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Gamma-interferon-inducible lysosomal thiol reductase (GILT) plays pivotal roles in both adaptive and innate immunities. GILT exhibits constitutive expression within antigen-presenting cells, whereas in other cell types, its expression is induced by interferon gamma (IFN-γ). Gaining insights into the precise molecular mechanism governing the induction of GILT protein by IFN-γ is of paramount importance for adaptive and innate immunities. In this study, we found that the 5' segment of GILT mRNA inhibited GILT protein expression regardless of the presence of IFN-γ. Conversely, the 3' segment of GILT mRNA suppressed GILT protein expression in the absence of IFN-γ, but it loses this inhibitory effect in its presence. Although the mTOR inhibitor rapamycin suppressed the induction of GILT protein expression by IFN-γ, the expression from luciferase sequence containing the 3' segment of GILT mRNA was resistant to rapamycin in the presence of IFN-γ, but not in its absence. Collectively, this study elucidates the mechanism behind GILT induction by IFN-γ: in the absence of IFN-γ, GILT mRNA is constitutively transcribed, but the translation process is hindered by both the 5' and 3' segments. Upon exposure to IFN-γ, a translation inhibitor bound to the 3' segment is liberated, and a translation activator interacts with the 3' segment to trigger the initiation of GILT translation.

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Fifty gilts (initial body weight [BW] 190.7 ±â€…4.2 kg) were recruited on day 85 of gestation and were used until day 19 of lactation to assess the dose-response of inactivated yeast via hydrolyzation (HY) inclusion on offspring growth and immunoglobulin (Ig) transfer prior to weaning. Gilts were assigned to one of the 5 experimental diets: a control with no HY (HY0) or inclusion of 0.25% (HY0.25), 0.5% (HY0.5), 1.0% (HY1.0), or 1.2% (HY1.2) HY. Gilts were weighed on days 85 and 110 of gestation and days 1 and 19 (weaning) after farrowing. Offspring were weighed on days 1 and 19 of age. On lactation day 1 (approximately 24 h after farrowing), colostrum, gilt plasma, and plasma from 2 median BW piglets were collected and on day 19, plasma from each gilt and 2 median BW piglets per litter were collected for determination of Ig concentrations. Contrast statements were used to assess the linear, quadratic, cubic, and quartic effects of HY inclusion. The inclusion of HY had minimal effects on gilt BW or litter characteristics at birth (total number born and born alive, piglet birth weight). Lactation average daily feed intake of the gilts tended to increase then decrease with increasing HY inclusion (quadratic; P = 0.085). Piglet preweaning average daily gain (linear, quadratic, and quartic; P < 0.05) and BW at weaning (quadratic and quartic; P < 0.05) increased then decreased with increasing HY inclusion. On lactation day 1, colostrum and gilt plasma Ig concentrations were not affected by dietary treatment (P > 0.10) but piglet IgA and IgM decreased then increased with HY inclusion level (cubic; P < 0.05). On lactation day 19, piglet plasma IgG tended to increase with HY inclusion (linear; P = 0.099). In summary, increasing HY inclusion in late gestating and lactating gilt diets improved immune transfer in the first 24 h after birth and piglet preweaning growth rates and BW at weaning. Therefore, maternal feeding of HY could be used as a strategy to improve offspring immunocompetence and BW at weaning, with possible carryover benefits for the postweaning phase.

Abrupt weaning exposes piglets to various stressors that result in a period after weaning with little or no weight gain or feed intake and increased incidence of morbidity and mortality. Inactivated yeast via hydrolyzation (HY) is a functional feed additive that can improve the immune response in pigs. The low and variable feed intakes immediately after weaning render feed additives less useful in nursery pig diets, therefore, enhancing immunocompetence prior to weaning could be a strategy to improve offspring outcomes. This study tested 4 levels of HY (0.25%, 0.5%, 1.0%, and 1.2%) and control (0%) fed to gestating and lactating gilts from day 85 of gestation until day 19 of lactation when piglets were weaned. Plasma immunoglobulin (Ig) concentrations and preweaning offspring growth rates were assessed. It was found that piglet preweaning average daily gain and body weight at weaning were improved with increasing inclusion of HY in the maternal diet, which corresponded to increased plasma IgA and IgM concentrations for the offspring after birth. Greater body weight at weaning and greater plasma IgA and IgM concentration have the potential to attenuate the postweaning growth lag in addition to improving immunocompetence around weaning.

