Influence of REV and ALV-J Co-Infection on Immunologic Function of T Lymphocytes and Histopathology in Broiler Chickens

The aim of present investigation is to study the effect of single- and co-infection with REV and ALV-J on T lymphocytes bioactivities and histopathology in broiler chickens. The bioactivities of blood and spleen T lymphocytes including lymphoproliferation responses, cytotoxicitic responses, and histopathology of spleen were detected in broiler chickens singly- or co-infected with REV and ALV-J at different days post inoculation and the virus expressions in spleen of infected broiler chickens were detected with immunofluorescence assay （IFA）. The results indicated that blood and spleen T lymphocytes proliferation responses and cytotoxicity in broilers infected with REV or/and ALV-J were inhibited in the whole observed period compared with controls. In the co-infected chickens they were highly inhibited than in the single-infected. The histopathology of spleen in infected chickens at 17 and 37 d post inoculation （dpi） indicated that cell interium increased, the numbers of lymphocytes decreased, and the regrowth were destroyed or decreased, especially more significantly at 17 than at 37 dpi. The different numbers of virus were detected in spleen lymphocytes in REV- infected and/or ALV-J-infected chickens. In the spleen of co-infected chicken, both REV and ALV-J were detected and the total numbers of viruses were more than in chickens singly-infected with REV or ALV-J. Thus, the co-effect of REV and ALV-J caused more immunosuppression on T lymphocytes bioactivities in broiler chickens than single-effect of ALV-J or REV, which contributed to the sever histopathology and the product of tumor cells. This study will be helpful for understanding the effect of co-infection with many viruses and control them in poultry.     

Maternal Antibody Protected Chicks from Growth Retardation and Immunosuppression Induced by Early Reticuloendotheliosis Virus Infection

To determine if the maternal antibody from breeders vaccinated with cell culture-adapted reticuloendotheliosis virus （REV） could protect chicks from early REV infection, one-day-old chicks with or without anti-REV maternal antibodies were inoculated with REV, and then their growth rates and antibody titers to Newcastle disease virus （NDV） and avian influenza virus （AIV）, after vaccination with inactivated vaccines, were compared. This study indicated that REV infection could cause growth retardation and severely inhibit immune reactions to inactivated vaccines against NDV and Avian influenza virus （AIV, H9 and H5） in one-day-old broilers without maternal antibodies specific to REV. Maternal antibody from breeders vaccinated with an attenuated REV vaccine effectively protected REV-challenged birds from growth retardation and immunosuppression on antibody reactions to NDV and AIV vaccines. Four weeks after vaccination, the HI titers to NDV, AIV-H9, and AIV-H5 in maternal antibody positive and negative groups were 3.36 ＋- 2.04 versus 1.58± 1.69 （P〈0.01）, 6.27±3.87 versus 0.71 ± 1.60 （P〈0.01）, and 6.72±3.92 versus 0.54± 1.44 （P〈0.01）. Maternal antibodies from breeders vaccinated with REV vaccine could successfully protect chicks from REV infection and effectively prevent REV-induced growth retardation and immunosuppression in antibody responses to NDV and AIV.     

Immunological changes of chicken infected with marek‘s disease virus

The experiment was conducted to infect one-day old healthy AA chicks with virulent Marek‘s disease virus(MDV).Compared with the uninfected control chicks,it was undertaken to detect the inductive activity of interlukin-2,expression of IL-2 recepter(IL-2R)and proliferative reaction of T cell in the thymus and spleen;to determine the number of α-naphthyl esterase positive T cells,acid phosphatase positive T cells and antibody forming cells in the thymus,Bursa Fabricius,spleen,cecal tonsil,Harder gand and mucosal lympoid tissue of bronchus;to check the number of T cell in peripheral blood as well as the dynamic changes of the amount of IgG,IgM and IgA in the serum,tear,trachea washings and intestinal secretions of infected chickens at 5,25,45 days old,respectively.The experimental results reveal that immunoregulation of IL-2 in immune organs of infected chicknens was disordered;the cellular and humoral immune functions were significantly depressed in the central and peripheral immune organs;the local or mucosal immune defense function were also markedly decreased in respiratory and digestive tracts.     

