Causes, consequences and biomarkers of stress in swine: an update

Needle-Free Targeted Injections Using Bubble Laser Technology in Therapeutics

This work explores bubble laser technology as an alternative to needles in injection systems for vaccination, cancer treatment, insulin delivery, and catheter hygiene. The technology leverages laser-induced microfiltration and bubble dynamics to create high-speed pneumatic jets that penetrate the skin without needles, addressing discomfort, infection risk, and needle-related concerns. The system's performance is analyzed based on laser wavelength, pulse duration, and Gaussian beam droplet size. The findings indicate a significant increase in spot size at 1064 nm compared with 400 nm, consistent with the diffraction theory. Induced bubble dynamics reveal bubble generation, jetting, and fluid interactions as the Weber number increases, as well as jet velocity and fluid inertia. For femtosecond pulses, increasing the pulse duration from 100 to 1500 fs reduces the bubble lifespan from 0.8 to 0.3 arbitrary units, and the collapse pressure decreases from 2.1 to 0.4 bar. For picosecond pulses, the bubble lifetime decreases from 0.9 to 0.5 arbitrary units, and the pressure drop decreases from 2.0 to 0.4 bar as the pulse length extends from 2000 to 8000 ps. Jet formation in laser jet injection systems is enhanced by short pulses in water that produce longer-lasting bubbles. Drug delivery based on the Rayleigh-Plesset equation is characterized by a low-pressure collapse and short bubble lifetime. Thus, this relationship suggests that bubble laser technology can provide a more controlled and safer method of needle-free procedures, increasing compliance and reducing tissue trauma.

Proteomics analysis for key molecules in adrenal glands of Wenchang chickens for their resistance to heat stress

Rising temperatures and intensified agricultural practices have heightened heat stress (HS)-related challenges in poultry farming, notably heat-induced sudden death in chickens. Wenchang chickens, recognized for their heat resistance, have emerged as the potential candidates for improving the economic efficiency of poultry farming. The adrenal gland plays a crucial role in preventing HS-induced heart failure sudden death by secreting hormones. However, little is known about the damage to and resilience of Wenchang chicken adrenal glands during HS. In this study, 34 healthy Wenchang chickens with similar weights were selected for formal experimentation, with 10 as the control group (Con). Following a single exposure to acute HS of 42 ± 1°C and 65% relative humidity for 5 h, 15 deceased individuals formed the HS death (HSD) group, and 9 survived comprised the HS survival (HSS) group. ELISA revealed significant higher (P < 0.05) levels of COR and NE in the HSS and the lowest levels of CORT and EPI in the HSD. Histopathological analysis indicated major degeneration in HSS cortical and chromaffin cells and extensive cell necrosis (nuclear pyknosis) in HSD. Proteomic analysis identified 572 DEPs in HSD vs. Con and 191 DEPs in HSS vs. Con. Bioinformatics highlighted ER protein processing, especially ERAD as a key pathway for heat stress resistance (HSR) in the adrenal gland, with HSPH1, DNAJA1, HSP90AA1, HSPA8 and HERPUD1 identified as regulating key molecules. Western blotting validated significantly higher (P < 0.01) protein levels in both HSS and HSD compared to the Con. Immunohistochemical staining showed increased cytoplasmic HSPH1-positive signal intensity under HS and enhanced HSP90AA1 nuclear signals, strongest in HSS. In summary, HS induces pathological damage in Wenchang chicken adrenal glands, affecting hormone secretion, and various heat shock proteins play crucial roles in cellular resistance. These results elucidate the biological basis of HSR in Wenchang chickens from the perspective of the adrenal gland and provide necessary research foundations for enhancing economic performance of various broilers in high-heat environments and screening drugs for HS treatment.

Physiology, gene expression, and behavior as potential indicators of oxidative stress in piglets

The goal of the current study was to develop a pig model to investigate oxidative stress with a low negative impact on piglet welfare. Four independent trials (A, B, C, and D) were performed using a single intraperitoneal shot of lipopolysaccharide (LPS) as an immune challenge, aiming to assess the minimal LPS dose for piglets of different age to trigger a measurable acute oxidative stress response in healthy animals. In trial A, piglets received an LPS dose of 25 µg/KgBW at 41 days post-weaning (p.w.). In trial B, piglets received 25 µg/KgBW of LPS at 28 days p.w., in trials C And D, piglets were injected with 50 µg/KgBW of LPS at 21 days p.w., respectively. Piglets were randomly allocated either to the T1) Control group with saline solution (Ctrl), or T2) LPS challenge (LPS). The oxidative stress response was measured through the enzymatic activity of glutathione peroxidase (GPx), glutathione-S-transferase (GST), superoxide dismutase (SOD), and catalase (CAT), in both plasma and intestinal tissues. Intestinal gene expression of oxidative stress and inflammatory markers was assessed. Discomfort behaviors (panting, prostration, trembling, and vomits) were also recorded. Plasmatic and intestinal oxidative stress response was inconsistent across the four trials even when the dose and pig age were similar, possibly due to individual variability. Relative gene expression differences of anti-inflammatory cytokines (IL10), oxidation precursor (iNOS), and antioxidant markers (GPx4, MnSOD, and CAT) were detected between Ctrl and LPS treatment (P < 0.05) when assessed. Behavioral observations were sensitive to the LPS dose relative to Ctrl (P < 0.05) in all four trials. These results suggest that behavioral observations can be used as a non-invasive methodology to detect the presence of oxidative stress in pigs in challenging conditions. Behavioral observations were more sensitive than other indicators (i.e., biomarkers and gene expression) in the current study. However, a sensitivity scale system needs to be developed to qualify and rank the impact of oxidative stress in pigs.

Dietary curcumin supplementation attenuates hepatic damage and function abnormality in a chronic corticosterone-induced stress model in broilers

Chronic stress refers to the activation of the hypothalamic-pituitary-adrenal (HPA) axis and elevated blood contents of ACTH and corticosterone (CORT), exhibiting significant adverse effects on health outcomes. Currently, natural polyphenol compounds are increasingly being explored as potential therapeutic agents and have been considered as a treatment option for a variety of stress-induced diseases. Curcumin (CUR) is the main substance in Curcuma longa (Zingiberacea) rhizome that has strong health-beneficial properties. The study aimed to assess the potential protective effects of CUR on hepatic oxidative stress damage and abnormal lipid deposition in a chronic CORT-induced stress (CCIS) model in broilers. One hundred and twenty experimental broilers were randomly divided into 1) control group (CON), 2) CUR group (200 mg/kg feed), 3) CORT group (4 mg/kg BW CORT) and 4) CORT+CUR group (200 mg/kg feed plus 4 mg/kg BW CORT). The liver histology, glycolipid metabolism and oxidative stress were determined. In addition, qPCR was performed to identify shifts in genes expression. Compared with CON group, broilers under CCIS showed a decreased body weight, body weight gain and average daily gain, while dietary CUR significantly reversed these adverse effects. Furthermore, the plasma contents of TCH, TG, HDL-C, LDL-C, TP, GLB and AST were all significantly increased in CCIS broilers, while dietary CUR obviously alleviated the increase of TCH, HDL-C, LDL-C and AST, and relieved the hepatic lipid deposition disorder and liver injury. Moreover, CCIS significantly increased the contents of MDA in both liver and plasma, and decreased the content of plasma SOD, while CUR obviously reversed these changes, showing reduced oxidative stress damage. Finally, the mRNA expressions of FAS, ACC, SCD and the protein level of PPAR-γ were significantly increased, meanwhile the mRNA expression of lipolytic genes ACOX1, ATGL and CPT as well as two major intracellular antioxidant enzymes SOD1 and GPX1 were obviously decreased, while CUR effectively reversed these effects. These results showed that dietary CUR effectively alleviated CCIS-induced body weight loss, hepatic oxidative damage and lipid deposition disorder, suggesting the possible therapeutic effectiveness of CUR against hepatic damage and function abnormality caused by CCIS.

Clicker Training in Minipigs to Reduce Stress during Blood Collection-An Example of Applied Refinement

Pigs (and minipigs) are often restrained with a maxillary sling for blood collection. They mainly produce strong vocalisations and show resistance to the procedure, which subjectively appears to be stressful for the animals. The present study investigated whether minipigs can be trained to tolerate aversive stimuli and whether training can reduce stress during blood collection. Blood was taken from 12 Ellegaard minipigs with fixation; thereafter, the animals were trained for 3 weeks using clicker training. Then, blood was taken again, but without fixation. Before and after each blood sample, saliva samples were taken. The cortisol concentration was determined using ELISAs. Serum cortisol was not significantly different before and after training (paired-sample t-test, t (9) = 2.052, p = 0.07). However, salivary cortisol was significantly lower after training (ANOVA (analysis of variance), p-value < 0.001, F-value 6.181). In addition, trained minipigs showed a significantly lower heart rate after blood sampling (paired-sample t-test, t (11) = 4.678, p = 0.001) as well as significantly lower heart rate variability (t (11) = 3.704, p = 0.003) compared to before training. The minipigs could be trained to tolerate aversive stimuli. This contributed to stress reduction when taking blood samples.