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Total protein levels in fish are widely used in health and welfare studies, providing a simple and accessible measure. However, the multifaceted role of blood proteins makes it sometimes challenging to link total protein content to specific health issues, while specific protein fractions may offer more precise insights into fish biology and health, particularly in farmed fish species where such data is often lacking. Data were gathered from two experiments involving Dicentrarchus labrax and Sparus aurata, key species in European marine aquaculture. The aim was (1) to assess how different globulin fractions contribute to total protein content in blood and (2) how these contributions vary across different sampling times in healthy animals. In D. labrax, the beta1 globulin fraction emerged as the major contributor (34.16%), followed by albumin and alpha2 globulins (18.24% and 16.41%, respectively). In contrast, pre-albumins and alpha1 fractions had the least contribution (5.49% and 7.71%). S. aurata exhibited albumin as the primary contributor (23.39%), followed by beta1 and alpha2 globulins (19.71% and 19.15%, respectively), with gamma and alpha1 fractions contributing the least (5.34% and 8.63%). Notably, the study revealed relatively stable contributions of globulin fractions to total proteins within both species, albeit with minor variations over time, potentially linked to environmental and individual factors. Furthermore, larger fish displayed higher total protein levels. This research underscores the need for further investigation into the diverse factors influencing globulin contributions to total proteins, ultimately enhancing health and welfare monitoring for farmed fish species.

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The goal of this project was to determine whether various measures of mammary development differed between gilts and multiparous sows at the end of gestation. During gestation, Yorkshire × Landrace gilts (n = 19) and sows (second and third gestations, n = 17) were fed one daily meal of a conventional corn-based diet, where the amount fed was based on body weight (BW) and backfat thickness (BF) at mating. On day 110 ±â€…1 of gestation, a jugular blood sample was obtained from all gilts and sows to measure insulin-like growth factor-1 (IGF-1), glucose, free fatty acids, and urea. On that same day, BW and BF were measured and animals were euthanized. Mammary glands from one side of the udder were dissected for compositional analyses. The fifth gland of the contralateral row of mammary glands was sampled for histology and immunohistochemical localization of Ki67. There was less total parenchyma (1,437.4 vs. 2,004.7 ±â€…127.1 g; P < 0.001) and total extraparenchymal tissue (1,691.0 vs. 2,407.0 ±â€…125.3 g; P < 0.001) in mammary glands of gilts compared to those from sows. When these values were expressed per kg BW (226.0 and 284.0 ±â€…2.7 kg for gilts and sows, respectively), parenchymal mass did not differ (P > 0.10), while extraparenchymal tissue weight tended to be less in gilts than sows (P = 0.07). All components within the parenchyma differed by parity (P < 0.001). Specifically, parenchymal tissue from gilts contained a greater proportion of fat and dry matter (DM), a lower proportion of protein, and lower concentrations of DNA (6.59 vs. 9.35 ±â€…0.53 mg/g DM) and RNA (7.76 vs. 12.33 ±â€…0.70 mg/g DM) than that from sows. On the other hand, the circumference of alveolar lumens was greater in gilts than sows (P < 0.001), while the percentage of epithelial cells that were positive for Ki67, a marker of cell proliferation, was greater in sows than gilts (P < 0.05). Circulating concentrations of IGF-1 were greater in gilts than in multiparous sows (45.0 vs. 27.3 ±â€…2.8 ng/mL, P < 0.001). None of the other blood variables were changed by parity. Results show a marked effect of parity on mammary gland development in swine. At the end of gestation, the mammary glands of gilts had less parenchyma with lower epithelial proliferation than glands from multiparous sows. These differences could alter the response of mammary tissue to various nutritional or endocrine signals. This information is crucial for the development of management strategies designed to maximize sow milk yield.

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The elimination of ejaculates and males with low fertility despite good sperm motility and morphology is crucial to maintain high pregnancy rates after artificial insemination (AI) in farm animals. The ability of sperm to survive in the female tract is particularly crucial in pigs due to the large variation in the timing between AI and ovulation and the high number of oocytes to fertilise. The objective of this study was to characterise a new in vitro model of oviduct sperm reservoir using porcine oviduct epithelial spheroids (OES) and to assess the variability in sperm binding to OES among gilts, boars and their ejaculates. Isthmic mucosa fragments were collected from gilt oviducts at a slaughterhouse, and after 48 h of culture, the OES that had spontaneously formed were sorted according to their vesicle shape and size (150-200 µm in diameter) for characterisation and sperm binding assays. The OES contained viable, cytokeratin-positive and vimentin-negative cells, of which 36.4 ± 2.0% were multiciliated. The average proportion of multiciliated cells per OES did not change among culture replicates. After co-incubation with boar fresh semen, only sperm of normal morphology were found to bind, by their head, to cilia of OES. The density of sperm bound to the OES surface increased linearly with sperm concentration. The bound sperm density on OES was used to assess the binding capacity of fresh ejaculates collected from Pietrain boars. For a given ejaculate, the bound sperm density did not vary among pools of OES female donors. The analysis of five successive ejaculates from nine boars indicated significant differences in bound sperm densities on the OES among individual boars and their ejaculates (P < 0.01). There was no correlation between the sperm bound density and sperm parameters measured by computer-assisted sperm analysis or the initial dilution of the ejaculate. In conclusion, the OES characterised in this study offered physiological conditions to study sperm binding to the isthmic reservoir and evidenced that sperm from different ejaculates and different boars vary in their ability to bind to these oviduct spheroids despite homogeneous motility and morphology.

