Selected ruminal variables and purine urinary excretion rate of steers subjected to feeding, fasting, and re-feeding conditions - Ortolani, Enrico Lippi; Maruta, Celso Akio; Barreto Júnior, Raimundo Alves; Mori, Clara Satsuki; Antonelli, Alexandre Coutinho; Sucupira, Maria Cláudia Araripe; Minervino, Antonio Humberto Hamad (Polish Journal of Veterinary Sciences, 2022)