Associative Effect of Ingredient Sources on the Partial Mixed Ration and TMR Silages for Feedlot Beef Cattle Diets in Brazil

Associative Effect of Ingredient Sources on the Partial Mixed Ration and TMR Silages for Feedlot Beef Cattle Diets in Brazil Chengqiang Wang, Greiciele de Morais, Álvaro Bernardo da Silva Neto, Aline Venância Andrade, Ariádna Patricia Ribeiro, Luiz Gustavo Nussio Department of Animal Science, Luiz de Queiroz College of Agriculture, University of São Paulo, Piracicaba, São Paulo, Brazil. Keywords: Partial mixed ration silage, TMR silage, Effluents, Water holding capacity, Wet distillers bran plus solubles. Introduction Corn-based ethanol industry evolved in Brazil reaching 22 plants in 2024, producing together 5 million ton of DDG (dried) and WDG (wet) coproducts. Besides the huge increase of DDG for ruminant and monogastric diets, it is still there the offering of wet distillers grains with solubles (WDGS) as a diet ingredient, mostly for finishing beef cattle. Its typical high moisture content (60-65%) and high solubles pose a challenge to logistics on hauling, storage and conservation at the farm level. Cottonseed hulls and soybean hulls are also available in large quantities in Brazil. Therefore, wet distillers bran with solubles (WDBS) might be conserved combined with these drier ingredients to form a stable total mixed ration (TMR) silages or either partial mixed ration (PMR) silages to reduce conservation losses during storage and become more attractive to compose beef cattle finishing diets. When crop by-products are mixed with WDBS for silage, it can not only neutralize the disadvantage of excessive moisture but also improve the palatability of crop by-products (Yuan et al., 2015) as an associative effect. At the same time, through reducing effluents could reduce the losses of nutrients and environmental impact. The aim of this study was to identify strategies to control the spoilage and effluent losses in WDBS combined with dry ingredients for silage production. Materials and methods The experiment was designed into 5 treatments: TMR silage as positive control (50% WDBS, 7% tropical grass silage, 9% cottonseed hulls (CH), 12% soybean hulls (SH), 19% ground corn (CORN) and 3% minerals-vitamins premix); WDBS as negative control (WDBS exclusive); WDBS ensiled with cottonseed hulls (WDBS+CH, 85% WDBS+15% CH); WDBS ensiled with soybean hulls (WDBS+SH, 81% WDBS+19% SH); WDBS ensiled with ground corn (WDBS+CORN, 72% WDBS+28% CORN). CH, SH and CORN were mixed and ensiled according to the inclusion rate defined on the TMR silage treatment, which is based on a typical beef cattle finishing diet in Mato Grosso, Brazil. All treatments were mixed thoroughly and then packed into the 20 L polyethylene bucket silo during either 60 or 120 days with four replicates. The treatments were analyzed in a 5×2 factorial scheme (five treatments and two storage lengths). The statistical analysis was carried out using the MIXED procedure of SAS 9.4, and the model tested the effects of treatment, time and the interaction between these factors. Means were considered different when p<0.05 by Tukey test. Results TMR treatment presented the highest lactic acid bacteria (LAB) counts, acetic acid and propionic acid concentration (p<0.01), highest pH (p<0.01), lowest dry matter (DM) losses(p<0.05) and effluent production (p<0.05) compared with other treatments. WDBS+SH had higher lactic acid concentration with decreased DM losses and effluents production among the other PMR silages. Prolonged length of storage increased pH, DM losses and effluents production. Fermentation and losses in silages, measured during the ensiling period and mixed either as TMR or PMR silages were dependent of the associative effects of the individual Water Retention Capacity (WRC) from single