The Helper Activities of Different Avian Viruses for Propagation of Recombinant Avian Adeno-Associated Virus

To compare the helper activities of different avian viruses for propagation of recombinant avian adeno-associated virus （rAAAV）, AAV-293 cells were cotransfected with the AAAV vector pAITR-GFP containing green fluorescent protein （GFP） gene, the AAAV helper vector pcDNA-ARC expressing the rep and cap genes, and the adenovirus helper vector pHelper expressing Ad5 E2A, E4, and VA-RNA genes. Chicken embryonic fibroblast （CEF） or chicken embryonic liver （CEL） cells were cotransfected with the AAAV vector and the AAAV helper vector, followed by infection with Marek＇s disease virus （MDV）, avian adenovirus, chicken embryo lethal orphan （CELO） virus or infectious bursal disease virus （IBDV）. Infectious rAAAV particles generated by the two strategies were harvested and titrated on CEF and CEL cells. A significantly higher viral titer was obtained with the helper activity provided by the pHelper vector than by MDV or CELO virus. Further experiments showed that rAAAV-mediated green fluorescent protein （gfp） expression was overtly enhanced by MDV or CELO virus super infection or treatment with sodium butyric acid, but not by IBDV super infection. These data demonstrated that MDV and CELO viruses could provide weak helper activity for propagation of rAAAV, and rAAAV- mediated transgene expression could be enhanced by super infection with the helper viruses.     

Immunological Changes of Chicks Immunized with Marek‘s Disease Vaccines and Challenged with Virulent MD Virus

The experiment was conducted to inoculate one-day old chicks with Marek‘s disecae(MD) trivalent and herpesvirus of turkey(HVT) vaccines separately,and then to challenge them with virulent MD virus(vMDV) at the age of 15 days,and 5,25,45,and 75 days after the challenge with vMDV,comparing with the cotrol-challenged chicks without immunization,to detect the immunoprotetive efficacy and dynamic changes of the inductive activity of interleukin-2(IL-2),expression of IL-2 receptor and proliferative function of T cells in thymus and spleen;the number of ANAET,APT,cells and IgG,IgM,IgA antibody-producing cells in Bursa Fabricius,spleen,thymus,cecal tonsil and Harder gland;as the amount of T cells and IgG,IgA in peripheral blood as well as the content of IgG,IgM and IgA in the tear,trachea washings,bile and intestinal fluids of the experimental chicks.The experimental results firstly demonstrate that the immunoregulation of IL-2,and IL-2 receptor,the cellualr and humoral immune resposes were significantly enhanced in the central and peripheral immune organs;the local mucosal immune funcsignificantly enhanced in the central and peripheral immune organs;the local mucosal immune function were markedly amplified in the respiratory and digestive tracts of the immunized-challenged,chicks,which were closely correlated with the immunoprotection against MD;the immune response and immunoprotective effect of the trivalent vaccine-immunized chicks wrer much better than those of HVT vaccine-immunized chicks.     

Immune Responses of Chicken Immunized with Marek‘s Disease Vaccines

The experiment was conducted to study the dynamic changes of immune responses of chicks immunized with Marck‘s disease(MD) trivalent vaccine and turkey herpesvirus (HVT)at one day age.Results were found that after immunization of chicks with MD vaccines,the interlcukine-2 (IL-2) inductive activity and IL-2 receptor expression of T cells from thymus and spleen significantly increased.suggesting that the immunoregulative function was markedly enhanced in the immune organs;the number of antibody-producing cells,the number and proliferative function of T cells rose markedly in Bursa Fabricius,Splcen and thymus,indicating that the ccllular and humoral immune responses were elevated remarkablly in the central and peripheral immune organs; the number of T and antibody-producing cells as well as the content of IgG,IgA and IgM obviously mounted in cecal tonsil,Harder ian gland mucosal lymphoid tissucs of bronchus along with tears,trachea washings,bilc and intestinal fluids,demonstrating that the local and mucosal immunity was raised in the respiratory and digestive tract;the levels of immune responses mentioned above in the trivalent vaccine-immuniacd chicks were apparently higher than those of HVT-immunized birds.     

