The Effects of Bacterial Lipopolysaccharide (LPS) on Turkey Poults: Assessment of Biochemical Parameters and Histopathological Changes

Peripheral inflammation-induced changes in songbird brain gene expression: 3' mRNA transcriptomic approach

Species-specific neural inflammation can be induced by profound immune signalling from periphery to brain. Recent advances in transcriptomics offer cost-effective approaches to study this regulation. In a population of captive zebra finch (Taeniopygia guttata), we compare the differential gene expression patterns in lipopolysaccharide (LPS)-triggered peripheral inflammation revealed by RNA-seq and QuantSeq. The RNA-seq approach identified more differentially expressed genes but failed to detect any inflammatory markers. In contrast, QuantSeq results identified specific expression changes in the genes regulating inflammation. Next, we adopted QuantSeq to relate peripheral and brain transcriptomes. We identified subtle changes in the brain gene expression during the peripheral inflammation (e.g. up-regulation in AVD-like and ACOD1 expression) and detected co-structure between the peripheral and brain inflammation. Our results suggest benefits of the 3'end transcriptomics for association studies between peripheral and neural inflammation in genetically heterogeneous models and identify potential targets for the future brain research in birds.

Dietary Bacillus spp. supplementation to both sow and progenies improved post-weaning growth rate, gut function, and reduce the pro-inflammatory cytokine production in weaners challenged with Escherichia coli K88

BACKGROUND

The use of probiotics (PRO) in late gestation sow and their impact on progenies' performance during the post-weaning stage has received more attention from the researchers recently. This study aimed to analyze the effect of probiotic mixture (Bacillus subtilis and Bacillus licheniformis) on both sow and offspring's performance.

METHODS

First experiment (Exp.1) was conducted from the 100th day of gestation through to post-weaning. A total of twenty sows and their litters were assigned to one of two dietary treatments, Control (CON) based diet and PRO- CON+ 0.05% probiotic mixture. Dietary treatments were arranged in a split-plot pattern with sow and weaner treatment (CON and PRO diet) as the main and sub plot. Exp.2. E. coli challenge study was carried out two weeks after weaning with 40 piglets. Dietary treatments remained same while all pigs were orally administered with a 1.5 ml suspension of 1010 CFU of K88 strain of E. coli per ml.

RESULT

PRO group sow showed significantly decreased backfat thickness difference and body weight difference after farrowing and at the end of weaning d21. The nutrient digestibility of PRO group sows was significantly higher at the end of weaning. Moreover, piglets born from PRO group sow showed higher weaning weight and tend to increase average daily gain at the end of d21. The addition of mixed probiotic in sow and weaner diet had suppressed the production of TNF-α and interleukin-6 in E. coli challenged pigs. The phyla Firmicutes and Bacteroidetes in E. coli -challenged pigs were highly abundant while, the relative abundance of clostridium_sensu_stricto_1 at genus level was significantly reduced by the inclusion of probiotic in both the sow and weaner diet. Also, taxonomic distribution analysis showed significantly lower prevalence of Clostridium and Brachyspira and higher prevalence of Lactobacilli in E. coli-challenged pigs that were born from PRO group sow and fed CON and PRO weaner diet.

CONCLUSION

This study reveals that the inclusion of 0.05% mixed probiotics (Bacillus spp.) to both sow and their progenies diet would be more beneficial to enhance the post-weaning growth rate, gut health, and immune status of E. coli challenged pigs.

Growth and response to Escherichia coli lipopolysaccharide challenge in Lohmann LSL-Lite pullets when fed a source of omega-3 fatty acids and yeast bioactives from hatch through to 16 wk of age

Growth and response to Escherichia coli lipopolysaccharide (LPS) challenge in Lohmann LSL-Lite pullets when fed a source of omega-3 fatty acids (n-3 FA) and yeast bioactives (YB) from hatch through to 16 wk of age (woa) were investigated. Co-extruded full fat flaxseed and pulse mixture (FFF; 1:1 wt/wt) supplied n-3 FA and YB were yeast cell walls processed with β-1,3-glucan hydrolase. A total of 1,064-day-old pullets were placed in cages (19 birds/cage) and allocated to 7 diets (n = 8). The iso-caloric and iso-nitrogenous diets were control, control + 1, 3, or 5% FFF and + 0.025, 0.05, or 0.1% YB. The birds had ad libitum access to feed and water. Body weight (BW), feed intake, and lymphoid organs weight were recorded. At 15 woa, 2 pairs of pullets/cage received intravenous injection of either 1 mL of sterile saline without or with 8 mg LPS/kg BW. Injected pullets were bled, monitored for BW and cloaca temperature at time points within 168 h. Birds fed 1% FFF were heavier (P < 0.04) than birds fed other diets at 16 woa with FFF and YB exhibiting non-linear responses. Control birds had heavier (P = 0.02) thymus at 4 woa. Spleen weight increased quadratically (P < 0.05) in response to FFF at 8 and YB at 16 woa. The LPS increased cloaca temperature and altered concentration of several plasma metabolites (P < 0.05). The interaction (P < 0.05) between LPS and diet was such that control birds exhibited lower creatine kinase (CK) upon challenge with LPS relative to birds fed other diets. The LPS birds fed 1% FFF and 0.05% YB showed higher plasma albumin than non-LPS cohorts. Non-LPS birds fed control, 1 and 3% FFF had higher plasma K than LPS cohorts. In general, FFF and YB exhibited linear and quadratic effects (P < 0.05) on select plasma metabolites. In conclusion, dietary provision of n-3 FA and YB influenced pullet BW at sexual maturity, development of lymphoid organs and modulated some plasma metabolites in response to LPS.