Effect of Group Mixing and Available Space on Performance, Feeding Behavior, and Fecal Microbiota Composition during the Growth Period of Pigs

Stress significantly affects the health, welfare, and productivity of farm animals. We performed a longitudinal study to evaluate stress's effects on pig performance, feeding behavior, and fecal microbiota composition. This study involved 64 Duroc pigs during the fattening period, divided into two experimental groups: a stress group (n = 32) and a control group (n = 32). Stressed groups had less space and were mixed twice during the experiment. We monitored body weight, feed efficiency, feeding behavior, and fecal microbiota composition. Compared to the control group, the stressed pigs exhibited reduced body weight, feed efficiency, fewer feeder visits, and longer meal durations. In the fecal microbiota, resilience was observed, with greater differences between groups when sampling was closer to the stressful stimulus. Stressed pigs showed an increase in opportunistic bacteria, such as Streptococcus, Treponema and members of the Erysipelotrichaceae family, while control pigs had more butyrate- and propionate-producing genera like Anaerobutyricum, Coprococcus and HUN007. Our findings confirm that prolonged stress negatively impacts porcine welfare, behavior, and performance, and alters their gut microbiota. Specific microorganisms identified could serve as non-invasive biomarkers for stress, potentially informing both animal welfare and similar gut-brain axis mechanisms relevant to human research.

Faecal Glucocorticoid Metabolites and Hair Cortisone/Cortisol Measurements in Domestic Pigs Exposed to Road Transportation and Dexamethasone Treatment

Pig homeostasis is challenged by stressful production practices, like road transportation. Glucocorticoids (GCs) are mediators of reactive homeostasis, and their concentrations are frequently used as a stress indicator. The adrenocortical activity of fattening female and castrated male pigs was monitored over a 5-day longitudinal study. A bi-factorial experimental design was applied on day 2; 18 pigs in pen 1 were transported for 3 h (T; 1.2 m2/pig), and 18 pigs were kept in pen 2 (NT). Ten pigs from each pen were treated with dexamethasone (T-D or NT-D), and eight with saline solution (T-SS or NT-SS). Adrenocortical activity was assessed by measuring the levels of faecal glucocorticoid metabolites (FGMs) and hair cortisol and cortisone. In T-SS pigs, the level of FGMs was higher after transportation than in NT-SS pigs. The level of FGMs of T-D pigs initially increased but then reached similar levels to those of NT-SS sooner than T-SS. In contrast, hair cortisol and cortisone did not respond to the treatments. Nevertheless, the hair cortisone/cortisol ratio increased due to transport and decreased after dexamethasone administration. Daily faecal sampling proved still more reliable than 60-day hair sampling for assessing adrenocortical activity. Transported pigs recovered their adrenocortical baseline levels within 24 h. Dexamethasone attenuated the response to transport.

Simultaneous Use of Iron/Anticoccidial Treatment and Vaccination against Oedema Disease: Impact on the Development of Serum-Neutralising Antibodies, Hematinic and Anticoccidial Activities in Piglets

Oedema disease (OD) in weaned piglets is caused by shigatoxigenic Escherichia coli (STEC), which produces the Stx2e toxin. The disease is controlled by early vaccination (for example, with Ecoporc Shiga®). Iron-deficiency anaemia (IDA) and cystoisosporosis are the most common clinical conditions in piglets. These conditions are managed mainly by the intramuscular injection of iron and application of toltrazuril (for example, Forceris®). In the present study, we sought to evaluate any effect on the efficacy of OD vaccination and iron/anticoccidial treatment resulting from a simultaneous application. An evaluation was carried out by measuring the development of neutralising antibodies against the Stx2e toxin, hematinic indices and oocysts shedding. Six litters from Stx2e-antibody-negative sows were included in the study, with 12 piglets in each litter. The piglets were randomly allocated into two groups on their second day of life (DOL): (T1) iron/anticoccidial treatment and vaccine were administered on different days, and (T2) products were administered simultaneously. Blood samples were collected to determine the levels of serum-neutralising antibodies, haemoglobin and haematocrit. Faecal matter was examined for the presence of oocysts of Cystoisospora suis. No differences were found between the two groups in terms of the development of neutralising antibodies. The levels of haemoglobin and haematocrit were lower (p < 0.05 and p = 0.08, respectively) when iron/anticoccidial treatment and vaccine were applied simultaneously but within the optimal range, based on current interpretive criteria for IDA. Oocysts were not detected in the faecal samples from the animals in either group. In conclusion, we found that, under the conditions of our study, the efficacy of OD vaccination and iron/anticoccidial treatment was not affected by the simultaneous use.

Evaluation of a scheme to identify risks for tail biting in pigs

The study aimed to assess the effectiveness of a tail-biting risk assessment scheme. The scheme consisted of trained private veterinary practitioners (assessors) applying a risk assessment tool on commercial pig farms to six pens per farm. The assessment tool included animal and non-animal-based observations which were used to determine the perceived risk of tail biting for each pen. For this study 27 farms were assessed, and a subsequent batch of pigs from each farm underwent post-mortem tail lesion scoring at the abattoir. The assessments revealed that a high percentage of pens had fully slatted flooring (92%) and mixed-sex populations (84%), with a significant proportion of pens containing pigs which were all tail docked (92%). Most pens (86%) did not allow all pigs simultaneous access to feeders. Enrichment was present in 88% of the pens, but most (46%) were supplied with only one item, and only 15% offering multiple enrichment types. The study found no significant associations between the risk of tail biting and visible injuries, dirty flanks, or tucked tails, as assessed by the assessors (P > 0.05). Similarly, the risk of tail biting reported per pen was not associated with aggressive, damaging, or exploratory behaviours (P > 0.05). At the abattoir, 96% of pigs' tails exhibited minor skin damage, with only 4% showing moderate to severe damage. Furthermore, no links were found between the scores obtained during slaughter and the risk of tail biting, as reported by the assessors (P < 0.05). Although the tool was useful in identifying several improvements that could be made at farm level in areas such as stocking density, enrichment provision and reducing tail docking, overall the results underscored the need for improved training of assessors, and the challenge of associating management practices and animal based measures with tail-biting risk.

Cortisone in saliva of pigs: validation of a new assay and changes after thermal stress

BACKGROUND

Cortisone is derived from cortisol through the action of the enzyme 11β-hydroxysteroid dehydrogenase type II, and it has gained importance in recent years as a biomarker of stress. This study aimed to develop and validate an assay for the measurement of cortisone in pig saliva and evaluate whether its concentration varies in stressful situations. For this purpose, a specific immunoassay was developed and validated analytically, and a study was performed to evaluate whether cortisone concentrations in saliva can vary under heat stress conditions.

RESULTS

The assay proved to be accurate, reliable, and sensitive for the measurement of cortisone in pig saliva. The limit of detection of the assay was set at 0.006 ng/ml, and the lower limit of quantification was 0.023 ng/ml. It also correlated significantly with the results obtained by LC‒MS/MS (P = 0.003; r = 0.64). In addition, the cortisone concentration in animals subjected to prolonged heat stress decreased significantly 15 days after treatment (P < 0.0001).

CONCLUSIONS

According to these results, cortisone measured by this assay could be used as a tool for the non-invasive evaluation of thermal stress in pig saliva.

Combined Injection for Control of Iron-Deficiency Anemia and Coccidiosis in Piglets Decreases Stress at Management Time

The aim of the present study was to assess the short-term behavioral and physiological responses of piglets to different treatment protocols for the control of iron-deficiency anemia (IDA) and cystoisosporosis. Piglets were treated with either (1) an injection of iron combined with an oral application of toltrazuril (TLZ) by drenching or (2) a combination injection of TZL + gleptoferron; the behavior of the piglets was then evaluated. For this study, 288 piglets were divided into three experimental groups: 96 piglets were kept untreated (control group); 96 piglets received an oral administration of a generic TZL-based anticoccidial agent (20 mg/kg BW) along with intramuscular administration of iron dextran (200 mg/mL; 1 mL/piglet) at the same handling (oral + parenteral group, O + P); and 96 piglets received an intramuscular application of the combination product (parenteral group, P). For each treated piglet, the total handling time, flight reaction, and the intensity and frequency of vocalizations were determined using the methodology described by Scollo et al. (2020). Piglets in the O + P group were found to emit more screams during treatment administration than animals in the P group (21.05% vs. 8.42% of animals; p < 0.05). Piglets in the O + P group reacted worse to manipulation and oral administration because a higher percentage of animals continued to fidget even after handling (32.63% vs. 12.63%; p < 0.05). Differences in growth performance between the groups were not observed in our study (p > 0.05). In conclusion, the administration of a combination product reduced stress during administration, as indicated by reduced vocalizations and reactions to manipulation.

Swinepox virus: an unusual outbreak in free-range pig farms in Sicily (Italy)

BACKGROUND

Two outbreaks of swinepox were investigated in free-range domestic pig farms located in the northeastern side of Sicily, Italy. The disease is generally self-limiting with a low mortality rate, but morbidity can reach high rates in case of poor sanitary conditions, improper husbandry practices and ectoparasitic infestation. The presented cases are the first ever reported on the island and part of the few cases reported in domestic pigs.

