tailieunhanh - Báo cáo sinh học: " Longitudinal random effects models for genetic analysis of binary data with application to mastitis in dairy cattle"

Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học thế giới đề tài: Longitudinal random effects models for genetic analysis of binary data with application to mastitis in dairy cattle | 457 Genet Sei. Evol. 35 2003 457-468 INRA EDP Sciences 2003 DOI gse 2003034 Original article Longitudinal random effects models for genetic analysis of binary data with application to mastitis in dairy cattle Romdhane Rekayaa Daniel Gianolab Kent Weigelb George Shookb a Department of Animal and DairY Science University of Georgia Athens GA 30602 USA b Department of Dairy Science University of Wisconsin Madison WI 53706 USA Received 13 June 2002 accepted 13 March 2003 Abstract - a Bayesian analysis of longitudinal mastitis records obtained in the course of lactation was undertaken. Data were 3341 test-day binary records from 329 first lactation Holstein cows scored for mastitis at 14 and 30 days of lactation and every 30 days thereafter. First the conditional probability of a sequence for a given cow was the product of the probabilities at each test-day. The probability of infection at time t for a cow was a normal integral with its argument being a function of fixed and random effects and of time. Models for the latent normal variable included effects of 1 year-month of test a five-parameter linear regression function fixed within age-season of calving genetic value of the cow environmental effect peculiar to all records of the same cow residual. 2 As in 1 but with five parameter random genetic regressions for each cow. 3 A hierarchical structure where each of three parameters of the regression function for each cow followed a mixed effects linear model. Model 1 posterior mean of heritability was . Model 2 heritabilities were and at days 14 60 120 and 305 respectively. Model 3 heritabilities were and at days 14 60 120 and 305 respectively. Bayes factors were Model 1 Model 2 Model 1 Model 3 and Model 2 Model 3 . The probability of mastitis for an average cow using Model 2 was and at days 14 60 120 and 305 respectively. Relaxing the conditional independence assumption via an .

• Báo cáo khoa học
• Báo cáo sinh học hay
• cách trình bày báo cáo
• báo cáo sinh học
• công trình nghiên cứu sinh học
• tài liệu về sinh học