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Progeny born to primiparous sows (gilt progeny; GP) have lower birth, weaning and slaughter weights than sow progeny (SP). GP also have reduced gastrointestinal tract (GIT) development, as evidenced by lower organ weights. Therefore, the aim of this experiment was to quantify changes in GIT barrier function that occur in birth and weaning, representing two major challenges to the young piglet. The effects of parity (GP vs. SP) in GIT barrier integrity function were quantified at four timepoints: birth (~0 h), 24 h after birth (24 h), 1-d preweaning (PrW), and 1-d postweaning (PoW) in commercially reared piglets. Due to inherent differences between newborn and weanling pigs, the results were analyzed in two cohorts, birth (0 vs. 24 h, n = 31) and weaning (PrW vs. PoW, n = 40). Samples of the stomach, jejunum, ileum, and colon were excised after euthanasia and barrier integrity was quantified by measuring transepithelial resistance (TER), macromolecular permeability, the abundance of inflammatory proteins (IL-8, IL-1ß, and TNF-α) and tight junction proteins (claudin-2 and -3). Papp was characterized using a dual tracer approach comprising 4 KDa fluorescein isothiocyanate (FD4) and 150 kDa tetramethyl rhodamine isothiocyanate (T150)-labeled dextrans. Characteristic effects of the initiation of feeding and weaning were observed on the GIT with the initiation of feeding, such as increasing TER and reducing Papp at 24 h, consistent with mucosal growth (P = 0.058) This was accompanied by increased cytokine abundance as evidenced by elevations in TNF-α and IL-1ß. However, GP had increased IL-8 abundance (P = 0.011 and 0.063 for jejunum and ileum respectively) at birth than 24 h overall. In the weaning cohort, jejunal and ileal permeability to FD4 was higher in GP (P = 0.05 and 0.022, respectively) while only higher ileal T150 was observed in GP (P = 0.032). Ileal claudin-2 abundance tended to be higher in SP overall (P = 0.063), but GP ileal claudin-2 expression was upregulated weaning while no change was observed in SP (P = 0.043). Finally, other than a higher jejunal TNF-α abundance observed in SP (P = 0.016), no other effect of parity was observed on inflammatory markers in the weaning cohort. The results from this study indicate that the GIT of GP have poorer adaptation to early life events, with the response to weaning, being more challenging which is likely to contribute to poorer postweaning growth.

The progeny of primiparous sows (gilt progeny; GP) have poorer lifetime growth performance in comparison to progeny from multiparous sows (sow progeny; SP). Previous research suggests that there is an underlying biological basis for reduced growth performance which is attributed to differences in gastrointestinal tract (GIT) barrier development during early life. This study aimed to clarify the timeframes of when these differences are in effect by investigating GIT development during two major events of a piglet's life: birth and weaning. To do this, GIT tissue was collected from GP and SP at four time points; birth, 24 h after birth, 1-d preweaning, and 1-d postweaning and assessed for functional development. The main findings from this study indicate there are early signs of variation in GIT development within the first 24 h of life between GP and SP, and that these differences increase through the preweaning period, with GP entering weaning with poorer GIT development and function. Possible explanations for the reduced GI development may be reduced maternal nutrition during the suckling period.