CASE PRESENTATION

Carcasses condemned at the slaughterhouse and deceased pigs from Farm A and Farm B respectively, were referred for post-mortem examination and further investigations, with a strong suspect of SwinePox virus (SWPV) infection. Twelve deceased pigs were examined in total, showing poor body condition and pustular lesions scattered all over the cutaneous surfaces. Moreover, pigs from Farm B showed ocular lesions classified from Grade I to IV (from mild conjunctivitis to severe keratoconjunctivitis with corneal oedema, opacity, and ulcers). Final diagnosis was pursued by the microscopic assessment of skin lesions in both farms, which revealed the typical SWPV-lesion appearance, such as severe and disseminated ulcerative dermatitis and suspected inclusion bodies multifocally observed in the epidermis. Moreover, negative staining Electron Microscopy (nsEM) was performed on skin lesions and ocular swabs from Farm B, revealing in two samples the presence of brick-shaped viral particles, 220 nm long and 160 nm wide, with irregularly arranged surface tubules, identified as SWPV. The gene encoding the 482-bp fragment of the virus late transcription factor-3 was detected by PCR and sequencing revealed 99.79% identity and 100% query-cover with a strain previously isolated in Germany. Field clinical assessment was then performed in Farm B, revealing high overcrowding, poor sanitary conditions and improper husbandry practices, which are relevant risk factors for SWPV transmission.

CONCLUSIONS

The present is the first case report of SWPV in free-range pigs raised in Sicily, an island of the Southern coast of Italy, and wants to raise awareness on a neglected disease, and cause of animal health and welfare issues.

Welfare Assessment in Pigs Using the Salivary Proteome

Identifying the potential presence of stress at the pig farm is fundamental since it affects pig welfare. As a result, a reliable and straightforward tool to monitor stress could record the welfare status of the animals. Although numerous methods to assess the welfare of pigs have been developed in the past, no gold standard has been established yet. Recently, the value of saliva as a tool to identify chronic stress in piglets was explored, as it can be collected fast and non-invasively. Since the protein composition, i.e., the proteome of porcine saliva, responds to stress, the affected proteins could be used as salivary stress biomarkers. The present review first defines stress and its relationship with welfare. Next, the porcine gland-specific salivary proteome is characterized. Finally, six potential salivary biomarkers for stress are proposed, i.e., odorant-binding protein, vomeromodulin-like protein, chitinase, lipocalin-1, long palate lung and nasal epithelium protein, and alpha-2-HS-glycoprotein.

Effect on the splenocyte function of weaned piglets induced by continuous lipopolysaccharide injections

Introduction

When piglets are exposed to pathogens for a long period, the immune system organs, among them the spleen, play a major role in combating the stress caused by those pathogens. In the present study, the effect on splenocyte function was investigated in a model of weaned piglets in which stress was induced by multiple low doses of lipopolysaccharide (LPS).

Material and Methods

Forty-eight 28-day-old piglets were divided into two groups: the LPS group and the control group. During the experimental period of thirteen days, the LPS group was intraperitoneally injected with LPS (100 μg/kg) once per day, and the control group was injected with the same volume of 0.9% sterile saline. On the 1st, 5th, 9th and 13th days, the piglets' spleens were collected for isolating splenocytes. The proliferation ability of splenocytes was evaluated by the cell-counting-kit 8 method. Flow cytometry was used to detect cell cycle stage and apoptosis, and the nitric oxide level of cell supernatant was also tested.

Results

In the experimental group, the proliferation ability of splenocytes was enhanced, the proportion of cells in the G0/G1 phase was smaller, and cells were promoted to the S and G2/M phases. Meanwhile, apoptosis was suppressed and nitric oxide release upregulated. The results were significantly different between the LPS group and the control group on the 5th and 9th days.

Conclusion

The difference between the results of one group and those of the other suggest that after the 5th LPS injection, multiple low doses of LPS activated splenocytes and restored the number of splenocytes, which maintained and possibly enhanced the regulation of the immune function of the spleen.

Pharmacokinetics of oral clonazepam in growing commercial pigs (Sus scrofa domestica)

Clonazepam causes sedation and psychomotor impairment in people. Due to similarities between people and swine in response to benzodiazepines, clonazepam may represent a viable option to produce mild-to-moderate tranquillization in pigs. The objective of this study was to determine the pharmacokinetic profile of a single oral dose (0.5 mg/kg) of clonazepam in eight healthy, growing commercial cross pigs. Serial plasma samples were collected at baseline and up to 96 h after administration. Plasma concentrations were quantified using reverse-phase high-performance liquid chromatography, and compartment models were fit to time-concentration data. A one-compartment first-order model best fits the data. Maximum plasma concentration was 99.5 ng/mL, and time to maximum concentration was 3.4 h. Elimination half-life was 7.3 h, mean residence time 7.4 h, and apparent volume of distribution 5.7 L/kg. Achieved plasma concentrations exceeded those associated with psychomotor impairment in people although pharmacodynamic effects have not been investigated in pigs. A simulated oral regimen consisting of 0.35 mg/kg administered every 8 h to pigs would achieve plasma concentrations above 32 ng/mL which are shown to produce psychomotor impairment in people. Further studies to test the clinical efficacy of these dosages in commercial and miniature pigs are warranted.

Non-invasive methods for analysing pig welfare biomarkers

At present, the assessment of pig welfare quality has gained significant importance, prompting the exploration of novel biomarkers for this purpose. Traditionally, these biomarkers have been monitored in the blood; however, blood sampling is considered an invasive procedure. Currently, non-invasive methods for collecting samples are emerging as viable alternatives for assessing these biomarkers. This article aims to present the current knowledge regarding the use of non-invasive methods for analysing pig welfare biomarkers, specifically focusing on the saliva, hair, faeces, and urine as matrices to determine these biomarkers. The saliva analysis encompasses various biomarkers, such as cortisol, alpha-amylase, chromogranin A, the total esterase, oxytocin, acute phase proteins, adenosine deaminase, immunoglobulins and parameters of redox homeostasis. Cortisol, a specific biomarker, can be determined in the hair, urine and faeces, while urine samples allow for the analysis of catecholamines as non-invasive markers of pig welfare.

Validation of the slaughterhouse porcine heart model for ex-situ heart perfusion studies

INTRODUCTION

To validate slaughterhouse hearts for ex-situ heart perfusion studies, we compared cold oxygenated machine perfusion in less expensive porcine slaughterhouse hearts (N = 7) to porcine hearts that are harvested following the golden standard in laboratory animals (N = 6).

METHODS

All hearts received modified St Thomas 2 crystalloid cardioplegia prior to 4 hours of cold oxygenated machine perfusion. Hearts were perfused with homemade modified Steen heart solution with a perfusion pressure of 20-25 mmHg to achieve a coronary flow between 100-200 mL/min. Reperfusion and testing was performed for 4 hours on a normothermic, oxygenated diluted whole blood loaded heart model. Survival was defined by a cardiac output above 3 L with a mean aortic pressure above 60 mmHg.

RESULTS

Both groups showed 100% functional survival, with laboratory hearts displaying superior cardiac function. Both groups showed similar decline in function over time.

CONCLUSION

We conclude that the slaughterhouse heart can be used as an alternative to laboratory hearts and provides a cost-effective method for future ex-situ heart perfusion studies.

Animal Welfare Assessment and Meat Quality through Assessment of Stress Biomarkers in Fattening Pigs with and without Visible Damage during Slaughter

The study aimed to investigate the physiological and meat quality differences between Non-Ambulatory, Non-Injured (NANI), and without apparent abnormalities (non-NANI) pigs in a commercial slaughterhouse setting, focusing on the impact of stress and health conditions on the overall well-being and meat quality of the animals. A total of 241 surgically castrated crossbred male pigs from Southern Brazil were analyzed, with 131 non-NANI pigs and 110 NANI pigs. Infrared orbital temperature, rectal temperature, hematological parameters, and meat quality measurements were collected. Statistical analysis included ANOVA tests and principal component analysis (PCA). NANI pigs exhibited significantly higher infrared orbital temperatures and rectal temperature (p < 0.01). Hematological analysis revealed higher levels of hemoglobin, hematocrit, and red blood cells in NANI pigs (p < 0.05). White blood cell count and lactate dehydrogenase were significantly elevated in NANI pigs (p < 0.01), indicating potential infections or inflammatory responses. Meat quality parameters showed that NANI pigs had lower pH values, higher luminosity, and increased drip loss (p < 0.01), reflecting poorer water retention and potential muscle glycogen depletion. The study highlights the physiological and meat quality differences between NANI and non-NANI pigs, emphasizing the impact of stress, health conditions, and handling procedures on the animals. Blood biomarkers proved valuable in assessing physiological stress, immune response, and potential health issues in pigs, correlating with meat quality abnormalities. Utilizing these biomarkers as predictive tools can enhance animal welfare practices and contribute to improving meat quality in the swine industry.

