Health Status Of Pigs Research Articles

HEMATOLOGICAL AND SERUM BIOCHEMICAL PARAMETERS OF WEANED PIGS FED MAIZE COB-CASSAVA PEEL MIXTURE AS PARTIAL REPLACEMENT FOR MAIZE

This study was carried out to investigate the haematological and serum biochemical parameters of weaned pigs fed maize cob-cassava peel mixture as partial replacement for maize. A total of 36 crossbreed male piglets with initial body weight (6.07±0.02 kg) of about 7-8 weeks’ old were randomly distributed into four groups of nine animals per treatment. Each treatment was further divided into three replicates consisting of three pigs in a completely randomized design. Pigs in treatment 1 were fed 0 % maize cob-cassava peel mixture (CPMCM) while CPMCM was used to replace maize at 10 % (T2), 20 % (T3) and 30 % (T3). Phytochemical evaluation of CPMCM revealed the presence of alkaloids (19.10 mg/kg), tannins (8.17 mg/kg), saponins (9.11 mg/kg), cyanide (16.50 mg/kg), flavonoids (12.86 mg/kg) and phenol (7.72 mg/kg). All the haematological parameters: red blood cell, pack cell volume, haemoglobin, mean corpuscular haemoglobin, mean corpuscular volume, mean corpuscular haemoglobin concentration, white blood cell, monocytes, basophils and lymphocytes were significantly (P<0.05) influenced by the treatment except for platelet values (P>0.05). Similarly, total protein, total bilirubin and gluscose levels were significantly different (P<0.05) among the treatments except for cholesterol, urea, creatinine, activities of alkaline phosphatase, alanine transaminase and aspartate transaminase were not influenced by the treatment (P>0.05). However, values were within the normal range for heathy weaner pigs. It was concluded that CPMCM can be used to partially replace maize up to 30 % without having any negative effect on the health status of pigs.

Online feeding behavior monitoring of individual group-housed grow-finish pigs using a low-frequency RFID electronic feeding system.

Early identification of animals in need of management intervention is critical to maximize animal health and welfare and minimize issues with productivity. Feeding behavior, captured by automated feeding systems, can be used to monitor the health and welfare status of individual pigs. Here, we present a framework for monitoring feeding behavior of grow-finish pigs in real time, using a low-frequency radio frequency identification (RFID) system. Using historical data, an autoregressive linear model for predicting daily time at the feeder was developed and utilized to detect anomalous decreases in feeding behavior associated with health status of the pig. A total of 2,826 pigs were individually monitored with our warning system over the entire grow-finish period, and health warnings were compared to caretaker diagnoses. The system detected 55.7% of the caretaker diagnoses, and on average these events were detected 2.8 d earlier than diagnosis by the caretaker. High numbers of potentially spurious health warnings, generated by the system, can be partly explained by the lack of a reliable and repeatable gold standard reference data set. Results from this work provide a solid basis for monitoring individual animals, but further improvements to the system are necessary for practical implementation.

Investigation of porcine circovirus type 2 and porcine circovirus type 3 infections based on dual TaqMan fluorescent quantitative PCR method and genetic evolutionary analysis of these two viruses.

Porcine circovirus type 2 (PCV2) is the pathogen of Porcine Circovirus Associated Diseases. Porcine circovirus type 3 (PCV3) is a novel porcine circovirus associated with porcine dermatitis and nephropathy syndrome (PDNS) and reproductive failure. PCV2 is clearly pathogenic, while the pathogenicity of PCV3 remains controversial, so it is crucial to monitor the prevalence of PCV2 and PCV3 in healthy and diseased pigs to investigate the effects of PCV3 and PCV2 on the health status of pigs. Here, we developed a PCV2 and PCV3 dual TaqMan quantitative PCR (qPCR) method to test samples from healthy and diseased pigs, to clarify the differences in the positive rates and viral copy numbers of PCV2 and PCV3, and to analyze the genetic evolution and molecular characterization of the viral genomes obtained with sequence alignment and phylogenetic analysis, homology and structural analysis of Cap proteins, and selection pressure analysis. We successfully established a dual TaqMan qPCR method for PCV2 and PCV3 with good repeatability, specificity and sensitivity. In total, 1,385 samples from 15 Chinese provinces were tested with the established qPCR. The total positive rates were 37.47% for PCV3 and 57.95% for PCV2, and the coinfection rate for was 25.49%. The positive rates of PCV3 and PCV2 in 372 healthy pigs were 15.05 and 69.89%, respectively, and the coinfection rate was 12.90%. The positive rates of PCV3 and PCV2 in 246 diseased pigs were 55.69 and 83.33%, respectively, and the coinfection rate was 47.97%. Eighteen PCV3 genomes and 64 PCV2 genomes were identified, including nine each of the PCV3a-1 and PCV3b genotypes, eight of PCV2a, 16 of PCV2b, and 40 of PCV2d. The amino acid identity within the PCV3 Cap proteins was 94.00-100.0%, whereas the PCV2 Cap proteins showed an identity of 81.30-100.0%. PCV3 Cap was most variable at amino acid sites 24, 27, 77, 104 and 150, whereas PCV2 Cap had 10-13 unique sites of variation between genotypes. These results clarify the prevalence and variations of PCV2 and PCV3 in healthy and diseased pigs, which will provide a basis for the prevention and control of the two viral infections.