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Pubertal genetic variations between the indigenous Chinese Wanyue Black pig breed and the imported Yorkshire breed significantly impact their reproductive capacity. In order to identify the differentially expressed genes, gene networks, and metabolic pathways in ovary transcriptome of gilts, the serum hormone levels were analyzed by ELISA, and RNA-seq was performed to analyze ovarian genes. Our results reveal higher estradiol (E2) levels in Wanyue black gilts compared to Yorkshire gilts, while Yorkshire gilts exhibit elevated progesterone (P4) and GnRH levels. We identified a total of 154 differentially expressed genes (DEGs), with 87 up-regulated and 67 down-regulated genes in the Wanyue black gilts ovaries compared to the Yorkshire gilts. GO enrichment analysis unveiled the participation of DEGs in processes such as "Reproduction", "Reproductive system development", and "Ovarian follicle development". Moreover, KEGG enrichment analysis revealed the involvement of DEGs in multiple signaling pathways associated with hormone biosynthesis and puberty, encompassing "Steroid hormone biosynthesis", "Estrogen signaling pathway", and "Prolactin signaling pathway". The subsequent bioinformatics analysis identified nine functional genes that potentially contribute to the disparity in ovaries between Wanyue black gilts and Yorkshire gilts. This study offers significant insights into the endocrine and genetic aspects of pubertal development in gilts.

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The current study investigated effects of dietary amino acid (AA) availability on lactational body condition loss and metabolic status, in relation to reproductive parameters after weaning up to Day 8 post-ovulation. Primiparous sows (n = 35) were allocated to one of two lactation diets containing either low crude protein (CP, 140 g/kg) with a low percentage (8%) of slow protein in total protein (LL, n = 18) or high CP (180 g/kg) with a high (16%) percentage of slow protein (HH, n = 17). The HH diet was expected to improve AA utilization by supplying more AA, in a more gradual fashion. The diets did not affect sow body condition loss during lactation, while the HH diet tended to increase litter weight gain during the week 3 of lactation (Δ = 1.3 kg, P = 0.09). On Day 14 post-farrowing, HH diet led to higher plasma urea both pre-feeding and post-feeding (Δ = 2.3 mmol/L, P < 0.01, Δ = 2.4 mmol/L, P < 0.01, respectively), whilst plasma creatinine, NEFA and IGF-1 were similar. No dietary effects on reproductive parameters were found, however several relationships were found between body condition and reproductive parameters. Sows with higher body weight on Day 1 or Day 21 post-farrowing had greater follicle size on Day 3 post-weaning (ß = 0.03 mm/kg, P < 0.01, ß = 0.04 mm/kg, P < 0.01, respectively). At Day 8 post-ovulation, plasma progesterone concentration was negatively related to loin muscle loss (ß = -0.67 ng/ml · mm-1, P = 0.02), backfat loss (ß = -2.33 ng/ml · mm-1, P = 0.02), and estimated body fat loss (ß = -0.67 ng/ml · mm-1, P = 0.02). Both plasma progesterone and the number of corpora lutea were positively related to the energy balance during lactation (ß = 0.03 ng/ml · ME MJ-1, P = 0.01, ß = 0.01 CL/ME MJ, P = 0.02, respectively). The conceptus size at Day 8 post-ovulation was negatively related to body weight loss (ß = -0.01 mm/kg, P = 0.01), estimated body fat loss (ß = -0.02 mm/kg, P = 0.03) and estimated body protein loss (ß = -0.06 mm/kg, P = 0.04), and was positively related to the energy balance during lactation (ß = 5.2*10-4 mm/ME MJ, P = 0.01). In conclusion, body protein and fat losses during lactation reduced subsequent plasma progesterone concentration and conceptus development at Day 8 post-ovulation.

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Gene-edited mosquitoes lacking a gamma-interferon-inducible lysosomal thiol reductase-like protein, namely (mosGILTnull) have lower Plasmodium infection, which is linked to impaired ovarian development and immune activation. The transcriptome of mosGILTnull Anopheles gambiae was therefore compared to wild type (WT) mosquitoes by RNA-sequencing to delineate mosGILT-dependent pathways. Compared to WT mosquitoes, mosGILTnull A. gambiae demonstrated altered expression of genes related to oogenesis, 20-hydroxyecdysone synthesis, as well as immune-related genes. Serendipitously, the zero population growth gene, zpg, an essential regulator of germ cell development was found to be one of the most downregulated genes in mosGILTnull mosquitoes. These results provide a crucial missing link between two previous studies on the role of zpg and mosGILT in ovarian development. This study further demonstrates that mosGILT has the potential to serve as a target for the biological control of mosquito vectors and to influence the Plasmodium life cycle within the vector.

