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Highlights • RVA vaccination program reduces the frequency and intensity of diarrhea in dairy calves. • The vaccination immune pressure can select specific genotypes in RVA field strains. • RVA genotype G10P[11] in fecal samples of calves from G6P[5] vaccinated dairy cattle herds. Abstract Worldwide, neonatal diarrhea is one of the most important health issues affecting dairy calves, and rotavirus A (RVA) is one of its primary causes. Among the measures to mitigate the risk of diarrhea outbreaks, cow vaccination stands out as one of the most important. However, the immune pressure resulting from routine vaccination may be able to select specific G and P genotypes in RVA field strains. This study aimed to determine the frequency and intensity of neonatal diarrhea and the incidence of RVA and attempted to monitor the G and P genotypes present in the RVA strains circulating in a high milk yield cattle herd vaccinated with RVA G6P[5] strain. Fecal samples (n = 1220) from 122 Holstein heifer calves between 0–30 days old that were born from RVA-vaccinated cows were collected at 10 different time points, regardless of the presence or absence of diarrhea. The presence of RVA in fecal samples was determined by the polyacrylamide gel electrophoresis (PAGE) technique and confirmed by reverse transcription polymerase chain reaction (RT-PCR). G and P amplicons from 10 RVA-positive fecal samples from calves of different ages and collections were subjected to nucleotide sequencing. The proportion of the calves and fecal samples that were positive for RVA were 62.3% (76/122) and 8.1% (99/1220), respectively. Using sequence analysis, all 10 RVA field strains presented genotype G10P[11]. The protection of G6P[5] vaccination is clear, as this genotype was not detected in this study, and it is known that vaccination against RVA reduces the incidence of diarrhea independent of genotype involved. This result demonstrates the importance of epidemiological monitoring of RVA genotypes circulating in vaccinated dairy cattle herds to the early detection of new potential pathogenic RVA strains. [ABSTRACT FROM AUTHOR]

Highlights • P. multocida isolates with high sulfonamide/trimethoprim MICs were detected in 3/29 farms. • These P. multocida isolates were related in their ApaI and SmaI PFGE patterns. • All of them harboured a plasmid of 6050 bp that was closely related to a plasmid of A. pleuropneumoniae. • The plasmid carried intact sul2 and dfrA14 genes, the latter was integrated into a strA gene. Abstract Pasteurella multocida is an important respiratory tract pathogen in intensive livestock farming, especially in pigs. Antimicrobial agents are frequently used to combat infections caused by this pathogen. In a study on antimicrobial resistance among respiratory tract pathogens of pigs from 30 German pig-producing farms, P. multocida isolates (n = 9) with high minimal inhibitory concentration (MIC) values of 16/304 mg/L (n = 2), 32/608 mg/L (n = 3) or ≥64/1216 mg/L (n = 4) for trimethoprim/sulfamethoxazole (1:19) and of ≥512 mg/L (n = 9) for trimethoprim (TMP) were detected in three of these farms. The genetic relatedness of the isolates was investigated via capsule-specific PCR and macrorestriction analyses with Apa I and Sma I. Pulsed-field gel electrophoresis revealed indistinguishable restriction patterns per farm, with slight differences between the three farms. All isolates represented capsular type A. Four representative isolates, that were subjected to whole genome sequencing, shared the multi-locus sequence type (ST) 3. Their plasmids were transformed into E. coli TOP10 with subsequent selection on TMP-containing agar plates. Antimicrobial susceptibility testing and plasmid analysis of the transformants confirmed that they were resistant to sulfonamides and trimethoprim and carried only a single small plasmid. This plasmid was completely sequenced and revealed a size of 6050 bp. Sequence analyses identified the presence of a resistance gene cluster comprising the genes sul2-ΔstrA-dfrA14-ΔstrA-ΔstrB. Further analysis identified a dfrA14 gene cassette being integrated into the strA reading frame. Neither the gene dfrA14 nor this gene cluster have been detected before in P. multocida. [ABSTRACT FROM AUTHOR]

Highlights • Novel variant IBDVs were first identified in China.. • The Chinese novel variant IBDVs were obviously different from the American variant IBDV.. • The serious threat of the variant IBDV to chicken was further confirmed by animal experiments. Abstract Infectious bursal disease (IBD) is one of the most important immunosuppressive diseases that seriously threaten poultry farming and food safety worldwide. The variant strain of infectious bursal disease virus (IBDV) has been greatly neglected for more than 30 years. Recently, the subclinical infection of suspected IBD, causing considerable economic losses, occurred in the main chicken-farming regions of China. Through RT-PCR, sequencing, and phylogenic analyses, novel variant IBDVs were first identified in six provinces of eastern China. Immunological detection further confirmed the antigenic variation of the Chinese variant IBDVs. The Chinese IBDV variants were obviously different from the American IBDV variants, with less than a 97.7% (VP1) or 98.7% (VP2) amino acid sequence identity. Animal experiments further confirmed the serious threat of the variant IBDVs to chickens, demonstrating irreversible damage to the central immune organ, obvious immunosuppression, and growth retardation. This study not only identified the pandemic nature of the novel variant IBDVs for the first time but also discovered the distinct molecular epidemiological characteristics of these viruses, which will contribute more to the control of the disease. [ABSTRACT FROM AUTHOR]

Highlights • Chicken anaemia virus infection influences the course of consecutive infection with LPAI H9N2 and IB viruses. • Higher titres of LPAI-H9N2 or IB viruses have been detected in the oropharyngeal swabs, tracheas and kidneys in CAV previously infected chickens. • Pre-infection with CAV directly correlates with elevated levels of IL-6 (in lung) and IFNγ (in lung and spleen). Abstract Immunosuppressive viral diseases have a great economic importance in the poultry industry due to the increased susceptibility to secondary infections. Chicken anaemia virus (CAV) is one of the major immunosuppressive diseases in chickens. In addition, low pathogenic avian influenza (LPAI) of subtype H9N2 and infectious bronchitis (IB) viruses are among the most frequently reported respiratory viral diseases in poultry worldwide. In the present study, specific pathogen free chickens were used to understand the impact of CAV on secondary infection with LPAI-H9N2 or IB viruses. Clinical outcomes, viral shedding dynamics, and cytokine levels wereassessed. The results exhibit that chickens previously infected with CAV produceconsiderablyhigher titresof LPAI-H9N2 or IB viruses in the oropharyngeal swabs (P < 0.05), tracheas and kidneys. In addition, the immunologic effect of CAV provokedthe development of clinical signs of LPAI-H9N2 and IB virus infections. Moreover, results suggested that pre-infection with CAV directly correlated with elevated levels of IL-6 and IFNγ. These findings underline the importance of CAV pre-infection on LPAI-H9N2 or IB infection in chickens, and indicate that co-circulation of CAV can contribute to the spread and evolution of LPAI H9N2 and IB viruses. [ABSTRACT FROM AUTHOR]

