Sampaio, Alexandre Amstalden MoraesDe Figueiredo Vieira, Paulo [UNESP]De Brito, Rodolfo Marques [UNESP]2022-04-292022-04-292000-03-01Revista Brasileira de Zootecnia, v. 29, n. 2, p. 598-602, 2000.0100-4859http://hdl.handle.net/11449/230963The objective of this trial was to evaluate the in vitro ammonia (N-NH 3) production in fermentation of diets with different protein sources (dry yeast, urea and cottonseed meal) used for ruminants diets. The data relative to the N-NH 3 production measured in the first hour of incubation, showed differences between diets with cottonseed meal and dry yeast, compared with diets with urea, with values of 7.52; 8.66; and 29.84 mg N-NH 3/100 mL of ruminai fluid, respectively. The same pattern was observed until 12 hours of fermentation, with values of 1.05; 1.57; and 8.57 mg N-NH 3/100 mL. The analysis of data related to the 12 hourly sample of fermentation showed the trend of decreasing N-NH 3/100 mL concentration of ruminal fluid, reaching the lower values on 12 hours of fermentation.598-602porAmmoniaCottonseed mealDry yeastProtein sourcesRuminal fermentationUreaArtigo2-s2.0-0348246834