Haematological and Serum Biochemical Parameters of Weaned Pigs Fed Maize Cob-Cassava Peel Mixture as Partial Replacement for Maize


 
 
 This study was carried out to investigate the haematological and serum biochemical parameters of weaned pigs fed maize cob-cassava peel mixture as partial replacement for maize. A total of 36 crossbreed male piglets with initial body weight (6.07±0.02 kg) of about 7-8 weeks’ old were randomly distributed into four groups of nine animals per treatment. Each treatment was further divided into three replicates consisting of three pigs in a completely randomized design. Pigs in treatment 1 were fed 0 % maize cob-cassava peel mixture (CPMCM) while CPMCM was used to replace maize at 10 % (T2), 20 % (T3) and 30 % (T3). Phytochemical evaluation of CPMCM revealed the presence of alkaloids (19.10 mg/kg), tannins (8.17 mg/kg), saponins (9.11 mg/kg), cyanide (16.50 mg/kg), flavonoids (12.86 mg/kg) and phenol (7.72 mg/kg). All the haematological parameters: red blood cell, pack cell volume, haemoglobin, mean corpuscular haemoglobin, mean corpuscular volume, mean corpuscular haemoglobin concentration, white blood cell, monocytes, basophils and lymphocytes were significantly (P<0.05) influenced by the treatment except for platelet values (P>0.05). Similarly, total protein, total bilirubin and gluscose levels were significantly different (P<0.05) among the treatments except for cholesterol, urea, creatinine, activities of alkaline phosphatase, alanine transaminase and aspartate transaminase were not influenced by the treatment (P>0.05). However, values were within the normal range for heathy weaner pigs. It was concluded that CPMCM can be used to partially replace maize up to 30 % without having any negative effect on the health status of pigs.
 
 

Monitoring using artificial intelligence reveals critical links between housing conditions and respiratory health in pigs

Respiratory disease is the most significant issue in the pig industry and leads to high mortality and reduced growth rates. Housing conditions are crucial for maintaining the health and welfare of animals to optimize growth rates. This study aimed to evaluate the respiratory health status of pigs raised in different housing conditions using artificial intelligence (AI) technology and to determine the relationships between respiratory health and environmental factors. Eighty growing pigs (Largewhite × Landrace) × Duroc) were randomly distributed into two housing conditions: the control group, which had normal housing conditions, and the treatment group, which had poor housing conditions. A two-sample t test was performed to compare the groups, and a cross-correlation analysis was conducted to determine associations between respiratory health and days of exposure to environmental factors. The results show significant (p < 0.001) lower incidence of respiratory health status along with a significant (p < 0.001) greater frequency of coughing in pigs raised under poor housing conditions. Respiratory health is negatively associated with high exposure to temperature, relative humidity, and CO2 at lags 0 (R = -0.873, -0.887, and -0.869, respectively), -1 (R = -0.708, -0.742, and -0.705, respectively), and -2 (R = -0.545, -0.590, and -0.599, respectively). Furthermore, respiratory health was negatively associated with high exposure to NH3 (R = -0.420) at lag 0. In conclusion, AI technology is an effective tool for monitoring respiratory health. However, further evaluation and calibration of the alarm system threshold are recommended. These findings suggest that maintaining proper control of environmental factors can help prevent respiratory diseases in pigs.

