To investigate the impact of post-extraction algal residue (PEAR) on nutrient utilization, carcass performance, and beef tenderness and flavor in finishing steers, eighteen Angus x Hereford steers were used in a three-phase study. Treatments consisted of PEAR hand-mixed into the diet at 1.0 kg OM/d (PEAR), 1.0 kg OM/d glucose infused ruminally (GR) or abomasally (GA). Infused steers were fitted with ruminal cannulae, allowing continuous infusion of glucose via anchored infusion lines. Steers were adapted to housing and basal diet prior to starting; subsequently, treatments were applied approximately 35 d, until harvest. Intake and digestion were determined from d 27 to 31 using fecal grab samples. Steers were harvested on d 34 to 36; 2 d post-harvest, carcass measurements were collected and strip steaks were obtained from each carcass from GA, GR, and PEAR treatments. Three d post-harvest, beef subprimals and subcutaneous fat from the chuck and round of each carcass from GR and PEAR treatments were collected, and 2 d prior to sensory evaluation, subprimals were further processed into ground chuck and round, respectively.
Greater DMI was observed for PEAR (13.0 kg/d) than GR (10.3 kg/d; P < 0.05);
DMI for steers receiving GA (11.2 kg/d) was intermediate and not different from either PEAR or GR (P >= 0.14). Digestible OM intake was similar among treatments and averaged 8.8 kg/d (P = 0.51). Digestion of GE was 72.9, 82.6, and 80.9% for PEAR, GA, and GR, respectively (P < 0.01). Steers fed PEAR had greater marbling scores (Mt^20) than GA (Sm^63) and GR (Sm^52; P = 0.01). Accordingly, USDA Quality Grade was greater for PEAR than GA and GR (Ch^40, Ch^21, and Ch^17, respectively; P = 0.01). There was no difference in USDA Yield Grade or HCW between treatments (P >= 0.66). No off-flavors were detected by trained sensory panel analysis in strip steaks from GA, GR, or PEAR (P > 0.05). No significant differences for overall like, overall flavor like, beef flavor like, or juiciness like were observed in ground round or ground chuck from PEAR or GR fed steers (P >= 0.17).
- Sawyer, Jason Associate Professor and Associate Department Head