LAUSR

The prevalence (PRE) of antibodies against bovine viral diarrhea (BVD) was determined in 421 cows from 24 herds located in 11 Municipalities of the States of Puebla, Tabasco and Veracruz, Mexico. In addition, the influence of the presence of antibodies against bovine viral diarrhea on pregnancy rate (PR) was evaluated. Before the study, the herds were never vaccinated against BVD. Blood samples were taken from each cow twice, with an interval of 3.5 to 4.0 mo. The presence of antibodies was determined with the ELISA test. At the first sampling, Puebla (51.4 %) and Tabasco (49.7 %) showed lower PRE ( P 0.05) to that of cows with antibodies (57.3 vs 53.5 %). In conclusion, 1) Veracruz showed higher PRE than Puebla and Tabasco; 2) All the herds had antibodies against BVD, suggesting that the BVD virus is amply distributed in the three States; 3) A great variation existed between herds and between municipalities, with PRE being close to 100 % in several cases; 4) The presence of antibodies against BVD did not influence pregnancy rate.