Relationships among milk urea-nitrogen, dietary parameters, and fecal nitrogen in commercial dairy herds.
Can J Vet Res
; 72(5): 449-53, 2008 Oct.
Article
en En
| MEDLINE
| ID: mdl-19086379
ABSTRACT
Our study objective was to determine the ability of milk urea-nitrogen concentrations ([MUN]) to predict fecal nitrogen concentrations ([Fecal N]) in commercial dairy herds. A total of 83 dairy herds were each visited 3 times within 48 h after a monthly herd milk test. For each farm visit, forages were sampled for nutrient analyses, which were entered into a computerized ration evaluator, and fecal samples were taken per rectum from each of 6 cows (2 early-, 2 mid-, and 2 late-lactation). Fecal samples were pooled, mixed, and analyzed for nitrogen content. Fecal nitrogen concentrations were compared with the routinely measured nutritional parameters from the ration evaluation, and the herd average [MUN] for the previous milk test date using mixed linear regression analyses. Total protein supplied in the ration was significantly positively associated with [Fecal N], but herd average [MUN] was not associated (P > 0.10) with [Fecal N].
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Urea
/
Bovinos
/
Proteínas en la Dieta
/
Leche
/
Heces
/
Nitrógeno
Tipo de estudio:
Prognostic_studies
Límite:
Animals
Idioma:
En
Año:
2008
Tipo del documento:
Article