Prevalence of Streptococcus suis serotype 2 isolated from pigs: A systematic review and meta-analysis.

Among Streptococcus suis serotypes, S. suis serotype 2 is the most significant serotype that causes serious diseases in pigs and humans worldwide. The present study aimed to estimate the global prevalence of S. suis serotype 2 isolated from pigs, determine its trend, and explore the factors associated with this serotype. We retrieved relevant published studies from PubMed, Scopus, and the Web of Science. The retrieved citations were screened for possible inclusion. Relevant data were then extracted from the included studies. The random-effects model was used for all meta-analyses. A subgroup meta-analysis was used to assess the heterogeneity of the prevalence for four characteristics (continents, sampling organs, reporting unit, and pig's health status). A cumulative meta-analysis was performed to determine the cumulative prevalence over time. Meta-regression analysis was used to determine the trend of pooled prevalence of S. suis serotype 2 over time. Of 600 articles retrieved, 36 studies comprising a total sample size of 6939 isolates or samples from 16 countries of four continents were included for meta-analysis. The pooled prevalence of S. suis serotype 2 isolated from pigs was 13.6% (95% confidence interval [CI], 10.7%-17.1%), with high heterogeneity among the included studies (Cochran's Q, 431.6; p < 0.001; I2 = 91.9%; Table-1). No statistical significance was observed among subgroups of the four characteristics examined. However, the pooled prevalence of S. suis serotype 2 was as high as 16.0% (95% CI, 12.5%-20.3%; n = 16) in diseased pigs compared with 9.9% (95% CI, 5.6%-17.0%; n = 15) in healthy pigs. The pooled prevalence of S. suis serotype 2 isolated from pigs did not significantly decrease over time [regression coefficient = -0.020 (95% CI, 0.046-0.006, p = 0.139)]. The pooled prevalence of S. suis serotype 2 isolated from pigs fluctuated slightly between 13.2% and 17.8% from 2007 to 2023, although the pooled prevalence gradually decreased from 30.6% in 1987 to over 20% in 2003. The global prevalence of S. suis serotype 2 isolated from pigs was estimated to be 13.6% (approximately 10% in healthy pigs and around 16% in diseased pigs). S. suis serotype 2 isolated from pigs did not change significantly over time. These results indicate that S. suis serotype 2 remains a problem for the pig industry and poses a threat to human health.

In vitro evaluation of the immunomodulatory and wakame assimilation properties of Lactiplantibacillus plantarum strains from swine milk.

The emergence and spread of antibiotic resistance threat forced to explore alternative strategies for improving the resistance to pathogens in livestock production. Probiotic lactic acid bacteria represent an alternative for this objective. In this study, seven Lactiplantibacillus plantarum strains from porcine colostrum and milk were isolated, identified and characterized in terms of their abilities to modulate immunity in porcine intestinal epithelial (PIE) cells. Then, two potential immunoregulatory strains were studied in terms of their ability to utilize and grow in wakame (Undaria pinnafida). Isolates were identified by 16S rRNA gene and evaluated by studying their interaction with PIE cells. The expressions of peptidoglycan recognition proteins (PGRPs), nucleotide-binding oligomerization domain (NODs), host defense peptides (pBD), and type I interferons (IFNs) were evaluated by RT-qPCR. The strain 4M4417 showed a remarkable capacity to differentially regulate the expression of PGRP1, PGRP3, NOD1, NOD2, and pBD1 in PIE cells. On the other hand, the strain 4M4326 was the most efficient to improve the expression of IFN-α and IFN-β in PIE cells challenged with poly (I:C). Both L. plantarum 4M4326 and 4M4417 were characterized in terms of their ability to utilize wakame. Results demonstrated that both strains efficiently grew in wakame-based broth. Our results suggest that L. planatrum 4M4326 and 4M4417 are interesting candidates to develop immunomodulatory feeds based on wakame utilization. These new immunosynbiotic feeds could help to reduce severity of intestinal infections and improve immune health status in pigs.