Effect of Zinc Toxicity on Lymphoid Organs in Chickens

The experiment was conducted with the objective of studies on effects of zinc toxicity on lymphoid organs by the methods of experimental pathology and flow cytometry (FCM). 200 one-day-old Avian broilers were divided into four groups randomly, and fed on diets as follows: controls (Zn 100mg kg^-1)and zinc toxic (Zn 1 500 mg kg^-1, zinc toxic group Ⅰ; Zn 2000 mg kg^-1, zinc toxic group Ⅱ; Zn 2 500 mg kg^-1, zinc toxic group Ⅲ) for seven weeks. The weight and growth index of the thymus, spleen and bursa of Fabricius were reduced in both zinc toxic group Ⅱ and zinc toxic group Ⅲ when compared with those of control group. The G0/G1 phase of the cell cycles of the lymphoid organs was higher, and S, G2 M phases lower in zinc toxic groups Ⅱ and Ⅲ than in control group. Lymphocytes were depleted and degenerate in the lymphoid organs. The reticular cells of the bursa of Fabricius proliferated and the reticular cells of the thymus were also degenerate and necrotic,particularly in zinc toxic groups Ⅱ and Ⅲ. The results demonstrated that more than 1500 mg kg^-1 impaired the progression of lymphocytes from the G0/G1 phase to S phase obviously, inhibited the development of lymphoid organs and caused marked pathological changes in the lymphoid organs. Potential mechanisms underlying these observations are also discussed.     

Effects of Maternal Dietary Energy Restriction on Fat Deposition of Offspring

The study was carried out to investigate the effects of maternal dietary energy restriction on growth performance, serum indices and fat deposition of offspring. A total of 400 female Arbor Acres （AA） broiler breeders were studied. These female birds involved three experimental treatments and a control group with normal dietary energy diets （ND, 11.7 MJ of ME. kgt during the laying）. In treatments 2, 3 and 4, the energies of diets were 20%, 30% and 50% （LD20, LD30 and LD50） lower than those of the control, respectively. The study commenced at the beginning of the laying period when the total egg production reached 5% of the flock. All the broiler offspring were fed the same diets. The results showed that in low energy diets, offspring showed decreased 1-day-old weight, but 49-day-old weight was higher in LD20 diet （P〈0.05）. For offspring during days 1-49, the average daily gain （ADG） in LD20 group and the feed conversion ratio in LD50 group were improved as compared with those of the control （P〈0.05）. Compared with the control, abdominal fat percentage increased in 49-day-old offspring from LD30 diet （P〈0.05）; the fat content of breast muscle in offspring increased in broilers fed low energy diets （P〈0.05）. In 28-day-old offspring from breeders given LD20 and LD50 diets, liver fat percentages were higher compared with ND （P〈0.05）. The subcutaneous fat thickness in 28-day-old offspring from LD50 group and 49-day-old offspring from LD30 group was higher （P〈0.05）. On day 49, the serum cholesterol （CHO） of offspring from breeders fed LD20 diet and serum high-density lipoprotein （HDL） of offspring from breeders fed LD50 diet reduced compared with those of the control （P〈0.05）. In addition, a higher triiodothyronine （T3） content in serum was found in offspring from broiler breeders given LD20 and LD30 diets （P〈0.05）. Serum thyroxine （T4） in offspring significantly decreased with the decrease of diet energy （P〈0.05）. In conclusion, to a certain extent, dietary energy restriction in breeders could improve growth performance and promote lipid metabolism of offspring.     

