One Health challenges for pig reproduction

Worldwide perspective for swine production and reproduction for the next 20 years

Over numerous years, breeding herds have faced challenges to sustainability with poor profitability, impact of disease, export market instability, limited labor, and increasing environmental and animal welfare regulations. Many of these scenarios are expected to continue, but their impact lessened with adjustments in management, technology, and business. The prospects for success in the future for the pig industry in various locations are based on costs of pig production efficiency and projections for domestic and export markets. Sow farms are expected to increase in size to meet large retailer needs, while smaller farms will fill domestic regional markets. The risk of PRRS in breeding herds and loss of pigs and infertility will continue to be a major concern for producers. Changes in sow housing will likely continue with designs that meet welfare requirements and allow for practical management of the breeding herd. Trends for selection and increase in litter size will continue but will include measures for birthweight and survival, and traits for heat stress and disease resistance. Changes in boar semen production and AI procedures are unlikely since fertility measures are very high. But advances in technology for identifying fertile and time of ovulation, or procedures that aid in selection of sperm or induction of ovulation, could facilitate reduction in the number of sperm used to produce a litter of pigs.

Oxidative Stress and Autophagy: Unraveling the Hidden Threat to Boars' Fertility

This review systematically examines the influence of oxidative stress on the reproductive function of male livestock, with a particular focus on the modulation of autophagy. Spermatogenesis, a highly precise biological process, is vulnerable to a range of internal and external factors, among which oxidative stress notably disrupts autophagic processes within the testes. This disruption results in diminished sperm quality, impaired testosterone synthesis, and compromised integrity of the blood-testis barrier. Furthermore, this review elucidates the molecular mechanisms by which oxidative stress-induced autophagy dysfunction impairs spermatogenesis and mitochondrial function, consequently reducing sperm motility. These findings aim to provide a theoretical foundation and serve as a reference for improving reproductive performance and sperm quality in livestock.

Effect of SNPs on Litter Size in Swine

Although sows do not directly enter the market, they play an important role in piglet breeding on farms. They consume large amounts of feed, resulting in a significant environmental burden. Pig farms can increase their income and reduce environmental pollution by increasing the litter size (LS) of swine. PCR-RFLP/SSCP and GWAS are common methods to evaluate single-nucleotide polymorphisms (SNPs) in candidate genes. We conducted a systematic meta-analysis of the effect of SNPs on pig LS. We collected and analysed data published over the past 30 years using traditional and network meta-analyses. Trial sequential analysis (TSA) was used to analyse population data. Gene set enrichment analysis and protein-protein interaction network analysis were used to analyse the GWAS dataset. The results showed that the candidate genes were positively correlated with LS, and defects in PCR-RFLP/SSCP affected the reliability of candidate gene results. However, the genotypes with high and low LSs did not have a significant advantage. Current breeding and management practices for sows should consider increasing the LS while reducing lactation length and minimizing the sows' non-pregnancy period as much as possible.

Survey on resistance occurrence for F4+ and F18+ enterotoxigenic Escherichia coli (ETEC) among pigs reared in Central Italy regions

Porcine Post Weaning Diarrhoea (PWD) is one of the most important swine disease worldwide, caused by Enterotoxigenic Escherichia coli (ETEC) strains able to provoke management, welfare and sanitary issues. ETEC is determined by proteinaceous surface appendages. Numerous studies conducted by now in pigs have demonstrated, at the enterocytes level, that, the genes mucin 4 (MUC4) and fucosyltransferase (FUT1), coding for ETEC F4 and F18 receptors respectively, can be carriers of single nucleotide polymorphisms (SNPs) associated with natural resistance/susceptibility to PWD. The latter aspect was investigated in this study, evaluating the SNPs of the MUC4 and FUT1 genes in slaughtered pigs reared for the most in Central Italy. Genomic DNA was extracted from 362 swine diaphragmatic samples and then was subjected to the detection of known polymorphisms on MUC4 and FUT1candidate target genes by PCR-RFLP. Some of the identified SNPs were confirmed by sequencing analysis. Animals carrying the SNPs associated with resistance were 11% and 86% for the FUT1 and MUC4 genes respectively. Therefore, it can be assumed that the investigated animals may be an important resource and reservoir of favorable genetic traits for the breeding of pigs resistant to enterotoxigenic E.coli F4 variant.