A CNN-SVM Study Based on the Fusion of Spectrogram and Thermal Imaging Heterogeneous Features for Pig Cough Recognition in Field Situation

Accurate identification of pig cough is essential for comprehensive monitoring and diagnosis of the respiratory health status of pigs. It contributes to stress-free animal health management, reduces pig mortality and improves the economics of farming. Creating a representative multisource signal signature of pig cough is a critical step in achieving automatic recognition of pig cough. For this reason, in this paper, we propose a feature fusion classification method that combines the spectrogram deep features and thermal image deep features to be fed into a support vector machine (SVM) classifier to accomplish cough classification. First, we use a time–frequency transformation algorithm to convert a one-dimensional cough sound signal into a two-dimensional acoustic spectrogram. Then, the corresponding heterogeneous deep features are extracted from the cough spectrogram and thermal image by fine-tuning Lenet-5 and a customized CoughRNet shallow convolutional neural network. Finally, we employ an early fusion technique to align and splice the extracted heterogeneous deep features and feed them into an SVM for the automatic classification task of pig cough. Our study evaluates the classification performance, recognition speed and model size of the proposed deep feature fusion classification network with satisfactory results. Experimental results show that the method achieves 99.77% accuracy in pig cough recognition. This further demonstrates the effectiveness of combining abstract heterogeneous sound and thermal image deep features as a method for automated detection of pig respiratory health.

Fecal microbial and metabolic characteristics of swine from birth to market.

Recently, the research on pig intestinal microbiota has become a hot topic in the field of animal husbandry. There are few articles describing the dynamic changes of porcine fecal microbiota and metabolites at different time points from birth to market. In the present study, 381 fecal samples were collected from 633 commercial pigs at 7 time points, including the 1st day, the 10th day, the 25th day, the 45th day, the 70th day, the 120th day, and the 180th day after the birth of swine, were used for microbiome analysis by Illumina MiSeq sequencing methods while 131 fecal samples from 3 time points, the 10th day, the 25th day, and 70th day after birth, were used for metabolome analysis by LC-MS methods. For the microbiome analysis, the fecal microbial richness increased over time from day 1 to 180 and the β-diversity of fecal microbiota was separated significantly at different time points. Firmicutes were the main phyla from day 10 to 180, followed by Bacteroides. The abundance of Lactobacillus increased significantly on day 120 compared with the previous 4 time points. From day 120 to day 180, the main porcine fecal microbes were Lactobacillus, Clostridium_sensu_stricto_1, Terrisporobacter and Streptococcus. Clostridium_sensu_stricto_1 and Terrisporobacter increased over time, while Lactobacillus, Escherichia-Shigella, Lachnoclostridium decreased with the time according to the heatmap, which showed the increase or decrease in microbial abundance over time. For the metabolome analysis, the PLS-DA plot could clearly distinguish porcine fecal metabolites on day 10, 25, and 70. The most different metabolic pathways of the 3 time points were Tryptophan metabolism, Sphingolipid signaling pathway, Protein digestion and absorption. Some metabolites increased significantly over time, such as Sucrose, L-Arginine, Indole, 2,3-Pyridinedicarboxylic acid and so on, while D-Maltose, L-2-Aminoadipic acid, 2,6-diaminohexanoic acid, L-Proline were opposite. The correlation between fecal metabolites and microbiota revealed that the microbes with an increasing trend were positively correlated with the metabolites affecting the tryptophan metabolic pathway from the overall trend, while the microbes with a decreasing trend were opposite. In addition, the microbes with an increasing trend were negatively correlated with the metabolites affecting the lysine pathway. In conclusion, this study elucidated the dynamic changes of porcine fecal microbiota and metabolites at different stages from birth to market, which may provide a reference for a comprehensive understanding of the intestinal health status of pigs at different growth stages.

Influence of Factors on the gastrointestinal microbiota of Pigs

A complete understanding of the dynamic distribution of the intestinal microbiota in pigs is essential because microorganisms play a fundamental role in physiological processes, immunity, and nutrient metabolism by the macroorganism. Disruption of the gut microbiome can cause inflammation, oxidative stress, and a cytokine storm. Gut microbiome dysfunction can be caused by short-term or long-term (environmental, nutritional, and stress) factors. The microbial ecosystem of the intestine is fundamental for the pig's proper nutrition, and physiological and immunological functions. However, the composition and function of a healthy microbial ecosystem have yet to be qualitatively and quantitatively determined to be used as a tool to maximize animal health and performance. As efforts are made to reduce the use of antibiotics in pig farming, the ability of the gut microbiota to increase disease resistance must be recognized. Generally, the genera Bacteroides, Escherichia, Clostridium, Lactobacillus, Fusobacterium, and Prevotella dominate in pre-weaning piglets. Then Prevotella and Aneriacter become the dominant genera, with Fusobacterium, Lactobacillus and Miscellaneous as relative minors in post-weaning piglets. Specific genera of bacteria, including Bacteroides, Prevotella, and Lactobacillus, can be detected in more than 90 % of pigs and three enterotypes – identified in animals of the same species but of different ages. This suggests the presence of a “core” microbiota in the gut of healthy pigs that may be a potential target for nutritional or health regulation. The scientists' scientific data help to determine the “optimal” gut microbial profile for evaluating or improving the performance and health status of pigs at different stages of growth. Although external and stochastic factors contribute to the individuality of the microbiota, the fundamental principles governing how environmental factors and host genetic factors combine to shape this complex ecosystem are largely unknown and require systematic study.