Highlights • The intestine organ transcriptome of kuruma shrimp were constructed. • 63,458 and 44,350 unigenes were obtained from the mock and the WSSV infection sample, respectively. • 12,920 DGEs were identified. • Some immune genes were analyzed. Abstract Intestine is not only the nutrients digestion and absorption centers, but also an important place of microbial infection. Therefore, intestine immunity plays a key defense means for the host against the invasion of pathogenic microorganisms. In this study, we use kuruma shrimp (Marsupenaeus japonicus) as a model to study the intestine immune characteristics of shrimp against WSSV through next-generation sequencing technique. A total of 63,458 and 44,350 unigenes were generated from the control sample and the WSSV infection sample, respectively. Based on homology searches, KEGG, GO, and COG analysis, 39,520 unigenes were annotated. Among them, 12,920 differentially expressed genes were identified. Some of them, including mucin, peritrophin, chitinase, et al., are involved in immune response. These results contribute to a better understanding of the intestine immune response of the shrimp to WSSV. [ABSTRACT FROM AUTHOR]

Highlights • The property of chMDA5(483aa) used as adjuvant was investigated. • ChMDA5(483aa) delivered by adenovirus enhanced chicken humoral and cell-mediated immune response to inactivated NDV vaccine. • ChMDA5(483aa) expressed by adenovirus improved the protective efficacy of inactivated NDV vaccine. • It gained a new method to strengthen the immune efficacy of NDV inactivated vaccine. Abstract Melanoma Differentiation-Associated protein 5 (MDA5) is a cytoplasmic sensor for viral invasion and plays an important role in regulation of the immune response against Newcastle disease virus (NDV) in chickens. MDA5 was used as an adjuvant to enhance the humoral immune response against influenza virus. In the current study, truncated chicken MDA5 [1–483 aa, chMDA5(483aa)] expressed by recombinant adenovirus was administered to specific-pathogen-free (SPF) chickens to improve the immune response induced by inactivated NDV vaccine. A total of 156 SPF chickens were divided into six groups, and after two rounds of immunization, the humoral immune response, cell-mediated immune (CMI) response and the protective efficacy of the vaccines against NDV challenge were evaluated. The results showed that co-administration of chMDA5(483aa) expressed by adenovirus increased the NDV-specific antibody response by 1.7 times and chickens received chMDA5(483aa) also gained a higher level of CMI response. Consistently, the protective efficacy of the inactivated NDV vaccine against virulent NDV (vNDV) challenge was improved by co-administrate with chMDA5(483aa), as indicated by the reduced morbidity and pathological lesions, lower levels of viral load in organs and reduced virus shedding. Our study demonstrated that chMDA5(433aa) expressed by adenovirus could enhance the immune efficacy of inactivated NDV vaccine in chickens and could be a potential adjuvant candidate in developing chicken NDV vaccines. [ABSTRACT FROM AUTHOR]

There is currently limited information on the factors influencing the outcome of rabies vaccination in dogs based on the primary immunization schedule. The objective of this study was to investigate whether selected variables (signalment, number of vaccinations, vaccine brand and multivalence, and time interval between the most recent vaccination and blood sampling) were associated with the achievement of an acceptable titer threshold (based on international standards) and with absolute antibody titers in young dogs vaccinated with commercially available vaccines. Serologic data from 662 dogs tested prior to their first annual booster for rabies were retrospectively reviewed. Neutralizing antibody titers were determined using a fluorescent antibody neutralization test. An acceptable titer threshold (≥0.5 IU/ml) was achieved in 86.5% of the dogs. Dogs that had been vaccinated twice had significantly ( P < 0.001) higher antibody titers compared with dogs vaccinated once. The odds of achieving seropositivity and the median absolute antibody titer tended to decrease with increasing time between vaccination and blood sampling. Dogs vaccinated with monovalent vaccines were more likely to achieve an acceptable titer than dogs vaccinated with polyvalent vaccines. Dogs that were vaccinated after 3–6 months of age were more likely to develop higher antibody titers. These results indicate that the administration of two vaccines rather than one vaccine in the primary immunization schedule for rabies, result in a superior vaccination response and may be a more beneficial policy for ensuring pre-exposure prophylaxis and for travel certification of young dogs. [ABSTRACT FROM AUTHOR]

Ecological, immunological, and epidemiological factors enable bats to transmit an increasingly recognized spectrum of zoonotic agents, and bartonellae are among those emerging pathogens identified in bats and their arthropod ectoparasites. Current data reveal a multifaceted disease ecology where diverse host species distributed around the world interact with a number of Bartonella spp. and several potential vectors. This review summarizes the methods and findings of studies conducted since 2005 to illustrate that Bartonella bacteremia varies by bat species, location, and other potential variables, such as diet with a very high prevalence in hematophagous bats. Among bat families, Bartonella prevalence ranged from 7.3% among Nycteridae to 54.4% in Miniopteridae. Further research can build on these current data to better determine risk factors associated with Bartonella infection in bat populations and the role of their ectoparasites in transmission. [ABSTRACT FROM AUTHOR]

Avian coccidiosis is caused by multiple species of the apicomplexan protozoan, Eimeria , and is one of the most economically devastating enteric diseases for the poultry industry worldwide. Host immunity to Eimeria infection, however, is relatively species-specific. The ability to immunize chickens against different species of Eimeria using a single vaccine will have a major beneficial impact on commercial poultry production. In this paper, we describe the molecular cloning, purification, and vaccination efficacy of a novel Eimeria vaccine candidate, elongation factor-1α (EF-1α). One day-old broiler chickens were given two subcutaneous immunizations one week apart with E. coli -expressed E. tenella recombinant (r)EF-1α protein and evaluated for protection against challenge infection with E. tenella or E. maxima . rEF-1α-vaccinated chickens exhibited increased body weight gains, decreased fecal oocyst output, and greater serum anti-EF-1α antibody levels following challenge infection with either E. tenella or E. maxima compared with unimmunized controls. Vaccination with EF-1α may represent a new approach to inducing cross-protective immunity against avian coccidiosis in the field. [ABSTRACT FROM AUTHOR]