Cloprostenol sodium improves reproductive performance of multiparous sows during lactation

This study aimed to determine the effect of prostaglandin F2α (PGF2α) analog (D-cloprostenol sodium and DL-cloprostenol sodium) administration on the milk yield of multiparous sows (MS) and piglet growth performance. In total, 320 Landrace×Yorkshire parturient MS were randomly divided into three groups on day 115 of pregnancy: without treatment (N = 50), with 75 μg D-cloprostenol sodium (N = 137), and with 200 μg DL-cloprostenol sodium (N = 133). After delivery, the sows treated with D-cloprostenol sodium and DL-cloprostenol sodium were randomly allocated into three subgroups, respectively: (i) no additional treatment after farrowing; (ii) administration of cloprostenol sodium at 3 h and 5 days after farrowing; and (iii) administration of cloprostenol sodium at 3 h, 5 days, and 10 days after farrowing. Cloprostenol sodium effectively induced sows to synchronize parturition approximately 23 h after administration and increased the daytime delivery rates (p < 0.05). Compared with DL-cloprostenol sodium, D-cloprostenol sodium shortened the farrowing duration and birth interval of sows for inducing farrowing (p < 0.05). Moreover, we observed that a single administration of both D-cloprostenol sodium and DL-cloprostenol sodium a day before delivery significantly reduced the rates of stillborn piglets type II in MS (p < 0.05). Compared to no treatment and single treatment with cloprostenol sodium, quartic treatments with cloprostenol sodium significantly increased the daily feed intake of MS, litter weight after weaning, and average daily gain of piglets (p < 0.05). Cloprostenol sodium improved the 21-day milk yield, with D-cloprostenol sodium showing the best effect, which increased lactation ability by 30.30% (176.72 kg vs. 135.63 kg) (p < 0.05). DL-cloprostenol sodium followed closely, increasing lactation ability by approximately 25.00% (169.71 kg vs. 135.63 kg) (p < 0.05). During lactation, sows administered with D-cloprostenol sodium observed increased serum prolactin levels. Compared to untreated sows, the sows administered with D-cloprostenol sodium and multiple DL-cloprostenol sodium visibly shortened the weaning-to-estrus interval (WEI) and weaning-to-service interval (WSI) (p < 0.05). Furthermore, quartic injections of D-cloprostenol sodium resulted in an 18 percentage point increase in the pregnancy rate of breeding sows compared to controls (82.61% vs. 64.58%) (p > 0.05). In summary, cloprostenol sodium could enhance the reproductive performance of MS, particularly in terms of lactation performance. Additionally, the effect of quartic injections of D-cloprostenol sodium was the most pronounced.

Advances in Research on Pig Salivary Analytes: A Window to Reveal Pig Health and Physiological Status

Saliva is an important exocrine fluid that is easy to collect and is a complex mixture of proteins and other molecules from multiple sources from which considerable biological information can be mined. Pig saliva, as an easily available biological liquid rich in bioactive ingredients, is rich in nucleic acid analytes, such as eggs, enzymes, amino acids, sugars, etc. The expression levels of these components in different diseases have received extensive attention, and the analysis of specific proteins, metabolites, and biological compositions in pig saliva has become a new direction for disease diagnosis and treatment. The study of the changes in analytes in pig saliva can provide a new strategy for early diagnosis, prognosis assessment, and treatment of diseases. In this paper, the detection methods and research progress of porcine salivary analytes are reviewed, the application and research progress of porcine salivary analytes in diseases are discussed, and the future application prospect is presented.

Experiences with transvaginal Ovum Pick-Up (OPU) in sows

Transvaginal ultrasound-guided Ovum Pick-Up (OPU) is an established technique in other species. Due to several challenges, there are few publications addressing the procedure in sows. An efficient OPU technique may allow for the collection of numerous oocytes from valuable sows for porcine in vitro embryo production, gene editing and cloning programmes, or cryopreservation. We aimed to improve transvaginal OPU and equipment for this technique in sows. In experiment 1, we conducted 13 OPU sessions on three Landrace x Large White hybrid sows under general anaesthesia, while the second experiment explored OPU in non-sedated animals (N = 6) physically restrained in a commercial claw trimming chute. The experiments resulted in 6.6 ± 5.6 (mean ± SD) and 7.7 ± 8.9 recovered cumulus-oocyte complexes per session, respectively. Post-mortem examination of the pelvic and abdominal cavities of the three sows subjected to repeated OPU sessions did not reveal major acute or chronic pathological lesions. The only sow which was inseminated after the experiment delivered 16 liveborn piglets at term. Salivary cortisol levels increased during the procedure in non-sedated and physically restrained sows but returned to baseline 1 h later (n = 5), indicating a short-term stress response. The described OPU technique and equipment have the potential to retrieve considerable numbers of oocytes by repeated procedures on valuable mature sows. Follow-up studies are needed to optimize the efficiency of the aspiration of high-quality oocytes and to describe the developmental competence of these OPU-derived oocytes. It is also essential to further investigate sow welfare during and after the procedure before recommending porcine transvaginal OPU as a sustainable and welfare-friendly procedure.

A microencapsulated blend of botanicals supports weaning piglets during a lipopolysaccharide challenge by modulating liver inflammation and intestinal integrity

This study examined the action of a blend of botanicals (BOT) against lipopolysaccharide (LPS)-induced inflammation on cultured hepatocytes and weaning piglets. In vitro studies examined HepG2 cells treated with BOT and challenged with Escherichiacoli LPS for 8 d. BOT treatment reduced IL-6 concentration in cell culture media across time (P < 0.05) and decreased pro-inflammatory cytokine expression on days 1 and 8 of experiment (TNFα, IL-1β; P < 0.05). BOT also increased the expression of antioxidant enzymes (GPX-2, SOD, CAT) on day 8 (P < 0.05), which was supported by lowered reactive oxygen species concentration after LPS challenge (P < 0.1). The in vivo study was conducted with 72 weaning pigs, allotted into 24 pens and divided into 3 groups: a negative control (CTR-, basal diet), a challenged control (CTR+) that received an intraperitoneal injection of E. coli O55:B5 LPS on days 14 and 16, and a challenged treated group which received a diet containing 1.5 g/kg of microencapsulated BOT (BOT+) for the whole duration of the study. Growth performance was determined weekly and, on days 21 (1 animal per pen) and 28 (remaining animals), pigs were sacrificed to collect liver and jejunal tissues. After the challenge, BOT+ pigs had increased BW on days 21 (P < 0.05) and 28 (P < 0.1) compared to CTR+. Similar improvements in average daily gain and FCR on days 14 to 21 (P < 0.05) and 21 to 28 (P < 0.1) were also seen in BOT+ group. In the liver, compared to CTR+ pigs, BOT+ pigs had downregulated expression of TLR-4, IL-6, IFN-γ on day 21 (P < 0.05), and TLR-4, TNF-α, IL-8 on day 28 (P < 0.05). BOT+ also increased GPX-2 expression on days 21 and 28 (P < 0.05), while also upregulating SOD-1 and SOD-2 on day 21 (P < 0.05) and CAT on day 28 (P < 0.05) compared to CTR+. In the jejunum, BOT+ reduced inflammation by affecting cytokine expression (P < 0.05) and increasing the expression of tight-junction proteins, ZO-1 on day 21 and CLD-1 on day 28 (P < 0.05). Furthermore, BOT+ pigs had lower crypt depth on days 21 (P < 0.1) and 28 (P < 0.05), and increased villi-to-crypt ratio on days 21 and 28 (P < 0.05). By day 28, BOT+ intestinal measurements were restored to values similar to the CTR-. Finally, BOT+ also reduced mast cell activation on day 21 (P < 0.05) compared to CTR+. Considering all the findings, BOT controlled inflammatory activation and oxidative stress in liver cells, enhanced intestinal integrity, and as a result improved the growth performance of weaning piglets challenged with LPS.

Effect of Pig Synthetic Pheromones and Positive Handling of Pregnant Sows on the Productivity of Nursery Pigs

Weaning is one of the most important stress events in the life of pigs, increasing the risk for health problems and reduced performance. The release of pheromones in pig stables can be considered an environmental enrichment and alleviate the negative effects of weaning stress in nursery pigs. The present study investigated the effect of synthetic pheromones on the performance of nursery pigs. The effect of positive handling of sows in the farrowing house on the performance of the offspring in the nursery was also investigated. The study was performed in a commercial pig farm and included 24 batches of weaned piglets (216 piglets per batch). Half of the batches originated from sows exposed to positive handling. This implied that music was played from 6.00 a.m. to 6.00 p.m. from the moment the sows entered the farrowing house until weaning and that they were subjected to backscratching from the day they entered the farrowing unit the day of farrowing. During the nursery period, half of the batches were treated, and half served as controls. Piglets of treated groups were exposed to a synthetic analog of the maternal pig appeasing pheromone (PAP) (SecurePig®, Signs, Avignon, France). The product consisted of a gel block from which the pheromones were slowly released into the room. Different performance parameters were measured during the nursery period. Neither the sow treatment nor the treatment with pheromones significantly influenced the performance of the piglets during the nursery period (p > 0.05). The median values (95% confidence interval) of average daily gain, namely 318 (282-338) vs. 305 (272-322) g/day, feed conversion ratio, namely 1.64 (1.51-1.71) vs. 1.70 (1.57-1.75), and number of antimicrobial treatment days, namely 16.9 (9.6-25.0) vs. 17.3 (9.5-25.0) days, were numerically better in the nursery pigs exposed to the pheromones compared to the control groups. Mortality however was numerically higher in the treated groups, namely 4.4 (2.8-6.8) vs. 3.2 (0.9-4.2)%. Under the conditions of the present production system, pigs exposed to the pheromone treatment during the nursery did not show a significant performance increase.

