítavo
, Geraldo Tadeu dos Santos
ABSTRACT
The objective of this study was to analyze dairy farm characteristics as a function of milk urea nitrogen (MUN) content in the north and west of the state Paraná, Brazil. Milk urea nitrogen serves as an indicator of protein utilization by cows. In view of the high costs of protein in animal diets, this study evaluated farm characteristics that could influence MUN content. For this, 32 dairy farms were randomly selected for application of a questionnaire assessing qualitative and quantitative variables. Interviews and samplings of bulk tank milk were carried out from October 2018 to October 2019. Three clusters of farms were identified: cluster 1, low MUN content (8.07 mg/dL); cluster 2, high MUN content (21.60 mg/dL); and cluster 3, intermediate MUN content (11.90 mg/dL). Clusters 1, 2, and 3 comprised 19, 4, and 9 farms, respectively. No association was found between MUN content and production system (conventional or agroecological). However, clusters differed significantly (P<0.05) in total number of cows and number of lactating cows. Differences (P<0.05) were also found for milk fat and total solids contents. As MUN is highly influenced by diet protein levels and the analyzed farms used feed based on the same ingredients (corn and soybean), it was not possible to identify which factors influenced MUN content for the studied farm groups.
Palavras-chave: cluster analysis; milk production; milk production systems