A more thorough understanding of the immunological interactions between Fasciola spp. and their hosts is required if we are to develop new immunotherapies to control fasciolosis. Deeper knowledge of the antigens that are the target of the acquired immune responses of definitive hosts against both Fasciola hepatica and Fasciola gigantica will potentially identify candidate vaccine antigens. Indonesian Thin Tail sheep express a high level of acquired immunity to infection by F. gigantica within 4 weeks of infection and antibodies in Indonesian Thin Tail sera can promote antibody-dependent cell-mediated cytotoxicity against the surface tegument of juvenile F. gigantica in vitro. Given the high protein sequence similarity between F. hepatica and F. gigantica , we hypothesised that antibody from F. gigantica -infected sheep could be used to identify the orthologous proteins in the tegument of F. hepatica . Purified IgG from the sera of F. gigantica -infected Indonesian Thin Tail sheep collected pre-infection and 4 weeks p.i. were incubated with live adult F. hepatica ex vivo and the immunosloughate (immunoprecipitate) formed was isolated and analysed via liquid chromatography-electrospray ionisation-tandem mass spectrometry to identify proteins involved in the immune response. A total of 38 proteins were identified at a significantly higher abundance in the immunosloughate using week 4 IgG, including eight predicted membrane proteins, 20 secreted proteins, nine proteins predicted to be associated with either the lysosomes, the cytoplasm or the cytoskeleton and one protein with an unknown cellular localization. Three of the membrane proteins are transporters including a multidrug resistance protein, an amino acid permease and a glucose transporter. Interestingly, a total of 21 of the 38 proteins matched with proteins recently reported to be associated with the proposed small exosome-like extracellular vesicles of adult F. hepatica , suggesting that the Indonesian Thin Tail week 4 IgG is either recognising individual proteins released from extracellular vesicles or is immunoprecipitating intact exosome-like extracellular vesicles. Five extracellular vesicle membrane proteins were identified including two proteins predicted to be associated with vesicle transport/ exocytosis (VPS4, vacuolar protein sorting-associated protein 4b and the Niemann-Pick C1 protein). RNAseq analysis of the developmental transcription of the 38 immunosloughate proteins showed that the sequences are expressed over a wide abundance range with 21/38 transcripts expressed at a relatively high level from metacercariae to the adult life cycle stage. A notable feature of the immunosloughates was the absence of cytosolic proteins which have been reported to be secreted markers for damage to adult flukes incubated in vitro, suggesting that the proteins observed are not inadvertent contaminants leaking from damaged flukes ex vivo. The identification of tegument protein antigens shared between F. gigantica and F. hepatica is beneficial in terms of the possible development of a dual purpose vaccine effective against both fluke species. [ABSTRACT FROM AUTHOR]

Campylobacteriosis is the most frequently reported zoonotic disease in humans in the EU since 2005. As chicken meat is the main source of contamination, reducing the level of Campylobacter in broiler chicken will lower the risk to consumers. The aim of this project was to evaluate the ability of Lactobacillus salivarius SMXD51 to control Campylobacter jejuni in broilers and to investigate the mechanisms that could be involved. Thirty broilers artificially contaminated with C. jejuni were treated by oral gavage with MRS broth or a bacterial suspension (10 7 CFU) of Lb. salivarius SMXD51 (SMXD51) in MRS broth. At 14 and 35 days of age, Campylobacter and Lb. salivarius loads were assessed in cecal contents. The impact of the treatment on the avian gut microbiota at day 35 was also evaluated. At day 14, the comparison between the control and treated groups showed a significant reduction ( P < 0.05) of 0.82 log. After 35 days, a significant reduction ( P < 0.001) of 2.81 log in Campylobacter loads was observed and 73% of chickens treated with the culture exhibited Campylobacter loads below 7 log 10 CFU/g. Taxonomic analysis revealed that SMXD51 treatment induced significant changes ( P < 0.05) in a limited number of bacterial genera of the avian gut microbiota and partially limited the impact of Campylobacter on Anaerotruncus sp. decrease and Subdoligranulum sp. increase. Thus, SMXD51 exhibits an anti- Campylobacter activity in vivo and can partially prevent the impact of Campylobacter on the avian gut microbiota. [ABSTRACT FROM AUTHOR]

Subfertility in mares is mainly caused by endometrial diseases. Alterations of Toll-like receptors (TLRs) are associated with endometrial disorders in women. This study investigated TLRs 2, 4 and 6 in the equine endometrium. Endometria of 21 mares were examined by histology, PCR and immunohistochemistry. Tissues from 2 mares were considered normal. The remaining showed endometritis, endometrosis and/or angiosclerosis. TLRs 2, 4 and 6 were expressed as transcripts and proteins in all endometria. Immunohistochemistry detected TLRs 2, 4 and 6 in mast cells, luminal and glandular epithelial cells, stromal cells, endothelia, vascular smooth muscle and/or inflammatory cells. Between examined endometria numbers of immunopositive epithelial cells varied considerably; TLRs were located in their cytoplasm and/or the nucleus. All other cell types displayed a cytoplasmic staining. Results indicate a complex and cell-type-specific modulation of TLRs 2, 4 and 6 in the equine endometrium. The lack of a detectable association between a particular disease and a distinct cellular expression may be explained by the often combined presence of several factors with a possible influence on TLRs. This study expands the basic knowledge on equine endometrial immunity and will assist to uncover if immunological alterations contribute to uterine diseases of mares. [ABSTRACT FROM AUTHOR]

