Phosphorus supplementation with or without other minerals, ionophore and antibiotic did not affect performance of Nellore bulls receiving high-grain diets, but increased phosphorus excretion and dietary costs

Autor(es)

Souza, V. C. ^[1] ; Malafaia, P. ^[2] ; Vieira, B. R. ^[1] ; Granja-Salcedo, Y. T. ^[1] ; Berchielli, T. T. ^{[1, 3]}

Afiliação do(s) autor(es)

^[1] UNESP Univ Estadual Paulista, Dept Anim Sci, Campus Jaboticabal, BR-14884900 Sao Paulo - Brazil

^[2] UFRRJ, Inst Anim Sci, Dept Anim Nutr & Pastures, BR-23853000 Seropedica, RJ - Brazil

^[3] Univ Fed Vicosa, CA, INCT, Dept Anim Sci, Ave Peter Henry Rolfs S-N, Campus Univ, BR-36570000 Vicosa, MG - Brazil

• Tipo de documento: Artigo Científico
• Fonte: ANIMAL PRODUCTION SCIENCE; v. 58, n. 5, p. 871-877, 2018.
• Citações Web of Science: 2

Resumo

This study was conducted to evaluate the effect of phosphorus (P) supplementation, with or without addition of other minerals, ionophore and antibiotic, on performance, P utilisation and profitability in finishing Nellore bulls in a feedlot. Forty-two animals, with an initial bodyweight of 296 +/- 25 kg, were distributed in a completely randomised design consisting of three treatments and 14 replicates. The treatments were without P supplementation (T-1), commercial mineral supplement specific for feedlot cattle (T-2) and supplementation with dicalcium phosphate (T-3). The T-3 was formulated to achieve a P concentration similar to that of T-2, but without adding other additives (e.g. vitamins, ionophores, yeast and chelates) in the mineral mix. The P concentrations were 2.4, 4.2 or 5.0 g P/kg of dry matter (DM), respectively, for T-1, T-2 and T-3. The diet, on a DM basis, comprised sugarcane bagasse (200 g/kg) plus concentrate (800 g/kg). The DM, crude protein and neutral detergent fibre intakes and apparent DM digestibility were similar among the three treatments (P > 0.05). Despite the numerical difference on P concentration in T-2 and T-3 treatments, P intakes were similar in these treatments. The addition of commercial mineral supplement specific for feedlot cattle or dicalcium phosphate in diets increased P excretion in the faeces and urine, increased P retention and reduced the profitability of the feedlot. Performance and carcass traits were not affected by diet P concentrations (P > 0.05). The profit per head in T1 treatment was US\$13.7 and the addition of the dicalcium phosphate and mineral mix in T2 and T3 did not result in profit, these treatments gave economic losses of US\$6.80 and US\$6.20 per head, respectively. Under Brazilian conditions, feedlot Nellore cattle fed high-grain diets do not require any additional mineral supplements. P concentration of 2.4 g/kg DM, as used in the control diet, was adequate to ensure animal performance and reduce faecal P excretion, which is in agreement with NRC and CSIRO recommendations. Lower values may also be appropriate, but were not tested here. (AU)

• Processo FAPESP: 14/08935-1 - Balanço nutricional, desempenho, parâmetros ósseos, aspecto econômico e qualidade da carne de bovinos Nelore submetidos ou não à suplementação fosfórica durante o período de confinamento
• Beneficiário: Vinícius Carneiro de Souza
• Linha de fomento: Bolsas no Brasil - Mestrado