Effects of Continuous LPS Induction on Oxidative Stress and Liver Injury in Weaned Piglets

Due to imperfections in their immune and digestive systems, weaned piglets are susceptible to invasions of the external environment and diseases, especially bacterial infections, which lead to slow growth, tissue damage, and even the death of piglets. Here, a model of weaned piglets induced by Escherichia coli lipopolysaccharide (LPS) was established to explore the effects of continuous low-dose LPS induction on the mechanism of liver injury. A total of forty-eight healthy 28-day-old weaned piglets (weight = 6.65 ± 1.19 kg) were randomly divided into two groups: the CON group and LPS group. During the experimental period of thirteen days, the LPS group was injected intraperitoneally with LPS (100 μg/kg) once per day, and the CON group was treated with the same volume of 0.9% NaCl solution. On the 1st, 5th, 9th, and 13th days, the serum and liver of the piglets were collected for the determination of serum biochemical indexes, an antioxidant capacity evaluation, and histopathological examinations. In addition, the mRNA expression levels of the TLR4 pathway and inflammatory cytokines were detected. The results showed that the activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) in the serum increased after LPS induction. The activities of total antioxidant capacity (T-AOC) and glutathione peroxidase (GSH-Px) in the serum and liver homogenate of the LPS group were lower than those of the CON group, while the malondialdehyde (MDA) content in the serum and the activities of catalase (CAT) and superoxide dismutase (SOD) in the liver of the LPS group were higher than those in the CON group. At the same time, morphological impairment of the livers occurred, including hepatocyte caryolysis, hepatocyte vacuolization, karyopycnosis, and inflammatory cell infiltration, and the mRNA expression levels of TLR4, MyD88, NF-κB, TNF-α, IL-6, and IL-10 were upregulated in the livers after LPS induction. The above results were more obvious on the 1st and 5th days of LPS induction, while the trend during the later period was not significant. It was concluded that the oxidative stress and liver injury occurred at the early stage of LPS induction, while the liver damage weakened at the later stage. The weaned piglets probably gradually developed tolerance to the endotoxin after the continuous low-dose induction of LPS.

Modulatory effect of dietary probiotic and prebiotic supplementation on growth, immuno-biochemical alterations, DNA damage, and pathological changes in E. coli-infected broiler chicks

Avian pathogenic Escherichia coli is one of the principal causes of heavy economic losses to the poultry industry. Little is known about the underlying mechanisms, particularly the potential role of immunoglobulin A and the DNA damage, involving the beneficial effects of dietary supplementation of probiotics and prebiotics in avian colibacillosis. The current study investigated the potential effects of probiotic and prebiotic dietary supplementation on E. coli-infected broiler chicks. A total of 120 1-day-old unsexed Hubbard chicks were divided into six groups: Group 1 was considered as a negative control; Group 2 was supplemented with 1 g/kg feed of Lactobacillus plantarum; Group 3 was supplemented with amylase enzyme; Group 4 served as a positive control infected orally by E. coli O78; Group 5 was supplemented with L. plantarum from 1-day-old chicken and then infected orally with E. coli O78; and Group 6 was supplemented with amylase enzyme from 1-day old chicken and then infected orally with E. coli O78. For all examined groups, the experimental period lasted for 42 days. The E. coli-infected group revealed a decrease in body performance parameters with a significant increase in the liver enzymes and renal function tests. The same group recorded a significant decrease in serum total proteins, albumins, and globulins, and the alteration of immunological parameters, antioxidant enzymes, oxidative stress parameters, and comet assay revealed highly damaged DNA in the liver and the intestine. By histopathological examination, a series of histopathological changes in the liver, the kidney, and the intestine were observed. The infected chick pretreated with probiotics or prebiotics demonstrated an improvement in body performance parameters besides a significant decrease in the hepatic enzymes and renal function tests. We noticed that, in treated groups, there was a significant increase in serum total proteins in the serum albumin and globulin levels, immunological parameters, and antioxidant enzymes. Furthermore, DNA damage and histopathological changes within hepatic, renal, and intestinal tissues were markedly diminished in the treated groups compared with the infected group. We concluded that the adverse effects of E. coli could be modulated through the chemopreventive administration of probiotics and prebiotics.