A reverse vaccinology system, Vaxign, was used to identify and select a subset of five African Swine Fever (ASF) antigens that were successfully purified from human embryonic kidney 293 (HEK) cells and produced in Modified vaccinia virus Ankara (MVA) viral vectors. Three HEK-purified antigens [B646L (p72), E183L (p54), and O61R (p12)], and three MVA-vectored antigens [B646L, EP153R, and EP402R (CD2v)] were evaluated using a prime-boost immunization regimen swine safety and immunogenicity study. Antibody responses were detected in pigs following prime-boost immunization four weeks apart with the HEK-293-purified p72, p54, and p12 antigens. Notably, sera from the vaccinees were positive by immunofluorescence on ASFV (Georgia 2007/1)-infected primary macrophages. Although MVA-vectored p72, CD2v, and EP153R failed to induce antibody responses, interferon-gamma (IFN-γ + ) spot forming cell responses against all three antigens were detected one week post-boost. The highest IFN-γ + spot forming cell responses were detected against p72 in pigs primed with MVA-p72 and boosted with the recombinant p72. Antigen-specific (p12, p72, CD2v, and EP153R) T-cell proliferative responses were also detected post-boost. Collectively, these results are the first demonstration that ASFV subunit antigens purified from mammalian cells or expressed in MVA vectors are safe and can induce ASFV-specific antibody and T-cell responses following a prime-boost immunization regimen in swine. [ABSTRACT FROM AUTHOR]

The purpose of this study is to investigate the presence of IL-4, IL-8, IL-13 and IFN-γ in equine colostrum and in foals’ serum. Samples were obtained from 14 mares and their healthy foals. Soon after parturition, 10 ml of colostrum was collected, filtered, centrifuged and frozen until assayed. Blood samples were obtained from each foal at birth (TO) and again after 24 h (T24), after which they were frozen until assayed. Serum IgG was measured at 24 h of age with an immunoturbidimetric quantitative method. Cytokine concentration was determined using commercially available ELISA tests. Statistical analyses revealed a significant difference in serum concentration of IL-4 at T0 and at T24 (p < 0.05) and a significant correlation between the serum IL-4 at T24 and colostral IL-4. These results suggest the absorption of IL-4 from colostrum. The presence of IL-8 in the pre-suckle foal’s serum may be due to an endogenous production. With the exception of two samples, there was no IL-13 detected in the foals’ serum at birth and remained undetectable in 8/14 samples after 24 h. This cytokine was also undetectable in four colostrum samples, where its concentration showed a wide range and a high standard deviation. IFN-γ was present in both the colostrum and in the foals serum at birth. [ABSTRACT FROM AUTHOR]

While T cell contribution to IAV immunity is appreciated, data comparing methods to evaluate IFN-γ production by IAV-specific T cells elicited following vaccination is limited. To understand the differential immunogenicity between live-attenuated influenza virus (LAIV) and whole-inactivated virus (WIV) vaccines in relation to induction of peripheral T cell responses, ELISpot and ELISA were used to assess IFN-γ production by peripheral lymphocytes following antigen restimulation. Following restimulation, peripheral blood lymphocytes from WIV-vaccinated pigs had a greater quantity of IFN-γ secreting cells (SC) and IFN-γ secreted compared to LAIV vaccinated and non-vaccinated (NV) pigs. Pig age at time of WIV vaccination significantly impacted peripheral IAV-specific IFN-γ recall response, as did the inclusion of adjuvant in the WIV vaccine. Collectively, these data indicate that peripheral IAV-specific IFN-γ recall responses are not predictive of LAIV vaccination status, thus, are unlikely to be a useful surrogate for evaluating LAIV immunogenicity and predicting cross-protection. However, these data suggest that the evaluation of peripheral IFN-γ recall responses may be useful for identifying factors, such as animal age or vaccine formulation, that may impact parenterally-delivered WIV vaccine immunogenicity. Overall, results did not differ based upon the assay used to evaluate IFN-γ recall responses. Therefore, either ELISpot or ELISA could serve as a measure for evaluating IAV-specific IFN-γ cell-mediated immune responses in swine. [ABSTRACT FROM AUTHOR]

In vitro derivation of dendritic cells (DCs) is an alternative approach to overcome the low frequency of primary DCs and the difficulty of isolation techniques for studying DC immunobiology. To date, the conventional culture protocol of porcine monocyte-derived DCs (MoDCs) has been widely used. However, this protocol is not practical due to the requirement of a substantial number of blood monocytes, and the process often interferes with DC maturation. To improve in vitro porcine MoDC generation, we modified the previous conventional DC generation protocol, based on the human and mouse primary DC culture system, and compared phenotypic and functional features of MoDCs derived from the modified protocol to the conventional protocol. The modified protocol consumed fewer monocytes but generated higher CD1 + cells with DC-like morphology and the ability of maturation. In addition, MoDCs from the modified protocol exhibited increased antigen uptake and IFN-γ production in response to LPS stimulation. Our findings indicate that the modified protocol is expedient and reliable for generating potent MoDCs that substitute for primary DCs. This will be a valuable platform for future research in antigen delivery, vaccines and immunotherapy in pigs, as well as relevant veterinary species. [ABSTRACT FROM AUTHOR]

Heat stress exerts a direct negative effect on farm animal health, triggering physiological responses. Environmental high temperature induces immunosuppression in dairy cows, increasing the risk of mastitis and milk somatic cell counts. The influence of heat stress on leukocytes activities has not been fully elucidated. The present in vitro study was aimed at assessing whether the exposure to temperature simulating conditions of severe whole body hyperthermia affects defensive functions of bovine blood polymorphonuclear cells. Blood was collected from seven clinically healthy, multiparous, late lactating Holstein cows. After isolation, PMN were incubated at either 39 or 41 °C. Phagocytosis, respiratory burst and apoptosis were then investigated. The selected temperatures of 39 °C or 41 °C mimicked conditions of normothermia or severe heat stress, respectively. Phagocytosis assay was carried out by measuring the fluorescence of phagocyted fluorescein-labelled E. coli bioparticles. The modulation of oxidative burst activity was studied by the cytochrome C reduction method. Apoptosis was determined by measuring the activities of two enzymes that play an effector role in the process, namely Caspase-3 and Caspase-7. Statistical analyses were performed using SPSS 22.0. A Student t -test for paired samples and a Generalised Estimating Equation were used based on data distribution. The phagocytosis rate was reduced (−37%, P < 0.01) when PMN were incubated for 2 h at 41 °C, when compared to phagocytosis rate measured at 39 °C. The oxidative burst, as determined by extracellular production of reactive oxygen species (ROS), was also reduced by the exposure of cells to 41 °C compared to 39 °C. Such reduction ranged between −2 and −21% (P < 0.05). Apoptosis rate was not affected by different temperatures. The results reported in this study suggest that phagocytosis and ROS production in PMN exposed to severe high temperature are impaired, partially explaining the higher occurrence of infections during periods of hot weather. [ABSTRACT FROM AUTHOR]

