Search Results (155)

Automated pig-welfare monitoring needs scalable, non-invasive signals that work across ages and individuals. A key methodological contribution of this study is the use of subject-wise validation, which ensures generalization to unseen animals and prevents inflated accuracy caused by growth-related and individual ‘voice’ differences. Vocalizations can help, but growth and individual “voice” differences can confound distress patterns and overstate accuracy without subject-wise validation. In our study, we explicitly accounted for individual variability by including animal identity as a random effect in mixed models and by using grouped cross-validation, where models were tested only on pigs not seen during training. This approach ensures that the reported accuracy reflects generalization across different individuals rather than memorization of specific vocal signatures. We analyzed 2221 vocal samples from 40 pigs (20 males, 20 females) recorded across four growth phases (farrowing, nursery, growing, finishing) under six conditions (pain, hunger, thirst, cold stress, heat stress, normal). Acoustic features extracted in Praat included energy, duration, intensity, pitch, and formants (F1–F4). Using blockwise variance decomposition, we quantified contributions of distress exposure, growth phase, and sex, and estimated the additional variance explained by animal identity. Distress exposure dominated intensity and spectral traits, particularly Formant 2, whereas the growth phase produced systematic shifts in duration and pitch. Animal identity added a modest but consistent increment in explained variance (~+0.02–0.03 R² beyond sex, phase, and distress). For prediction, we used 5-fold cross-validation grouped by animal. A Random Forest achieved a modest balanced accuracy of 0.609 and macro-F1 of 0.597; pain was most separable (recall 0.825), while other states showed moderate recall, indicating overlap. These results support hierarchical acoustic encoding of distress and establish a benchmark for precision welfare monitoring. Furthermore, they highlight that resolving complex physiological overlaps, such as heat stress and resource competition, requires a shift from unimodal acoustic models to multimodal Precision Livestock Farming (PLF) systems that integrate bioacoustics with continuous environmental and behavioral data streams. Full article

This study investigated the effects of compound microbial fermented feed on the growth performance, intestinal architecture, microbiota composition, and metabolic profiles of weaned piglets. Fifty-four weaned piglets were randomly allocated to three dietary treatment groups: a control group (basal diet), a 50% fermented feed group (T1), and a 100% fermented feed group (T2), for a 33-day feeding period. The results indicated that both T1 and T2 diets significantly improved final body weight and average daily gain (ADG), while decreasing the feed-to-gain ratio (F/G) compared with the control (p < 0.05). Morphological assessment revealed that the T1 group significantly elevated the villus height-to-crypt depth ratio in the jejunum and increased the density of goblet cells in the cecum and colon (p < 0.05). Multi-omics analysis indicated that fermented feed significantly reshaped the gut microbiota structure (p < 0.05), characterized by the enrichment of beneficial taxa, including Oscillospiraceae and Lachnospiraceae (p < 0.05), and the modulation of nucleotide and bile acid metabolism. Furthermore, correlation analysis identified significant linkages between the abundance of jejunal Oscillospiraceae and colonic/cecal Lactobacillus with growth performance, intestinal morphology, and key metabolites. This finding systematically elucidates the mechanisms by which compound microbial fermented feed promotes growth and intestinal health in weaned piglets via microbiota-mediated pathways, offering a robust scientific framework for the development of antibiotic-free nutritional strategies. Full article

