PSII-7 Feed Intake and Behavioral Responses of Mature Rams Provided Feed Containing Phenylthiocarbamide

Abstract Bitter taste perception has been studied in various species, including humans, using the synthetic compound phenylthiocarbamide (PTC). Human of PTC is linked to ability bitter foods. Sheep express varying levels aversion delivered drinking water. The objective this study was determine effects feed on dietary intake and behavior mature rams. We hypothesized that rams previously classified into PTC-taster categories PTC-spiked water would rank similarly when added feed. Mature Targhee, Rambouillet, Polypay, composite-breed rams, as either super- (n = 3), intermediate- 5), or non-PTC tasters 4), were subjected 4-d acclimation 6-d test phases. Alfalfa (70%), corn (15%), beat pulp (15%) meal mixed with ethanol (150 g/kg, fed) only (control) solubilized create three pelleted (6.3 mm) diets (110, 220 330 mg PTC/kg feed, fed). Rams received control (0.87% BW) daily for 30 min a side-by-side presentation, which replicated each concentration. Feeding duration, number bucket approaches switches, sniffs, drinks, lip smacks licks, head bobs, jerks, shakes recorded throughout trial video surveillance. For concentration, consumption similar (P 0.22) measured percentage total diet (control + PTC) consumed. Individual intakes ranged from 1.5 89.8% CV 110, mg/kg increased 22.4 34.1 36.1%, respectively. Intake offered decreased 0.01) between 110 (80.9 ± 3.2%) (72.3 3.2%), while (78.4 intermediate ≥ 0.06). by average relative 1.0 SD population mean (50.2 7.5%). Using method, 7 12 former classification established Total feeding duration less ≤ 0.03) (805.4 18.2 s) compared (858.1 19.3 (862.7 19.5 s). switched more 0.02) (21.2 10.0) than (16.4 7.8) (18.4 8.4). These results suggest sheep perceive exhibit variable responses incorporated More research needed identify mechanisms bitter-tasting feeds.