Supamit Mekchay

Population structure of four Thai indigenous chicken breeds

BackgroundIn recent years, Thai indigenous chickens have increasingly been bred as an alternative in Thailand poultry market. Due to their popularity, there is a clear need to improve the underlying quality and productivity of these chickens. Studying chicken genetic variation can improve the chicken meat quality as well as conserving rare chicken species. To begin with, a minimal set of molecular markers that can characterize the Thai indigenous chicken breeds is required.ResultsUsing AFLP-PCR, 30 single nucleotide polymorphisms (SNPs) from Thai indigenous chickens were obtained by DNA sequencing. From these SNPs, we genotyped 465 chickens from 7 chicken breeds, comprising four Thai indigenous chicken breeds- Pradhuhangdum (PD), Luenghangkhao (LK), Dang (DA) and Chee (CH), one wild chicken - the red jungle fowls (RJF), and two commercial chicken breeds - the brown egg layer (BL) and commercial broiler (CB). The chicken genotypes reveal unique genetic structures of the four Thai indigenous chicken breeds. The average expected heterozygosities of PD= 0.341, LK= 0.357, DA=0.349 and CH= 0.373, while the references RJF= 0.327, CB=0.324 and BL= 0.285. The FST values among Thai indigenous chicken breeds vary from 0.051 to 0.096. The FST values between the pairs of Thai indigenous chickens and RJF vary from 0.083 to 0.105 and the FST values between the Thai indigenous chickens and the two commercial chicken breeds vary from 0.116 to 0.221. A neighbour-joining tree of all individual chickens showed that the Thai indigenous chickens were clustered into four groups which were closely related to the wild RJF but far from the commercial breeds. Such commercial breeds were split into two closely groups. Using genetic admixture analysis, we observed that the Thai indigenous chicken breeds are likely to share common ancestors with the RJF, while both commercial chicken breeds share the same admixture pattern.ConclusionThese results indicated that the Thai indigenous chicken breeds may descend from the same ancestors. These indigenous chicken breeds were more closely related to red jungle fowls than those of the commercial breeds. These findings showed that the proposed SNP panel can effectively be used to characterize the four Thai indigenous chickens.

Effects of Cordyceps militaris spent mushroom substrate on mucosal and serum immune parameters, disease resistance and growth performance of Nile tilapia, (Oreochromis niloticus)

Abstract The aim of present study was determination effects of dietary administration of C. militaris spent mushroom substrate (SMS) on mucosal and serum immune parameters, disease resistance, and growth performance of Nile tilapia (Oreochromis niloticus). Two hundred twenty five fish of similar weight (37.28 ± 0.10 g) were assigned to the following diets [0 (T1‐ Control), 5 (T2), 10 (T3), 20 (T4) and 40 g kg−1 (T5) SMS]. After 60 days of feeding trial, growth performance, skin mucus lysozyme and peroxidase activities as well as serum innate immune were measured. In addition, survival rate and innate immune responses were calculated after challenge test (15 days) against Streptococcus agalactiae. The results revealed that regardless of inclusion levels, feeding Nile tilapia with SMS supplemented diets significantly increased skin mucus lysozyme and peroxidase activities as well as serum immune parameters (SL, ACH50, PI, RB, and RB) compared control group (P < 0.05). The highest increment of immune parameters was observed in fish fed 10 g kg−1 SMS which was significantly higher than other treatments (P < 0.05). Also, the relative percent survival (RSP) in T2, T3, T4, and T5 was 61.11%, 88.89%, 66.67, and 55.56%, respectively. Among the supplemented groups, fish fed 10 g kg−1 SMS showed significant higher RPS and resistance to S. agalactiae than other groups (P < 0.05). Regarding the growth performance, SGR, WG, FW, and FCR were remarkably improved (P < 0.05) in SMS groups; the highest improvement observed in 10 g kg−1 SMS treatment. According to these finding, administration of 10 g kg−1 SMS is suggested in tilapia to improve growth performance and health status. HighlightsTilapia fed 10 g kg−1 SMS significantly stimulated mucosal and serum immune response.Diet of 10 g kg−1 SMS significantly increased survival rate of O. niloticus against S. agalactiae.Fish fed 10 g kg−1 SMS significantly enhanced growth performance and feed conversion ratio.

In vitro suppression of the MMP-3 gene in normal and cytokine-treated human chondrosarcoma using small interfering RNA

BackgroundMatrix metalloproteinase (MMPs) synthesized and secreted from connective tissue cells have been thought to participate in degradation of the extracellular matrix. Increased MMPs activities that degrade proteoglycans have been measured in osteoarthritis cartilage. This study aims to suppress the expression of the MMP-3 gene in in vitro human chondrosarcoma using siRNA.MethodsCells were categorized into four groups: control (G.1); transfection solution treated (G.2); negative control siRNA treated (G.3); and MMP-3 siRNA treated (G.4). All four groups were further subdivided into two groups - treated and non-treated with IL-1β- following culture for 48 and 72 h. We observed the effects of gene suppression according to cell morphology, glycosaminoglycan (GAG) and hyaluronan (HA) production, and gene expression by using real-time polymerase chain reaction (PCR).ResultsIn IL-1β treated cells the apoptosis rate in G.4 was found to be lower than in all other groups, while viability and mitotic rate were higher than in all other groups (p < 0.05). The production of GAG and HA in G.4 was significantly higher than the control group (p < 0.05). MMP-3 gene expression was downregulated significantly (p < 0.05).ConclusionMMP-3 specific siRNA can inhibit the expression of MMP-3 in chondrosarcoma. This suggests that MMP-3 siRNA has the potential to be a useful preventive and therapeutic agent for osteoarthritis.