Identification of intestinal and fecal microbial biomarkers using a porcine social stress model

Understanding the relationships between social stress and the gastrointestinal microbiota, and how they influence host health and performance is expected to have many scientific and commercial implementations in different species, including identification and improvement of challenges to animal welfare and health. In particular, the study of the stress impact on the gastrointestinal microbiota of pigs may be of interest as a model for human health. A porcine stress model based on repeated regrouping and reduced space allowance during the last 4 weeks of the finishing period was developed to identify stress-induced changes in the gut microbiome composition. The application of the porcine stress model resulted in a significant increase in salivary cortisol concentration over the course of the trial and decreased growth performance and appetite. The applied social stress resulted in 32 bacteria being either enriched (13) or depleted (19) in the intestine and feces. Fecal samples showed a greater number of microbial genera influenced by stress than caecum or colon samples. Our trial revealed that the opportunistic pathogens Treponema and Clostridium were enriched in colonic and fecal samples from stressed pigs. Additionally, genera such as Streptococcus, Parabacteroides, Desulfovibrio, Terrisporobacter, Marvinbryantia, and Romboutsia were found to be enriched in response to social stress. In contrast, the genera Prevotella, Faecalibacterium, Butyricicoccus, Dialister, Alloprevotella, Megasphaera, and Mitsuokella were depleted. These depleted bacteria are of great interest because they synthesize metabolites [e.g., short-chain fatty acids (SCFA), in particular, butyrate] showing beneficial health benefits due to inhibitory effects on pathogenic bacteria in different animal species. Of particular interest are Dialister and Faecalibacterium, as their depletion was identified in a human study to be associated with inferior quality of life and depression. We also revealed that some pigs were more susceptible to pathogens as indicated by large enrichments of opportunistic pathogens of Clostridium, Treponema, Streptococcus and Campylobacter. Generally, our results provide further evidence for the microbiota-gut-brain axis as indicated by an increase in cortisol concentration due to social stress regulated by the hypothalamic-pituitary-adrenal axis, and a change in microbiota composition, particularly of bacteria known to be associated with pathogenicity and mental health diseases.

Listen to Us: Perceptions of Animal Voice and Agency

In many contexts, the interests of nonhuman animals (hereafter "animals") are often overlooked or considered to be a lower priority than those of humans. While strong arguments exist for taking animal moral claims seriously, these largely go unheard due to dominant anthropocentric attitudes and beliefs. This study aimed to explore how animal interests might be best represented in the human world. We conducted interviews to investigate people's perceptions of what it means to speak for other animals and who can reliably represent animal interests. Using Grounded Theory analytical methods, we identified one major theme: "Animal voice", and its subthemes: "Animals do/do not have a voice", "Human language constructs realities and paradigms", and "Let animals speak". Our findings illustrate how human language constructs contribute to shaping the realities of animals by contextually defining them as voiceless. This has serious implications for animals, society, and the environment. Drawing parallels with the relevant literature, our results reflect calls for the social and political recognition of animal voice as fundamental to animal representation. We recommend future research to focus on developing ethical and compassionate approaches to understanding animal subjective experiences to empower and amplify animal voices.

Interactions between corticotropin releasing factor signaling and prophylactic antibiotics on measures of intestinal function in weaned and transported pigs

The study objective was to evaluate the interaction between corticotrophin releasing factor (CRF) receptor signaling and prophylactic antibiotic administration on intestinal physiology in newly weaned and transported pigs. Pigs (n = 56; 5.70 ± 1.05 kg) were weaned (20.49 ± 0.64 d), a blood sample was taken, and then pigs were given an intraperitoneal injection of saline (SAL; n = 28 pigs) or a CRF receptor antagonist (CRFA; n = 28 pigs; 30 μg/kg body weight; Astressin B), and then were transported in a livestock trailer for 12 h and 49 min. A second and third intraperitoneal injection was given at 4 h 42 min and 11 h 36 min into the transport process, respectively. Following transport, 4 SAL and 4 CRFA pigs were blood sampled and euthanized. The remaining 48 pigs were individually housed and given dietary antibiotics [AB; n = 12 SAL and 12 CRFA pigs; chlortetracycline (441 ppm) + tiamulin (38.6 ppm)] or no dietary antibiotics (NAB; n = 12 SAL and 12 CRFA pigs) for 14 d post-transport. Blood was collected at 12 h and on d 3, 7, and 14, and then pigs were euthanized on d 7 (n = 24) and d 14 (n = 24) post-weaning and transport. Circulating cortisol was reduced (p = 0.05) in CRFA pigs when compared to SAL pigs post-weaning and transport. On d 7, jejunal villus height and crypt depth was greater overall (p < 0.05) in AB-fed pigs versus NAB-fed pigs. On d 14, ileal crypt depth was reduced (p = 0.02) in CRFA pigs when compared to SAL pigs. Jejunal CRF mRNA abundance tended to be reduced (p = 0.09) on d 7 in CRFA pigs versus SAL pigs. On d 14, jejunal tumor necrosis factor-alpha was reduced (p = 0.01) in AB-fed pigs versus NAB-fed pigs. On d 7, change in glucose short-circuit current tended to be increased (p = 0.07) in CRFA pigs fed the AB diet when compared to CRFA pigs fed the NAB diet. In conclusion, CRFA pigs and pigs fed AB had some similar biological intestinal function measures post-weaning and transport.

Bioavailability of Li-enriched mushrooms and protection against oxidative stress in pigs: First study in vivo

Mycelia and mushrooms are able to bioaccumulate minerals. Lithium is the active principle of drugs used in the treatment of psychiatric diseases. However, a dietary source of Li can reduce the side effects of these drugs. Thus, the objective of this study was to evaluate the bioavailability of Li-enriched mushroom of Pleurotus djamor in pigs and the effects of this element on oxidative stress in the animal tissues. Pigs 28-30 days-old were fed with diets containing or not Li for five days. Levels of serum cortisol were related to the Li dosage from diet. Li-enriched mushrooms were more bioavailable source of Li to the body than Li2CO3. These mushrooms also improved the effects of oxidative enzymes and showed less oxidative damage than Li2CO3. These results demonstrate the potential to use Li-enriched P. djamor as a source of Li that is more bioavailable and present protective effects against oxidative stress.

Influence of age and seasonality on boar seminal plasma steroids quantification: A preliminary study

Background and Aim

Seasonal changes, especially temperature and photoperiod, are well-known determining factors of swine reproductive capacity, but the underlying mechanisms remain unknown. This study aimed to investigate the effect of age and seasonal variations on boar seminal plasma steroids (dehydroepiandrosterone [DHEA], cortisol [CORT], and testosterone [TEST]) over 1 year.

Materials and Methods

Four commercial hybrid adult boars (Large White × Duroc), aged between 12 and 44 months, were repeatedly evaluated at the Department of Veterinary Medical Sciences of the University of Bologna. Daily temperature and light hours relating to the collection date were considered for each observation within the four astronomical seasons: Winter, spring, summer, and autumn. Hormones were quantified using radioimmunoassay. The association between seasonal factors and hormone concentrations was evaluated using linear regression models. Univariate models were estimated for each hormone to assess the influence of the independent variables; two multivariate models were assessed to evaluate the effect of temperature and daylight hours, including boar and season factors.

Results

Age significantly affected all analyzed hormones (CORT p < 0.0001; DHEA p < 0.0001; and TEST p < 0.0001). The highest average levels were found for each hormone during summertime, suggesting a positive correlation between steroid concentrations with temperature and light hours.

Conclusion

The results of this study support the hypothesis that the increase in external temperature and light hours is somehow associated with higher levels of steroid concentrations in the seminal plasma of in-housed boars. These findings may help further investigate seasonal fluctuations in reproductive outcomes, which are well-known for porcine species.

A blend of selected botanicals maintains intestinal epithelial integrity and reduces susceptibility to Escherichia coli F4 infection by modulating acute and chronic inflammation in vitro

In the pig production cycle, the most delicate phase is weaning, a sudden and early change that requires a quick adaptation, at the cost of developing inflammation and oxidation, especially at the intestinal level. In this period, pathogens like enterotoxigenic Escherichia coli (ETEC) contribute to the establishment of diarrhea, with long-lasting detrimental effects. Botanicals and their single bioactive components represent sustainable well-recognized tools in animal nutrition thanks to their wide-ranging beneficial functions. The aim of this study was to investigate the in vitro mechanism of action of a blend of botanicals (BOT), composed of thymol, grapeseed extract, and capsicum oleoresin, in supporting intestinal cell health during inflammatory challenges and ETEC infections. To reach this, we performed inflammatory and ETEC challenges on Caco-2 cells treated with BOT, measuring epithelial integrity, cellular oxidative stress, bacterial translocation and adhesion, gene expression levels, and examining tight junction distribution. BOT protected enterocytes against acute inflammation: while the challenge reduced epithelial tightness by 40%, BOT significantly limited its drop to 30%, also allowing faster recovery rates. In the case of chronic inflammation, BOT systematically improved by an average of 25% the integrity of challenged cells (p < 0.05). Moreover, when cells were infected with ETEC, BOT maintained epithelial integrity at the same level as an effective antibiotic and significantly reduced bacterial translocation by 1 log average. The mode of action of BOT was strictly related to the modulation of the inflammatory response, protecting tight junctions' expression and structure. In addition, BOT influenced ETEC adhesion to intestinal cells (-4%, p < 0.05), also thanks to the reduction of enterocytes' susceptibility to pathogens. Finally, BOT effectively scavenged reactive oxygen species generated by inflammatory and H2O2 challenges, thus alleviating oxidative stress by 40% compared to challenge (p < 0.05). These results support the employment of BOT in piglets at weaning to help manage bacterial infections and relieve transient or prolonged stressful states thanks to the modulation of host-pathogen interaction and the fine-tuning activity on the inflammatory tone.

Risk factors associated with Streptococcus suis cases on pig farms in Spain

BACKGROUND

Streptococcus suis can cause meningitis, polyarthritis and acute death in piglets. However, the risk factors associated with S. suis infection remain incompletely understood. Therefore, a longitudinal study was carried out, in which six batches from two Spanish pig farms with S. suis problems were repeatedly examined to determine possible risk factors.

