Aims
This study was conducted to assess the effects of acute heat stress (HS) on intestinal microbiota, and the associations with the changes in feed intake (FI) and serum profile.
Methods and ...Results
Twenty four individually housed pigs (Duroc × Large White × Landrace, 30 ± 1 kg body weight) were randomly assigned to receive one of three treatments (8 pigs/treatment): (i) thermal neutral (TN) conditions (25 ± 1°C), (ii) HS conditions (35 ± 1°C), (iii) pair‐feeding (PF) with HS under TN conditions. After 24‐h treatment, pigs were monitored to assess FI, and samples of serum and faeces were collected to investigate serum profile, microbial composition and short chain fatty acids (SCFAs). The results showed that HS decreased (P < 0·05) FI compared with the TN group. Compared with TN group, HS changed the serum profile by affecting biochemical parameters and hormones related with energy metabolism and stress response; immune indicators were also altered in HS group. Most of changes in serum profile were independent of FI reduction. Additionally, HS shifted the diversity and composition of faecal microbial community by increasing (P < 0·05) Proteobacteria and decreasing (P < 0·05) Bacteroidetes. Moreover, HS decreased (P < 0·05) the concentrations of propionate, butyrate, valerate, iso‐valerate and total SCFAs in faeces in an FI‐independent manner. Furthermore, the Spearman correlation analysis implied that changes of serum profile have potential correlation with alterations of faecal microbiota and their SCFAs metabolites in acute HS‐treated grow‐finishing pigs.
Conclusions
Metabolism disorders caused by 24‐h acute HS associated with changes of faecal microbiota and their SCFAs metabolites in an FI‐independent manner in grow‐finishing pigs.
Significance and Impact of the Study
These results give us a new insight of the intestinal damage caused by acute HS and the underlying mechanisms.
For 10,000 years pigs and humans have shared a close and complex relationship. From domestication to modern breeding practices, humans have shaped the genomes of domestic pigs. Here we present the ...assembly and analysis of the genome sequence of a female domestic Duroc pig (Sus scrofa) and a comparison with the genomes of wild and domestic pigs from Europe and Asia. Wild pigs emerged in South East Asia and subsequently spread across Eurasia. Our results reveal a deep phylogenetic split between European and Asian wild boars ∼1 million years ago, and a selective sweep analysis indicates selection on genes involved in RNA processing and regulation. Genes associated with immune response and olfaction exhibit fast evolution. Pigs have the largest repertoire of functional olfactory receptor genes, reflecting the importance of smell in this scavenging animal. The pig genome sequence provides an important resource for further improvements of this important livestock species, and our identification of many putative disease-causing variants extends the potential of the pig as a biomedical model.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The spatio-temporal expression patterns of Circular RNA (circRNA) across organs and developmental stages are critical for its function and evolution analysis. However, they remain largely unclear in ...mammals. Here, we comprehensively analysed circRNAs in nine organs and three skeletal muscles of Guizhou miniature pig (S. scrofa), a widely used biomedical model animal. We identified 5,934 circRNAs and analysed their molecular properties, sequence conservation, spatio-temporal expression pattern, potential function, and interaction with miRNAs. S. scrofa circRNAs show modest sequence conservation with human and mouse circRNAs, are flanked by long introns, exhibit low abundance, and are expressed dynamically in a spatio-temporally specific manner. S. scrofa circRNAs show the greatest abundance and complexity in the testis. Notably, 31% of circRNAs harbour well-conserved canonical miRNA seed matches, suggesting that some circRNAs act as miRNAs sponges. We identified 149 circRNAs potentially associated with muscle growth and found that their host genes were significantly involved in muscle development, contraction, chromatin modification, cation homeostasis, and ATP hydrolysis-coupled proton transport; moreover, this set of genes was markedly enriched in genes involved in tight junctions and the calcium signalling pathway. Finally, we constructed the first public S. scrofa circRNA database, allowing researchers to query comprehensive annotation, expression, and regulatory networks of circRNAs.
