IGF-I, IGFBP-2 and -3 but not GH concentrations are different in normal and poor growing piglets

Supplementation with Fermented Feedstuff Enhances Orexin Expression and Secretion Associated with Increased Feed Intake and Weight Gain in Weaned Pigs

The health status of weaned pigs is crucial for their subsequent growth performance. Supplementation with fermented feedstuff is able to improve the feed intake and growth of weaned pigs; however, the exact mechanism behind this is not clear. Hence, in the present study a total of 320 Duroc × Landrace × Yorkshire weaned pigs were selected and allocated to the following two groups: unfermented diet group (UFD) and fermented diet group (FD). The experimental period lasted 21 days. At the end of the experiment, feces, blood, and gastrointestinal tissue samples (including the stomach, jejunum, and ileum) were collected and used for further analysis. The results of growth performance suggested that the FD group had significantly increased (p < 0.05) average daily feed intake (ADFI) and average daily gain (ADG) during the first week, during the last two weeks, and over the entire three-week period compared with the UFD group. The results of the apparent nutrient digestibility of pigs showed that, compared with the UFD group, the FD group showed increased phosphorus (p < 0.05) and CP (p < 0.1) digestibility. There were no significant differences in the serum biochemical parameters between the UFD and FD groups. Moreover, our results showed that the FD group showed significantly increased gene expression of SGLT1 and PepT1 in the jejunum (p < 0.05). Compared with the UFD group, the FD group showed an increased (p < 0.05) serum orexin level and prepro-orexin (PPOX) expression in the gastric fundus, jejunum, and ileum mucosa and increased IGF-1 and IGFR expression in the jejunum. Collectively, these results indicated that supplementation with fermented feedstuff in the diet effectively enhanced the feed intake and growth of weaned pigs and that this may have been caused by the increased orexin, IGF-1, and IGFR serum levels.

Differentiation Potential of Mesenchymal Stem/Stromal Cells Is Altered by Intrauterine Growth Restriction

Consistency in clinical outcomes is key to the success of therapeutic Mesenchymal Stem/Stromal cells (MSCs) in regenerative medicine. MSCs are used to treat both humans and companion animals (horses, dogs, and cats). The properties of MSC preparations can vary significantly with factors including tissue of origin, donor age or health status. We studied the effects of developmental programming associated with intrauterine growth restriction (IUGR) on MSC properties, particularly related to multipotency. IUGR results from inadequate uterine capacity and placental insufficiency of multifactorial origin. Both companion animals (horses, dogs, cats) and livestock (pigs, sheep, cattle) can be affected by IUGR resulting in decreased body size and other associated changes that can include, alterations in musculoskeletal development and composition, and increased adiposity. Therefore, we hypothesized that this dysregulation occurs at the level of MSCs, with the cells from IUGR animals being more prone to differentiate into adipocytes and less to other lineages such as chondrocytes and osteocytes compared to those obtained from normal animals. IUGR has consequences on health and performance in adult life and in the case of farm animals, on meat quality. In humans, IUGR is linked to increased risk of metabolic (type 2 diabetes) and other diseases (cardiovascular), later in life. Here, we studied porcine MSCs where IUGR occurs spontaneously, and shows features that recapitulate human IUGR. We compared the properties of adipose-derived MSCs from IUGR (IUGR-MSCs) and Normal (Normal-MSCs) new-born pig littermates. Both MSC types grew clonally and expressed typical MSC markers (CD105, CD90, CD44) at similar levels. Importantly, tri-lineage differentiation capacity was significantly altered by IUGR. IUGR-MSCs had higher adipogenic capacity than Normal-MSCs as evidenced by higher adipocyte content and expression of the adipogenic transcripts, PPARγ and FABP4 (P < 0.05). A similar trend was observed for fibrogenesis, where, upon differentiation, IUGR-MSCs expressed significantly higher levels of COL1A1 (P < 0.03) than Normal-MSCs. In contrast, chondrogenic and osteogenic potential were decreased in IUGR-MSCs as shown by a smaller chondrocyte pellet and osteocyte staining, and lower expression of SOX9 (P < 0.05) and RUNX2 (P < 0.02), respectively. In conclusion, the regenerative potential of MSCs appears to be determined prenatally in IUGR and this should be taken into account when selecting cell donors in regenerative therapy programmes both in humans and companion animals.