The important role of histamine in chronic gastrointestinal diseases has been increasingly recognized over the last two decades in human medicine. Histamine is released following mast cell activation and exerts its action through binding to four different histamine receptors (H1, H2, H3, and H4). Histamine receptors are dispersed throughout the body, and each different receptor mediates a unique response. Documentation of the presence and type of histamine receptors in the differing sections of the canine gastrointestinal tract will provide additional research opportunities to further explore the role of histamine and its receptors in chronic canine enteropathies, as well as potential therapeutic options. Full thickness gastric, duodenal, jejunal, ileal, and colonic biopsies were obtained from 6 clinically normal adult dogs immediately after humane euthanasia. Commercially available histamine receptor antibodies predicted to react with canine tissues were applied to paraffin-embedded tissue sections using standard immunohistochemistry techniques to identify different histamine receptors. Staining intensity was graded from negative to strong, and the specificity of each antibody was evaluated with western blot. The presence and distribution of histamine receptors varied by anatomic site and histologic level within sections of the canine gastrointestinal tract. All 4 histamine receptors were readily identified, although the distribution of H4 receptors was decreased in comparison to the other histamine receptors. The distribution of the various histamine receptors was similar to that seen in the normal human gastrointestinal tract. H1 receptors were located in the stomach, lymphoid tissue of the ileum and colon, and the smooth muscle and ganglia of all sections. H2 receptors were located in all sections of the gastrointestinal tract, with greatest staining intensity in the gastric mucosa. H3 receptors were located in the stomach and colonic mucosa, smooth muscle and ganglia of all sections, and ileal and colonic lymphoid tissue. H4 receptors were located in the ganglia and smooth muscle of the gastrointestinal tract, as well as the gastric and colonic mucosal and ileal lymphoid tissue. Western blot demonstrated both specific and non-specific staining with the H1 and H3 receptor antibody, but good specificity with the H4 receptor antibody. The H2 receptor antibody was not compatible with western blot techniques, despite excellent immunohistochemical specificity and consistency. Further studies to compare the density and distribution of the various histamine receptors in dogs with gastrointestinal disease are warranted. [ABSTRACT FROM AUTHOR]

The specific factors which regulate differentiation and maturation of dendritic cells in bovine pregnancy remain unclear. We evaluated the influence of physiologically relevant in vitro treatments of progesterone (PG) and estradiol (E2) observed in late pregnancy on the differentiation and maturation of CD14+ monocyte-derived dendritic cell (moDC) from non-pregnant, lactating dairy cows (n = 7). We found that moDC differentiated in the presence of both E2 and PG had impaired E. coli -induced phenotypic maturation, specifically a significant reduction in CD80 and MHC II expression. Contrary to our previous work characterizing moDC from late gestating dairy cattle, we did not observe an increase in CD14 expression relative to the untreated control; this increase was only observed in the current data in the dexamethasone-treated moDC. The moDC treated with a combination of both E2 and PG had significantly greater upregulation of anti-inflammatory cytokine IL-10 relative to the untreated control, but TNFα production was not suppressed; only dexamethasone-treated moDC showed abrogated TNFα production. These data suggest moDC may be regulated by E2 and PG to hinder phenotypic maturation and regulate inflammatory responses. Pregnancy-associated hormone profiles appear to be involved in the generation of maternal immune tolerance in pregnancy. These hormone-facilitated changes to moDC in pregnancy may also impede optimal immune responses to both invading pathogens and routine vaccinations administered in late gestation through limited antigen presentation and increased anti-inflammatory cytokine production. These results provide insight into maternal immune modulation and elucidate potential immune changes necessary to facilitate bovine pregnancy. [ABSTRACT FROM AUTHOR]

Regulatory T cells (Tregs) are known to play an important role in immunoregulation and have been shown to facilitate induction of transplantation tolerance. Chemokine (C-C motif) receptor 4 (CCR4) is expressed on the surface of effector Tregs involved in controlling alloimmune and autoimmune responses. Recently we have developed a novel diphtheria-toxin based anti-human CCR4 immunotoxin for depleting CCR4 + cells in vivo. In this study, we have demonstrated that the anti-human CCR4 immunotoxin bound to porcine lymphocytes including CD4 + FoxP3 + Tregs. Anti-human CCR4 immunotoxin effectively depleted CCR4 + Foxp3 + porcine Tregs in vivo . We observed depletion of up to 70–85% of the CCR4 + Foxp3 + porcine Tregs in the peripheral blood and 85–91% in the lymph nodes following the anti-human CCR4 immunotoxin treatment in Massachusetts General Hospital (MGH) miniature swine. The depletion lasted for about one week with no significant reduction observed within CCR4 − cell populations including CD8α + T cells, CCR4 − CD4 + T cells and B cells. In summary, anti-human CCR4 immunotoxin effectively depleted CCR4 + Foxp3 + porcine Tregs in both peripheral blood and lymph nodes. [ABSTRACT FROM AUTHOR]

CD1 molecules are glycoproteins present primarily on dendritic cells (DCs), which recognize and present a variety of foreign- and self-lipid antigens to T-cells. Humans have five different CD1 isoforms that survey distinct cellular compartments allowing for recognition of a large repertoire of lipids. The canine CD1 family consists of seven functional CD1 molecules (canine CD1a2, CD1a6, CD1a8, CD1a9, CD1b, CD1c and CD1e) and one presumed non-functional isoform (canine CD1d) due to a disrupted gene structure. The aim of this study was to describe in vitro steady-state localization ptterns of canine CD1 isoforms and their correlation with endocytic organelles. GFP-fused canine CD1 293T cell transfectants were stained with markers for early endocytic compartments (EEA-1) and late endocytic/lysosomal compartments (LAMP-1), respectively, and analyzed by confocal microscopy. Canine CD1a molecules localized to the plasma membrane and partially to the early endocytic compartment, but not to late endosomes or lysosomes. In contrast, canine CD1b was highly associated with late endosomal/lysosomal compartments and showed a predominant intracellular expression pattern. Canine CD1c protein expression localized more promiscuously to both the early endosomal compartments and the late endosomal/lysosomal compartments. The canine CD1e molecule showed a strictly intracellular expression with a partial overlap with late endosomal/lysosomal compartments. Lastly, canine CD1d was expressed abnormally showing only a diminished GFP expression. In conclusion, canine CD1 transfectants show distinct localization patterns that are similar to human CD1 proteins with the exception of the canine CD1d isoform, which most likely is non-functional. These findings imply that canine CD1 localization overall resembles human CD1 trafficking patterns. This knowledge is important for the understanding of lipid antigen-receptor immunity in the dog. [ABSTRACT FROM AUTHOR]

