Developmental factors that influence sow longevity1

Abstract

The length of adult sow life is now recognized as both an economic and a welfare concern. However, there are no consistent definitions to measure sow longevity. This study assessed 6 different descriptions of longevity and determined their relationship with developmental performance factors. Longevity definitions included stayability (probability of a sow producing 40 pigs or probability of her reaching 4 parities), lifespan (number of parities a female has accumulated before culling), lifetime prolificacy (number of pigs born alive during the productive lifetime of a female), herd life (time from first farrowing to culling), and pigs produced per day of life. Data consisted of 14,262 records of Yorkshire females from both nucleus and multiplication herds across 21 farms from 4 seedstock systems. Within a subset of the data, information was available on the litter birth record of the female and her growth and composition data. Therefore, data were subdivided into 2 data sets, consisting of 1) data A, data from the farrowing records of a female, and 2) data B, data A and information from the litter birth record of a female and the growth and backfat data from a female. A Cox proportional hazards model was used to determine the relationship of developmental factors and first farrowing record with longevity. Those factors that were significantly (P < 0.0001) associated with longevity, regardless of definition, were age at first farrowing, litter size at first farrowing and last farrowing, number of stillborn in the first litter, adjusted 21-d litter weight of the first litter, herd type, backfat, and growth. Within a contemporary group, fatter, slower growing gilts had a decreased risk of being culled. Additionally, sows that had more pigs born alive, fewer stillborn pigs, and heavier litters at 21 d of lactation in their first litter had a decreased risk of being culled. Furthermore, sows from nucleus herds experienced a greater risk of being culled. Many factors affected longevity, regardless of definition. Pork producers can implement management protocols that can extend the productive life of breeding females, resulting in improved profitability and animal welfare.

Lifetime and per year productivity of sows in four pig farms in the tropics of Mexico

“…However, they are higher than values (34.9 and 38.5 piglets) reported in the USA by Hoge and Bates (2011) and Nikkilä et al (2013)). The means for LKF, in this study, are lower than those found in Thailand by Noppibool et al (2013) in Landrace (89.8 kg) and Yorkshire sows (88.2 kg).…”

“…However, some studies report the lack of significant effect of age at first farrowing on lifetime productivity (López and Galíndez 2011a, b;Noppibool et al 2013). Furthermore, there are some reports on the effect of litter size at first farrowing on lifetime productivity at farrowing and at weaning (Hoge and Bates 2011;Sobczynska et al 2013). Lifetime productivity estimates and factors affecting them, under the conditions of Mexico and particularly of the Mexican tropics, have not been reported, except of a study on the length of productive life of sows in the herd (Segura-Correa et al 2011a).…”

Genetic associations for gilt growth, compositional, and structural soundness traits with sow longevity and lifetime reproductive performance1

“…Fast growth rate increased culling risk in previously published work involving Yorkshire sows (Yazdi et al, 2000a;Hoge and Bates, 2011), but such effect was not observed in Swedish Landrace (Yazdi et al, 2000b). Knauer et al (2010) reported negative regression coeffi cients for stayability on ADG in crossbred maternal lines.…”

“…Along these assumptions, as maternal line females, gilts from the current population may have had suffi cient backfat and therefore antagonistic associations remained weak in the quantitative analyses. Yazdi et al (2000a) and Hoge and Bates (2011) reported that Yorkshire females with greater backfat thickness experienced a decreased culling risk, but according to Yazdi et al (2000b) side-fat thickness was not associated with risk of culling in Swedish Landrace sows. Fernàndez de Sevilla et al (2008) found low backfat thickness increasing risk of culling in Spanish Landrace but not in Large White sows.…”

“…Instead, Stalder et al (2005) reported an unfavorable association between DAYS and lifetime number of piglets weaned. Hoge and Bates (2011) reported antagonistic association between DAYS and LBA in United States Yorkshire. Tummaruk et al (2001) reported a favorable association between growth rate up to 100 kg BW and litter size in parities 1 to 5 in Swedish Landrace and Yorkshire nucleus sows.…”