title: Effects of supplements containing different additives on nutritional and productive performance of beef cattle grazing tropical grass.
abstract: A grazing trial was carried out to evaluate the inclusion of three feed additives in supplements (crude protein, CP 230 g/kg dry matter, DM) on the performance, voluntary intake, and digestibility of beef heifers grazing Brachiaria decumbens (CP 81 and neutral detergent fiber, NDF 615 g/kg DM). Thirty-five Nellore heifers (21 months of age and 383 ± 6.29 kg of body weight, BW) were used in a completely randomized design. The treatments were as follows: no supplement (control); supplement fed at 1 kg/animal/day without additives (S); supplement with monensin (S + M); supplement with yeast culture (S + YC); and supplement with enzyme complex (S + EC). All of the supplemented heifers had greater (P < 0.1) average daily gain (∼0.186 kg/day) compared to the control treatment (0.014 kg/day). Average daily gain and final BW were similar (P > 0.1) among supplemented heifers. Monensin inclusion in the supplement decreased (P < 0.1) forage DM (expressed as g/kg BW) and NDF intake (expressed as kg/day and as g/kg BW). All of the feed additive inclusions decreased (P < 0.1) NDF digestibility. In conclusion, the heifers' performance was improved by concentrate supplementation. However, the inclusion of additives did not enhance this effect.
authors.affiliation: Animal Science Department, Universidade Federal de Viçosa, Viçosa, MG, 36570-000, Brazil. victor.carvalho@ufv.br.
authors.forename: V V
authors.initials: VV
authors.lastname: Carvalho
authors.affiliation: Animal Science Department, Universidade Federal de Viçosa, Viçosa, MG, 36570-000, Brazil.
authors.forename: M F
authors.initials: MF
authors.lastname: Paulino
authors.affiliation: Animal Science Department, Universidade Federal de Viçosa, Viçosa, MG, 36570-000, Brazil.
authors.forename: E
authors.initials: E
authors.lastname: Detmann
authors.affiliation: Animal Science Department, Universidade Federal de Viçosa, Viçosa, MG, 36570-000, Brazil.
authors.forename: M L
authors.initials: ML
authors.lastname: Chizzotti
authors.affiliation: Animal Science Department, Universidade Federal de Viçosa, Viçosa, MG, 36570-000, Brazil.
authors.forename: L S
authors.initials: LS
authors.lastname: Martins
authors.affiliation: Animal Science Department, Universidade Federal de Viçosa, Viçosa, MG, 36570-000, Brazil.
authors.forename: A G
authors.initials: AG
authors.lastname: Silva
authors.affiliation: Animal Science Department, Universidade Federal de Viçosa, Viçosa, MG, 36570-000, Brazil.
authors.forename: S A
authors.initials: SA
authors.lastname: Lopes
authors.affiliation: Animal Science Department, Universidade Federal de Viçosa, Viçosa, MG, 36570-000, Brazil.
authors.forename: F H
authors.initials: FH
authors.lastname: Moura
mesh_terms: D000821:Animal Feed / Q000032:analysis; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D035201:Brachiaria; D002417:Cattle / Q000254:growth & development / Q000502:physiology*; D004032:Diet / Q000662:veterinary; D004043:Dietary Fiber / Q000378:metabolism; D004063:Digestion / Q000187:drug effects*; D005260:Female; D060434:Herbivory; D008985:Monensin / Q000008:administration & dosage / Q000378:metabolism*; D009584:Nitrogen / Q000378:metabolism; D011897:Random Allocation; D015002:Yeast, Dried / Q000008:administration & dosage / Q000378:metabolism*
chemical_list: D004043:Dietary Fiber; D008985:Monensin; D009584:Nitrogen
keywords: Enzyme complex; Monensin; Pasture; Supplementation; Yeast culture