Study on Hsp90 Expression in Different Tissues and Its Antibody in Serum of Chickens Infected with Marek’s Diseases

To investigate the dynamic change of heat shock protein 90 （Hsp90） in the genesis and development of tumor, we successfully established tumor animal model using Marek’s disease and then determined the location of Hsp90 in the tumor tissue using immunohistochemistry method, the antibody titer level of Hsp90 in the serum and the expression level in the tissue using enzyme-linked immunosorbent assay （ELISA） method. Our result showed that Hsp90 location in the tumor tissue was signiifcantly associated with the tumor cell and most in the cytoplasm of the tumor cell, and Hsp90 expression level in the tissue and the antibody titer level in the serum was most signiifcantly increased with the development of tumor. This is the ifrst report to show the presence of Hsp90 in tumor tissues induced by the Marek’s disease, with its expression correlated to the tumoral grading. These data may also be valuable for developing new molecular anti-cancer therapies.     

Cloning of Thymidine Kinase Gene of Duck Plague Virus Using Degenerate PCR

The DNA of duck plague virus （DPV） thymidine kinase （TK） gene was cloned and sequenced from a vaccine virus in the study. Degenerate oligonucleotide primers for the consensus site of herpesvirus UL24, TK, and glycoprotein H（gH） gene were used in the polymerase chain reaction （PCR） to amplify DNA product with 3 741-base-pairs （bp） in size. DNA sequence analysis revealed a 1 077-base-pairs （bp） open reading frame （ORF） encoding a 358 amino acid polypeptide homologous to herpesvirus TK proteins. The predicted TK protein shared 31.2, 41.3, 35.7, 37.4, and 28.4% identity with herpes simplex virus typel, equine herpesvirus type 4, Marek＇s disease virus 2, herpesvirus turkey, and infectious laryngotracheitis virus, respectively. Comparison of the amino acid sequences of other herpesvirus TK proteins showed that these proteins were not conserved on the whole, otherwise the portion of the TK proteins corresponding to the nucleotide binding domain and the nucleoside binding site were highly conserved among herpesvirus. Comparison with the amino acid sequences of the conserved nucleotide and nucleoside binding domains of other eleven herpesvirus TK proteins to the predicted DPV peptide confirmed its identity as the DPV TK protein.     

Investigation of Different Characters of Stomata on Three Cocoa Clones with Resistance Level Difference to VSD （Vascular Streak dieback） Disease

The development of the science of cytology and genetics, particularly on cell structure and function provided a breakthrough for breeders and allowed for early selection. Character of stomata density on some commodities was reported as important factor to determine the disease resistance. The research was done for getting information about the differences in the stomata characters influenced on the level of Vascular Streak dieback （VSD） resistance on cocoa. The research was conducted in the Laboratory of Genetics, Gadjah Mada University and leaves samples were conducted in Kendeng Lembu Gardens, PTPN XII. The research used a split plot design with three factors included the type of clones with different levels of VSD disease resistance （PA 191, BL 703 and GS 29）, leaf position （top, middle and base） and leaf age （young and old）. Stomata characters included number of stomata, stomata opening width, stomata wide and stomata diameter were observed. The results showed that the stomata characters in three cacao genotypes with different resistance levels indicated a difference in number of stomata, stomata size, stomata opening width, stomata wide and stomata diameter. Stomata number, stomata opening width and stomata diameter on PA 191 （resistance clone） were lower than the susceptible clones （BL 703 dan GS 29）. The lowest of number and diameter stomata on the base position on the old leaves tissues. Number of stomata, stomata opening width and stomata diameter were estimated role in mechanism of VSD resistance and that were expected could be used as criteria selection to VSD resistance.     

Localization of Inhibin in Some Rat Tissues and Exploration of Its Transport Mechanism

The aims of the study were to determine the distribution of inhibin and its α subunit in some rat tissues by an immunohistochemical method of streptavidin-biotin complex （SABC） and to assess the transport mechanism of inhibin by investigating the localization of inhibin and α subunits in the central nervous system （mainly in hypothalamus and pituitary） of ovariectomized rats. Investigations on the extragonadal tissues of ovariectomized rats showed positive expression of inhibin and its α subunit in heart, kidney, spleen, pancreatic gland cells, but no positive reaction sites were seen in lung, liver, submaxillary gland, and adrenal gland. After injection with inhibin α subunit fragment or inhibin extract, positive reaction sites were observed in hypothalamus and pituitary of ovariectomized rats by SABC. Inhibin and its subunit was present in a wide variety of nonreproductive organs and tissues, and its expression was tissue specific, which indicated that inhibin might play a role in regulating tissue function through autocrine/paracrine mechanisms. Inhibin dimer and α subunit could be transported through the BBB by the method of “separation and reconstruction”.     