The mycotoxin deoxynivalenol (DON) is a common contaminant found in swine diets, causing decreased growth performance and poor health. Additionally, F18 enterotoxigenic E. coli is a leading cause of post-weaning diarrhea. Nursery pigs are often exposed to each of them after weaning; however, it is unknown what impact the combination of these stressors has on gastrointestinal health. Therefore, the objective of this study was to investigate the effect of pre-exposure to DON on the response of intestinal porcine epithelial cells (IPEC-J2) to challenge with enterotoxigenic F18 E. coli. Four groups were compared: Control (untreated cells), DON (cells treated with 0.5 μM DON for 24 h), F18 E. coli (multiplicity of infection 5:1, varied duration) and DON + E. coli (DON treatment with subsequent E. coli infection). Gene expression of IL-8, IL-6 and TNFα was significantly increased in cells infected with E. coli for 3 h vs. uninfected cells (p < 0.0001, p < 0.0001 and p < 0.0001, respectively). There was an interactive effect between DON and E. coli on IL-8 gene expression; cells pretreated with DON before E. coli infection had a higher expression of IL-8 than those not pretreated (p < 0.05). The concentration of IL-8 protein was significantly increased by E. coli (p < 0.0001). Claudin 1 and Occludin protein abundance were reduced by E. coli as measured by Western blot. Cytotoxicity was increased by E. coli vs. Control (p < 0.05). Pretreatment with DON increased the amount of E. coli that adhered to IPEC-J2 cells (p < 0.01) 30 min post-infection. FITC-dextran passage was increased in the DON + E. coli treatment vs. E. coli alone (p < 0.0001). Transepithelial electrical resistance (TEER) was decreased by DON when compared to untreated cells at 0 h (p < 0.0001). Similarly, DON + E. coli exhibited lower TEER vs. E. coli alone at 2 h post-infection (p < 0.0001). Taken together, these results indicate that DON pre-exposure increased the severity of E. coli infection on endpoints such as barrier permeability and E. coli adhesion. Full article

This study evaluated the effects of dietary 25-hydroxycholecalciferol alone or in combination with vitamin D₃ (VD₃) on growth performance, vitamin D status, immune parameters, bone integrity, and antioxidant capacity in nursery pigs. Sixty weanling piglets (5.63 ± 0.98 kg initial body weight) were assigned to three treatments for a 28 d feeding trial. The treatments were a basal diet supplemented with 2000 IU/kg VD₃, a combination of 1000 IU/kg VD₃ and 1000 IU/kg 25-hydroxycholecalciferol (25-OHD₃), and 2000 IU/kg 25-OHD₃. Pigs fed diets containing 25-OHD₃ tended to have greater feed intake during d 14–28 (p = 0.06). Plasma 25-OHD₃ concentrations were greater in pigs fed diets containing 25-OHD₃ than in those fed VD₃ alone on d 14 and 28 (p < 0.05), with greater values observed in pigs fed 2000 IU/kg 25-OHD₃ than in those fed a combination of 1000 IU/kg VD₃ and 1000 IU/kg 25-OHD₃ on d 14 (p < 0.05). Pigs fed diets supplemented with 25-OHD₃ had lower plasma malondialdehyde concentrations at d 28 (p < 0.05), while immune parameters and bone mineralization indicators were unaffected. In the broken-line analysis, the estimated plasma 25-OHD₃ concentration for plasma malondialdehyde concentrations to reach the minimum level was 32.5 ng/mL (p < 0.05). In conclusion, supplementing 25-OHD₃ in nursery diets improved blood vitamin D status and could help reduce oxidative stress during the late nursery period. Full article

Non-starch polysaccharides (NSPs) in plant-based swine diets can reduce nutrient availability, and the use of exogenous NSP-degrading enzymes has been proposed as a practical approach to improve digestive utilization. This study examined the effects of a commercial enzyme mixture through both in vitro assessment and an in vivo trial in nursery pigs. The in vitro evaluation of seven commercial diets showed that enzyme supplementation increased dry matter, crude protein, crude fat, and crude fiber digestibility, with the most notable improvements observed in finisher, gestating, and lactating diets. In the in vivo experiment, pigs fed the enzyme-supplemented diet showed higher average daily gain (464 vs. 361 g/d; p = 0.07) and an improved feed conversion ratio (1.82 vs. 2.39; p = 0.07), together with numerically greater cecal butyrate concentration (2.13 vs. 1.06 mmol/dL; p = 0.10) and increased villous height in the jejunum and ileum. Although these responses did not reach statistical significance, they represent consistent trends that align with the in vitro findings and suggest potential benefits in nutrient utilization and gut morphology. Overall, the results indicate that NSP enzyme supplementation may support digestive function under specific dietary conditions, particularly in diets containing moderate to high NSP levels, and provide useful information for its practical application in swine nutrition. Full article

