The objective of this research was to estimate genetic parameters and trends for length of productive life (LPL), lifetime number of piglets born alive (LBA), lifetime number of piglets weaned (LPW), lifetime litter birth weight (LBW), and lifetime litter weaning weight (LWW) in a commercial swine farm in Northern Thailand. Data were gathered during a 24-year period from July 1989 to August 201...

The objectives of this study were to determine the selection potential (genetic variation) of sow efficiency traits (prolificacy, longevity), to understand the co-responses (genetic correlations) among sow efficiency traits and other economically important traits (performance, carcass quality, and meat quality), and determine the feasibility of developing breeding value estimates for sow effici...

OBJECTIVE This study estimated the genetic parameters for productive and reproductive traits. METHODS The data included production and reproduction records of animals that have calved between 1979 and 2013. The genetic parameters were estimated using multivariate mixed models (DMU) package, fitting univariate and multivariate mixed models with average information restricted maximum likelihood...

Theoretical and empirical studies of life history aim to account for resource allocation to the different components of fitness: survival, growth, and reproduction. The pioneering evolutionary ecologist David Lack [(1968) Ecological Adaptations for Breeding in Birds (Methuen and Co., London)] suggested that reproductive output in birds reflects adaptation to environmental factors such as availa...

A study of genetic variation and interrelationship among grain yield and its component traits in rice (Oryza sativa L.) was carried out using 64 exotic rice genotypes. Maximum genotypic and phenotypic variance was exhibited by number of spikelets per panicle followed by plant height and days to maturity. The maximum GCV and PCV was exhibited by number of spikelets per panicle followed by number...

The objective of the present study was to estimate (co)variance components for length of productive life (LPL) and some alternative reproductive traits of 6-year-old Nellore cattle. The data set contained 57,410 records for age at first calving from Nellore females and was edited to remove animal records with uncertain paternity and cows with just one piece of calving information. Only animals ...