Effect of Dietary Inulin Supplementation on Growth Performance, Carcass Traits, and Meat Quality in Growing-Finishing Pigs

Inulin is one of the commercially feasible dietary fibers that has been implicated in regulating the gut health and metabolism of animals. This experiment was conducted to investigate the effect of dietary inulin supplementation on growth performance and meat quality in growing-finishing pigs. Thirty-six Duroc × Landrace × Yorkshire White growing barrows (22.0 ± 1.0 kg) were randomly allocated to two dietary treatments consisting of a basal control diet (CON) or basal diet supplemented with 0.5% inulin (INU). Results showed that inulin supplementation tended to increase the average daily gain (ADG) at the fattening stage (0.05 < p < 0.10). Inulin significantly increased the dressing percentage (p < 0.05) and tended to increase the loin-eye area. The serum concentrations of insulin and IGF-I were significantly higher (p < 0.05) in the INU group than in the CON group. Moreover, inulin supplementation significantly elevated the expression level of myosin heavy chain II b (MyHC IIb) in the longissimus dorsi (p < 0.05). Inulin significantly upregulated the expression of mammalian rapamycin target protein (mTOR) but decreased (p < 0.05) the expression level of muscle-specific ubiquitin ligase MuRF-1. These results show the beneficial effect of inulin supplementation on the growth performance and carcass traits in growing-finishing pigs, and will also facilitate the application of inulin in swine production.

Identifying factors contributing to slow growth in pigs

Pigs that grow slower than their contemporaries can cause complications for animal welfare and profitability. This study was conducted to investigate factors that may contribute to slow growth of pigs. Pigs ( = 440) farrowed by 65 sows were monitored from birth to market. Pigs were categorized as slow, average, and fast growers based on market weight adjusted to 170 d of age (slow growers were <105 kg, average growers were between 105 and 125 kg, and fast growers were >125 kg). Blood samples were collected from 48 focal pigs at 9 and 21 wk of age and analyzed for hormone and free AA concentrations. Data were analyzed using the Mixed and Logistic procedures of SAS. Slow-growing pigs accounted for 10% of pigs marketed, average growers accounted for 49% of pigs marketed, and fast growers accounted for 41% of pigs marketed. Compared with fast growers, slow growers were lighter at birth ( < 0.01), at weaning ( < 0.01), and at nursery exit ( < 0.01) and had less backfat ( < 0.01) and smaller loin muscle area ( < 0.01) at marketing at 21 wk of age. Slow growers had lower plasma concentrations of IGF-1 ( = 0.03) and insulin ( < 0.001) during the nursery period and lower concentrations of leptin ( < 0.001) and insulin ( < 0.001) during the finishing period compared with average and fast growers. Serum concentrations of several essential, nonessential, and total free AA were less for slow growers during both the nursery and finishing periods compared with average and fast growers. Gilts were more likely to become slow growers than barrows (odds ratio = 2.17, 95% confidence interval = 1.19 to 3.96, = 0.01). Litter size and parity of the pigs' dam were not associated with slow growth. These results suggest that low concentrations of IGF-1, insulin, leptin, and AA may contribute to or be associated with slow growth in pigs.

Effect of oral supplementation with different energy boosters in newborn piglets on pre-weaning mortality, growth and serological levels of IGF-I and IgG

Oral supplements are commonly used in commercial herds to improve energy status and passive immune acquisition of newborn piglets. However, there is little scientific evidence on the efficacy of oral supplements for piglets. The objective of this experiment was to study the effects of 2 oral supplementation products on piglet pre-weaning mortality and growth. A total of 62 litters (749 piglets) were distributed according to the sow's parity among 3 treatments: 1) CONTROL group, no oral supplementation to piglets; 2) EN group, light piglets (LP: birth BW ≤ 1.35 kg) received 2 doses of 1 mL Lianol Colostro; 3) COLO group, LP received 2 doses of 5 mL ColoBoost. Treatments were administered within 4 h after birth and repeated 8 h after the first dose. Piglets were weighed at d 0, 1, 10, and 21 after birth. Piglet rectal temperature was recorded shortly after birth and at 24 h. Cross-fostering was performed 24 h after birth. Blood samples were obtained from 39 LP at d 5 and 21 to determine IGF-I and IgG levels. Total mortality and LP mortality rate (percentage of LP in the litter that died) were recorded. At d 1, the EN group had a lower total mortality rate (2.1 vs. 7.1 ± 1.4%, = 0.036) and LP mortality rate (4.5 vs. 11.1 ± 2.8%, = 0.047) than the CONTROL group. At d 1, the COLO group tended to have a lower LP mortality rate than the CONTROL group (8.4 vs. 11.1 ± 3.0%, = 0.058). After cross-fostering, the COLO group had a lower LP mortality rate at d 21 than the CONTROL group (6.3 vs. 18.3 ± 2.8%, = 0.043). The total mortality rate and piglet body weight did not differ among groups at d 21. Piglets in the COLO group had a higher IgG level at d 5 than those in the EN group (24.9 vs. 16.3 ± 2.15 mg/mL, = 0.034) and tended to be higher than those in the CONTROL group (24.9 vs. 17.7 ± 2.35 mg/mL, = 0.072). Piglets in the EN group had a higher serum IGF-I concentration than those in the CONTROL group at d 21 (137.6 vs. 100.3 ± 11.15 ng/mL, = 0.030). The results suggested that 2 doses of oral supplementation within 12 h after birth might be effective in increasing small piglet survival and improving their IGF-I or IgG levels during lactation without compromising litter growth.

