Genetic correlations between lactation performance and growing-finishing traits in pigs

Abstract

Genetic selection for increased litter size of sows increases the risk of a large negative energy balance during lactation. Furthermore, the feed intake capacity of the lactating sows might be reduced due to the simultaneous selection for greater feed efficiency during the growth phase when sows were actually reared as finishers but later on selected for breeding. There is a need to improve lactation performance of sows and continue selection for feed efficiency of grower-finishers in commercial breeding. Therefore, this study was conducted to estimate genetic correlations between growing-finishing traits and lactation performance traits. An additional objective was to study the impact of including additive social effects in the animal model on genetic correlation estimates. Analyses were performed on a population of 1,149 commercial crossbred sows with repeated observations on lactation performance traits and their 7,723 grower-finisher offspring. The genetic correlation between daily BW gain of grower-finishers and starting BW of lactating sows was positive (rg = 0.24; P < 0.05). The correlation between off-test backfat of grower-finishers and fat mass of lactating sows was also positive (rg = 0.53; P < 0.05). The genetic regulation of feed intake from the beginning of lactation seems to differ from the genetic regulation of feed intake during the growing-finishing period, as the correlation between these 2 traits was low (rg = +0.23; P < 0.05). Feed efficiency during growing-finishing and lactation phases showed similar tendencies as the genetic correlation between residual feed intake of the grower-finisher and lactation efficiency of sows was -0.51 (P < 0.05). Taking heritable social effects into account for daily BW gain and feed intake did not affect the genetic correlation estimates, either within growing-finishing traits or between growing-finishing traits and lactation performance traits. It was concluded that in the absence of antagonistic genetic correlations, selection for growing-finishing traits in dam lines could be combined with selection for lactation performance traits.

Genetic parameters for feed intake, litter weight, body condition and rebreeding success in primiparous Norwegian Landrace sows

“…The genetic correlation between FEED and LW was also positive but imprecise (r g = 0.33, PSD = 0.20). Bergsma et al (2008) and Bergsma et al (2013) estimated similar genetic correlations between feed intake during lactation and litter weight gain (0.48 and 0.58). Sows with good appetite have a genetic potential for producing heavy litters.…”

“…The estimated heritabilities for appetite during the first 3 weeks (APP; h 2 = 0.07, PSD = 0.03) and for feed intake at 3 weeks (FEED; h 2 = 0.06, PSD = 0.03) were, however, lower than estimates previously presented in the literature. Bergsma et al (2008) estimated the heritability for voluntary feed intake during the whole lactation period at 0.30, Gilbert et al (2012) at 0.26 and Bergsma et al (2013) at 0.23. Bunter et al (2010) reported a heritability of average lactation feed intake at 0.15, and Hermesch et al (2010) estimated the heritability at 0.10 during early lactation (5 to 14 days).…”

“…Hermesch et al (2010) used data from several parities and reported similar estimates for sow weight (0.26) and back fat (0.40) at weaning. Bergsma et al (2008) estimated the heritability for BW loss during lactation at 0.20 and Bergsma et al (2013) at 0.14. Inspired by the discussion by ten Napel et al (1995) concerning normal (⩽7 days) and prolonged intervals, both WSI7 and WSI50 as well as delayed service (DELAYED) were studied.…”

Impact of feed restriction on the performance of highly prolific lactating sows and its effect on the subsequent lactation

“…The results of the present study confirm the observations of Vinsky et al (2006) and Patterson et al (2011) that hyper-prolific sows, despite experimentally restricted-fed to 50% of the expected voluntary intake and extensive body tissue catabolism, presented estrus almost immediately after weaning and acceptable farrowing rates after breeding. This may be partially due to the genetic selection against weaning-to-estrus interval (Vinsky et al, 2006;Bergsma et al, 2013). However, although energy balance may become positive after weaning, sows with rapid return to estrus may not have fully recovered from the damages caused by catabolism during lactation, with possible negative impacts on follicle and embryo quality, and consequently on the size and quality of the next litter (Quesnel et al, 2007;Quesnel, 2009).…”

The quantitative genetics of indirect genetic effects: a selective review of modelling issues

“…A farm may, for example, consist of units of 8-12 groups each, which introduces the risk of confounding environmental unit or unit  batch effects with IGEs, even when random group effects are included in the statistical model. Compared with a previous study (Bergsma et al, 2008), Bergsma et al (2013), for example, found substantially smaller IGEs in growth rate in domestic pigs due to an increase in the data set and a change in the statistical model.…”