Short communication: More meals, better welfare? The role of automatic feeding systems in the fattening of Limousin heifers

This study evaluated the effect of feeding frequency on growth performance, health status, carcass traits, and rumen mucosa disorders in Limousin heifers reared in an intensive production system. The trial was conducted on a commercial farm in northeastern Italy from 2020 to 2022 and involved 37 batches (1152 heifers) imported from France. Animals were assigned to either a conventional feeding system (CFS; n = 603), receiving a total mixed ration (TMR) once daily, or an automatic feeding system (AFS; n = 549), which provided the same diet in multiple daily distributions based on heifers' voluntary intake. Dry matter intake was similar between feeding systems (7.56 vs 7.73 kg/d for CFS and AFS, respectively; P = 0.48). However, AFS heifers achieved this intake with an average of 3.76 +/- 1.18 feed deliveries per day. Average daily gain (1.24 kg/day) and carcass weight (308 kg) did not differ between feeding systems. In contrast, AFS significantly reduced the proportion of animals requiring medical treatment (11.1% vs 20% for AFS and CFS, respectively), particularly for respiratory disorders. Rumen inspections at slaughter revealed a significantly lower prevalence of mucosal lesions in AFS heifers compared to CFS (P < 0.01), including hyperkeratosis (3% vs 18%), signs of ruminitis (15% vs 35%), and star scars (7% vs 18%). These results suggest that increasing feeding frequency through AFS improves animal health and rumen mucosa integrity without compromising growth performance. The observed benefits are likely associated with more stable rumen fermentation patterns and a reduced risk of subacute ruminal acidosis.