Performance, digestibility, microbial production and carcass characteristics of feedlot young bulls fed diets containing propolis

Abstract

ABSTRACT. The objective was to evaluate the effect of propolis-based products (PBP) on performance, digestibility, microbial production and carcass characteristics of feedlot young bulls. Twenty-seven crossbred young bulls were used, with 353 ± 28 kg of body weight in a completely randomized experimental design, divided in three treatments: two diets with PBP with different dosages (PBP1= 0.018 mg g -1 and PBP2= 0.036 mg g -1 of total flavonoids in chrysin) and control diet (CON). To determine total digestibility, the indigestible dry matter was used as an internal marker, while microbial production was estimated from purine derivatives in urine, collected by the spot method. The evaluated carcass characteristics were: hot carcass weight, dressing percentage, conformation, Longissimus muscle area, fat thickness, colour, texture, marbling, pH, cushion thickness and percentages of muscle, bone and fat. The studied variables were subjected to analysis of variance with 5% probability. The addition of propolis had no effect on DM and nutrients digestibility (except the ADF, which was higher) or efficiency of microbial synthesis. Carcass characteristics were not affected by the experimental treatments. The PBP in the used dosages should be reviewed and higher dosages should be tested.Keywords: additive, flavonoids, meat quality, microbial efficiency, ruminant.Desempenho, digestibilidade, produção microbiana e características de carcaça de bovinos confinados que receberam dietas contendo própolis RESUMO. Objetivou-se avaliar o efeito de produtos à base de própolis (PBP) sobre o desempenho, digestibilidade, produção microbiana e características de carcaça de bovinos confinados. Foram utilizados 27 bovinos com 353 ± 28 kg de peso corporal em um delineamento inteiramente casualizado dividido em três tratamentos: duas dietas contendo PBP em diferentes dosagens (PBP1 = 0.018 mg g -1 e PBP2 = 0.036 mg g -1 de flavonoides totais em crisina) e dieta controle (CON) sem adição de própolis. Para a determinação da digestibilidade total, a matéria seca indigestível foi usada como marcador interno, enquanto a produção microbiana foi estimada pelos derivados de purina na urina, coletadas pelo método spot. As características de carcaça avaliadas foram: peso de carcaça quente, rendimento de carcaça quente, conformação, área de olho de lombo, espessura de gordura, coloração, textura, marmoreio, pH, espessura de coxão e percentagens de músculo, osso e gordura. As variáveis estudadas foram submetidas à análise de variância com 5% de probabilidade. A adição da própolis não teve efeito sobre a digestibilidade da MS e nutrientes (exceto para FDA, que foi maior) e eficiência de síntese microbiana. As características de carcaça não foram afetadas pelos tratamentos experimentais. As dosagens utilizadas nos PBP devem ser revistas e dosagens mais elevadas devem ser testadas.Palavras-chave: aditivo, flavonoides, qualidade de carne, eficiência de síntese microbiana, ruminante.

Effects of phenolic compounds in propolis on digestive and ruminal parameters in dairy cows

“…Microbial protein synthesis and its efficiency were not affected by inclusion of propolis in the diet, similarly to what was observed in previous studies (Valero, 2010;Simioni, 2011;Aguiar et al, 2012). In dairy cows, allantoin and uric acid are secreted in the milk, and the amount secreted daily is equivalent to approximately 5% of the purine derivatives (PD) excreted in urine (Chen and Gomes, 1992).…”

“…The observation that the total digestibility of CP was higher in the PBP B1 than in the PBP C1 treatment (P<0.05) was in contrast with the results of previous studies on PBP, which detected no significant differences between various extracts and/or dosages of PBP (Valero, 2010;Simioni, 2011; Aguiar et al, 2012). However, effects on the ruminal metabolism of CP as well as an increase in microbial protein flow to the intestine were observed (Prado et al, 2010).…”

“…In general, PBP do not appear to affect feed intake when propolis is supplied in the form of powder, as verified in feedlot cattle diets (Valero, 2010;Simioni, 2011;Zawadzki et al, 2011;Aguiar et al, 2012) and forage-based diets (Prado et al, 2010). However, Loureiro et al (2007) found a reduction in DM intake in lambs fed diets containing 15 and 30 mg of propolis extract/kg of BW as compared with control.…”

“…However, Aguiar et al (2012) reported no effects of PBP C1 on the total digestibility of DM, OM, NDF, TC, and TDN compared with control treatment. It is noteworthy that the PBP dosage used by Aguiar et al (2012) was two times lower than that used in our study.…”

“…However, Aguiar et al (2012) reported no effects of PBP C1 on the total digestibility of DM, OM, NDF, TC, and TDN compared with control treatment. It is noteworthy that the PBP dosage used by Aguiar et al (2012) was two times lower than that used in our study. In this study, the higher total digestibility of DM and OM linked to the inclusion of PBP B1 rather than PBP C3 could be attributed to the daily supplemented amounts of flavonoids (PBP B1 = 2.81 mg/kg of IDM vs. PBP C3 = 1.22 mg/kg of IDM) and phenolic acids (PBP B1 = 1.00 mg/kg of IDM vs. PBP C3 = 0.71 mg/kg of IDM).…”