METHODS

A prospective case-control study was conducted, and potential risk factors were evaluated using mixed-effects logistic regression models. The explanatory variables included: (a) concomitant pathogens; (b) biomarkers associated with stress, inflammation and oxidative status; (c) farm environmental factors; and (d) parity and S. suis presence in sows. Three models were built to study the effect of these variables, including two to assess the risk factors involved in the subsequent development of disease.

RESULTS

Risk factors for S. suis-associated disease included porcine reproductive and respiratory syndrome virus co-infection at weaning (odds ratio [OR] = 6.69), sow parity (OR = 0.71), haptoglobin level before weaning (OR = 1.01), relative humidity (OR = 1.11) and temperature (OR = 0.13).

LIMITATIONS

Laboratory diagnosis was done at the batch level, with individual diagnosis based on clinical signs only.

CONCLUSIONS

This study confirms the multifactorial nature of S. suis-associated disease, with both environmental factors and factors related to the host involved in disease development. Controlling these factors may, therefore, help prevent the appearance of disease.

Acupuncture Treatment Improves Transport Stress in Microminipigs Through the Acupoint in Ears

BACKGROUND/AIM

This study aimed to investigate the effects of acupuncture treatment through the ear acupoints on transport stress in experimental microminipigs.

MATERIALS AND METHODS

Experiment 1: Six animals were equally divided into two groups (Control and Treatment). In the treatment group, before transportation (6 h; vehicle and plane), short, ultrathin circular transdermal needles were applied to locations corresponding to the acupoints on the apical area of both ears. Peripheral blood samples were collected from the cranial vena cava 2 days before and immediately after transportation. Blood stress markers, biochemistry indicators, and oxidative stress levels were examined. Experiment 2 (follow-up study: diarrhea incidence after transportation): Diarrhea incidence after transportation in the control and treatment groups was investigated.

RESULTS

Experiment 1: Transport stress induced an increase in blood cortisol, serum amyloid A (SAA), glucose, non-esterified fatty acid, and derivatives of reactive oxygen metabolites (d-ROMs) and decreased the biological antioxidant potential (BAP)/d-ROMs ratio yet did not affect BAP. Acupuncture suppressed the increases in SAA and d-ROMs values and the decrease in BAP/d-ROMs ratio. Experiment 2: The total diarrhea incidence was 25% in the control group, whereas diarrhea was not observed in the treatment group.

CONCLUSION

Acupuncture treatment suppresses hypothalamic-pituitary-adrenal function and, as a result, reduces transport stress without affecting the suppression of the central catecholaminergic system. Acupuncture treatment for transport stress can improve animal welfare.

Indicators of improved gestation housing of sows. Part I: Effects on behaviour, skin lesions, locomotion, and tear staining

Commercial gestation housing systems for sows generally fail to cater fully for their needs in terms of comfort or the ability to perform highly motivated behaviours, which can lead to chronic stress and an impairment to welfare. We compared a typical gestation system (CONTROL) with an IMPROVED one as regards oral stereotypies, aggressive behaviour, skin lesions, locomotion, and tear staining. Sows were mixed into 12 stable groups (six groups per treatment, 20 sows per group), 29 days post-service in pens with free-access, full-length individual feeding/lying stalls. CONTROL pens had fully slatted concrete floors, with two blocks of wood and two chains suspended in the group area. IMPROVED pens were the same but with rubber mats and a length of manila rope in each feeding stall, and straw provided in three racks in the group area. Direct observations of oral stereotypical (30 instantaneous scans per sow per day) and aggressive (all-occurrence sampling, 3 h per sow per day) behaviours were conducted 72 h post-mixing, in mid and late gestation. Skin lesions were counted 24 h and three weeks post-mixing, and in late gestation. Sows' locomotion (locomotory ability) was scored using a visual analogue scale in mid and late gestation. Right and left eye tear staining was scored in late gestation. Indications of better welfare in IMPROVED sows included performance of fewer oral stereotypies in mid and late gestation, and lower tear stain scores. These sows performed more aggression in late gestation, which was associated with access to enrichment, but skin lesion counts were not affected. Thus, the changes made in the IMPROVED treatment benefitted aspects of sow welfare.

Indicators of improved gestation housing of sows. Part II: Effects on physiological measures, reproductive performance and health of the offspring

Prenatal stress is the mechanism through which poor welfare of pregnant sows has detrimental effects on the health and resilience of their piglets. We compared two gestation housing systems (IMPROVED versus [conventional] CONTROL) in terms of sow stress and welfare indicators and sought to determine whether potential benefits to the sows would translate into improved offspring health. Sows were mixed into 12 stable groups (six groups per treatment, 20 sows per group) 29 days post-service in pens with free-access, full-length individual feeding/lying-stalls. CONTROL pens had fully slatted concrete floors, with two blocks of wood and two chains suspended in the group area. IMPROVED pens were the same but with rubber mats and manila rope in each stall, and straw provided in three racks in the group area. Saliva was collected from each sow on day 80 of pregnancy and analysed for haptoglobin. Hair cortisol was measured in late gestation. Sows' right and left eyes were scored for tear staining in mid lactation and at weaning. Numbers of piglets born alive, dead, mummified, and total born were recorded. Piglets were weighed and scored for vitality and intra-uterine growth restriction (IUGR) at birth. Presence of diarrhoea in farrowing pens was scored every second day throughout the suckling period. IMPROVED sows had lower haptoglobin levels and tear-stain scores during lactation. IMPROVED sows produced fewer mummified piglets, and these had significantly lower IUGR scores, and scored lower for diarrhoea than piglets of CONTROL sows. Hence, improving sow welfare during gestation improved the health and performance of their offspring.

Changes in cortisol and cortisone in hair of pigs reared under heat stress conditions

Heat stress accounts for millions of dollars in losses for swine producers worldwide. The aim of the present study was to determine and evaluate cortisol and cortisone in hair as indicators of thermal stress in growing pigs reared under high environmental temperatures. The study was carried out in two independent batches of commercial crosses of Lean Duroc and Pietrain in trials 1 and 2, respectively, during the growing period (from 40 to 100 kg; 81 days in trial 1 and 77 days in trial 2) in the same commercial farm in Spain during the summers of 2020 and 2021. In both cases, four rooms were used. In Trial 1, Room 1 had cooling and 11 pigs per pen; Room 2 had no cooling and 13 pigs per pen; Room 3 had no cooling and 11 pigs per pen, and Room 4 had cooling and 13 pigs per pen. In Trial 2, Rooms 2 and 3 had cooling and rooms 1 and 4 had no cooling, and all of them had 13 pigs per pen. Mean THI value was higher (p < 0.0001) in rooms without cooling systems (75.0 trial 1; 74.9 trial 2) than with them (71.3 trial 1; 71.7 trial 2). A total of four pens per room (16 in total) was selected for analysis of hair corticoids and all pigs inside were sampled at the end of the study. Fifty percent of the pigs were males (castrated and intact in trial 1 and 2, respectively) and 50% females. In total, 44, 52, 44, and 52 pigs, respectively, were sampled in four rooms from the first trial and 52 for each of four rooms in Trial 2. Cortisol concentrations in hair did not show any significant change in relation to cooling-non-cooling in any trial. However, hair cortisone concentration was 172.3 pg./mg and 105.8 pg./mg less (p < 0.001) in pigs housed with cooling systems compared to those without them in Trial 1 and 2, respectively. In addition, the cortisone/cortisol ratio, which is an estimator of the activity of 11β-hydroxysteroid dehydrogenase (11β-HSD) type 2, was also greater in rooms without cooling than in rooms with cooling in both trials (p < 0.0001 and p = 0.0105 for Trials 1 and 2, respectively). In relation to the sex effect, the results showed greater levels in females than in castrated males both in cortisone and the cortisol/cortisone ratio while cortisol hair levels were greater in intact males than in females. Therefore, the use of cortisone and the estimation of 11β-HSD type 2 activity in hair is recommended to evaluate the chronic stress produced by high environmental conditions in pigs instead of using hair cortisol concentrations alone.

Performance of commercial growing-finishing pigs fed supplemental isoquinoline alkaloids: a statistical process control analysis

BACKGROUND

Statistical Process Control (SPC) is a powerful statistical tool that can be used in animal production to evaluate the evolution of production parameters overtime in response to the implementation of a specific strategy. The aim of this study was to evaluate the effect of supplementing growing-finishing pigs with isoquinoline alkaloids (IQ) on growth performance parameters by using the SPC method. IQ are natural secondary plant metabolites which have been extensively investigated in food animals due to their efficacy in supporting growth performance and the overall health status. Performance parameters and medication usage were collected from 1,283,880 growing-finishing pigs fed the same basal diet, 147,727 of which were supplemented with IQ from day 70 of life until slaughter.

RESULTS

Supplementation with IQ improved feed conversion ratio, while feed intake and daily gain were maintained.

CONCLUSION

SPC methods are useful statistical tools to evaluate the effect of using a new feed additive in the feed of pigs on growth performance at a commercial level. Additionally, IQ supplementation improved growth performance and it can be considered as a good strategy to reduce feed conversion in growing-finishing pigs.