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Breeding herds in the US are trending toward eradication of Mycoplasma hyopneumoniae (M. hyopneumoniae) due to the positive impact on welfare and downstream production. In an eradication program, "Day 0″ is the time point when the last replacement gilts to enter the herd were exposed to M. hyopneumoniae and marks the beginning of a herd closure. However, no specific diagnostic protocols are available for confirmation of successful exposure to define Day 0. Therefore, the objective of this study was to develop diagnostic guidelines, including sample collection approaches, for two common gilt exposure methods to confirm an entire population has been infected with M. hyopneumoniae following purposeful exposure. Forty gilts, age 21-56 days, were ear-tagged for longitudinal sample collection at five commercial gilt developer units (GDUs) and were exposed to M. hyopneumoniae by natural contact or aerosolization. Study gilts originated from sources known to be negative to major swine pathogens, including M. hyopneumoniae, and were sampled prior to exposure to confirm negative status, then every two weeks. Blood samples were collected for antibody detection, while laryngeal and deep tracheal secretions and pen based oral fluids were collected for PCR, and sampling continued until at least 85% of samples were positive by PCR. Detection of M. hyopneumoniae varied greatly based on sample type. Oral fluids showed the lowest detection in groups of gilts detected positive by other sample types. Detection by PCR in deep tracheal secretions was higher than in laryngeal secretions. Seroconversion to and PCR detection of M. hyopneumoniae on oral fluids were delayed compared to PCR detection at the individual level. By two weeks post-exposure, at least 85% of study gilts in three GDUs exposed by aerosolization were PCR positive in deep tracheal secretions. Natural contact exposure resulted in 22.5% of study gilts becoming PCR positive by two weeks post-initial exposure, 61.5% at four weeks, and 100% at six weeks on deep tracheal secretions. Deep tracheal secretions required the lowest number of gilts to sample for the earliest detection compared to all other samples evaluated. As observed in one of the GDUs using aerosolization, demonstration of failure to expose gilts to M. hyopneumoniae allowed for early intervention in the exposure protocol and delay of Day 0, for accurate timing of the eradication protocol. Sampling guidelines proposed in this study can be used for verification of M. hyopneumoniae infection of gilts following exposure to determine Day 0 of herd closure.

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The rearing of large litters from hyperprolific sows is a characteristic of modern genotypes. However, these sows have body and reproductive characteristics that differentiate them from the genotypes of the past decades, making it necessary to adopt different management strategies. This review describes the main care and challenges associated with the hyperprolificity of sows during the period in which replacement gilts are selected, along with gestation, parturition, lactation, and the weaning-estrus interval. It describes the challenges that these sows' piglets will face during the lactation period and includes some strategies adopted to develop these surplus piglets. In addition, it identifies areas where more research is needed to understand the reproductive management of modern genotypes.

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Background and Aim: Porcine epidemic diarrhea (PED) is a severe infectious disease that causes very high mortality in newborn piglets up to 2-3 weeks age. The main cause of repeated outbreaks of PED in infected farms is the continuing circulation of the PED virus (PEDV). Improper gilt management, including inappropriate gut feedback, commingling, and inadequate immunization, causes a prolonged virus circulation in breeding herds. Moreover, insufficient transfer of passive immunity through the colostrum to newborn piglets can also increase infection risk. Therefore, a gilt management program that controls infection should focus on infection monitoring and acclimatization. We investigated the source of recurrent PEDV outbreaks and examined how the effect of immunization methods, specifically using gut feedback mechanism and vaccination, can reduce PEDV circulation and improve immune responses in replacement gilts. Materials and Methods: The study site was a segregated commercial production farm with endemic PEDV. The acclimatization methods included gut feedback and vaccination. This longitudinal study evaluated two strategies of gilt acclimatization against PEDV: Program 1 (routine farm management) and Program 2 (early feedback program and all-in-all-out system). Levels of PED RNA in fecal samples were measured using quantitative reverse transcription-polymerase chain reaction, and the PEDV S gene was sequenced. Porcine epidemic diarrhea-specific immune responses were assessed using enzyme-linked immunosorbent assay and the serum neutralization test. Results: Porcine epidemic diarrhea outbreaks occurred in the farrowing, nursery, and finishing units and farrowed litters 5-10 days old were symptomatic of PED. Phylogenetic analyses of the S gene showed PEDV sequence divergence between PEDV field strains and vaccine strain, which may contribute to periodic outbreaks and continued persistence of PEDV in the farm. After gut feedback and acclimatization, replacement gilts from Program 1 continued to shed PEDV before being introduced to sow herds, while those from Program 2 did not shed PEDV before being introduced to sow herds. However, the components of the immune response against PEDV in serum samples, including specific immunoglobulin (Ig)G, specific IgA, and neutralizing antibodies were lower in gilts of Program 2 than those in Program 1. Conclusion: We speculate that implementing the appropriate gilt acclimatization program can control PEDV circulation in farm. However, the acclimatization methods in Program 2 did not induce a strong and adequate immune response in replacement gilts. Therefore, maternal immunity levels and the degree of protection against PEDV require further study.

