Abstract
The factors that cause post-natal growth retardation (PGR) in pigs are complicated; however, metabolic and immune system impairment seem to be involved. The purpose of this study was to investigate the changes of blood parameters, hormone profiles, antioxidant capacity, and immune responses in PGR pigs. Blood and small intestinal mucosa samples were collected from 42-days-old PGR and healthy pigs. The results showed that compared with the healthy group, the relative weight of spleen and kidney were greater, but the liver was lighter in PGR pigs (P < 0.05). The PGR pigs had increased serum alanine transaminase, urea nitrogen, blood ammonia, IgG, and complement 4, but decreased glucose and albumin (P < 0.05). The higher levels of serum leptin (LEP) and thyroxin (T4), and the lower levels of insulin-like growth factor-1 (IGF-1), 5-hydroxytryptamine (5-HT), somatostatin (SS), and agouti gene-related protein (AgRP) were observed in PGR pigs (P < 0.05). Consistent with the serum levels of hormones, the mRNA levels of gut hormones and their receptors were also altered in intestinal mucosa from PGR pigs (P < 0.05). The PGR pigs exhibited higher plasma concentrations of interleukin-1β (IL-1β), IL-6, IL-8, and transformed growth factor beta (TGFβ) (P < 0.05). However, the mRNA expressions of several cytokines were lower in the small intestinal mucosa of PGR pigs (P < 0.05). Abnormal antioxidant indexes in serum of PGR pigs were observed, which was in accordance with the reduced mRNA expression of several anti-oxidative genes in the small intestinal mucosa of PGR pigs (P < 0.05). These data demonstrate that an abnormal gut hormone system, immune dysfunction, and decreased antioxidant capacity may contribute to PGR in pigs. These changes could provide a valuable target in the regulation of post-natal growth retardation in animals and humans.
Highlights
Post-natal growth retardation (PGR) piglet refers to a piglet that has failed to achieve its genetically determined growth potential [1]
An increase in serum concentrations of alanine transaminase, blood urea nitrogen, and blood ammonia but a decrease in albumin, alkaline phosphatase, and glucose were observed in PGR pigs (P < 0.05)
The changes of relative weights of the liver, spleen, and kidney in PGR pigs were consistent with reports that the relative weight of the liver was decreased and kidney was increased in the intrauterine growth restriction (IUGR) lamb, and that of the spleen was increased in low birth weight piglets [2, 28]
Summary
Post-natal growth retardation (PGR) piglet refers to a piglet that has failed to achieve its genetically determined growth potential [1]. It is important to seek the possible intervening targets to enhance growth in poorly performing piglets, ensuring a good growth rate post-weaning [9, 10]. Blood profiles, such as acute-phase proteins, have been used to assess the herd health, immune status, and growth potential in pigs [11, 12]. The levels of multiple hormones, such as growth hormone (GH), thyroxin (T4), and leptin (LEP) were altered in IUGR children and piglets [14, 15]. These anabolic hormones play important roles in many biological activities including cell survival, organ maturation, anti-inflammatory, and antioxidant [16, 17]. The increased serum levels of proinflammatory cytokines, such as interleukin-8 (IL-8) reflects the severe inflammatory response in pigs [21, 22]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
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 callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