Supplementing turmeric rhizome powder in growing Andaman local pigs: a conflated approach for therapy evaluation

This paper examined the pluripotent effect of supplementation of turmeric rhizome powder (TRP) (Curcuma longa) in growing Andaman local pigs. A total of 48 pigs were randomly allotted into four groups and fed diets containing TRP at 4 concentrations, that is, 0 (control group), 0.05 (treatment 1), 0.1 (treatment 2), and 0.2% (treatment 3) for 30 days. The mean body weight of pigs supplemented with 0.1% and 0.2% TRP was significantly higher than that of the control group (41.66 ± 0.44, 42.59 ± 0.33 vs 40.38 ± 0.30 kg; p ≤ 0.05) which indicated the effect of TRP as growth enhancer. A significant (p ≤ 0.05) decrease in serum concentration of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) was recorded in supplemented groups as compared to the control group. Creatinine kinase (U/l) decreased in all the treatment groups as compared to the control group. Total cholesterol, triglyceride, and low-density lipoprotein cholesterol decreased significantly after supplementation with 0.1% and 0.2% TRP in comparison to the control group. However, there was marked increase in high-density lipoprotein cholesterol (mg/dl) in all TRP-supplemented groups than the control group (27.67 ± 0.60 in T1, 32.76 ± 0.32 in T2, and 34.58 ± 0.37 in T3 vs. 23.73 ± 0.69 in control; p ≤ 0.05). Further, there was increase in antioxidant profile after TRP supplementation. Anti-inflammatory potentiality of TRP could also be appreciated since TRP supplementation downregulated (p ≤ 0.05) expression of IL-6, IL-1β, and IFN-γ. Therefore, we perceive that this conflated approach is an example of its own kind to focus on modification of health status of pigs for more productivity and augmentation of immune response.

Weanling pigs consume more feed if hybrid rye replaces corn in diets, but average daily gain and fecal scores are not impacted by hybrid rye.

An experiment was conducted to test the hypothesis that growth performance and health status of pigs will not be reduced if hybrid rye is included in diets at the expense of corn during the initial 5 wk post-weaning. A total of 128 weanling pigs (5.6 ± 0.5 kg) were randomly allotted to 32 pens and 4 dietary treatments. Pigs were fed experimental diets for 35 d in three phases with days 1 to 7 being phase 1, days 8 to 21 being phase 2, and days 22 to 35 being phase 3. Within each phase, a control diet primarily based on corn and soybean meal was formulated, and three additional diets were formulated by including 8.0, 16.0, or 24.0% (phase 1), 16.0, 32.0, or 48.0% (phase 2), and 20.0, 40.0, or 60.3% (phase 3) hybrid rye in the diet at the expense of corn. Pig weights were recorded at the start and conclusion of each phase, fecal scores were visually assessed every other day on a pen basis, and blood samples were obtained from 1 pig per pen on days 21 and 35. Results indicated that average daily gain (ADG) in phase 1 increased (linear, P < 0.05) as the inclusion of hybrid rye increased, but no other differences in ADG were observed. Average daily feed intake linearly increased in phase 1, phase 3, and overall (P < 0.05) as hybrid rye inclusion increased in the diets, and gain:feed was negatively impacted by the inclusion of hybrid rye in the diet (phase 1, linear, P < 0.05; phases 2, 3, and overall, quadratic, P < 0.05). No differences in average fecal scores or diarrhea incidence were observed. On days 21 and 35, blood urea N increased (linear, P < 0.05) as hybrid rye increased in the diets; and on day 21, serum total protein also increased (linear, P < 0.05) with increasing hybrid rye inclusion in the diet. Mean blood hemoglobin concentration on day 35 increased and then decreased as hybrid rye inclusion increased (quadratic, P < 0.05). On day 21, interleukin (IL) 2 and IL 10 decreased and then increased (quadratic, P < 0.05) as hybrid rye inclusion increased. On day 35, IL 8 and IL 12 increased and then decreased (quadratic, P < 0.05) and interferon-gamma decreased and then increased (quadratic, P < 0.01) as hybrid rye inclusion increased. In conclusion, the ADG of pigs was not different among treatments, but at the highest hybrid rye inclusion level, pigs consumed more feed than if corn was fed and gain:feed was reduced with increasing hybrid rye in diets. Differences in blood serum cytokines indicate the immune system was affected differently when hybrid rye instead of corn was fed.

