Effect of placement weight and days on feed on feedlot cattle performance and carcass traits

Extending the feeding period beyond 8.0 mm of subcutaneous fat reduces feed efficiency without improving meat colour and tenderness of non-implanted feedlot steers

“…The observed linear increase in DP with extended feeding time (0.0378% DP per day) was consistent with the observations of other authors (0.0229-0.0325% DP per day; Vasconcelos et al, 2008;Volpi-Lagreca et al, 2021). This rise in DP led to a higher carcass transfer with longer feeding periods.…”

“…In contrast, non-carcass components showed a slower growth rate in relation to empty body weight. Accordingly, Volpi-Lagreca et al (2021) found a reduction in liver, spleen, kidney, rumen, omasum and abomasum weights, as a percentage of body weight, when DOF increased.…”

“…As described above, the decrease in efficiency could be attributed to reduced SBW gain, increased maintenance energy costs and higher energetic cost of gain (NRC, 1996). Volpi-Lagreca et al (2021) reported no differences in SBW feed conversion between the 6.0 and 11.5 mm ultrasound FT endpoints (54 to 111 DOF), followed by an increase when animals where fed up to the 13.0 mm ultrasound FT endpoint (145 DOF). However, feed conversion was calculated from the beginning of the adaptation period to the harvest of each treatment.…”

“…Nonetheless, as some markets seek high marbling levels, animals are often kept on feed for longer periods. This increases meat marbling, but also other undesired fat deposits reducing feed efficiency on a body weight basis (Wilken et al, 2015;Volpi-Lagreca et al, 2021). However, as dressing percentage (DP) increases with the duration of the feeding period (Bruns et al, 2004;Vasconcelos et al, 2008), the reduction in feed efficiency is less significant ABSTRACT.…”

“…when carcass weight (CW) is used instead of body weight (Wilken et al, 2015;Volpi-Lagreca et al, 2021).…”