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The effect of the dam–calf relationship on serostatus to Neospora caninum on 20 Costa Rican dairy farms
(Universidad Nacional, Costa Rica, 2003-03-31)
An epidemiological study was conduced on 20 dairy herds previously diagnosed as seropositive
for Neospora caninum. The number of females per farm varies from 41 to 296. All females present
on the farms were bled once in ...
Epidemiología de la leucosis enzoótica bovina en hatos lecheros especializados de Costa Rica
(Universidad Nacional, Costa Rica, 2008-03-25)
En el presente trabajo de investigación participaron 76 fincas lecheras especializadas,
localizadas en las principales zonas lecheras de Costa Rica, en las provincias de San José,
Cartago, Heredia, Alajuela y Guanacaste. ...
Presencia de anticuerpos neutralizantes contra el virus de estomatitis vesicular (serotipos New Jersey e Indiana) en personas residentes en dos zonas lecheras de Costa Rica
(Universidad Nacional, Costa Rica, 2002-12)
La primera parte de esta investigación tuvo como objetivo determinar la prevalencia de anticuerpos contra el virus de estomatitis vesicular, serotipos New Jersey e Indiana, en la población humana de las regiones lecheras ...
Desarrollo e implementación de metodología para optimización del descarte en hatos de lechería especializada de Costa Rica
(Universidad Nacional, Costa Rica, 2007-03)
El objetivo de esta tesis fue desarrollar un modelo bioecónomico para el cálculo de valores económicos
de distintos rasgos productivos en ganado lechero y construir un índice de selección fenotípico que pueda
ser ...
Factors associated with Neospora caninum serostatus in cattle of 20 specialised Costa Rican dairy herds
(Elsevier B.V, 2002-04-15)
Twenty-five specialised Costa Rican dairy farms (located in the Poás area) were used to determine neosporosis seroprevalence and the association of seropositivity with environmental and management factors. The farms involved ...
Effect of neosporosis on productive and reproductive performance of dairy cattle in Costa Rica
(Elsevier B.V, 2005-12)
A cross-sectional study was conducted to assess the effect of neosporosis on productive and reproductive parameters in dairy cows. Cows (n = 2743) from 94 farms located in the most important dairy areas in Costa Rica were ...
Economic values for production and functional traits in Holstein cattle of Costa Rica
(Elsevier Science B.V., 2001-08-20)
Economic values for production traits (carrier, fat, protein, and dressing percentage) and functional traits (conception rate,
survival rate, body weight, and rumen capacity) were calculated for Holstein cattle of Costa ...
Effect of a killed whole Neospora caninum tachyzoite vaccine on the crude abortion rate of Costa Rican dairy cows under field conditions
(Elsevier B.V, 2004-06-04)
A standard field trial was carried out to assess the effect of a commercial Neospora-vaccine based on
whole killed tachyzoites (Bovilis–Neoguard, Intervet1) on the abortion rate. Eight hundred and
seventy-six cows, over ...
Genetic comparison of breeding schemes based on semen importation and local breeding schemes: framework and application to Costa Rica
(American Dairy Science Association, 2004-05-01)
Local breeding schemes for Holstein cattle of Costa
Rica were compared with the current practice based
on continuous semen importation (SI) by deterministic
simulation. Comparison was made on the basis of ge-
netic ...
Modeling extended lactations of dairy cows
(American Dairy Science Association, 2000-06)
Nine mathematical models were compared for their
ability to predict daily milk yields (n = 294,986) in stan-
dard 305-d and extended lactations of dairy cows of
Costa Rica. Lactations were classified by parity ...