Effects of dietary turmeric (Curcuma longa) on innate and acquired immune responses in broiler chicken.

One of the most desired treatments to combat stress and inflammation with minimal adverse effects in large bird populations is food additives. This study investigated the effects of dietary turmeric (Curcuma longa) on the level of serum amyloid A (SAA) as an indicator for acute phase response and antibody titer to Newcastle vaccine as an indicator for humoral immune response. A total of 300 Ross broiler chickens were assigned to five dietary groups. Two treatments received basal diets supplemented with different amount of turmeric (250 and 500 mg/kg). One group received aspirin (ASA; 250 mg/L) and one group aspirin-vitamin C (ASA; 250 mg/L + Ascorbic acid; 20 mg/L) in drinking water. There was one control group that received no feeding additives. The levels of SAA and humoral antibody response to Newcastle vaccine were measured during the entire production period. Turmeric administration significantly decreased the serum SAA concentrations after 2 weeks of treatment and later. It also significantly reduced SAA elevation due to the vaccinations on day 17 but not on day 28. After the second vaccination (d 19) ELISA titer in all treatment groups was higher than control group. Significant effect of dietary turmeric on body weight was also found at week 3 and later ages. Administration of 250 mg turmeric per kg diet is recommended for broiler chickens. It is concluded that turmeric is beneficial to minimize inflammatory effects of vaccination in commercial broiler chickens. Turmeric prevents and reduces stress and negative effects of inflammation and stimulates growth performance of broiler chickens.

Transcriptome based analysis of apoptosis genes in chickens co-infected with avian infectious bronchitis virus and pathogenic Escherichia coli.

BACKGROUND AND OBJECTIVES: Infection with Infectious bronchitis virus (IBV) and avian pathogenic Escherichia coli (APEC) is an important respiratory infection worldwide. Apoptosis is a physiological process of cell death that occurs as part of normal development and responds to a variety of physiological and pathophysiological stimuli. The identification of molecular mechanisms of action or inaction of key apoptotic proteins is important. This study aimed to investigate apoptotic related genes in the trachea tissue of infected (IBV variant 2, and APEC serotype O78: K80) SPF chickens group compared to the control group. MATERIALS AND METHODS: Forty SPF chickens was divided into 2 groups. Differential transcriptional profile in the infected SPF chickens trachea tissue was compared to those of control group in the early stage of infection by Illumina RNA-seq technique paired-end and strand-specific sequencing. Differentially expressed genes (DEGs) of transcriptome profiling of the trachea from the infected group were identified. Gene ontology category, KEGG pathway, and STRING analysis were analyzed to identify relationships among differentially expressed genes. RESULTS: Twenty-eight apoptotic genes were identified. They consisted of six pathways related to cell death: the extrinsic pathway, intrinsic pathway, endoplasmic reticulum stress pathway, MAPK signaling pathway, and cell death by NFkB and activates mTOR pathway and some regulator and apoptosis inhibitors. CONCLUSION: All of the apoptotic genes in our study were up-regulated. Among these genes, the more fold change value was for TRADD and BCL2A1 genes, and the less fold change value was for MAP3K14, NFKB1, PIK3CB, and ITPR2 genes.

Molecular characterization of infectious bronchitis virus based on RNA-dependent RNA polymerase gene.

Extensive rate of variations in the S1 gene (spike glycoprotein subunit gene) of infectious bronchitis virus (IBV) causes challenges for clinicians in counting variants for differentiation of infected from vaccinated birds and addressing the variants of unknown significance. This study investigated the possibility of using an RNA-dependent RNA polymerase gene (RdRp) as a target for molecular characterization of IBV strains in Iran. Trachea samples were collected from commercial broiler flocks (n = 52) showing respiratory syndrome. Specific PCR primers were designed for a variable region located in the RdRp gene flanked by highly conserved regions. Reverse transcriptase PCR followed by sequence analysis identified eight IBV variants, with an overall prevalence of 44.2%. Deduced nucleotide and amino acid sequences were compared with published sequences for IBV strains. Because of the long-distance similarities, the field samples could be discriminated from vaccine strains. Phylogenetic analysis of RdRp gene sequences resulted in clustering of the IBV strains related to each area. Using RdRp as a genetic marker eliminates the challenges arising from the enormous variations that make it difficult to discriminate between field and vaccine strains as well as affiliate certain variants to various geographical areas.

Correction: Effects of vaccination on acute-phase protein response in broiler chicken.

[This corrects the article DOI: 10.1371/journal.pone.0229009.].

Effects of vaccination on acute-phase protein response in broiler chicken.

