Browsing Artículos Científicos by Subject "DAIRY CATTLE"
Now showing items 1-12 of 12
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Analysis of test day yield data of Costa Rican dairy cattle
(Elsevier, 1998)Estimates of variance components for test day records in an animal model that considered multiple traits over multiple lactations were calculated using REML methodology. Test day records were classified into 11 periods ... -
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 ... -
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 ... -
Event-time analysis of reproductive traits of dairy heifers
(Elsevier, 1998-11)Data on the reproductive traits of dairy heifers were analyzed using event-time techniques. Traits analyzed were age at first calving (n = 4631), days to first breeding, and days open (n = 1992) during the first ... -
First report of bovine neosporosis in dairy cattle in Costa Rica
(British Veterinary Association, 1998-05-09)NEOSPOROSIS has recently been recognised as a major cause of abortion in dairy cattle worldwide (Barr and others 1990, Duff and Otter 1994, Boulton and others 1995). The disease is caused by the protozoan parasite, ... -
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 ... -
Herd management information systems to support cattle population research: The VAMPP® case
(Universidad de Costa Rica, 2020-04-01)Introduction. Livestock information systems, besides being indispensable for the daily management of the herd, can serve as a basis for research at the population level. Objective. The objective of the study was to analyze ... -
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 ... -
Prevalence of paratuberculosis (Mycobacterium avium subspecies paratuberculosis) in specialized dairy herds in Costa Rica
(Universidad Nacional, Costa Rica, 2015-09-30)A cross-sectional study was conducted in 194 specialized dairy herds in Costa Rica, to determine the prevalence of Mycobacterium avium subspecies paratuberculosis (MAP) in herds at a national level and by administrative ... -
Relación entre el estado serológico a leucosis bovina enzoótica y parámetros reproductivos en hatos lecheros especializados de Costa Rica
(Universidad Nacional, Costa Rica, 2015-03-04)Se realizó un estudio longitudinal y analítico para determinar la relación entre el estado serológico al virus de la leucosis bovina enzoótica (VLBE) y los parámetros reproductivos, en 26 fincas lecheras de Costa Rica ... -
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 ...