Department of Animal Science, Michigan State University, East Lansing 48824, USA.
J Anim Sci. 2011 Apr;89(4):1238-45. doi: 10.2527/jas.2010-3175. Epub 2010 Dec 23.
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.
母猪的寿命不仅是一个经济问题，也是一个福利问题。然而，目前还没有统一的定义来衡量母猪的寿命。本研究评估了 6 种不同的寿命定义，并确定了它们与发育性能因素的关系。寿命定义包括母猪的可繁殖力（生产 40 头仔猪的概率或达到 4 胎的概率）、寿命（母猪被淘汰前积累的胎次）、终生生产力（母猪繁殖期间活产仔猪的数量）、群体寿命（从第一次产仔到淘汰的时间）和每天生产的仔猪数。数据来自约克夏母猪的 14262 个记录，来自 4 个种猪系统的 21 个农场的核心群和扩繁群。在数据的一个子集，有关于母猪的产仔记录及其生长和组成数据的信息。因此，数据分为 2 个数据集，包括 1）数据集 A，母猪产仔记录的数据；2）数据集 B，数据集 A 以及母猪产仔记录的信息和母猪的生长及背膘数据。使用 Cox 比例风险模型来确定发育因素和第一胎产仔记录与寿命的关系。无论定义如何，与寿命显著相关的因素（P<0.0001）是首次产仔的年龄、首次产仔和最后一次产仔的窝产仔数、第一窝死产数、第一窝 21 日龄调整的窝重、群体类型、背膘和生长。在当代群体中，更胖、生长速度较慢的后备母猪被淘汰的风险较低。此外，第一窝产仔时活产仔数较多、死产仔数较少、21 日龄窝重较重的母猪被淘汰的风险较低。此外，来自核心群的母猪被淘汰的风险更大。许多因素影响着母猪的寿命，无论定义如何。猪肉生产者可以实施管理方案，延长繁殖母猪的生产寿命，从而提高盈利能力和动物福利。