Bluetongue Virus （BTV） Serological Survey and Evidence of Emergent BTV-8 Serotype in Morocco

Bluetongue （BT） is an infectious, non-contagious arthropod-borne disease that infects all ruminants, including sheep, cattle, deer, goats and camelids. Bluetongue virus （BTV） belonged to Reoviridae is ARN genome of 19 Kb. Twenty-six BTV serotypes have long been recognized, to be associated with severe disease in certain breeds of sheep, whereas cattle and goats are usually sub-clinically affected. Before 2004, BT was considered an exotic disease in Morocco, however, the first outbreak was observed in 2004 in sheep. This outbreak was caused by the isolated BTV-4. Two years later a BTV-1 emerged in Morocco. Both serotype 1 and serotype 4 circulated after 2007 across the country. The aims of the present work was to perform a serological study on sheep from different regions in Morocco in order to clarify the current BTV epidemiological situation and its evolution from 2009 to 2012, to determine the co-infection rate, and to confirm the possible circulation of other BTV Serotype mainly the BTV-8. All of 436 sera were tested by serum neutralization using reference strains. Results confirm the presence of BTV-4, BTV-1 and BTV-8. However, the present study report for the first time the emerging BTV-8 circulation in Morocco. Moreover, the founding reveal as well a higher co-infection rate in cattle compared to sheep.     

IPM Strategies and Their Dilemmas Including an Introduction to www. eurowheat.org

Information about disease management in winter wheat （Triticum aestiva） in eight European countries was collated and analysed by scientists and extension workers within the European Network for the Durable Exploitation of Crop Protection Strategies （ENDURE）. This included information about specific disease thresholds, decision support systems, host varieties, disease prevalence and pathogen virulence. Major differences in disease prevalence and economic importance were observed. Septoria tritici blotch （Mycosphaerella graminicola） was recognized as the most yield reducing disease in countries with intensive wheat production, but also rust diseases （Puccinia striiformis and Puccinia triticina）, powdery mildew （Blumeria graminis） and Fusarium head blight （Fusarium spp.） were seen as serious disease problems. Examples of current integrated pest management （IPM） strategies in different countries have been reported. Disease management and fungicide use patterns showed major differences, with an average input equivalent to 2.3 full dose rates （TFI） in the UK and a TFI of 0.6 in Denmark. These differences are most likely due to a combination of different cropping systems, climatic differences, disease prevalence, and socio-economic factors. The web based information platform www.eurowheat.org was used for dissemination of information and results including information on control thresholds, cultural practices which can influence disease attack, fungicide efficacy, fungicide resistance, and pathogen virulence, which are all elements supporting 1PM for disease control in wheat. The platform is open to all users. The target groups of EuroWheat information are researchers, advisors, breeders, and similar partners dealing with disease management in wheat.     

An Image-Based Diagnostic Expert System for Corn Diseases

The annual worldwide yield losses due to pests are estimated to be billions of dollars. Integrated pest management （IPM） is one of the most important components of crop production in most agricultural areas of the world, and the effectiveness of crop protection depends on accurate and timely diagnosis of phytosanitary problems. Accurately identifying and treatment depends on the method which used in disease and insect pests diagnosis. Identifying plant diseases is usually difficult and requires a plant pathologist or well-trained technician to accurately describe the case. Moreover, quite a few diseases have similar symptoms making it difficult for non-experts to distinguish disease correctly. Another method of diagnosis depends on comparison of the concerned case with similar ones through one image or more of the symptoms and helps enormously in overcoming difficulties of non-experts. The old adage ＇a picture is worth a thousand words＇ is crucially relevant. Considering the user＇s capability to deal and interact with the expert system easily and clearly, a webbased diagnostic expert-system shell based on production rules （i.e., IF 〈 effects 〉 THEN 〈 causes 〉） and frames with a color image database was developed and applied to corn disease diagnosis as a case study. The expert-system shell was made on a 32-bit multimedia desktop microcomputer. The knowledge base had frames, production rules and synonym words as the result of interview and arrangement. It was desired that 80% of total frames used visual color image data to explain the meaning of observations and conclusions. Visual color image displays with the phrases of questions and answers from the expert system, enables users to identify any disease, makes the right decision, and chooses the right treatment. This may increase their level of understanding of corn disease diagnosis. The expert system can be applied to diagnosis of other plant pests or diseases by easy changes to the knowledge base.     