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Porcine Circovirus type 2 (PCV2) vaccination of gilts during acclimation has become a routine practice in commercial pig farms to homogenize herd immunity to PCV2 and reduce the impact of diseases associated with PCV2 infection, namely reproductive, respiratory, systemic, and other PCV2-associated diseases. The periodic mass vaccination of sows, with the same objectives, is also common. To ensure mass vaccination is an appropriate health management tool, demonstrating that the vaccine is safe in different sow/gilt physiological stages is necessary. The objective of the present studies was to evaluate safety of a PCV2a/PCV2b/Mycoplasma hyopneumoniae (PCV2a2bMHP) killed vaccine in sows and gilts during gestation and lactation, under controlled experimental pen conditions, and during gestation, mimicking mass vaccination, under field conditions. Safety was assessed by monitoring for immediate adverse reactions after vaccination, rectal temperatures after vaccination (controlled experimental pen studies only), local and systemic reactions, and reproductive performance (studies conducted during pregnancy) or lactation performance (studies conducted during lactation). In total, 416 sows/gilts were enrolled, and more than 4000 piglets were observed during their first week of life, under field conditions. In both controlled experimental and field studies, no immediate anaphylactic type reactions were observed after vaccination and the incidence of adverse events, such as depression or decreased appetite, was acceptable for what is expected in a swine herd. In the studies conducted during gestation, vaccination did not significantly increase rectal temperature of the vaccinated animals. Sow reproductive outcomes were not affected by vaccination. The farrowing rate of animals participating in the field study was higher than the historic averages of the farms. In the laboratory studies conducted during the first and second half of gestation, no differences in reproductive outcome were observed between vaccinated and non-vaccinated animals. However, sows vaccinated during lactation experienced a transient hyperthermia which did not affect milk production since the piglets' average daily weight gain was not affected. The previously described results confirm that the administration of a PCV2a2bMHP vaccine was safe in the tested conditions. All the anticipated benefits of sow and gilt PCV2 vaccination, such as homogenization of PCV2 antibody titers or reduction in PCV2 circulation in the herd, would not be masked by potential adverse events due to herd vaccination. In conclusion, the administration of a PCV2a2bMHP vaccine to sows and gilts during different stages of gestation and during lactation is safe.

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Low colostrum intake relates to poorer health and infertility in swine. We previously connected vaginal lipid profiles at weaning to fertility of sows. We hypothesized vaginal lipidome varied with colostrum intake. Our objective was to determine whether indicators of colostrum intake, immunocrit (IM) and weight gain 24 h postnatal (PN), related to vaginal lipids at d21 PN. Gilts (n=60) were weighed and blood sampled to measure IM. On d21 PN vaginal swabs were taken and lipids measured using multiple reaction monitoring. Abundance of multiple lipids differed (P<0.05) between gilts categorized as high versus low IM and high versus low 24 h gain. The abundance of multiple lipids correlated with IM and 24 h gain. Phosphatidylcholine PC(36:3), PC(36:2), and arachidonic acid (C20:4) positively (P<0.05) correlated with IM. The ether lipid PCo(38:6) and multiple cholesteryl esters negatively (P<0.05) correlated with IM. ROC analysis indicated arachidonic acid and docosanoic acid (C22:0) may serve as excellent biomarkers that distinguish between high and low IM. Similar to gilts found to be infertile, lipid profiles of low colostrum intake animals had greater abundance of very long chain fatty acids, lipids with high levels of unsaturation, and cholesteryl esters, which are metabolized in peroxisomes indicating their potential dysfunction.

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Introduction: Porcine circovirus type 2 (PCV2) is the primary etiological agent of porcine circovirus diseases (PCVD), which are widespread in most pig herds, causing huge economic losses in the global pig industry. Therefore, it is critical to assess the infection characteristics of PCV2 in different swine herds to develop effective strategies against PCVD. Methods: In this study, routine diagnostic and monitoring protocols were used to collect 12,714 samples from intensive farms in China, and PCV2 was tested for by qPCR to determine positivity rates and viral loads in samples from different herds and materials. Results: PCV2 was found to be prevalent throughout China, and fattening farms had higher positivity rates than breeding farms. The PCV2 positivity rates in breeding farms in Southern China were higher than those in Northern China. Growing-finishing pigs demonstrated the highest positivity rate in the tested samples, while pre-weaning piglets and adult sows had the lowest. Meanwhile, samples with viral loads exceeding 106 copies/mL in growing-finishing pigs had 27.2% positivity, compared to 1.9% and 3.3% in sows and piglets, respectively. The results of the viral loads in the serum samples followed a similar trend. Discussion: The findings reveal that PCV2 circulates in different herds from intensive farms, with positivity increasing from pre-weaning to growing-finishing herds. It is urgent to develop effective strategies to reduce PCV2 positivity in growing-finishing herds and prevent viral circulation among pigs.