Combined spectral and speech features for pig speech recognition.

The sound of the pig is one of its important signs, which can reflect various states such as hunger, pain or emotional state, and directly indicates the growth and health status of the pig. Existing speech recognition methods usually start with spectral features. The use of spectrograms to achieve classification of different speech sounds, while working well, may not be the best approach for solving such tasks with single-dimensional feature input. Based on the above assumptions, in order to more accurately grasp the situation of pigs and take timely measures to ensure the health status of pigs, this paper proposes a pig sound classification method based on the dual role of signal spectrum and speech. Spectrograms can visualize information about the characteristics of the sound under different time periods. The audio data are introduced, and the spectrogram features of the model input as well as the audio time-domain features are complemented with each other and passed into a pre-designed parallel network structure. The network model with the best results and the classifier were selected for combination. An accuracy of 93.39% was achieved on the pig speech classification task, while the AUC also reached 0.99163, demonstrating the superiority of the method. This study contributes to the direction of computer vision and acoustics by recognizing the sound of pigs. In addition, a total of 4,000 pig sound datasets in four categories are established in this paper to provide a research basis for later research scholars.

Research on Improved DenseNets Pig Cough Sound Recognition Model Based on SENets

In order to real-time monitor the health status of pigs in the process of breeding and to achieve the purpose of early warning of swine respiratory diseases, the SE-DenseNet-121 recognition model was established to recognize pig cough sounds. The 13-dimensional MFCC, ΔMFCC and Δ2MFCC were transverse spliced to obtain six groups of parameters that could reflect the static, dynamic and mixed characteristics of pig sound signals respectively, and the DenseNet-121 recognition model was used to compare the performance of the six sets of parameters to obtain the optimal set of parameters. The DenseNet-121 recognition model was improved by using the SENets attention module to enhance the recognition model’s ability to extract effective features from the pig sound signals. The results showed that the optimal set of parameters was the 26-dimensional MFCC + ΔMFCC, and the rate of recognition accuracy, recall, precision and F1 score of the SE-DenseNet-121 recognition model for pig cough sounds were 93.8%, 98.6%, 97% and 97.8%, respectively. The above results can be used to develop a pig cough sound recognition system for early warning of pig respiratory diseases.

Formulating Diets for Improved Health Status of Pigs: Current Knowledge and Perspectives.

Simple SummaryToday’s swine production systems are mostly intensive, and pigs are continuously exposed to pathogens and immune stimulatory antigens that may negatively impact productivity. It is known that immune system stimulation may reduce appetite, growth, and nutrient use efficiency compared to healthy animals. On the other hand, there is progressive pressure towards the reduction in antibiotic usage in livestock production, which highlights the need for furthering our understanding of the relationship between nutrition and the immune response. Swine nutritionists will need to consider the role of nutrition on health in order to develop programs that support production and robustness of pigs under a variety of stressful conditions. Among the nutritional strategies whose utilization may directly impact on the immune status of pigs, feeding low protein, amino acid-supplemented diets, supplementation of functional amino acids, dietary fiber level and source, diet complexity, organic acids, and plant secondary metabolites are at the forefront. As such, this review will discuss the impact of immune status on swine production and the interaction between nutrients and animal health, focusing on the roles of each nutritional strategy during times of immune challenge.Our understanding of nutrition has been evolving to support both performance and immune status of pigs, particularly in disease-challenged animals which experience repartitioning of nutrients from growth towards the immune response. In this sense, it is critical to understand how stress may impact nutrient metabolism and the effects of nutritional interventions able to modulate organ (e.g., gastrointestinal tract) functionality and health. This will be pivotal in the development of effective diet formulation strategies in the context of improved animal performance and health. Therefore, this review will address qualitative and quantitative effects of immune system stimulation on voluntary feed intake and growth performance measurements in pigs. Due to the known repartitioning of nutrients, the effects of stimulating the immune system on nutrient requirements, stratified according to different challenge models, will be explored. Finally, different nutritional strategies (i.e., low protein, amino acid-supplemented diets; functional amino acid supplementation; dietary fiber level and source; diet complexity; organic acids; plant secondary metabolites) will be presented and discussed in the context of their possible role in enhancing the immune response and animal performance.