Study on in vitro Cultural Behaviors of Spermatogonium Stem Cells of New Born Calves

Three methods were adopted in culture spermatogoniums of newly born calf in vitro,such as enzymatic digestion and percoll density gradient centrifugation（MethodⅠ）,tubular fragments culture（MethodⅡ）and tissue culture（MethodⅢ）,and cultural behaviors of cells were observed.The results showed that typical spermatogonium colonies appeard at 144 h of culture by enzymatic digestion-percoll density gradient centrifugation method and tubular fragments culture method,2.5%FBS kept the characteristics of spermatogonium stem cell better than others,produced more mass clones,and FBS of more than 2.5%concentration benefited spermatogonium differentiation and the number of colonies was significantly affected by FBS concentration.After 1 week of culture in method Ⅲ,the diameter of lumens and quantity of sertoli’s cells in tubal wall increased obviously,lumen of seminiferous tubules appeared.Sertoli’s cells kept constant and the number of spermatogoniums decreased obviously after 2 weeks of culture.     

Effect of Metallothionein on Cell Cycle,Apoptosis Rate and Subsets Distribution of Lymphocytes in Peripheral Blood of Dairy Cattle under Heat Stress

[Objective] This study aimed to research the effect of metallothionein on cell cycle, apoptosis rate and subsets distribution of lymphocytes in peripheral blood of dairy cows under heat stress, so as to perfect the regulative mechanism re- searches of MT to anti-heat stress. [Method] Twenty lactating Chinese Holstein cows were randomly divided into four groups （A, B, C and D）, and injected with 0, 4.0, 8.0 and 12.0 mg Zn-metallothionein, respectively by intravenous route. Blood sam- ples were collected at 1＂, 16~, 31~, 46~ and 61~ day, and the dynamic changes of cell cycle, apoptosis rate and subsets distribution of lymphocytes were determined. [Result] The apoptosis rate of cells in group B and C was lower than those in group A by 26.63% （P〉0.05） and 24.84% （P〉0.05） respectively. The number of cells in the Gc/G1 phage in trial groups was increased and the number of cells in the S and GJM phages tended to decrease, but there were no significant differences （P〉 0.05）. The number of CD3~ T cell in three trial groups was greater than those in group A by 7.02% （P〉0.05）, 5.45% （P〉0.05） and 3.85% （P〉0.05） respectively, while the number of CD4~ T cell in trial groups was higher than those in control group by 31.04% （P〈0.05）, 35.68% （P〈0.05） and 39.34% （P〈0.05） respectively. The number of CD8＇ T cell and the levels of CD4＊/CD8~ in trial groups were increased observ- ably, but significant difference （P〈0.05） was observed in the levels of CD4~/CD8~ between groups A and C only. It demonstrated that exogenous Zn-metallothionein can decrease apoptosis rate, improve cell cycle and regulate subsets distribution of lymphocytes in dairy cattle in a dose-dependent manner. [Conclusion] This study will provide scientific basis for safe utilization of MT in dairy industry.     