Genome-wide identification of allele-specific expression in response to Streptococcus suis 2 infection in two differentially susceptible pig breeds

Although allele expression imbalance has been recognized in many species, and strongly linked to diseases, no whole transcriptome allele imbalance has been detected in pigs during pathogen infections. The pathogen Streptococcus suis 2 (SS2) causes serious zoonotic disease. Different pig breeds show differential susceptibility/resistance to pathogen infection, but the biological insight is little known. Here we analyzed allele-specific expression (ASE) using the spleen transcriptome of four pigs belonging to two phenotypically different breeds after SS2 infection. The comparative analysis of allele specific SNPs between control and infected animals revealed 882 and 1096 statistically significant differentially expressed allele SNPs (criteria: ratio≧2 or ≦0.5) in Landrace and Enshi black pig, respectively. Twenty nine allelically imbalanced SNPs were further verified by Sanger sequencing, and later six SNPs were quantified by pyrosequencing assay. The pyrosequencing results are in agreement with the RNA-seq results, except two SNPs. Looking at the role of ASE in predisposition to diseases, the discovery of causative variants by ASE analysis might help the pig industry in long term to design breeding programs for improving SS2 resistance.

Identification and characterization of novel single nucleotide polymorphism markers for fat deposition in muscle tissue of pigs using amplified fragment length polymorphism

Objective This study was conducted to identify and evaluate the effective single nucleotide polymorphism (SNP) markers for fat deposition in the longissimus dorsi muscles of pigs using the amplified fragment length polymorphism (AFLP) approach. Methods Sixty-four selective primer combinations were used to identify the AFLP markers in the 20 highest- and 20 lowest-intramuscular fat (IMF) content phenotypes. Five AFLP fragments were converted into simple codominant SNP markers. These SNP markers were tested in terms of their association with IMF content and fatty acid (FA) composition traits in 620 commercially crossbred pigs. Results The SSC7 g.4937240C>G marker showed an association with IMF content (p<0.05). The SSC9 g.5496647_5496662insdel marker showed a significant association with IMF content and arachidonic levels (p<0.05). The SSC10 g.71225134G>A marker revealed an association with palmitoleic and ω9 FA levels (p<0.05), while the SSC17 g.61976696G>T marker showed a significant association with IMF content and FA levels of palmitoleic, eicosenoic, arachidonic, monounsaturated fatty acids, and ω9 FA levels. However, no significant association of SSC8 g.47338181G>A was observed with any IMF and FA levels in this study. Conclusion Four SNP markers (SSC7 g.4937240C>G, SSC9 g.5496647_5496662insdel, SSC10 g.71225134G>A, and SSC17 g.61976696G>T) were found to be associated with IMF and/or FA content traits in commercially crossbred pigs. These findings provide evidence of the novel SNP markers as being potentially useful for selecting pigs with the desirable IMF content and FA composition.

Molecular epidemiology and geographical distribution of Nosema ceranae in honeybees, Northern Thailand

Abstract Objective To determine the contamination levels of Nosema ceranae in honeybees and its molecular linkages in different geographical areas of Northern Thailand. Methods Seventy-eight apiaries in Northern Thailand were chosen at random. The detection was accomplished both by microscopic examination and multiplex PCR. Nosema positive samples were evaluated by PCR sequencing and phylogenetic analysis. Results Of the samples subjected to microscopic examination, 11.54% were found to be positive for Nosema while 29.49% of the samples evaluated by PCR were found to be positive for the disease. Honeybees from four of the six provinces surveyed in Northern Thailand were positive for Nosema , with the highest prevalence in Chiang Mai Province (48.57%). There was a high diversity of Nosema strains in some locations, while the same strain of pathogen was identified in many locations in Northern Thailand. Conclusions This is the first report about the contamination levels and distribution pattern of nosemosis in Thailand. The study found the same group of Nosema in different locations, and different groups of Nosema in the same location. This pattern of distribution will be an advantage for disease control in the future.

Association of NR4A1 and GNB2L1 genes with reproductive traits in commercial pig breeds.

The nuclear receptor subfamily 4, group A, member 1 (NR4A1) and guanine nucleotide binding protein beta polypeptide 2 like-1 (GNB2L1) genes are expressed during the ovulatory process and in early pregnancy in pigs. The objective of this study was to analyze the effects of NR4A1 and GNB2L1 gene variants on reproductive traits in commercial pig breeds. Two single nucleotide polymorphisms (SNPs) of NR4A1 and GNB2L1 were identified by a polymerase chain reaction-restriction fragment length polymorphism method. Analysis of the association of these two SNPs with reproductive traits was evaluated in 515 commercial sows (273 Large White and 242 Landrace). The SNP NR4A1 g.3952A>G showed a significant association with the total number of piglets born, the number of piglets born alive, the number of piglets weaned alive, and the litter weight at weaning in the Landrace sows (P < 0.05). A significant association of SNP GNB2L1 g.2373T>C with the litter weight at birth was observed in the Large White sows (P < 0.05). These results indicate that the porcine NR4A1 and GNB2L1 can be used as candidate genes for improvement of litter size traits in pigs.