Low-protein diets are increasingly used in nursery pigs to reduce nitrogen excretion and control post-weaning diarrhea. Niacinamide, as a bioavailable form of niacin, improves protein metabolic regulation and nitrogen utilization via promoting energy metabolism, redox balance, and intestinal integrity. In addition, synergistic effects in enhancing anti-inflammation and protecting against environmental stress are reported by combining niacinamide and Zn. The levels of dietary niacinamide for optimal growth and intestinal health were determined in two experiments using nursery pigs fed a low-protein diet with and without the addition of 0.2% ZnO. The diets were supplemented with 0, 30, 130, 230, or 330 mg/kg niacinamide. In Exp. 1, niacinamide quadratically improved (p < 0.05) growth performance with optimal effects at 50 mg/kg, increased hemoglobin (HGB) and mean corpuscular volume, and decreased diarrhea occurrence (p < 0.05) at 140 mg/kg in the diet with ZnO. In Exp. 2, niacinamide improved feed efficiency (p < 0.05) peaked at 130 mg/kg, and serum HGB and immunoglobulin A (p < 0.05) peaked at 170 mg/kg while decreasing diarrhea occurrence (p < 0.05) by up to 315 mg/kg in the pigs with no ZnO. The level of niacinamide required for optimal growth and intestinal health was associated with Zn availability. Full article

Antimicrobial resistance (AMR) is a significant global health concern, and the use of antibiotics in livestock, including swine production, is a major contributor. Vaccines offer a promising alternative for controlling bacterial infections in pigs, but their widespread use is often hindered by biological, economic, and practical challenges. This study surveyed U.S. swine veterinarians to identify which bacterial diseases require better vaccines and to understand the barriers to their adoption. Nineteen veterinarians with an average of 24.7 years of experience were surveyed across 21 states. The results identified Streptococcus suis, Escherichia coli, Mycoplasma hyopneumoniae, and Glaesserella parasuis as the most critical pathogens needing improved vaccines. Veterinarians anticipated significant improvements in vaccine efficacy for S. suis and E. coli during the nursery stage and expressed a willingness to pay 1.8 and 1.9 times their current prices, respectively. While expectations for M. hyo vaccine improvements were not significant, veterinarians expressed the highest willingness to pay (4.2 times the current price), citing the potential for disease eradication. This research highlights that developing effective vaccines for S. suis and E. coli should be the most urgent priority due to their significant economic impact and rising AMR concerns. However, M. hyo vaccine development holds the most economic potential due to the possibility of eradication. Our research provides a roadmap for future efforts to combat AMR in the swine industry, emphasizing key economic, policy, and educational considerations for successful vaccine implementation. Full article

The gut microbiota plays a crucial role in maintaining swine health and understanding its stage-specific variations provides a scientific basis for health assessment. This study investigated the structural changes in intestinal microbiota during the development of Sichuan–Tibetan black pigs (n = 15) by collecting fecal samples at three growth stages: the nursery period (1 month), growing period (3 months), and finishing period (10 months). Microbial profiling was performed using 16S rRNA sequencing. Results showed no significant difference in the Shannon index between the nursery and growing periods, while the finishing period exhibited distinct ACE and Chao 1 indices compared to other stages. PCoA and NMDS analyses revealed significant structural divergence in the finishing period microbiota, with greater intra-group variability observed in the nursery and growing periods. At the phylum level, Firmicutes abundance increased progressively with growth, becoming the absolute dominant phylum, whereas Bacteroidota showed a declining trend. These characteristics are particularly prominent during the finishing period. At the family level, Lactobacillaceae abundance increased continuously. Oscillospiraceae remained stable during the early stages but decreased significantly in the finishing period. Genus-level analysis shows that Lactobacillus, especially L. amylovorus and L. reuteri, become dominant bacterial species during the finishing period. A total of 84 differentially abundant core microbiota were identified, with the finishing period containing the highest number. Functional annotation revealed 19 significantly different metabolic pathways across the three stages. The most significant is the enhanced activity of microorganisms during the finishing period in pathogen-related metabolism and exogenous degradation, reflecting their adaptability to complex feed. These findings demonstrate stage-dependent variations in the gut microbiota of Sichuan–Tibetan black pigs, providing valuable references for nutritional regulation and feeding management practices. Full article

