Causal Relationships Between Milk Yield, Body Condition Score and Fertility in Italian Holstein Friesian Dairy Cattle

Tuesday, August 19, 2014: 5:30 PM
Bayshore Grand Ballroom D (The Westin Bayshore)
Mara Battagin , Italian Holstein Friesian Cattle Breeders Association, Cremona, Italy
Francesco Tiezzi , North Carolina State University, Raleigh, NC
Martino Cassandro , Department of Agronomy, Food, Natural resources, Animals and Environment, University of Padova, Legnaro, Italy
Christian Maltecca , North Carolina State University, Raleigh, NC
Abstract Text:

The aim of the study was to explore genetic relationship among milk yield, body condition score (BCS) and pregnancy status (PR) in Italian Holstein cows using a recursive effects model. Two recursive models and a multiple-trait model were compared in four different subsets of data. The antagonistic effect of milk yield on BCS and PR was confirmed, as well as the positive relationship between BCS and PR. Recursive effects of BCS on PR was moderate, the strongest occurred between 80-110 DIM, and consist in 0.85% of probability for a cow to be pregnant for an extra point of BCS (i.e. form 2.5 to 3.5). The direct causal effect of MY on BCS was weak and increased during lactation, reaching -0.10 point of BCS for additional 10kg/d of milk (170-201 DIM).


Body Condition Score

Milk yield


Structural equation model