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Swine disease elimination programs for Mycoplasma hyopneumoniae are commonly applied in the North American swine industry and may include the aerosolization of medium containing lung tissue to achieve population exposure prior to start. Field data has indicated M. hyopneumoniae PCR detection in pigs beyond 240 days post-herd closure (dphc; planned end of an elimination program) and is thought to contribute to disease elimination programs' failure. Here, the duration of M. hyopneumoniae detection in sows and replacement gilts following aerosolized lung homogenate exposure, as part of a dual disease elimination program, was determined. A subset of sows and gilts from a commercial sow herd and off-site gilt development unit were longitudinally sampled to collect deep tracheal catheter secretions at various times post-exposure. Samples were tested for M. hyopneumoniae using a species-specific real-time PCR. A proportion of 58, 51, 52, 19, and 2% females were detected positive at 30, 60, 120, 180 and 240 dphc, respectively. Noteworthy, a greater proportion of gilts exposed at the off-site GDU were detected PCR positive for M. hyopneumoniae at each sampling event, compared to sows. In this study, assaying for genetic material in live female pigs showed extended detection of M. hyopneumoniae until at least 240 dphc. This data suggests persistence of M. hyopneumoniae longer than previously reported and highlights the importance of performing diagnostic testing to confirm negativity to the bacterium, prior to opening sow herds, especially late in the herd closure timeline.

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Currently, pigs breed in Korea are LYD (Landrace × Yorkshire × Duroc) crossbred pigs. Pigs used as fresh meat are gilts and barrows. However, the current supply of pork is not satisfying Korean consumers. In addition, the comparison of carcasses between gilts and barrows only studies carcass weight, backfat thickness, or meat quality, and there are very few studies comparing carcass characteristics. The purpose of this study was to compare characteristics of 7 primal cuts of gilts and barrows as measured by AutoFom III. A total of 350,179 pigs were used, including 176,461 gilts and 173,718 barrows. Characteristics of seven primal cuts were measured using AutoFom III. In the case of carcass weight, there was no significant difference in grade 1+. For all other survey items except for grade 2, gilts showed significantly (p < 0.05) higher values. For all grades except for pork belly, amounts of the remaining six primal cuts were higher in gilts (all p < 0.05,). In addition, the ratio of intermuscular fat in the pork belly of barrows showed a higher value than that in the pork belly of gilts (p < 0.05). The amount of pork belly, which is the most popular among consumers in Korea, not only produced more production than gilts in barrows, but also showed a higher value than gilts in barrows for the ratio of intermuscular fat affecting taste. In summary, gilts produced higher yields than barrows in all parts except pork belly. For the production of only pork belly, barrows showed higher production than gilts.

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Background and Aim: Gilt selection has the propensity to improve reproductive performance and promote longevity. However, the impact of this process on oxidative stress biomarker levels remains to be unraveled under tropical conditions. This study aimed to determine the effect of management processes during gilt selection on serum malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD) levels, and the performance of replacement gilts under tropical environmental conditions. Materials and Methods: Two groups of 90 crossbred gilts (mean age: 9.72 ± 0.097 weeks) were selected 2 weeks apart, allotted to six pens of 30, and raised in an open barn with shaded roofs. Following their respective entry weeks, gilts in groups one and two were subjected separately to three subsequent selection processes (involving movements, handling, and examination of structural and reproductive traits) at weeks 12, 17, and 24 in the replacement barn. Grower, finisher, and gestation diets were supplied ad libitum for 25 weeks. Environmental temperature (°C), humidity (%), and light (lux) were recorded. Malondialdehyde, CAT, and SOD levels were assayed using blood samples collected on day 1 of experiment (PRE), and at week 24 in replacement barn (POST). Results: Feed intake, weight gain, and percent selected at week 24 were 1.89 versus 1.90 kg/day, 0.81 versus 0.76 kg/day, and 75.23% versus 64.45% for groups one and two, respectively. Sickness, death, slow growth, leg, and reproductive problems caused 24.76% versus 35.55% of removals in groups one and two, respectively. Serum biomarkers were insignificant at PRE but were elevated at POST, with mean values of 14.25 versus 13.84 uM, 5.10 versus 3.26 nmol/min/mL, and p < 0.05, and 1.13 versus 1.68 U/mL and p < 0.05 for MDA, CAT, and SOD in groups one and two, respectively. Conclusion: The impact of the selection process was meager compared to the adverse effect of high environmental temperatures. The management and selection of replacement gilts in an uncontrolled environmental temperature increase the risk of oxidative stress, especially in tropical regions.