Dietary Ulva lactuca and CAZyme supplementation improve serum biochemical profile and hepatic composition of weaned piglets

Ulva lactuca is a seaweed with antinutritional cell wall for monogastrics. Carbohydrate-Active enZymes (CAZymes) supplementation can potentially cause its disruption. This study evaluates four diets: Ctrl-control diet; UL-control + 7% U. lactuca (wild caught, powdered form); ULR-UL + 0.005% Rovabio^® Excel AP; ULU-UL + 0.01% ulvan lyase on piglets' haematologic and serologic profiles, hepatic lipids and minerals. White blood cells and lymphocytes reached the highest values in piglets fed UL compared to control, and to control and ULR; respectively (P < 0.05). IgG levels were boosted by seaweed incorporation compared to control (P = 0.015). The glycaemic homeostasis was assured by the seaweed inclusion. Dietary seaweed decreased serum lipids (P < 0.001), with the exception of ULU, due to HDL-cholesterol increase (P < 0.001). Cortisol was decreased in ULR and ULU (P < 0.001). No systemic inflammation was observed (P > 0.05). While hepatic n-3 PUFA increased in piglets fed with seaweed diets due to increment of beneficial 22:5n-3 and 22:6n-3 fatty acids (P < 0.05), the opposite occurred for n-6 PUFA, PUFA/SFA and n-6/n-3 ratios (P < 0.05). Hepatic pigments were unchanged (P > 0.05). ULR reduced α-tocopherol levels (P = 0.036) and increased serum potassium levels (P < 0.001) compared to control. Seaweed contributed to overcome piglets' weaning stress, with some benefits of including CAZyme supplementation.

Into the backyard: Multiple detections of PCV-2e in rural pig farms of Northern Italy. An unexpected ecological niche?

Porcine circovirus type 2 (PCV-2) is among the most burdensome viruses of the swine industry globally. Several genotypes have been periodically emerging, but just three of them (PCV-2a, PCV-2b, and PCV-2d) seem to circulate worldwide and be associated with the disease. Conversely, the spatial-temporal distribution of minor genotypes appears limited and their clinical relevance is still unclear. Recently PCV-2e was incidentally detected for the first time in Europe in a breeding farm in Northeastern Italy, while no connection could be established with countries where this genotype had been previously detected. To investigate circulating genotypes in the neglected rural context and provide a comparison with the most explored industrial context, a molecular survey was performed on samples collected in rural (n = 72) and industrial farms (n = 110) located in the same geographic area. Phylogenetic analysis surprisingly evidenced PCV-2e circulation only in pigs reared in backyard farms (n = 5), while major genotypes (PCV-2a, -2b, -2d) circulate in both rearing contexts. However, the close genetic similarity between the herein detected PCV-2e strains and the previously reported one testify that, although unusual, such rural-to-industrial strains exchange affected also PCV-2e. The greater genetic and phenotypic diversity of PCV-2e genotype compared to other ones might threaten the protection granted by current vaccines. The present study suggests the rural context as an ecological niche for the circulation of PCV-2e, and even of other minor genotypes. PCV-2e detection in pigs with outdoor access further stresses the epidemiological role of backyard farms as interfaces for pathogen introduction, potentially ascribable to the different rearing approaches, lower managerial and biosecurity capabilities, and easier contacts with wildlife.

Characteristics of the nasal mucosa of commercial pigs during normal development

The nasal mucosa is constantly exposed to inhaled pathogens and is the first defence against respiratory infections. Here, we investigated the structural and compositional characteristics of the nasal mucosa of commercial pigs at various growth stages. The epithelial thickness, number of capillaries, and secretion function of the nasal mucosa dramatically increased with age; however, underlying lymphoid follicles in the respiratory region were rarely observed across the growth stages. The nasal mucosa was explored at the epithelial, immunological, and biological (commensal microbiota) barriers. In the epithelial barrier, the proliferative capacity of the nasal epithelia and the expression of tight junction proteins were high after birth; however, they decreased significantly during the suckling stage and increased again during the weaning stage. In the immunological barrier, most pattern recognition receptors were expressed at very low levels in neonatal piglets, and the innate immune cell distribution was lower. During the suckling stage, increased expression of Toll-like receptor (TLR) 2 and TLR4 was observed; however, TLR3 expression decreased. TLR expression and innate immune cell quantity significantly increased from the weaning to the finishing stage. In the biological barrier, Firmicutes, Actinobacteria, Proteobacteria, and Bacteroidetes comprised the dominant phyla in neonatal piglets. A dramatic decrease in nasal microbial diversity was observed during the suckling stage, accompanied by an increase in potentially pathogenic bacteria. Proteobacteria, Bacteroidetes, and Firmicutes were identified as the core phyla of the nasal microbiota; among these, the three dominant genera, Actinobacter, Moraxella, and Bergerella, may be opportunistic pathogens in the respiratory tract. These characteristics comprise an essential reference for respiratory infection prevention at large-scale pig farms.

Effect of Laminaria digitata dietary inclusion and CAZyme supplementation on blood cells, serum metabolites and hepatic lipids and minerals of weaned piglets

Seaweeds, such as Laminaria digitata, are a sustainable alternative to conventional feedstuffs for weaned piglet diets, improving their health and mitigating environmental impacts. L. digitata has a complex cell wall that can be difficult for monogastrics to digest. However, carbohydrate-active enzymes (CAZymes) such as Rovabio® Excel AP and alginate lyase can help break down these polysaccharides and render intracellular nutrients more accessible. This study aimed to evaluate the impact of 10% L. digitata feed inclusion and CAZyme supplementation on piglet blood cells, serum metabolites, liver lipid and mineral profiles. Forty weaned piglets were randomly assigned to one of four diets (n = 10 each): a control diet, 10% L. digitata (LA), 10% L. digitata + 0.005% Rovabio® Excel AP (LAR), and 10% L. digitata + 0.01% alginate lyase (LAL). After two weeks of trial, animals were slaughtered and liver and blood serum samples taken for analysis. The results showed that the LA and LAL diets increased blood lymphocytes, IgG and IgM, and decreased serum lipids, improving both cellular and humoral immune response and cardiovascular health. Dietary CAZymes reversed the anti-inflammatory and hematopoietic effects. Additionally, cortisol levels were reduced with seaweed inclusion compared to the control diet (P < 0.001). In the liver, total n-3 PUFA and n-6/n-3 ratio were increased and decreased, respectively, due to eicosapentaenoic acid and α-linolenic acid accumulation (P < 0.001). However, total liver mineral content was incorporated to a lesser extent with the combined seaweed and enzyme diets (P < 0.001), potentially indicating a negative effect on mineral bioavailability. Overall, results suggest that a 10% L. digitata inclusion can effectively improve piglet health by reducing stress during weaning, without the need for dietary CAZymes.

Mixed management in growing and finishing pigs: Differences between gender and their impacts on behavior, growth performance, and physiological parameters

Mixing, a common management strategy used to regroup pigs, has been reported to impair individual performance and affect pig welfare because of the establishment of a new social hierarchy after regrouping. In this study we aimed to determine whether mixing management (non-mixed vs. mixed) and gender (gilts vs. barrows) affect the social and non-social behavior, performance, and physiological parameters of pigs. A total of 96 growing pigs (48 barrows and 48 females) were separated into two treatments: control (CT)-pigs that were mixed once during the growing-finishing period; and social stress (SS)-pigs that were mixed thrice during the growing-finishing period. We recorded social and non-social behaviors, injury score, performance, and physiological parameters during the experimental period. Data were grouped by the period, based on each mix performed, and overall values. The statistical analysis performed considered gender and treatment. For treatment, during period-II and III, the SS group presented the highest frequency of agonistic interactions (AI), stayed longer lying laterally (LL) and sternly (LS), and explored more enrichment material (ER) than the CT group. Furthermore, SS pigs presented the highest injury score in the ear, head, and middle and posterior regions. Compared to the females, the barrows spent more time at the electronic feed station and initiated most of the agonistic interactions during period-II, and they presented a higher injury score for the ear and head regions during period-III. In conclusion, repeated regrouping significantly affected social and feeding behavior without severely altering performance and physiological parameters. Furthermore, different patterns of social and feeding behavior, agonistic interactions, and injury scores between barrows and females were observed. This study provides an understanding of the impact of mixing management and gender differences on pigs, and this knowledge can be used to improve swine productivity and welfare.

Efficacy of the intranasal application of azaperone for sedation in weaned piglets

The aim of the study was to compare the efficacy of the intranasal and parenteral administration of azaperone in order to achieve pig sedation. A total of 32 weaned piglets divided into 4 groups (8 piglets in each group) were used. Group A was injected intramuscularly (i.m.) with azaperone (Stresnil®, 40 mg/ml inj.; Elanco Animal Health) at a dose of 2 mg/kg of body weight (b.w.). Group B received a dose of 2 mg/kg b.w. of azaperone intranasally. Group C was given azaperone intranasally at a dose of 4 mg/kg b.w. Group D was given 1 ml of saline intranasally and served as the control group. The response to the defined stimulus (a blunt blow of a metal rod into a metal edge of a pen), the degree of salivation, movement level, body temperature and serum azaperone concentration were included in the trial. We found that in order to induce an adequate level of sedation comparable to the standard method of application, i.e., 2 mg/kg b.w. i.m., the intranasal administration of azaperone at a dose of 4 mg/kg body weight is required.