Background: Porcine circovirus type 2 (PCV2) is the primary pathogen responsible for postweaning multisystemic wasting syndrome (PMWS) and related diseases, leading to significant economic losses in the global pig industry. Methods: This study conducted a thorough epidemiological survey between 2022 and 2024, gathering 6600 samples from 24 large-scale pig farms in Hubei Province. On the basis of these findings, the immune response and economic benefits of two representative commercial PCV2 subunit vaccines, recombinant baculovirus CP08 and Ingelvac CircoFLEX^®, were assessed in a modern fattening farm in Xiangyang city. Results: The results indicated no detection of viral antigens in sows; however, weaned piglets and fattening pigs presented high positivity rates, with 8-week-old nursery pigs identified as the peak period for infection. Both vaccines significantly improved average weight gain and reduced antigen positivity, with Ingelvac CircoFLEX^® demonstrating superior viral control and economic returns. Conclusions: This study offers valuable scientific and practical guidance for PCV2 control strategies and vaccine selection in Hubei and comparable regions. Full article

Porcine reproductive and respiratory syndrome virus (PRRSV) is a significant cause of economic loss in the swine industry, yet its control remains challenging in wean-to-harvest sites. This prospective observational study followed 95 wean-to-harvest sites across six U.S. states for one production cycle. Sites were required to be PRRSV-negative or vaccinated with a modified live virus (MLV) and free of major coronaviruses. Outbreaks were defined as RT-qPCR-positive in unvaccinated sites or detection of ORF5 sequences distinct from the MLV strain. Biosecurity data were collected through a survey, and oral fluids were tested every four weeks. PRRS outbreaks occurred in 14/42 nurseries (33.3%), 8/12 wean-to-finish (66.7%), and 35/41 finishers (82.4%), with lineage 1C.5 most frequently detected. In univariate models, higher odds of outbreaks were associated with transporting pigs of unknown status (OR 9.80, 1.73–55.37), rendering (OR 6.47, 1.62–25.84), and employee cohabitation (OR 6.15, 1.51–25.09). Protective factors included exclusive pumping equipment (OR 0.07, 0.01–0.43) and overnight downtime for multi-site workers (OR 0.15, 0.04–0.56). In multivariable models, finisher sites (OR 17.47, 2.44–125.19) and greater swine site density within one mile (OR 1.62, 1.09–2.41) significantly increased outbreak odds. These results support targeted biosecurity practices, helping farmers and the swine industry reduce PRRS outbreaks. Full article

Senecavirus A (SVA) is an emerging threat to swine populations due to its potential to cause vesicular lesions, which are difficult to differentiate from other vesicular diseases of swine such as foot and mouth disease (FMD), requiring significant resources for differential diagnosis. The first Taiwanese isolate of SVA was identified in 2006, although the first clinical case was not reported until 2012. The genetic characteristics and seroprevalence of SVA in Taiwan remain unclear. This study aimed to assess the seroprevalence and genetic diversity of SVA in nursery/weaned swine and finisher swine on Taiwanese pig farms. Phylogenetic analysis of seven Taiwanese SVA isolates revealed clustering into groups I and II. The 2006 and 2012 isolates shared 95.5% and 95.7% identity, respectively, with an early USA strain (MT360258), while more recent strains collected between 2018 and 2022 exhibited 95.7–98.8% identity with a 2020 USA strain (MZ733977). Serological analysis of swine from 300 farms showed significantly higher herd-level seroprevalence in nursery/weaned swine (53%) than finisher swine (6.7%). Furthermore, comparative analysis of nine known B cell epitopes showed high sequence conservation across Taiwanese and global strains. These findings provide important baseline data on the genetic diversity and seroprevalence of SVA in Taiwan and support the development of improved surveillance strategies for this emerging swine pathogen. Full article

After in vitro mycotoxin binding validation, humate and β-mannanase were tested for mitigating the negative effects of aflatoxin B₁ and deoxynivalenol. Gilts at 8.7 ± 0.5 kg body weight were allotted to four treatments: NC (uncontaminated diet); PC (contaminated diet: 150 µg aflatoxin B₁ and 1100 µg deoxynivalenol per kg feed); HT (PC + humate, 0.5%); and EM (PC + β-mannanase, 800 U/kg diet). Growth performance was recorded for 42 days, and blood and tissue samples were collected for hematological and histopathological evaluations. The PC reduced (p < 0.05) serum tumor necrosis factor-α at day 28 and tended to increase (p = 0.062) immunoglobulin G (IgG), whereas the EM reduced IgG (p < 0.05) at day 42. The PC increased (p < 0.05) mean corpuscular hemoglobin and volume, which were reduced (p < 0.05) by HT or EM at day 42. The PC increased (p < 0.05) bile duct hyperplasia, which was attenuated (p < 0.05) by HT or EM. The PC reduced (p < 0.05) gain- to-feed ratio for the overall period, whereas HT increased (p < 0.05) average daily gain on days 21 to 28. These results suggest that HT and EM may mitigate mycotoxin-induced immune and hepatic damage in pigs through adsorbing mycotoxins. Full article

