Exploring research dynamics in pasture-based automatic milking systems: a bibliometric approach

The worldwide adoption of automatic milking systems (AMSs) has expanded, attracting growing interest from researchers. Although several reviews have already been carried out regarding the features of AMS in confined systems, a comprehensive bibliometric analysis of the literature on automated milking in pasture-based systems is still lacking. Therefore, this review set out to provide a bibliometric approach focused on pasture-based AMS to explore and map the extent of research in the scientific literature. Initially, a comprehensive search was carried out in the Web of Science and Scopus databases. Then, a four-step PRISMA evaluation was applied on 235 identified articles, resulting in a final sample of 45 articles. Most studies were conducted in Europe (44%), in research herds (79%), involving Holstein-Friesian cows (76%), using automated milking from Lely (57%) and DeLaval brands (30%). White clover and perennial and annual ryegrass are the most commonly used pastures among the countries (87.5% vs. 75%). The main topics (33%) investigated over studies were milk production, composition and efficiency of AMS on pasture, followed by animal behaviour (27%), animal nutrition (16%), heat stress (9%), methane emissions (7%), health disorders (2%), economic viability (2%), somatic cell count and mastitis (2%) and energy consumption (2%). Concentrate allocation and heat stress were identified as emerging research areas that deserve greater attention in future studies. This study contributes to our understanding of scientific developments, trends and research gaps regarding pasture-based AMSs.