R. Bras. Zootec.01/Jan/2009;38(1):159-65.

Microbial protein synthesis and urea nitrogen concentrations in lactating dairy cows fed spineless cactus and different forages based diets

Marcelo de Andrade Ferreira, Renata Rodrigues da Silva, Alenice Ozino Ramos, Antonia Sherlânea Chaves Véras, Airon Aparecido Silva de Melo, Amanda Vasconcelos Guimarães

DOI: 10.1590/S1516-35982009000100020

Five Holstein cows were allotted to a 5 × 5 Latin square design with the objective of evaluating the microbial protein production, using the total excretion of purine derivatives (PD), obtained from spot urine collection, plasma and milk urea and nitrogen (N)-urea. The five treatments contained different forage sources: sugar cane bagasse (CB), tifton hay (TH), elephant grass hay (EH), sorghum silage (SS) and a mixture of sugar cane bagasse + sorghum silage (CBSS). The milk urea (10.98 mg/dL) and N-urea (5.11 mg/dL) concentrations were not influenced by the forage sources, such as plasma urea (28.10 mg/dL) and N-urea (13.09 mg/dL) concentrations. The urinary urea, N-urea, allantoin and PD excretions, the absorbed purine, N-microbial synthesis and milk allantoin concentration remained unchanged. The different forage sources in association with forage cactus did not change the microbial protein production.

Microbial protein synthesis and urea nitrogen concentrations in lactating dairy cows fed spineless cactus and different forages based diets

Comments