Proteomic and immunoproteomic insights into the exoproteome of Actinobacillus pleuropneumoniae, the causative agent of porcine pleuropneumonia

Porcine pleuropneumonia caused by Actinobacillus pleuropneumoniae affects pig health status and the swine industry worldwide. Despite the extensive number of studies focused on A. pleuropneumoniae infection and vaccine development, a thorough analysis of the A. pleuropneumoniae exoproteome is still missing. Using a complementary approach of quantitative proteomics and immunoproteomics we gained an in-depth insight into the A. pleuropneumoniae serotype 2 exoproteome, which provides the basis for future functional studies. Label-free liquid chromatography-tandem mass spectrometry (LC-MS/MS) revealed 593 exoproteins, of which 104 were predicted to be virulence factors. The RTX toxins ApxIIA and ApxIIIA -were found to be the most abundant proteins in the A. pleuropneumoniae serotype 2 exoproteome. Furthermore, the ApxIVA toxin was one of the proteins showing the highest abundance, although ApxIVA is commonly assumed to be expressed exclusively in vivo. Our study revealed several antigens, including proteins with moonlight functions, such as the elongation factor (EF)-Tu, and proteins linked to specific metabolic traits, such as the maltodextrin-binding protein MalE, that warrant future functional characterization and might present potential targets for novel therapeutics and vaccines. Our Ig-classes specific serological proteome analysis (SERPA) approach allowed us to explore the development of the host humoral immune response over the course of the infection. These SERPAs pinpointed proteins that might play a key role in virulence and persistence and showed that the immune response to the different Apx toxins is distinct. For instance, our results indicate that the ApxIIIA toxin has properties of a thymus-independent antigen, which should be studied in more detail.

High sensitivity, fast response and anti-interference crack-based reduced graphene oxide strain sensor for pig acoustic recognition

With the development of precision pig industry and the growing demands for pork products, it is of great significance to monitor the health of pigs. The reported detection methods suffer harmful, time-consuming, complex and expensive. Acoustic detection is a simple and effective contactless method to judge the health status of pigs. Strain sensor as an important contactless method has attracted wide research interest in acoustic detection. However, most strain sensors cannot accurately detect pig sounds due to their low sensitivity, slow response, and susceptibility to interference. In this work, a crack-based rGO strain sensor is proposed and exhibits unique “half-open, half-close” microstructures. The strain changes the crack gaps, resulting in the resistance of sensor increases. The sensor exhibits high sensitivity and fast response in a wide frequency range from 110 Hz to 5000 Hz and its ΔR/R0 increases monotonically with increasing acoustic intensity. In addition, the rGO sensor is directional and thus has anti-interference ability to noise. The rGO sensor is applied for pig acoustic recognition and the measured results agree well with the original audios. In conclusion, the crack-based rGO strain sensor with high sensitivity, fast response and anti-interference shows great potential for pig acoustic recognition and its detected results can provide a reference for pig health monitoring.

Effects of a multi-strain Bacillus subtilis-based direct-fed microbial on immunity markers and intestinal morphology in diets fed to weanling pigs.

