Excessive backfat of sows at 109 d of gestation induces lipotoxic placental environment and is associated with declining reproductive performance1

Abstract

This study investigated the influence of sow backfat thickness at 109 d of gestation on sow and piglet performance. Data from 846 farrowing multiparous Yorkshire sows with parity from 3 to 5 were collected from a pig breeding farm. Sows were divided into six groups based on backfat thickness (≤16, 17-18, 19-20, 21-22, 23-24, and ≥25 mm) at 109 d of gestation. The evaluation of reproductive performance included the litter size, litter weight at birth and at weaning of 21 d, weight of placenta at parturition, placental efficiency, and sow daily feed intake of lactation. Parameters related to plasma lipids and the placental-lipid concentration were measured. Data were analyzed to determine the relationships among backfat thickness, placental lipids, and piglet performance. No differences were observed in the number of piglets born, born alive, after cross-foster, and at weaning among groups (P > 0.05). The litter weight at birth and weaning, piglet birth weight, weaning weight, placental efficiency, and the number and percentage of piglets born with weight of <800 g showed a significantly quadratic effect of the backfat thickness (P < 0.05). During lactation, sow daily feed intake linearly decreased with increased backfat thickness at 109 d of gestation (P < 0.05). Although triglycerides and low-density lipoprotein cholesterol (LDL-C) showed no significant difference, cholesterol and high-density lipoprotein cholesterol (HDL-C) and free fatty acid (FFA) concentrations significantly increased (P < 0.05) in both maternal and umbilical cord blood with increased backfat thickness of sow. Placental-lipid concentrations also significantly increased (P < 0.05) with increased backfat thickness. Moreover, backfat thickness and placental-lipid concentration were positively correlated with the number of piglets weighing <800 g (P < 0.01) but negatively correlated with birth weight, litter birth weight, and piglet weaned weight (P < 0.01). In conclusion, backfat thickness of sow at end of gestation correlates with birth and weaning weight of piglets. Placental ectopic lipid accumulation-induced lipotoxicity is likely responsible for such correlation.

Obesity of Sows at Late Pregnancy Aggravates Metabolic Disorder of Perinatal Sows and Affects Performance and Intestinal Health of Piglets

“…In the current study, our results showed that the excessive backfat thickness (≥21 mm) of Landrance × Large White sows at day 109 of gestation decreased the total number and litter weight of piglets born alive. Similar to the results of this study, Zhou et al [5] observed that increased backfat thickness of Large White sows at day 109 of gestation had a convex quadratic relationship with litter weight of piglets born alive. Torres-Rovira et al [25] showed that the proportion of low birth weight in excessive backfat thickness sows was more than 20%.…”

“…Additionally, Catalano et al [26] reported that obesity in pregnant women during later pregnancy also increased the incidence of stillbirth and neonatal death. Some studies have shown that the placental dysfunction may be a determinant of maternal obesity during pregnancy leading to abnormal fetal development [5,27,28]. In our previous study, we found that when sows had a backfat ≥ 21 mm at days 109 of gestation, the higher m 6 A modification shown in genes associated with placental development limits the development of placental vasculature, thereby increasing the incidence of low birth weight in piglets [6].…”

“…The backfat thickness is a common indicator of sow body condition [2]. Increasing evidence shows that excessive backfat of sows during late gestation is closely related to reproductive disorders, including less litter size, lower litter weight gain, and more proportion of intrauterine growth restriction [3][4][5]. The latest research indicates that when Landrance × Large White sows have a backfat ≥ 21 mm at days 109 of gestation, the higher m6A modification shown in genes related to placental development may limit development of placental vasculature, thereby increasing the incidence of low birth weight in piglets [6].…”

Impaired Mitochondrial Function Results from Oxidative Stress in the Full-Term Placenta of Sows with Excessive Back-Fat

“…Thus, mitochondrial dysfunction and over generation of superoxide could be part of a vicious cycle and can be considered as a potential mechanism of placental dysfunction involved in obese pregnancy. Although several studies reveal that excessive back-fat of sows is associated with placental dysfunction [4,16], it is not currently known whether increased back-fat is coupled with changes in mitochondrial structure and function in the pig placenta.…”

Effects of dietary lysine levels on production performance, milk composition and plasma metabolites of the high-producing lactating sows

“…The modern sow has been selected for large litter size and milk production. In addition, balanced nutrition, more standardized management and effective disease control were widely used in sow production [1,2]. E ciency of reproduction signi cantly increased in the breeding herd [3].…”