Uso da capsaicina na recria de novilhos durante as estações quentes do ano

Abstract

Capsaicinoids are the active principle of the by-product of the secondary metabolismo of plants of the genus capsicum, this active is composed of terpenes that confer a pungent action and have antioxidant and antimicrobial power. The objective of this work was to evaluate the inclusion of capsaicin as a capsaicinoid additive in rearing steers in the warm seasons of the year. The experiment was carried out from November 2021 to April 2022, at the Beef Cattle Experimental Unit of the Federal Technological University of Paraná, in the Southwest region of Paraná, Brazil. Nine paddocks with an average area of 0.4 ha of established pasture African Star (Cynodon nlemfuensis vr. Nlemfuensis) were used. Twenty-seven test animals were used, brand new half-Angus castrated animals with an average weight of 292 ± 27 kg and 14 months old. The experimental arrangement was randomized blocks with 3 repetitions, the animals concentrated 0.3% BW daily according to the treatments: SUP (concentrate without addition of capsaicinoids), CAP1 (concentrate+1mg/animal/day of capsaicinoids), CAP2 (concentrated+2mg/animal/day of capsaicinoids). Pasture collections were carried out to determine: offer, forage mass, accumulation rate, total production, botanical composition and nutritive value. Animal performance was evaluated by mean daily gain and gain per area. Concentrate, faeces, urine, ruminal fluid and blood were used to determine intake, urinary urea, ruminal ammonia and blood urea. In addition, observations were made on the thermal behavior (surface and rectal temperature) and microclimate with a mobile metrological station measuring TAR, UR, VV, TRELVA, CTR and THI. Pasture remained similar regardless of treatment, as well as the performance of animals that had an average ADG of 0.559kg. Supplementation with capsaicinoids did not affect the ruminal, blood, urinary and consumption parameters of steers in the recreational phase when supplemented with capsaicinoids at doses of 200 and 2mg. The microclimate data showed a high level of stress regardless of treatment with an average UTI of 79, the surface temperature index showed variation (P<0.05) for supplementation with 2mg/animal/day of capsaicinoids, where the animals had lower temperatures , which are desired and demonstrate the activity of the tested additive, indicating potential for improvement in the thermal comfort of steers in the rearing phase during the hot seasons of the year.