Despite recent efforts to characterize longitudinal variation in the swine gut microbiome, the extent to which a host's genome impacts the composition of its gut microbiome is not yet well understood ...in pigs. The objectives of this study were: i) to identify pig gut microbiome features associated with growth and fatness, ii) to estimate the heritability of those features, and, iii) to conduct a genome-wide association study exploring the relationship between those features and single nucleotide polymorphisms (SNP) in the pig genome. A total of 1,028 pigs were characterized. Animals were genotyped with the Illumina PorcineSNP60 Beadchip. Microbiome samples from fecal swabs were obtained at weaning (Wean), at mid-test during the growth trial (MidTest), and at the end of the growth trial (OffTest). Average daily gain was calculated from birth to week 14 of the growth trial, from weaning to week 14, from week 14 to week 22, and from week 14 to harvest. Backfat and loin depth were also measured at weeks 14 and 22. Heritability estimates (±SE) of Operational Taxonomic Units ranged from 0.025 (±0.0002) to 0.139 (±0.003), from 0.029 (±0.003) to 0.289 (±0.004), and from 0.025 (±0.003) to 0.545 (±0.034) at Wean, MidTest, and OffTest, respectively. Several SNP were significantly associated with taxa at the three time points. These SNP were located in genomic regions containing a total of 68 genes. This study provides new evidence linking gut microbiome composition with growth and carcass traits in swine, while also identifying putative host genetic markers associated with significant differences in the abundance of several prevalent microbiome features.
Heat stress (HS) jeopardizes pig health, reduces performance variables, and results in a fatter carcass. Whether HS directly or indirectly (via reduced feed intake) is responsible for the suboptimal ...production is not known. Crossbred gilts (n = 48; 35 ± 4 kg BW) were housed in constantly climate-controlled rooms in individual pens and exposed to 1) thermal-neutral (TN) conditions (20°C; 35% to 50% humidity) with ad libitum intake (n = 18), 2) HS conditions (35°C; 20% to 35% humidity) with ad libitum intake (n = 24), or 3) pair-fed PF in TN conditions (PFTN), n = 6, to eliminate confounding effects of dissimilar feed intake (FI). Pigs in the TN and HS conditions were sacrificed at 1, 3, or 7 d of environmental exposure, whereas the PFTN pigs were sacrificed after 7 d of experimental conditions. Individual rectal temperature (Tr), skin temperature (Ts), respiration rates (RR), and FI were determined daily. Pigs exposed to HS had an increase (P < 0.01) in Tr (39.3°C vs. 40.8°C) and a doubling in RR (54 vs. 107 breaths per minute). Heat-stressed pigs had an immediate (d 1) decrease (47%; P < 0.05) in FI, and this magnitude of reduction continued through d 7; by design the nutrient intake pattern for the PFTN controls mirrored the HS group. By d 7, the TN and HS pigs gained 7.76 and 1.65 kg BW, respectively, whereas the PFTN pigs lost 2.47 kg BW. Plasma insulin was increased (49%; P < 0.05) in d 7 HS pigs compared with PFTN controls. Compared with TN and HS pigs, on d 7 PFTN pigs had increased plasma NEFA concentrations (110%; P < 0.05). Compared with TN and PFTN controls, on d 7 circulating N(τ)-methylhistidine concentrations were increased (31%; P < 0.05) in HS pigs. In summary, despite similar nutrient intake, HS pigs gained more BW and had distinctly different postabsorptive bioenergetic variables compared with PFTN controls. Consequently, these heat-induced metabolic changes may in part explain the altered carcass phenotype observed in heat-stressed pigs.
Xenotransplantation is a promising strategy to alleviate the shortage of organs for human transplantation. In addition to the concerns about pig-to-human immunological compatibility, the risk of ...cross-species transmission of porcine endogenous retroviruses (PERVs) has impeded the clinical application of this approach. We previously demonstrated the feasibility of inactivating PERV activity in an immortalized pig cell line. We now confirm that PERVs infect human cells, and we observe the horizontal transfer of PERVs among human cells. Using CRISPR-Cas9, we inactivated all of the PERVs in a porcine primary cell line and generated PERV-inactivated pigs via somatic cell nuclear transfer. Our study highlights the value of PERV inactivation to prevent cross-species viral transmission and demonstrates the successful production of PERV-inactivated animals to address the safety concern in clinical xenotransplantation.