ingredients. Conclusions The results suggested that the strategy of mixed ensiled high moisture WDBS with other feedstuff was an effective method of preserving WDBS. All WDBS-based PMR silage were well-preserved with a low pH and high aerobic stability. WDBS+SH treatment reached the lowest dry matter loss and effluent net flow. WDBS-based TMR showed a relatively higher pH, however, it did not affect the fermentation quality and aerobic stability, moreover, showed lower dry matter loss and effluent production than WDBSbased PMR. Table 1. Fermentative profile of TMR silage and PMR silage. 1 TMR, Total mixed ration; WDBS, ensiling wet distillers bran plus solubles alone; WDBS+CH, mixed ensiled 85% WDBS with 15% cottonseed hulls; WDBS+SH, mixed ensiled 81% WDBS with 19% soybean hulls; WDBS+CORN, mixed ensiled 72% WDBS with 28% ground corn. 2 SEM, Standard error of the mean.3 T, Treatment effect; L, Length of storage effect; T×L, Interaction effect between treatment and length of storage Values followed by different lowercase letters indicate statistical difference between treatments. Values followed by different capital letters indicate statistical difference between length of storage. Both differ statistically using the Tukey test at 5% probability. Table.2. Effluents and dry matter losses of TMR silage and PMR silage. Items Length of storage (d) Treatments1 SEM2 P-value3 TMR WDBS WDBS+ CH WDBS+ SH WDBS+ CORN Mean T L T×L pH 60 4.34Aa 3.73Bc 3.78Bbc 3.79Bb 3.74Bc 3.87 0.01 <0.0001 <0.0001 <0.0001 120 4.34Aa 3.87Ab 3.92Ab 3.92Ab 3.88Ab 3.99 Mean 4.34 3.80 3.85 3.85 3.81 - Lactic acid, % DM corr 60 4.74 4.95 3.69 5.07 4.48 4.59B 0.61 0.0269 <0.0001 0.1284 120 5.49 6.08 6.14 8.64 7.51 6.77A Mean 5.12ab 5.52ab 4.91b 6.85a 5.99ab - Acetic acid, % DM corr 60 0.37 0.30 0.24 0.30 0.31 0.30B 0.03 0.003 0.0051 0.4657 120 0.40 0.31 0.31 0.40 0.36 0.36A Mean 0.39a 0.31b 0.27b 0.35ab 0.33ab - Propionic acid, mg/kg 60 383 140 130 134 120 181B 17.9 <0.0001 0.0133 0.1672 120 351 145 176 172 152 199A Mean 367a 143b 153b 153b 136b - Butyric acid, mg/kg 60 117Aa 8.50Abc 3.25Ad 3.75Acd 12.5Ab 29.0 3.22 <0.0001 0.6944 0.0176 120 105Aa 11.0Ab 3.25Ac 6.00Abc 5.00Bc 26.1 Mean 111 9.75 3.25 4.88 8.75 - Ethanol, % DM corr 60 0.11Aa 0.10Aa 0.10Aa 0.13Ba 0.11Ba 0.11 0.01 <0.0001 <0.0001 0.0007 120 0.10Ab 0.12Ab 0.13Ab 0.20Aa 0.19Aa 0.15 Mean 0.10 0.11 0.11 0.17 0.15 - Items Length of storage (d) Treatments1 SEM2 P-value3 TMR WDBS WDBS+ CH WDBS+ SH WDBS+ CORN Mean T L T×L DM losses,% 60 1.80Ac 5.05Bb 7.85Aa 3.83Bbc 6.33Bab 4.97 0.61 <0.0001 0.005 0.0089 120 0.58Ab 7.48Aa 7.65Aa 6.28Aa 8.75Aa 6.15 Mean 1.19 6.26 7.75 5.05 7.54 - Production of effluent (g/kg, FM)4 60 26Ac 120Ba 101Aab 40Bc 86Bb 74 5.30 <.0001 0.007 0.0002 120 35Ad 180Aa 115Ab 57Ac 120Ab 101 Mean 31 150 108 48 103 - 1 TMR, Total mixed ration; WDBS, ensiling wet distillers bran plus solubles alone; WDBS+CH, mixed ensiled 85% WDBS with 15% cottonseed hulls; WDBS+SH, mixed ensiled 81% WDBS with 19% soybean hulls; WDBS+CORN, mixed ensiled 72% WDBS with 28% ground corn. 2 SEM, Standard error of the mean. 3 T, Treatment effect; L, Length of storage effect; T×L, Interaction effect between treatment and length of storage. 4 In fresh matter (FM). Values followed by different lowercase letters indicate statistical difference between treatments. Values followed by different capital letters indicate statistical difference between length of storage. Both differ statistically using the Tukey test at 5% probability. References Yuan, X., Guo, G., Wen, A., Desta, S. T., Wang, J., Wang, Y., & Shao, T. (2015). The effect of different additives on the fermentation quality, in vitro digestibility and aerobic stability of a total mixed ration silage. Animal Feed Science and Technology,207, 41-50. Contact Information: Luiz Gustavo Nussio, Email: [email protected]