Citrus Flavonoids Supplementation as an Alternative to Replace Zinc Oxide in Weanling Pigs’ Diets Minimizing the Use of Antibiotics

Since citrus flavonoids have antioxidant and anti-inflammatory properties, it was hypothesized that these compounds would become a suitable alternative to the use of therapeutic doses of zinc oxide at weaning. A total of 252 weaned pigs ([LargeWhite × Landrace] × Pietrain) were distributed according to BW (5.7 kg ± 0.76) into 18 pens (6 pens per diet, 14 pigs/pen). Three experimental diets for the prestarter (0–14 d postweaning) and starter (15–35 d postweaning) period were prepared: (i) a nonmedicated (CON) diet, (ii) a CON diet supplemented with zinc oxide at 2500 mg/kg, amoxicillin at 0.3 mg/kg and apramycin at 0.1 mg/kg (ZnO), and (iii) CON diet with the addition of a commercial citrus flavonoid extract at 0.3 mg/kg and amoxicillin at 0.3 mg/kg (FLAV). Pig BW, ADG, ADFI, and FCR were assessed on d7, d14, and d35, and ADFI and FCR were calculated. Samples of intestinal tissue, cecal content, and serum were collected on day seven (18 piglets). FLAV treatment achieved greater BW and ADG during the starter and for the entire experimental period compared with the CON diet (p < 0.05), whereas ZnO pigs evidenced intermediate results. Jejunum tissue analysis showed that pigs fed the FLAV diet overexpressed genes related to barrier function, digestive enzymes, and nutrient transport compared to those pigs fed the CON diet (p < 0.05). An increase in the abundance of bacterial genera such as Succinivibrio, Turicibacter, and Mitsuokella (p < 0.05) was observed in the FLAV compared with the CON and ZnO piglets. ZnO and FLAV increased the expression of TAS2R39, while ZnO pigs also expressed greater TAS2R16 than CON (p < 0.05) in the intestine. FLAV treatment improved the gut function, possibly explaining a higher performance at the end of the nursery period. Consequently, citrus flavonoids supplementation, together with amoxicillin, is a promising alternative to the use of zinc oxide plus amoxicillin and apramycin in weanling pigs, minimizing the use of antibiotics.

Animal Welfare Assessment Protocols for Bulls in Artificial Insemination Centers: Requirements, Principles, and Criteria

Animal welfare is a complex subject; as such, it requires a multidimensional approach with the main aim of providing the animals with the "five freedoms". The violations of any one of these freedoms could have an influence on animal wellbeing on different levels. Over the years, many welfare quality protocols were developed in the EU thanks to the Welfare Quality^® project. Unfortunately, there is a lack of such summarized information about bull welfare assessment in artificial insemination stations or about how disturbed welfare can be reflected in their productivity. Animal reproduction is the basis for the production of meat and milk; therefore, factors contributing to reduced fertility in bulls are not only indicators of animal welfare but also have implications for human health and the environment. Optimizing the reproductive efficiency of bulls at an early age can help to reduce greenhouse gas emissions. In this review, welfare quality assessment will be evaluated for these production animals using reproduction efficiency as a key area, focusing on stress as a main effect of poor animal welfare and, thereby, reduced fertility. We will address various welfare aspects and possible changes in resources or management to improve outcomes.

A casework study: The effect of the porcine digestive process on animal carcasses and human teeth

What happens if a human body is fed to pigs? Although a popular notion in the entertainment industry, no scientific published literature exists that documents this porcine feeding behaviour, nor, more importantly, what elements of the cadaver may survive such a process. A study conducted in 2020, born out of a casework enquiry, aimed to investigate the following two questions; Would pigs feed on a human body? And, if so, what could be recovered post feeding event? Kangaroo carcasses, porcine carcasses (as human analogues) and 90 human teeth were prepared, and fed, to two domestic pigs, in a variety of feed scenarios. Biological traces including bones, bone fragments, teeth and tooth fragments were recovered both post-digestion from the faeces of the pigs, as well as uneaten from the porcine enclosure. 29% of all human teeth were recovered from the study; 35% of which were recovered post-digestion from the faeces and 65% were recovered uneaten from the porcine enclosure, Of the recovered human teeth, 81% were deemed suitable for identification by a forensic odontologist. From the 447 bones recovered from the enclosure, 94% could be identified to a bone type and species. From all 3338 bone fragments recovered from the faeces of the pigs, none retained any morphological traits that would allow further intelligence to be generated. Overall, it was found that pigs will feed on human analogues and will consume soft tissue, bones, and human teeth. Biological traces in the form of bones, bone fragments, teeth and tooth fragments may be recovered both post-digestion from the faeces, or from the porcine enclosure. The biological traces can be used for identification of an individual via forensic odontology, identification of a species via forensic anthropology and may be suitable for DNA analysis. The outcomes of this study generated new avenues for investigation in the case and may be used to inform future operational resources.

Acute phase proteins in cattle and swine: A review

The major acute phase proteins (APPs) in cattle are haptoglobin (Hp) and serum amyloid A (SAA), and in swine, are Hp, SAA, C-reactive protein (CRP), and Pig major acute phase protein (Pig-MAP). Many methodologic assays are presently available to measure these parameters, which are still being improved to increase their specificity, sensitivity, user-friendliness, and economic availability. In cattle, the main applications are the diagnosis and monitoring of frequent diseases such as mastitis and metritis in dairy cows and respiratory problems in young calves. In pigs, APPs are useful in the control of bacterial and viral infections, and they may be used at the slaughterhouse to monitor subclinical pathologies and improve food safety. The utility of APP in animal production must not be forgotten; optimization of protocols to improve performance, welfare, and nutrition may benefit from the use of APPs. Other sample types besides serum or plasma have potential uses; APP determination in milk is a powerful tool in the control of mastitis, saliva is a non-invasive sample type, and meat juice is easily obtained at the slaughterhouse. Increasing our knowledge of reference intervals and the influence of variables such as age, breed, sex, and the season is important. Finally, worldwide harmonization and standardization of analytical procedures will help to expand the use of APPs.

Piglets' behaviour and performance in relation to sow characteristics

The importance of maternal care in commercial pig production is largely ignored. The sow has little possibility to interact with her piglets, and piglets are often subjected to early weaning or artificial rearing. This study aimed to investigate aspects of physiological and behavioural maternal provisioning that contribute to offspring outcomes. We hypothesised that better maternal care and nutritional provisioning would relate positively to piglet immunity, growth and behaviour. Nineteen sows and their litters were studied in free-farrowing pens. Oxytocin and tumour necrosis factor-α in colostrum/milk and salivary cortisol were sampled from sows throughout lactation. Sows were assessed for dominance rank, response to handling, maternal defensiveness, suckling initiation and termination, posture and sow-piglet contact. Piglets were weighed, measured for body mass index (BMI) and sampled for blood (Immunoglobulin G; at birth). After weaning, they experienced a human approach test (HAT) and novel object test. Correlations were explored between individual sow characteristics, individual piglet outcomes, and between sow characteristics and piglet outcomes averaged by litter. Significant correlations between sow and piglet factors were analysed at the litter level in mixed models with piglet outcomes as response variables and sow characteristics as predictor variables, while accounting for sow parity, litter size and batch. Litters grew faster when their sow had lower cortisol values (P = 0.03), while sows with lower cortisol levels had more successful suckling bouts and engaged in greater amounts of sow-piglet contact. Litters had a lower BMI at weaning when the sow had a higher milk fat percentage at d3. Litters of the most dominant sows took longer to approach the human in the HAT, while litters of sows with higher cortisol at d0 took longer to approach the novel object when assessed on correlations (r = 0.82, P < 0.001) but not when the model accounted for parity and litter size (P = 0.35). Only some of the measured nutritive and non-nutritive sow factors influenced litter performance and behaviour, with parity and litter size also playing a role. Given the continued increase in litter size, but also the interest in loose-housed lactation pens for sows, further research on sows' maternal investment and how it can be optimised is warranted.

Hierarchy Establishment in Growing Finishing Pigs: Impacts on Behavior, Growth Performance, and Physiological Parameters

In recent years, an increased number of studies have dealt with the analysis of social dominance related to animal behavior, physiology, and performance. This study aimed to investigate whether hierarchical ranking affects the coping style, non-social behavior during open field and novel object tests, performance, and physiological parameters of pigs. A total of 48 growing pigs (24 barrows and 24 females) were mixed three times during the growing-finishing period. The social and non-social behaviors of pigs were directly noted, and three behavioral tests were performed during the experimental period. Performance and physiological parameters were also recorded. Statistical analysis considered hierarchical classification (dominant vs. intermediary vs. subordinate) and p-values ≤ 0.05 were considered significant. After three regroupings, the pigs in different hierarchical classifications showed no change in hair cortisol values and open-field and novel object tests. Mean corpuscular hemoglobin concentration and leukocyte values increased in intermediary pigs, and the lowest counts were found in pigs classified as dominants. Furthermore, dominant pigs visited the feeder more but spent shorter time there compared to subordinate and intermediary pigs. Our results suggest that hierarchical classification influenced feeding behavior and physiological parameters without affecting cortisol values and growth performance, demonstrating a possible compensation skill.

Different Types of Glucocorticoids to Evaluate Stress and Welfare in Animals and Humans: General Concepts and Examples of Combined Use

The main glucocorticoids involved in the stress response are cortisol and cortisone in most mammals and corticosterone in birds and rodents. Therefore, these analytes are currently the biomarkers more frequently used to evaluate the physiological response to a stressful situation. In addition, "total glucocorticoids", which refers to the quantification of various glucocorticoids by immunoassays showing cross-reactivity with different types of glucocorticoids or related metabolites, can be measured. In this review, we describe the characteristics of the main glucocorticoids used to assess stress, as well as the main techniques and samples used for their quantification. In addition, we analyse the studies where at least two of the main glucocorticoids were measured in combination. Overall, this review points out the different behaviours of the main glucocorticoids, depending on the animal species and stressful stimuli, and shows the potential advantages that the measurement of at least two different glucocorticoid types can have for evaluating welfare.