This study examined the feeding behavior and growth performance of 31 Hanwoo steers (10 months old; 278 ± 36.13 kg) within a precision livestock farming system using Roughage Intake Control (RIC) units for real-time data collection. Feeding behavior traits were derived from RIC database data using R software, with subsequent analysis conducted using SAS software. The results indicated that the steers visited the feed stations every 31.12 ± 11.99 minutes, averaging 11 ± 3.37 visits/day. Each feeding session lasted an average of 5.90 ± 1.55 minutes, resulting in a feed intake rate of 77.98 ± 22.53 g/min. Mean daily feed intake was 4.76 ± 1.36 kg, and body weight increased consistently, reaching an average of 412 ± 43.44 kg, with an average daily gain (ADG) of 1.26 ± 0.38 kg. Pearson correlation analysis revealed a strong relationship between daily feed intake and visit duration (r² = 0.621; p < 0.01) and an inverse correlation between daily feed intake and feed intake duration (r² = −0.445; p < 0.05), indicating behavioral adaptation. These findings highlight the importance of monitoring feeding behavior traits concerning growth performance, enhancing our understanding of individual animal behavior and its implications for productivity while emphasizing the role of advanced technologies in optimizing feed utilization in confined livestock systems.

The present study evaluated the influence of rumen inocula of different breeds on in vitro fermentation with forage and concentrate substrates. An in vitro was conducted under a 2×2 factorial arrangement with two breeds (Jersey and Holstein steers) and two feed substrates (forage and concentrate) as factors. Three Jersey and 3 Holstein steers were used for the source of in vitro inocula. Metataxonomic analysis of donor rumen fluids showed that Firmicutes was more abundant in Jersey, while Bacteroidetes in Holstein steers. In vitro ㏗ was lower in the fermented inocula of Jersey steers and in the concentrate substrate (p<0.05). After 24h, higher gas production, dry matter, and neutral detergent fiber degradability, and total volatile fatty acids concentration were noted in concentrate substrate (p<0.05). After 24h, inocula of Jersey steers had higher methane and ammonia-nitrogen (p<0.05). After 24h, fermented inocula of Holstein steers produced higher propionate (p<0.05). Conversely, in vitro butyrate production was higher in the fermented inocula from Jersey steers (p=0.072) and in those with concentrate substrate (p<0.05). After 24h, the total bacterial population (log10 c opies) was h igher in t he fermented inocula received from Jersey steers and in the concentrate substrate whereas, Fibrobacter succinogenes and Ruminococcus flavefaciens population were higher (p<0.05) only in the concentrate substrate. Overall results suggest that rumen inocula of different donors influence in vitro fermentation either with forage or concentrate substrates.