Bovine leukemia virus (BLV) is a retrovirus that is widely distributed across US dairy herds: over 83% of herds are BLV-infected and within-herd infection rates can approach 50%. BLV infection reduces both animal longevity and milk production and can interfere with normal immune health. With such a high prevalence of BLV infection in dairy herds, it is essential to understand the circumstances by which BLV negatively affects the immune system of infected cattle. To address this question, BLV- and BLV+ adult, lactating Holstein dairy cows were vaccinated with Bovi-Shield GOLD ® FP ® 5 L5 HB and their immune response to vaccination was measured over the course of 28 days. On day 0 prior to vaccination and days 7, 14 and 28 post-vaccination, fresh PBMCs were characterized for T and B cell ratios in the periphery. Plasma was collected to measure titers of IgM, IgG1 and IgG2 produced against bovine herpesvirus 1 (BHV1), Leptospira hardjo and L. pomona , as well as to characterize neutralizing antibody titers produced against BHV1 and bovine viral diarrhea virus types 1 and 2. On day 18 post-vaccination, PBMCs were cultured in the presence of BHV1 and flow cytometry was used to determine IFNγ production by CD4+, CD8+ and γδ T cells and to investigate CD25 and MHCII expression on B cells. BLV+ cows produced significantly lower titers of IgM against BHV1, L. hardjo and L. pomona and produced lower titers of IgG2 against BHV1. γδ T cells from BLV+ cows displayed a hyper reactive response to stimulation in vitro , although no differences were observed in CD4+ or CD8+ T cell activation. Finally, B cells from BLV+ cows exhibited higher CD25 expression and reduced MHCII expression in response to stimulation in vitro . All together, data from this study support the hypothesis that BLV+ cows fail to respond to vaccination as strongly as BLV- cows and, consequently, may have reduced protective immunity when compared to healthy BLV- cows. [ABSTRACT FROM AUTHOR]

Interleukin 8, also known as CXC chemokine ligand 8 (CXCL8), is a critical chemokine in the recruitment of leukocytes to sites of infection and is a potent mediator of inflammation. We previously discovered 29 polymorphic sites in the promoter region of the bovine Interleukin 8 gene, which segregate into two distinct haplotypes, denoted IL8-h1 and IL8-h2. Population genetic analysis of these two haplotypes showed significant inter-breed differences in haplotype frequency, which is suggestive of selection acting at this locus. Furthermore functional characterisation identified that IL8-h2 was more active in mammary epithelial cells stimulated with the bacterial endotoxin, LPS. However, the in vivo relevance of these functional differences in the IL8 gene has not been ascertained. Therefore, in the current study, we tested the hypothesis that IL8 haplotype would result in variation in the systemic immune response to LPS challenge in Holstein-Friesian (HF) calves. A Taqman assay was designed to genotype both Jersey and HF calves, from which 20 healthy HF calves (representing IL8-h1 and IL8-h2) from the same farm were subjected to LPS stimulation via jugular venepuncture (100 ng/kg). Systemic immune profiling was subsequently performed up to 216 h post-challenge. Haematological analysis showed perturbations in leukocyte populations of cells but only the lymphocyte response was significantly different between IL8-h1 and IL8-h2. IL8 expression levels were significantly different between haplogroups, at both the gene expression and protein levels ( P < 0.05). Circulating neutrophils were subsequently purified from each haplogroup to measure potential haplotype specific effects on neutrophil migration and bacterial killing but no significant differences were detected, which is likely due to the low circulating levels of IL8. We conclude that IL8 haplotype significantly affects IL8 expression profile in response to bacterial endotoxin in vivo , and the significant increase in IL8 in IL8-h2 calves supports our earlier findings in vitro . Genetic variation at the IL8 locus therefore explains a proportion of the inter-breed and inter-individual variation in immunity between neonatal calves which is likely to influence their resistance to infection. [ABSTRACT FROM AUTHOR]

High levels of production in intensive farming systems are associated with increased replacement rates as a result of multifactorial diseases. The so-called “production diseases” may include low-grade infection reducing profitability without increased morbidity. Such infections are sustained by low pathogenic viral and bacterial agents which give rise to full-blown disease in association with poor environmental conditions. In these farms, the results of vaccination may be disappointing. Therefore, fundamental issues should be dealt with toward successful immunoprophylaxis. High lean meat and milk production are associated with chronic inflammation and activation of the innate immune system vis-à-vis cellular stress. This may negatively affect adaptive immune responses. A negative modulation of the host microbiome by farm management practices and drug treatments is a further risk factor. The immune response to stressed cells questions the usual correlates of protection investigated after vaccination. In particular, there is evidence that specific and non-specific immune responses may overlap in vitro as a result of a high level of innate immune responses to Damage-Associated Molecular Patterns (DAMPS) and stress antigens. A vigorous adaptive immune response to microbial agents may be sometimes counterproductive, as suggested in porcine reproductive and respiratory syndrome virus (PRRSV) infection. Alternative outcomes should be sometimes pursued: a better homeostatic control of the inflammatory response, effective and self-limiting innate immune responses, and even tolerance induction. On the whole, successful immunoprophylaxis in intensive farming systems demands co-ordinated and multi-disciplinary efforts in terms of animal breeding, farm management and hygiene, correct choice and harmonization of the prophylactic tools (vaccines, immunomodulators, pre- and probiotics). Finally, there is evidence that disease-predicting parameters of the innate immune response may greatly ease the identification of herds and animals at risk, and contribute to reduced antibiotic usage on farm. [ABSTRACT FROM AUTHOR]