The objective of this experiment was to evaluate the effects of a multi-strain Bacillus subtilis-based direct-fed microbial (DFM) on nursery pig health as indicated by intestinal mucosal and blood plasma immunological markers and intestinal morphology. Eighty pigs, of equal number of barrows and gilts (initial BW: 7.0 ± 0.60 kg), weaned at 21 ± 1 d of age were randomly allotted to sixteen pens, with five pigs per pen. Two dietary treatments were implemented, a basal control (CON) and a basal control plus DFM (CDFM). Both diets were corn, soybean meal, and distillers dried grains based and were formulated to meet or exceed all nutritional requirements (NRC, 2012) and manufactured on site. Diets were fed for 42 d. On d 21 and 42 of the experiment, one pig per pen was randomly selected and euthanized, with equal number of males and females represented. Blood samples were collected prior to euthanasia for assessment of plasma concentrations of immunoglobulin A (IgA) and intestinal fatty acid binding protein. Segments of the gastrointestinal tract including duodenum, jejunum, ileum, ascending and distal colon were removed for analysis of intestinal morphology, and levels of interleukin 6, interleukin 10 (IL-10), and tumor necrosis factor alpha. Jejunal villus height was greater in the CDFM pigs as compared with CON pigs (P = 0.02) and ascending colon crypt depth tended to be greater on d 21 (P = 0.10). Compared to CON, CDFM significantly increased overall plasma IgA (P = 0.03) (0.58 vs. 0.73 0.05 mg/mL, respectively), while it tended to increase plasma IgA (P = 0.06) on d 21 (0.34 vs. 0.54 ± 0.07 mg/mL, respectively) and tended to increase overall IL-10 (P = 0.10) in the jejunum (113 vs. 195 ± 35 pg/mL, respectively). Addition of a multi-strain Bacillus subtilis-based DFM may have an early benefit to nursery pig health status, observed through specific changes in morphology and both systemic and localized immunological markers.

Sanitary Conditions on the Farm Alters Fecal Metabolite Profile in Growing Pigs.

The aim of this study was to use fecal metabolite profiling to evaluate the effects of contrasting sanitary conditions and the associated subclinical health status of pigs. We analyzed fecal metabolite profiles by nuclear magnetic resonance (1H NMR) from pigs aged 14 and 22 weeks. Pigs kept under low and high sanitary conditions differed in fecal metabolites related to the degradation of dietary starch, metabolism of the gut microbiome, and degradation of components of animal (host) origin. The metabolites that differed significantly (FDR < 0.1) were from metabolic processes involved in either maintaining nutrient digestive capacity, including purine metabolism, energy metabolism, bile acid breakdown and recycling, or immune system metabolism. The results show that the fecal metabolite profiles reflect the sanitary conditions under which the pigs are kept. The fecal metabolite profiles closely resembled the profiles of metabolites found in the colon of pigs. Fecal valerate and kynurenic acid could potentially be used as “non-invasive” biomarkers of immune or inflammatory status that could form the basis for monitoring subclinical health status in pigs.

Performance, carcass characteristics, and health parameters of growing and finishing pigs fed with diets supplemented with isoquinoline alkaloids and essential oils

The goal of this study was to evaluate, in a commercial herd, the use of isoquinoline alkaloids and carvacrol versus a preventive antibiotic program, such as feed additives, on the performance, carcass traits, and health status of pigs in the growing and finishing phase. There were 576 PIC immunocastrated males and females, at 70 days of age and 28.429 ± 2.302 kg of initial weight used. The experimental design was a 4 × 2 factorial randomized block, with four preventive programs, two sexes, and six repetitions per treatment (the pen with 12 animals of the same sex was the replicate). The treatments were T1 (positive control program with antibiotic shocks at preventive level), T2 (negative control with the absence of antibiotics as a growth promoter or as preventive), T3 (isoquinoline alkaloids at 100 to 150 g ton-1), T4 (isoquinoline alkaloids at 90 g ton-1 + carvacrol essential oil at 1 kg ton-1). T1 and T3 presented higher daily feed intakes, followed by T2, and T4 showed the worst feed consumption (P &lt; 0.05). T1 showed higher daily weight gain compared to T4 (P &lt; 0.05), without differences between T2 and T3. T2 showed better feed conversion than T1 and T3, but it was similar to T4. There were no effects of the treatments on the carcass traits. Intestinal crypt hyperplasia and crypt abscesses (lesions caused by Lawsonia intracellularis) were significantly higher for T2 and T3 compared to T1, which was similar to T4. T2 presented the highest carcass condemnation at slaughter (7%), differing (P &lt; 0.05) from T1, T3, and T4 (1, 2, and 3%, respectively). Isoquinoline alkaloids are an alternative for antibiotic-free diets for pigs in the growing and finishing phase, preserving the performance and carcass indices and minimizing sanitary carcass condemnations at the slaughterhouse.