Abstract
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 2013. A total of 3,109 phenotypic records from 2,271 Landrace (L) and 838 Yorkshire sows (Y) were analyzed. Variance and covariance components, heritabilities and correlations were estimated using an Average Information Restricted Maximum Likelihood (AIREML) procedure. The 5-trait animal model contained the fixed effects of first farrowing year-season, breed group, and age at first farrowing. Random effects were sow and residual. Estimates of heritabilities were medium for all five traits (0.17±0.04 for LPL and LBA to 0.20±0.04 for LPW). Genetic correlations among these traits were high, positive, and favorable (p<0.05), ranging from 0.93±0.02 (LPL-LWW) to 0.99±0.02 (LPL-LPW). Sow genetic trends were non-significant for LPL and all lifetime production traits. Sire genetic trends were negative and significant for LPL (−2.54±0.65 d/yr; p = 0.0007), LBA (−0.12±0.04 piglets/yr; p = 0.0073), LPW (−0.14±0.04 piglets/yr; p = 0.0037), LBW (−0.13±0.06 kg/yr; p = 0.0487), and LWW (−0.69±0.31 kg/yr; p = 0.0365). Dam genetic trends were positive, small and significant for all traits (1.04±0.42 d/yr for LPL, p = 0.0217; 0.16±0.03 piglets/yr for LBA, p<0.0001; 0.12±0.03 piglets/yr for LPW, p = 0.0002; 0.29±0.04 kg/yr for LBW, p<0.0001 and 1.23±0.19 kg/yr for LWW, p<0.0001). Thus, the selection program in this commercial herd managed to improve both LPL and lifetime productive traits in sires and dams. It was ineffective to improve LPL and lifetime productive traits in sows.
Highlights
Length of productive life (LPL) and lifetime production traits are important for commercial swine operations because they affect efficiency of production, costs, and profitability
The objective of this research were to estimate genetic parameters and trends for LPL, LBA, LPW, LBW, and LWW using data from a commercial swine population composed of purebred Landrace and Yorkshire pigs kept in an open-house system under Thai tropical environmental conditions
The Least squares means (LSM) for first-farrowing year (FFY)-seasons ranged from 281.39±141.74 (2013-rainy) to 1,036.88±99.81 (1993-rainy) d for LPL, 27.40±10.11 (2013-rainy) to 70.34±8.56 (1996-rainy) piglets for LBA, 21.01±8.87 (2013-rainy) to 63.90±7.50 (1996-rainy) piglets for LPW, 43.77±13.44 (2001-summer) to 109.95±5.92 (2009-rainy) kg for LBW, and 159.71±66.92 (2013-rainy) to 469.67±25.01 (2009-rainy) kg for LWW
Summary
Length of productive life (LPL) and lifetime production traits (lifetime number of piglets born alive [LBA], lifetime number of piglets weaned [LPW], lifetime litter birth weight [LBW], and lifetime litter weaning weight [LWW]) are important for commercial swine operations because they affect efficiency of production, costs, and profitability. Sows that have long LPL would be more productive and profitable than sows with short LPL (Stalder et al, 2003; Abell, 2011). Increasing LPL is expected to increase the productivity of sows in the breeding herd as well as the profitability of swine operations. Swine producers in Thailand have focused their culling and selection on traits measured in individual parities (e.g., litter size at birth and weaning, individual piglet weight and litter weight at birth and at weaning) instead of LPL and lifetime production traits. The target of Thai commercial swine producers has been to produce more and heavier piglets to reduce production costs
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