Effects of Auxins and Media on Callus Induction of Chinese Spring Wheat （Triticum aestivum L.）

The effects of auxins and media on callus induction from the mature and immature embryos of Chinese spring wheat （Triticum aestivum L.） varieties were investigated. It was found that genotype, medium, auxin source and concentration had the significant effects on the induction of embryogenic callus, explants germination and the increment of callus fresh weight. For immature embryos cultured on MS medium, 2 mg L^-1 of 2, 4-D was optimal, and the highest frequency of embryogenic callus （33.50%） was observed. For the mature embryos on N6 medium, 4 mg L^-1 of 2, 4-D was optimal. The frequency of embryogenic callus and increment of callus fresh weight on 2, 4, 5-T media were higher than those on 2, 4-D media, and in the presence of 2, 4, 5-T the precocious germination of explants for all genotypes were significantly suppressed. These results indicated that 2, 4, 5-T was superior to 2, 4-D and NAA in the culture of immature embryos. This is the first report about the effect of 2, 4, 5-T and NAA on wheat tissue culture, particularly in comparison with 2, 4-D in detail.     

Molecular Comparisons of Marek＇s disease virus strains of different pathotypes for their gⅠ, gE, pp38 and meq genes

Five to ten serotype I Marek‘ s disease virus (MDV1) strains of different pathotypes were compared for their DNA sequences of gⅠ, gE, pp38 and meq genes. The reference strains were vMDV GA and JM, vvMDV RB1B and Mdll(pl6), vv MDV strains 648A and 584A, vaccine strain CVI988/Rispens; Chinese strains were: v MDV strain N, vvMDV strain G2, vaccine strain 814. Only random aa changes were found in 12 positions within gE of 497 aa among 10 analyzed strains and in 10 positions within gⅠ of 355 aa among 5 strains. There was no relationship found between virus pathotypes and aa changes of both glycoproteins. The aa changes happened in 14 positions within meq of 339 aa among 5 compared strains. But a proline deletion at aa # 194 in a proline- rich domain of meq were shared by two vaccine strains CVI988/Rispens and 814, the latter was a non - pathogenic vaccine strain of serotype 1 isolated in 1983 in China. In another hand, vv MDV strains 648A demonstrated 5 unique aa changes and 4 of them also located in the proline - rich region. The pp38 was very conservative among sequenced 10 strains, there were only two positions at # 107 and # 109 with an altered in its 290 aa. All tested MDV1 strains had glufamine at # 107, instead, only vaccine CVI988 had arginine at the position and lost its epitope reactive with Mab H19, to which all ether tested MDV1 strains were positive. However, CVI988 and vMDV GA shared a Mab T65 - recognized epitope when there was glyeine at aa # 109. It was glutamie acid at aa # 109 in all other MDV1 strains which were not reactive with Mab T65. It seems like that there is some relationship between pathotypes and sequences of pp38 and meq, but more strains need to be compared.     

miR-34c inhibits proliferation and enhances apoptosis in immature porcine Sertoli cells by targeting the SMAD7 gene

MicroRNAs(miRNAs) are implicated in swine spermatogenesis via their regulations of cell proliferation, apoptosis, and differentiation. Recent studies indicated that miR-34 c is indispensable in the late steps of spermatogenesis. However, whether miR-34 c plays similar important roles in immature porcine Sertoli cells remain unknown. In the present study, we conducted two experiments using a completely randomised design to study the function roles of miR-34 c. The results from experiment I demonstrated that the relative expression level of miR-34 c in swine testicular tissues increased(P=0.0017) quadratically with increasing age, while the relative expression level of SMAD family member 7(SMAD7) decreased(P=0.0009) with curve. Furthermore, miR-34 c expression levels showed a significant negative correlation(P=0.013) with SMAD7 gene expression levels. The results from experiment II indicated that miR-34 c directly targets the SMAD7 gene using a luciferase reporter assay, and suppresses(P0.05) SMAD7 mRNA and protein expressions in immature porcine Sertoli cells. Overexpression of miR-34 c inhibited(P0.05) proliferation and enhanced(P0.05) apoptosis in the immature porcine Sertoli cells, which was supported by the results from the Cell Counting Kit-8(CCK-8) assay, the 5-Ethynyl-2′-deoxyuridine(EdU) assay, and the Annexin V-FITC/PI staining assay. Furthermore, knockdown of SMAD7 via small interfering RNA(siR NA) gave a similar result. It is concluded that miR-34 c inhibits proliferation and enhances apoptosis in immature porcine Sertoli cells by targeting the SMAD7 gene.