The clinical applicability of porcine xenotransplantation-a long-investigated alternative to the scarce availability of human organs for patients with organ failure-is limited by molecular ...incompatibilities between the immune systems of pigs and humans as well as by the risk of transmitting porcine endogenous retroviruses (PERVs). We recently showed the production of pigs with genomically inactivated PERVs. Here, using a combination of CRISPR-Cas9 and transposon technologies, we show that pigs with all PERVs inactivated can also be genetically engineered to eliminate three xenoantigens and to express nine human transgenes that enhance the pigs' immunological compatibility and blood-coagulation compatibility with humans. The engineered pigs exhibit normal physiology, fertility and germline transmission of the 13 genes and 42 alleles edited. Using in vitro assays, we show that cells from the engineered pigs are resistant to human humoral rejection, cell-mediated damage and pathogenesis associated with dysregulated coagulation. The extensive genome engineering of pigs for greater compatibility with the human immune system may eventually enable safe and effective porcine xenotransplantation.
Nursing mother and breed can differently regulate early-life microbiota succession in pigs. However, it remains unclear whether they affect gastrointestinal microbiota and immune status, which are ...critical for early-life gut health. Here, an interspecific cross-fostering piglet model was employed by fostering neonatal Yorkshire and Meishan piglets to the same or another breed of sows. Jejunal and colonic microbiotas and mucosal immune parameters were analyzed at postnatal days 14 (preweaning) and 49 (postweaning). Nursing mother affected 10 genera in the colon and 3 minor genera in the jejunum. At day 14, Meishan sow-nursed piglets had lower
and higher
counts in the colonic digesta and larger amounts of interleukin 10 and Foxp3-positive cells in the colonic mucosa than did Yorkshire sow-nursed piglets. At day 49, nursing mother had no significant effects on cytokine expression. Breed effects were observed; Meishan piglets had lower relative abundances of
and lower gene expression of tumor necrosis factor alpha (TNF-α) than those of Yorkshire piglets at days 14 and 49. Collectively, nursing mother mainly affected preweaning colonic microbiota and immune status, while breed effects persisted after weaning. Piglets nursed by Meishan sows had different microbiota compositions and inflammatory cytokine profiles in the colon compared with those of piglets nursed by Yorkshire sows. These results highlight the different role of nursing mother and breed in affecting early gut microenvironment.
Early-life gut microbiota and immune status are pivotal for postnatal growth. By using an interspecific cross-fostering piglet model, we find that change in nursing mother transiently reshapes preweaning colon microbiota and immune status, while breed shows persistent effects both pre- and postweaning. Piglets nursed by Meishan sows had lower
counts and higher anti-inflammatory cytokine expression. These results highlight the significance of nursing mother in regulating early-life gut health.
The present study was conducted to evaluate the effects of early administration of Lactobacillus fermentum I5007 on intestinal development and microbial composition in the gastrointestinal tract ...using a neonatal piglet model. Full-term 4 day old piglets, fed with milk replacer, were divided into a control group (given placebo of 0.1% peptone water) and a L. fermentum I5007 group (dosed daily with 6 × 109 CFU/mL L. fermentum I5007). The experiment lasted 14 days. On day 14, a significant increase in the jejunum villous height (583 ± 33 vs 526 ± 18) and increases in the concentrations of butyrate (7.55 ± 0.55 vs 5.33 ± 0.39) and branched chain fatty acids in the colonic digesta were observed in piglets in the L. fermentum I5007 treatment (P < 0.05). mRNA expression of IL-1β (1.29 ± 0.29 vs. 0.62 ± 0.07) in the ileum were lower after 14 days of treatment with L. fermentum I5007. Denaturing gradient gel electrophoresis (DGGE) revealed that L. fermentum I5007 affected the colonic microbial communities on day 14 and, in particular, reduced numbers of Clostridium sp. L. fermentum I5007 play a positive role in gut development in neonatal piglets by modulating microbial composition, intestinal development, and immune status. L. fermentum I5007 may be useful as a probiotic for application in neonatal piglets.
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