Technical note: Evaluation of an alternative automatic heating-stirring system in the determination of in vitro ruminal dry matter digestibility of forages using the Tilley and Terry method
Resumo
This study evaluated an alternative heating-stirring system in the determination of in vitro ruminal digestibility of dry matter (IVRDMD) of forages using the Tilley and Terry (TT) method. For this purpose, the IVRDMD of three forage species (Marandu, Tifton 85, and Mombasa) was determined by incubating 500 mg of each dried and ground (1 mm) forage in 50-mL rumen inoculum during 48h, followed by quantification of the incubation residue. Two heating-stirring systems were used: i) heating in a water bath at 39°C with manual stirring every two hours (i.e., traditional system); and ii) heating in an oven with controlled temperature at 39°C and automatic agitation (44 rpm; alternative system); there was no effect of the interaction between the heating-stirring system and the type of forage (p = 0.829) on the IVRDMD of forages. The type of heating-stirring system (p = 0.422) did not affect the IVRDMD of forages. Nevertheless, the IVRDMD values of Marandu grass (system i = 598.7 g kg-1 vs system ii = 599.4 g kg-1) were greater (p < 0.001) than Tifton 85 (system i = 392.1 vs g kg-1 vs system ii = 370.7 g kg-1) and Mombasa (system i = 397.4 g kg-1; system ii = 369.7 g kg-1) grasses. In conclusion, the obtained data indicate that the alternative heating-stirring system produces similar results to those obtained using the traditionally heating-stirring system during the determination of the IVRDMD of forages.
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Referências
Camacho, L. F., Silva, T. E., Palma, M. N. N., Assunção, A.S., Rodrigues, J. P., Costa e Silva, L. F., & Detmann, E. (2019). Evaluation of buffer solutions and an addition for estimating the in vitro digestibility of feeds. Journal of Animal Science, 97(2), 922-931.
Castagnara, D. D., Neres, M. A., Oliveira, P. S. R., Jobim, C. C., Três, T. T., Mesquita, E. E., & Zambom, M. A. (2012) Use of a conditioning unit at the haymaking of Tifton 85 overseeded with Avena sativa or Lolium multiflorum. Brazilian Journal of Animal Science, 41(6), 1353-1359.
Cook, C. W. (1964). Symposium on Nutrition of Forages and Pastures: Collecting forage samples representative of ingested material of grazing animals for nutritional studies. Journal of Animal Science, 23, 265-270.
Detmann, E., Souza, M. A., Valadares Filho, S. C., Queiroz, A. C., Berchielli, T. T, Saliba, E. O. S., ... Azevedo, J. A. G. (2012). Methods for food analysis - INCT - Animal Science. Visconde do Rio Branco, MG: Suprema.
Di Marco, O. N., Ressia, M. A., Arias, S., Aello, M. S., & Arzadúnc, M. (2009). Digestibility of forage silages from grain, sweet and bmr sorghum types: Comparison of in vivo, in situ and in vitro data. Animal Feed Science and Technology, 153(3-4), 161-168.
Forejtová, J., Lád, F., Třináctý, J., Richter, M., Gruber, L., Doležal, P., Homolka, P., & Pavelek, L. (2005). Comparison of organic matter digestibility determined by in vivo and in vitro methods. Czech Journal of Animal Science, 50(2): 47-53.
McDougall, E. I. (1948). Studies on ruminant saliva. 1. The composition and output of sheep's saliva. Biochemical Journal, 43, 99-109.
Mabjeesh, S. J., Cohen, M., & Arieli, A. (2000). In Vitro Methods for Measuring the Dry Matter Digestibility of Ruminant Feedstuffs: Comparison of Methods and Inoculum Source. Journal of Dairy Science, 83(10), 2289-2294.
Maia, G. A., De Pinho Costa, K. A., Da Costa, S. E, Epifanio, P. S., Neto, J. F., Ribeiro, M. G., ... Gonçalves, W. G. (2014). Yield and chemical composition of brachiaria forage grasses in the offseason after corn harvest. American Journal of Plant Sciences, 5, 933-941.
Russouw, A., Raffrenato, E., Chaucheyras-Durand, F., & Chevaux, E. (2016). On the way to optimize the two stage Tilley and Terry technique for a more accurate in vitro assessment of rumen modifiers. Journal of Animal Science, 94(Supp 5), 795-796.
Tilley, J. M. A., & Terry, R. A. (1963). A two-stage technique for the in vitro digestion of forage crops. Grass and Forage Science, 18(2), 104-111.
Van Soest, P. J. (1994). Nutritional Ecology of the Ruminant (2nd ed.). Ithaca, NY: Cornell University Press.
Vargas, J. A. C., & Olivera, M. (2017). Polyunsaturated fatty acid type and ratio in lipid supplements alter the in vitro dry matter digestibility of kikuyu grass (Cenchrus clandestinus). Livestock Research for Rural Development, 29(7).
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