Síntese de proteína microbiana e balanço de nitrogênio em vacas leiteiras alimentadas com raspa de mandioca e silagem de milho em substituição à palma forrageira

Abstract

The animals were divided into two Latin square 5x5 with the objective of evaluating the effect of substitution of increasing levels (0, 25, 50, 75 and 100% of total DM basis) of forage palm by cassava and corn silage on the nitrogen balance and microbial protein synthesis. For the synthesis of microbial protein were used purine derivatives, estimated their concentrations in urine and milk. There was no effect of the substitution on the total nitrogen intake (419.11 g / day) and nitrogen excretion in urine (56.40 g / day) and milk (87.82 g / day). The excretion of allantoin in the urine (297.89 mmol / day) in milk allantoin (21.22 mmol / day), uric acid (74.18 mmol / day) and purine derivatives total (393.33 mmol / day) and microbial protein synthesis (1585.25 g / day) were not affected by the replacement of forage cactus by cassava scrapings. Under the conditions of this study, both spineless cactus as cassava with maize silage did not influence the efficiency or synthesis PBmic estimated at 138,96 PBmic g / kg of total digestible nutrients, nor nitrogen balance, estimated at 155.35 g / day.