Despite the availability of vaccines and antibiotics, viral, bacterial and parasite-induced intestinal and pulmonary diseases still cause significant losses to the livestock industry. Excepting improvements in calf survival due to predation, there have been only modest improvements in bovine calf survival since 1991. Strikingly, digestive and respiratory diseases still account for almost half of the non-predator deaths in calves. The innate immune system has evolved to rapidly recognize and respond to invasive microbial threats. Augmentation of innate immunity is a broad-spectrum, potent and non-specific alternative approach to effectively counter a microbial invasion. In recent years we have focused our research efforts on the development of effective and inexpensive adjuvant therapies for cattle that can be used to help mitigate infection. Unique in our approach to the development of the potential new treatments, is our focus on bovine γδ T cells, which are important lymphocytes of the innate immune system and of particular importance to ruminant immunological health. This review focuses on recent results obtained using two such adjuvant materials. [ABSTRACT FROM AUTHOR]

Bovine tuberculosis remains a major economic and animal welfare concern worldwide. As part of control strategies, cattle vaccination is being considered. This approach, used alongside conventional control policies, also requires the development of vaccine compatible diagnostic assays to distinguish infected from vaccinated animals (DIVA). In this review we discuss recent advances in DIVA development based on the detection of host cellular immune responses by blood testing or skin testing approaches. [ABSTRACT FROM AUTHOR]

Both rabies virus (RABV) and canine parvovirus (CPV) cause lethal diseases in dogs. In this study, both high egg passage Flury (HEP-Flury) strains of RABV and recombinant RABV carrying double RABV glycoprotein (G) gene were used to express the CPV virion protein 2 (VP2) gene, and were designated rHEP-VP2 and, rHEP-dG-VP2 respectively. The two recombinant RABVs maintained optimal virus titration according to their viral growth kinetics assay compared with the parental strain HEP-Flury. Western blotting indicated that G protein and VP2 were expressed in vitro . The expression of VP2 in Crandell feline kidney cells post-infection by rHEP-VP2 and rHEP-dG-VP2 was confirmed by indirect immunofluorescence assay with antibody against VP2. Immunogenicity of recombinant rabies viruses was tested in Kunming mice. Both rHEP-VP2 and rHEP-dG-VP2 induced high levels of rabies antibody compared with HEP-Flury. Mice immunized with rHEP-VP2 and rHEP-dG-VP2 both had a high level of antibodies against VP2, which can protect against CPV infection. A challenge experiment indicated that more than 80% mice immunized with recombinant RABVs survived after infection of challenge virus standard 24 (CVS-24). Together, this study showed that recombinant RABVs expressing VP2 induced protective immune responses to RABV and CPV. Therefore, rHEP-VP2 and rHEP-dG-VP2 might be potential combined vaccines for RABV and CPV. [ABSTRACT FROM AUTHOR]

The objective of this study was to compare protection provided by type 1 and type 2 porcine reproductive and respiratory syndrome virus (PRRSV) against homologous and heterologous challenge based on clinical, virological, immunological, and pathological analysis. At 3 and 8 weeks of age, pigs were inoculated intranasally with either 3 mL of tissue culture fluid containing 10 5 TCID 50 /mL of type 1 PRRSV or 3 mL of tissue culture fluid containing 10 5 TCID 50 /mL of type 2 PRRSV. The homologous challenges resulted in a significant boost of the neutralizing antibodies (NA) and interferon-γ secreting cells (IFN-γ-SC) compared to heterologous challenges. The reduction of secondary challenging PRRSV viremia coincided with the appearance of homologous PRRSV-specific NA and IFN-γ-SC. Homologous challenge reduced the severity of lung lesions and levels of PRRSV viremia significantly in pigs in comparison with heterologous challenge. The differences in homologous and heterologous NA and IFN-γ-SC response may explain the differences in protection against homologous and heterologous challenge between type 1 and type 2 PRRSV. Primary challenge (immunization) with type 1 PRRSV provided protection against the secondary homologous challenge with type 1 PRRSV but failed to provide protection against the secondary heterologous challenge of type 2 PRRSV. Primary challenge with type 2 PRRSV provided protection against both the secondary homologous challenge with type 2 PRRSV and the secondary heterologous challenge with type 1 PRRSV. [ABSTRACT FROM AUTHOR]

The main objective of this study was to determine the possible effects of thymoquinone (TQ) and curcumin (Cur) on immune-response and pathogenesis of H9N2 avian influenza virus (AIV) in turkeys. The experiment was performed on 75 non-vaccinated mixed-sex turkey poults, divided into 5 experimental groups (A, B, C, D, and E) of 15 birds each. Group A was kept as non-infected and a non-treated negative control (ctrl group) while group B was kept as infected and non-treated positive control (H9N2 group). Turkeys in groups A and B received normal commercial feed while turkeys in groups C and D received TQ, and Cur respectively, and group E concurrently received TQ and Cur from d one through the entire experiment period. All groups were challenged intra-nasally with H9N2 AIV (A/chicken/Pakistan/10RS3039-284-48/2010) at the fourth wk of age except group A. Infected turkeys showed clinical signs of different severity, showing the most prominent disease signs in turkeys in group B. All infected turkeys showed positive results for virus shedding; however, the pattern of virus shedding was different, and with turkeys in group B showing more pronounced virus secretion than the turkeys in the other groups receiving different levels of TQ and Cur. Moreover, significantly higher antibody titer against H9N2 AIV in turkeys shows the immunomodulatory nature of TQ and Cur. Similarly, increased cytokine gene expression suggests antiviral behavior of TQ and Cur especially in combination, leading to suppressed pathogenesis of H9N2 viruses. However, reduced virus shedding and enhanced immune responses were more pronounced in those turkeys receiving TQ and Cur concurrently. This study showed that supplements of TQ and Cur in combination would significantly enhance immune responsiveness and suppress pathogenicity of influenza viruses in turkeys. [ABSTRACT FROM AUTHOR]