Impact of nutritional programming on the growth, health, and sexual development of bull calves

The growth, health, and reproductive performance of bull calves are important prerequisites for a successful cattle breeding program. Therefore, several attempts have been made to improve these parameters via nutritional programming. Although an increase in energy uptake during the postweaning period (7-8 mo of age) of the calves leads to a faster growing rate, it has no positive effects on sexual development. In contrast, a high-nutrition diet during the prepubertal period (8-20 wk of age) reduced the age at puberty of the bulls and increased the size and/or weight of the testis and the epididymal sperm reserves. This faster sexual development is associated with an increased transient LH peak, which seems to be mediated by an increase in serum IGF-I concentrations. However, the exact mechanisms responsible for the interaction between nutrition and the subsequent development of the calves are not clear. The sexual development of bull calves depends not only on the nutrition of the calves after birth but also on the feed intake of their mothers during pregnancy. In contrast to the effects of the feed intake of the bull calves, a high-nutrition diet fed to the mother during the first trimester has negative effects on the reproductive performance of their offspring. In conclusion, it has been clearly demonstrated that growth, health, and reproductive performance can be improved by nutritional programming, but further studies are necessary to obtain a better understanding about the mechanisms responsible for this phenomenon.

Expression of the insulin-like growth factor system in skeletal muscle during embryonic and postnatal development in the first filial generation pigs from Erhualian and Yorkshire reciprocal crosses

In this study, we detected the expression of IGF-I, IGF-II, IGF-IR, IGF-IIR, and IGFBP-3 mRNA at 50 (E50), 70 (E70), and 90 (E90) days of gestation, and 1 (D1), 20 (D20), 70 (D70), 120 (D120), and 180 (D180) days of age in the longissimus dorsi (LD) and the semitendinosus (ST) of pigs from a Yorkshire boar×Erhualian sow (YE) cross as well as a Erhualian boar×Yorkshire sow (EY) cross. We found that the expression of IGF-I and IGF-II mRNA in skeletal muscle tissues differed based on developmental age and reciprocal cross type (P<0.05). The expression of IGF-I mRNA exhibited a fluctuant ascending trend. In contrast, IGF-II showed a fluctuant descending trend after birth. The levels of IGF-IR mRNA were higher before birth compared with after birth except for the ST of EY pigs at D120 (P<0.05). The expression of IGF-IIR and IGFBP-3 mRNA remarkably changed with age and reciprocal cross type (P<0.05). IGF-I, IGF-II, and IGFBP-3 mRNA were positively correlated with IGF-IR from 50E to 180D. These data suggest that the expression of IGF-system genes exhibits specific developmental patterns in the skeletal muscle tissues of pigs from reciprocal crosses at different developmental stages and may show linked expression during certain periods of development. Our results may provide a valuable resource for the molecular breeding of pigs.

Infection, immunity and the neuroendocrine response

The Central Nervous (CNS) and Immune Systems (IS) are the two major adaptive systems which respond rapidly to numerous challenges that are able to compromise health. The defensive response strictly linking innate to acquired immunity, works continuously to limit pathogen invasion and damage. The efficiency of the innate response is crucial for survival and for an optimum priming of acquired immunity. During infection, the immune response is modulated by an integrated neuro-immune network which potentiates innate immunity, controls potential harmful effects and also addresses metabolic and nutritional modifications supporting immune function. In the last decade much knowledge has been gained on the molecular signals that orchestrate this integrated adaptive response, with focus on the systemic mediators which have a crucial role in driving and controlling an efficient protective response. These mediators are also able to signal alterations and control pathway dysfunctions which may be involved in the persistence and/or overexpression of inflammation that may lead to tissue damage and to a negative metabolic impact, causing retarded growth. This review aims to describe some important signalling pathways which drive bidirectional communication between the Immune and Nervous Systems during infection. Particular emphasis is placed on pro-inflammatory cytokines, immunomodulator hormones such as Glucocorticoids (GCs), Growth hormone (GH), Insulin-like Growth Factor-1 (IGF-1), and Leptin, as well as nutritional factors such as Zinc (Zn). Finally, the review includes up-to-date information on this neuroimmune cross-talk in domestic animals. Data in domestic animal species are still limited, but there are several exciting areas of research, like the potential interaction pathways between mediators (i.e. cytokine-HPA regulation, IL-6-GCS-Zn, cytokines-GH/IGF-1, IL-6-GH-Leptin and thymus activity) that are or could be promising topics of future research in veterinary medicine.