Broiler chickens experience an acute-phase response (APR) through vaccination, which reflects the innate immunity and stress related to immunization. It is also considered that APR can modulate adaptive immunity and response to infection. As biomarkers for APR, assessing the acute-phase proteins (APPs) function and their levels in response to immunization is of great value for vaccine design, development and administration. In this study, the heterophils/lymphocyte (H/L) ratio and the level of APPs was evaluated in broilers with three different Newcastle disease (ND) vaccination regimens. Inactivated ND vaccine (IND) was administered by the intramuscular route. Live attenuated strains, Lasota and Vitapest, was administered by ocular routes. H/L ratio, serum amyloid A (SAA) and alpha-1 acid glycoprotein (AGP) were measured before and after two rounds of vaccination on days 10 and 21. In a comparison between the three vaccines, H/L ratio in IND group significantly increased to 3 fold (1.48 ± 0.41) after the first vaccination while the Lasota and Vitapest showed a milder response. The concentration of SAA increased after 24h by 1.8-fold in IND group (0.116 ± 0.015 mg/L) and 2-fold in Lasota group (0.14 ± 0.002 mg/L). Significant changes were found in Vitapest group after 48h post vaccination (0.113 ± 0.016 mg/L). Elevation pattern of AGP, 24 hours after first vaccination in IND (3.5-fold) and Vitapest (2.5-fold) was different from Lasota in which the peak was reached after 48 hours (2.9-fold). Except for IND group, no significant changes in SAA and AGP concentrations were detected after the second vaccination. A significant positive correlation between SAA values at day 22 and HI titers at day 28 (r = 0.998, P≤0. 0.005) was found. According to these results, different types of ND vaccines can cause different patterns of acute phase responses. Assessment of stress and level of acute-phase proteins can be used for prediction of immune response outcomes in vaccine design and development.

Application of high-resolution melting-curve analysis on pvpA gene for detection and classification of Mycoplasma gallisepticum strains.

Mycoplasma gallisepticum (MG) is an avian species pathogen which causes heavy economic losses in the poultry industry. The purpose of this study was to determine genomic diversity of 14 MG field strains from chicken, Chuker partridge and peacock collected during 2009-2012 in Iran by polymerase chain reaction and partial sequencing of the pvpA gene. A High-Resolution Melting (HRM) technique was also developed and applied to differentiate between field and vaccine strains. Sequencing of the pvpA gene revealed a 51 nucleotide deletion, within DR-1 and DR-2, among MG strains from chicken and partridge whilst 63 nucleotides were deleted in MG strain from peacock. One nucleotide substitution was also observed among chicken MG strains. Phylogenetic analysis of the sequences clustered all of the Iranian MG strains into two clades or phylogeny groups; the strains from chicken and partridge in one group (group 1) and the strain from peacock into another group (group 4). HRM analysis has also produced comparable outcome to those of sequencing; four distinct melting curves which correspond to the three MG strains from chicken, Chukar partridge and peacock and ts-11 vaccine strain. Overall, findings of this study point towards a single source of infection for the chicken and partridge MG strains and likelihood of the strains being native and endemic in Iran. Peacock considered as an exotic species in Iran, hence the genetic distance for the pvpA gene. MG can be transmitted easily among different avian species and this distinct peacock strain may pose a threat to poultry industry. Our findings also show that molecular variation among pvpA gene of MG strains could be revealed using the relatively rapid and affordable HRM technique.

Detection and Characterization of Circovirus in Canary Flocks.

Circovirus infections have been documented in adult and nestling canaries (Fringillidae) but the distribution of the virus in the world is not yet known. In captive canary flocks, Circovirus infections have been reported based on the clinical observations. In this study, the presence of both canary circovirus (CaCV) and chicken anemia virus (CAV) in canary flocks was investigated. Virus strains were detected by PCR and direct sequencing of amplified products. Nucleotide sequences were aligned and compared with existing data in GenBank. PCR identified CaCV-positive birds, giving an overall positivity rate of 25%, but all samples were negative for CAV. According to the sequencing data, three distinct strains were identified. Our results indicated a relationship between genetic variation in the replicase gene ( rep) and the geographic regions as well as the feasibility of using the rep gene for virus detection and molecular epidemiology investigations. We are reporting detection and characterization of canary circovirus based on the rep gene. Sequencing results and sequence identity analysis revealed that the rep gene could be used for detecting and discriminating the members of family Circoviridae. This manuscript is the first report of canary circovirus in Iran and of three new strains in the world.

Molecular detection and phylogenetic analysis of Mycoplasma gallisepticum from backyard and commercial turkey flocks in Iran.

Mycoplasma gallisepticum (MG) is economically important pathogen of poultry causes airsacculitis and frequently infraorbital sinusitis in turkeys. Infections may remain without clinical signs, but they can make birds susceptible to secondary infections. This study was carried out for molecular detection and phylogenetic analysis of MG infections in commercial and backyard turkey flocks in some parts of Iran. A total number of 600 swab samples were collected from 18 commercial and 31 backyard turkey flocks. The PCR technique was performed for detecting 16S rRNA gene in the samples. Positive sample were subjected for sequencing of mgc2 gene. The results showed that 48.38% of backyard and 16.66% of commercial farms were positive for MG. These findings suggested the presence of MG in the commercial and backyard turkeys' farms of Iran. The molecular analysis indicated high sequence similarity between some Iranian turkeys isolates with Indian and Pakistanian MG isolates. Furthermore, substitutions of MG nucleic acids and correlated amino acids sequences may lead to some antigenic modifications.