The diagnosis of swine influenza A virus (swIAV) has to involve laboratory detection, as the clinical signs are not pathognomonic. Nasal swabs (NSs) have been the preferred sample material for swIAV PCR diagnostics, but oral fluid (OF) is a convenient alternative material. In this study, NSs and OFs from 35 Polish swine herds were collected and tested with real-time RT-PCR in order to assess swIAV circulation patterns in Poland and improve protocols for efficient, non-invasive and cost-effective swIAV surveillance in pig farms. The study showed that the swIAV RNA was detected in 65.7% of the tested farms. In total, 21.2% of NS pools and 48.6% of OF samples were positive for swIAV. The Ct values in NS pools and OFs were similar (p > 0.05), but a significant reduction (p < 0.05) in swIAV prevalence in NSs was observed in nursery pigs from farms applying swIAV vaccinations. Successful subtyping was achieved more effectively with OFs compared to NSs, and the H1avN2 was most prevalent subtype detected. The results emphasized that OF can be useful for monitoring swIAV and subtyping. However, OFs cannot replace NSs, which were more useful in the assessment of the effect of swIAV vaccinations in nursery pigs. Full article

Zinc is an essential trace mineral for livestock, but excessive use can contribute to ecotoxicity and antimicrobial resistance. The objective of this study was to assess the impact of different zinc oxide (ZnO) levels in diets for weaned pigs on growth performance, mortality, dietary zinc flow, and environmental impacts. A 6-week feeding trial with 432 weaned pigs assessed three dietary treatments: high ZnO (pharmaceutical levels), intermediate ZnO, and low ZnO (EU recommendation). Growth performance for the growing–finishing period was modeled using the NRC (2012), and dietary Zn intake and fecal Zn excretion were estimated. Environmental impacts were analyzed via life cycle assessment (LCA) using SimaPro LCA software. High ZnO improved growth performance and reduced mortality (p < 0.05), but increased nursery fecal zinc excretion, resulting in a total fecal Zn excretion per pig of 54,125 mg, 59,485 mg, and 106,043 mg for low-, intermediate-, and high-ZnO treatments, respectively. In the nursery phase, high-ZnO treatment had the greatest impact on environmental footprint, increasing freshwater ecotoxicity and marine ecotoxicity indicators by 59.6% and 57.9%, respectively. However, high-ZnO-fed pigs had a greater body weight at the end of the nursery phase and were predicted to achieve a higher growth rate per 130 kg market pig, with fewer days to market and by sparing feed. Therefore, high-ZnO-fed pigs had reduced environmental burdens, including global warming potential, ozone depletion, land use, and mineral resource depletion. These findings demonstrate how livestock nutritionists can apply integrated modeling approaches to link animal performance with environmental outcomes within a One Health framework. Full article

This study evaluated the effects of dietary hydroxytyrosol (HT) addition on piglets during the nursery phase across two experiments. In the first, 72 weaned male piglets (~26 days old, 7.3 ± 0.5 kg) were assigned to one of four diets containing 0, 5, 10, or 50 mg HT/kg feed. Growth performance, serum biochemistry, histological and behavioral parameters, and meat lipid profiles were assessed. In the second study, the apparent digestibility of diets containing 0, 25, or 50 mg HT/kg feed was evaluated using 15 male piglets (21.5 ± 1.5 kg) through total excreta collection. Results revealed that HT influenced serum glucose and gamma-glutamyl transferase, histological inflammation, and active behaviors. HT modified lipid profiles, reduced capric, lauric, linolenic, arachidonic, cis-5,8,11,14,17-eicosapentaenoic fatty acid concentrations, and increased the nervonic acid profile. The digestibility of dry matter, organic matter, energy, and protein increased with HT use up to 50 mg/kg of feed. These findings demonstrate that HT positively impacts piglet efficiency, changing the fatty acid profile with increased nervonic acid, highlighting its potential as a dietary additive for improving nursery pig production. Full article