2 Effects of Multiple Bovine Appeasing Substance Administration During a 42-Day Preconditioning Program on Physiologic, Health, and Performance Responses of Feeder Cattle

Abstract This experiment evaluated the effects of multiple bovine appeasing substance administration during a 42-day preconditioning program followed by feedlot receiving period on productivity, health, and physiological variables feeder cattle. Ninety recently weaned calves were obtained from Red Bluff Ranch (Norris, MT). All weighed (prior to transport). Calves loaded into livestock trailer, transported for 70 km, unloaded at Bozeman Agricultural Research Teaching Farm program. Upon arrival, calf body weight was recorded, both pre- post-transport averaged used as weaning initial weight. sorted weight, sex, age, assigned receive 1) (d0), d 14, 28, before transport entry (d 42; BAS; RSEA Group, Quartier Salignan, France), or 2) placebo (diethylene glycol monoethyl ether; CON). Treatments (5 mL) applied topically nuchal skin area each animal every 14 period. within treatment groups ranked BW, allocated 1 18 drylot pens. On day 42, combined group, 2 different single double-deck commercial trailers, 1000 km (approximately 16 h). arrival (day 43), same feedyard with pen distribution prior fed ad libitum TMR diet. Blood samples collected 0 (weaning), 3, 7, 21, 42 transport), 43 (feedlot arrival), 46, 50, 57, 64 90. Average daily gain final BW did not differ (P > 0.52) between BAS CON in phases. No also detected 0.44) intake any Overall feed efficiency 0.54). = 0.98) plasma concentrations cortisol. A × interaction < 0.001) haptoglobin concentrations, which greater 0.01) 3 7 vs. calves. Therefore, applications mitigated an acute-phase response associated accumulative stress caused weaning, transport, vaccination.