Measuring liveweight changes in lactating dairy ewes with an automated walk-over-weighing system

Monitoring liveweight (LW) is an important part of sound management practices at the individual and flock level (e.g., controlling for nutritional status based on body condition, reproduction, health-related issues), but it time consuming stressful. To our knowledge, no literature has reported evaluation automated weighing systems in dairy sheep as alternative to conventional static scales. The objective this research was evaluate practical feasibility using walk-over-weighing (WoW) prototype measure daily LW changes ewes without human intervention. We used adult Lacaune 2 complementary trials conducted indoors. Trial 1 aimed evaluating repeatability, precision, accuracy measures recorded WoW scales compared with a scale (the gold standard). Forty-two (LW ± standard deviation = 71.3 10.4 kg) were randomly drafted from main 1-day session. trial included 3 passages. In each passage, weighed first scale; once position achieved recorded, they continued circuit immediately traversed record. demonstrate device under real-world conditions sheep-farming system. installed exit race milking parlor evaluated over 7 wk mid lactation (n 93; 78.5 8.1 kg). Once acclimated system, group 48) receive same feeding regimen (controls), other 45) underwent challenge [challenged; undernutrition then back control (refeeding) wk]. ability detect small LW. collected data (2 weighings per ewe day) after sessions (morning evening). also obtained values by week. system showed substantial agreement when assessed Lin's concordance correlation coefficient Bland Altman's method, largely due high repeatability. adequate detecting variations during refeeding periods. Misbehaviors resulted spurious 2, requiring us use filtration methods exclude outlier weights allow meaningful assessment changes. here conventionally farms. If raw applied, could contribute close (daily) monitoring operator intervention (i.e., voluntary weighing) taking animal welfare into account stress related session scales).