A rapid surface plasmon resonance (SPR) biosensor immunoassay for screening of somatotropins in injection preparations

The use of growth hormones (recombinant somatotropins (rSTs)) is approved in several countries, e.g. the USA, Brazil and Australia to enhance growth or lactating performances of livestock. Their use in the EU is banned, however, due to the widespread application, the illegal use within the EU cannot be excluded. To screen for rSTs in injection preparations, a biosensor immunoassay (BIA) using surface plasmon resonance (SPR) technology was developed. Compared to existing analysis methods for rSTs, like radio immunoassay (RIA) and enzyme-linked immunosorbent assay (ELISA), this technique provides a rapid (7 min) alternative. A direct BIA was compared to an indirect (inhibition) BIA and the performances of several antibodies against (r)STs were compared in the indirect BIA. In the final inhibition assay, using rabbit anti-bovine rST, extracts from several injection preparations were shown to contain bovine rST (rbST). The limit of detection for rbST in the assay is 0.008 microg mL(-1) which is far below the expected concentrations in injection preparations. Although the cross-reactivities for STs of other species were low, screening of injection preparations for porcine, equine and human ST was feasible through the analysis of less diluted extracts. Tryptic digestion followed by nano-electrospray liquid chromatography-ion trap tandem mass spectrometry (nano-LC-MS/MS) was used to identify STs.

Changes in circulating insulin-like growth factor-I, insulin-like growth factor binding proteins, and leptin in weaned pigs infected with Salmonella enterica serovar Typhimurium

One of the hallmarks of the pathophysiology of enteric disease in young pigs is reduced growth performance. This reduction in growth is associated with changes in the endocrine somatotropic growth axis. Our laboratory previously demonstrated that circulating insulin-like growth factor-I (IGF-I) was reduced in pigs infected with Salmonella enterica serovar Typhimurium (S. typhimurium) while circulating growth hormone remained unchanged. The objective of the current study was to determine if infection with S. typhimurium also was associated with changes in circulating IGF binding proteins (IGFBP). In addition, pigs experiencing active enteric disease have reduced feed intake. Because this inappetence may be related to systemic appetite reduction signals, we also evaluated circulating leptin in pigs undergoing active S. typhimurium-induced enteric disease. Crossbred pigs were penned in environmentally controlled rooms with free access to feed and water. Following an acclimation period, pigs were gavaged with 10(10) cfu of S. typhimurium (SAL; n=6) or were given a similar volume of sterile growth media (CON; n=6). Rectal temperatures and feed intakes were measured daily through 168 h to track the time course of the response to S. typhimurium infection. Samples of serum were obtained by jugular venipuncture at 0, 24, 48, 96 and 168 h after infection. Sera were frozen until evaluation for IGF-I by immunoradiometric assay (IRMA). In addition, sera were subjected to western ligand blotting utilizing 125I-IGF-I and 125I-IGF-II. Images were evaluated for total IGFBP and IGFBP-3 by densitometric analyses. Rectal temperature was increased in SAL pigs 24h post-infection (P<0.001) but not at other times. Feed intake was reduced in SAL pigs during the intervals 24-72 h (P<0.001) and 96-144 h (P<0.05) after infection. Serum IGF-I, expressed as a percentage of the 0 h concentration, was reduced in SAL pigs versus CON pigs at 48 h (28.1+/-18.7% versus 102.2+/-17.1%; P<0.01) and 96 h (20.0+/-18.7% versus 128.4+/-17.0%; P<0.0001) post-infection. Both total IGFBP and IGFBP-3, as estimated by ligand blotting, also were reduced in infected pigs at 48 h postchallenge (P<0.05). IGFBPs were similar between the two treatments at other sampling times. Concentrations of IGFBP-3 also were estimated utilizing an IRMA for human IGFBP-3. Serum IGFBP-3 was reduced in S. typhimurium-infected pigs at 24 h (P<0.01), 48 h (P<0.001), 96 h (P<0.001), and 168 h (P<0.05). Serum leptin levels were similar between SAL and CON pigs. The data suggest that swine enteric disease is associated with reduced circulating IGF-I and reductions in total IGFBP and IGFBP-3. However, serum leptin was not affected by enteric disease challenge.