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The objective of the present study was to evaluate the efficacy of a porcine circovirus type 2 (PCV2) double vaccination in weaning piglets reared for gilts under field conditions. The study was conducted at a Greek farrow-to-finish conventional pig farm with a previous history of PCV2 infections. The trial included 96 female piglets at 21 days of age, which were equally allocated to two different study groups. Piglets of the group-1 received a single PCV2 vaccination at 21 days of age, while piglets of the group-2 were double vaccinated against PCV2, at 21 and 42 days of age. The results indicated that the piglets of group-2 had better growth performance, as they showed higher body weight (BW) and average daily weight gain (ADWG). In addition, ELISA tests showed that the double- vaccinated piglets presented a better humoral response against PCV2, as higher levels of IgG antibodies were detected in them than the piglets of the group-1. In conclusion, the current results suggested that a double PCV2 vaccination of piglets, reared for gilts, on a PCV2-affected farm could lead to higher protection against the virus.

RESUMEN

Our previous study found dietary konjac flour (KF) supplementation could improve insulin sensitivity and reproductive performance of sows, but its high price limits its application in actual production. This study aimed to investigate the effects of supplementation of a cheaper combined dietary fiber (CDF, using bamboo shoots fiber and alginate fiber to partially replace KF) from the last 50 days of gestation to parturition on farrowing performance, insulin sensitivity, gut microbiota, and placental function of gilts. Specifically, a total of 135 pregnant gilts with a similar farrowing time were blocked by backfat thickness and body weight on day 65 of gestation (G65d) and assigned to 1 of the 3 dietary treatment groups (n = 45 per group): basal diet (CON), basal diet supplemented with 2% KF or 2% CDF (CDF containing 15% KF, 60% bamboo shoots fiber, and 25% alginate fiber), respectively. The litter performance, insulin sensitivity and glucose tolerance parameters, placental vessel density, and short-chain fatty acids (SCFAs) levels in feces were assessed. The gut microbiota population in gilts during gestation was also assessed by 16S rDNA gene sequencing. Compared with CON, both KF and CDF treatments not only increased the piglet birth weight (P < 0.05) and piglet vitality (P < 0.01) but also decreased the proportion of piglets with birth weight ≤ 1.2 kg (P < 0.01) and increased the proportion of piglets with birth weight ≥ 1.5 kg (P < 0.01). In addition, KF or CDF supplementation reduced fasting blood insulin level (P < 0.05), homeostasis model assessment-insulin resistance (P < 0.05), serum hemoglobin A1c (P < 0.05), and the level of advanced glycation end products (P < 0.05) at G110d, and increased the placental vascular density (P < 0.05) at farrowing. Meanwhile, KF or CDF supplementation increased microbial diversity (P < 0.05) and SCFAs levels (P < 0.05) in feces at G110d. Notably, the production cost per live-born piglet was lower in CDF group (¥ 36.1) than KF group (¥ 41.3). Overall, KF or CDF supplementation from G65d to farrowing could improve the farrowing performance of gilts possibly by improving insulin sensitivity, regulating gut microbiota and metabolites, and increasing placental vascular density, with higher economic benefits and a similar effect for CDF vs. KF, suggesting the potential of CDF as a cheaper alternative to KF in actual production.

Dietary konjac flour (KF) supplementation could improve insulin sensitivity and reproductive performance of sows, but its high price limits its application in actual production. This study investigated the impact of 2% konjac flour (KF) and 2% combined dietary fiber (CDF, containing 15% KF, 60% bamboo shoots fiber, and 25% alginate fiber) supplementation from the last 50 days of gestation to farrowing on farrowing performance, placental function, insulin sensitivity, and gut microbiota of gilts. Results indicated that KF or CDF supplementation during this time could improve the farrowing performance of gilts possibly by improving insulin sensitivity and gut microbiota, and increasing placental vascular density. Meanwhile, CDF could lower the production cost per live-born piglet and have a similar effect to KF, thus a cheaper alternative to KF in actual production. This study facilitates understanding the beneficial effects of KF and non-conventional dietary fiber sources on the reproductive performance of gilts.

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