1.
J Am Vet Med Assoc
; 223(5): 628-34, 2003 Sep 01.
Article
in English
| MEDLINE
| ID: mdl-12959380
Subject(s)
Animal Nutritional Physiological Phenomena , Cattle/physiology , Dietary Proteins/metabolism , Fertility/genetics , Milk/metabolism , Animal Feed , Animals , Blood Urea Nitrogen , Cattle/blood , Cattle/genetics , Dietary Proteins/administration & dosage , Female , Fertility/drug effects , Fertility/physiology , Lactation/genetics , Lactation/physiology , Milk/chemistry , Pregnancy , Pregnancy Rate , Rumen/metabolism , Urea/analysis
2.
Prev Vet Med
; 60(3): 237-41, 2003 Aug 28.
Article
in English
| MEDLINE
| ID: mdl-12900161
ABSTRACT
Our objective in this cross-sectional study was to determine the seroprevalence in 1996 of commercial dairy herds in central Chile positive to bovine viral diarrhea (BVD) virus, by the detection of antibodies in bulk-tank milk samples. Samples were obtained from 501 dairy farms ( approximately 50,000 cows) from the Metropolitan, VI, VII and VIII regions of Chile. An indirect ELISA was used to detect BVD antibodies. An absorbance (A450) > or = 0.55 was considered positive. The apparent proportion of positive herds ranged from 71.2 to 83% by region and did not differ by region. We concluded that exposure to BVD was widely distributed in the central area of Chile in 1996.