Due to an interplay between intestinal microbiota and immune system, disruption of intestinal microbiota composition during immune development may have consequences for immune responses later in life. The present study investigated the effects of antibiotic treatment in the first weeks of life on the specific antibody response later in life in chickens. Layer chicks received an antibiotic cocktail consisting of vancomycin, neomycin, metronidazole, and amphotericin-B by oral gavage every 12 h, and ampicillin and colistin in drinking water for the first week of life. After the first week of life, chicks received ampicillin and colistin in drinking water for two more weeks. Control birds received no antibiotic cocktail and plain drinking water. Fecal microbiota composition was determined during antibiotic treatment (d 8 and 22), two weeks after cessation of antibiotic treatment (d 36), and at the end of the experimental period at d 175 using a 16S ribosomal RNA gene targeted microarray, the Chicken Intestinal Tract Chip (ChickChip). During antibiotic treatment fecal microbiota composition differed strongly between treatment groups. Fecal microbiota of antibiotic treated birds consisted mainly of Proteobacteria, and in particular E.coli, whereas fecal microbiota of control birds consisted mainly of Firmicutes, such as lactobacilli and clostridia. Two weeks after cessation of antibiotic treatment fecal microbiota composition of antibiotic treated birds had recovered and was similar to that of control birds. On d 105, 12 weeks after cessation of antibiotic treatment, chicks of both treatment groups received an intra-tracheal lipopolysaccharide (LPS)/human serum albumin (HuSA) challenge. Antibody titers against LPS and HuSA were measured 10 days after administration of the challenge. While T cell independent antibody titers (LPS) were not affected by antibiotic treatment, antibiotic treated birds showed lower T cell dependent antibody titers (HuSA) compared with control birds. In conclusion, intestinal microbial dysbiosis early in life may still have effects on the specific antibody response months after cessation of antibiotic treatment and despite an apparent recovery in microbiota composition. [ABSTRACT FROM AUTHOR]

Intestinal pathology early in life may affect immune development and therefore immune responses later in life. Dextran sulfate sodium (DSS) induces colitis in rodents and is a widely used model for inflammatory bowel diseases. The present study investigated DSS as a model for early life intestinal pathology and its consequences on intestinal pathology, ileal cytokine, and immunoglobulin mRNA expression levels as well as the antibody response towards an immunological challenge later in life in chickens. Broiler and layer chicks received 2.5% DSS in drinking water during d 11 through d 18 post hatch or plain drinking water as a control. As an immunological challenge all birds received a combination of Escherichia coli lipopolysaccharide (LPS) and human serum albumin (HuSA) intramuscularly (i.m.) at d 35, and antibody titers against LPS, HuSA, and keyhole limpet hemocyanin (KLH) were determined to investigate effects of intestinal inflammation early in life on humoral immunity later in life. DSS treated birds showed a decrease in BW from which broilers quickly recovered, but which persisted for several weeks in layers. Histological examination of intestinal samples showed symptoms similar to those in rodents, including shortening and loss of villi and crypts as well as damage of the epithelial cell layer of different parts of the intestine. Effects of DSS on intestinal morphology were less severe in broilers that also showed a lower mortality in response to DSS than layers. No effect of DSS on ileal cytokine expression levels could be observed, but ileal immunoglobulin expression levels were decreased in DSS treated broilers that also showed lower antibody titers against LPS in response to the challenge. In conclusion, DSS may serve as a model for intestinal pathology early in life, although more research on the appropriate dose is necessary and is likely to differ between breeds. Results from the present study could indicate that broilers are less susceptible to DSS compared with layers or have a better capacity to recover from intestinal pathology. [ABSTRACT FROM AUTHOR]

Ozone therapy has been in use since 1896 in the USA. As a highly reactive molecule, ozone may inactivate bacteria, viruses, fungi, yeasts and protozoans, stimulate the oxygen metabolism of tissue, treat diseases, activate the immune system, and exhibit strong analgesic activity. More recently, ozone has been used in veterinary medicine, particularly in buiatrics, but still insufficiently. Medical ozone therapy has shown effectiveness as an alternative to the use of antibiotics, which are restricted to clinical use and have been withdrawn from non-clinical use as in-feed growth promoters in animal production. This review is an overview of current knowledge regarding the preventive and therapeutic effects of ozone in ruminants for the treatment of puerperal diseases and improvement in their fertility. In particular, ozone preparations have been tested in the treatment of reproductive tract lesions, urovagina and pneumomovagina, metritis, endometritis, fetal membrane retention and mastitis, as well as in the functional restoration of endometrium in dairy cows and goats. In addition, the preventive use of the intrauterine application of ozone has been assessed in order to evaluate its effectiveness in improving reproductive efficiency in dairy cows. No adverse effects were observed in cows and goats treated with ozone preparations. Moreover, there is a lot of evidence indicating the advantages of ozone preparation therapy in comparison to the application of antibiotics. However, there are certain limitations on ozone use in veterinary medicine and buiatrics, such as inactivity against intracellular microbes and selective activity against the same bacterial species, as well as the induction of tissue inflammation through inappropriate application of the preparation. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the effect of Bacillus amyloliquefaciens (BA) on the immune function of broilers challenged with lipopolysaccharide (LPS). 192 one-day-old male Arbor Acre broiler chickens were randomly distributed into four treatments: 1) broilers fed a basal diet; 2) broilers fed a basal diet supplemented with BA; 3) LPS-challenged broilers fed a basal diet; and 4) LPSchallenged broilers fed a basal diet supplemented with BA. Each treatment consisted of six replicates with eight broilers per replicate. Broilers were intraperitoneally injected with either 500 fig LPS per kg body weight or sterile saline at 16, 18 and 20 d of age. LPS decreased the average daily gain (ADG, P = 0.001) and average daily feed intake (P = 0.001). The decreased ADG (P = 0.009) and increased feed conversion ratio (P = 0.047) in LPS-challenged broilers were alleviated by BA. LPS increased the relative spleen weight (P = 0.001). Relative spleen (P = 0.014) and bursa (P = 0.024) weights in the LPS-challenged broilers were reduced by BA. LPS increased white blood cell (WBC) numbers (P = 0.001). However, the WBC numbers (P = 0.042) and the ratio of lymphocytes to WBC (P = 0.020) in LPS-challenged broilers were decreased with BA treatment. LPS decreased plasma lysozyme activity (P = 0.001), but increased concentrations of plasma corticosterone (P = 0.012) and IL-2 (P = 0.020). In contrast, BA increased lysozyme activity in plasma (P = 0.040). LPS increased mRNA abundances of splenic toll-like receptor 4 (P = 0.046), interferon γ (P = 0.008), IL-1β (P = 0.045) and IL-6, (P = 0.006). IL-2 (P = 0.014) and IL-6 (P = 0.074) mRNA abundances in LPSchallenged broilers were reduced by BA, although BA had an opposite effect for IL-10 mRNA expression in those broilers (P = 0.004). In conclusion, BA supplementation could partially alleviate the compromised growth performance and immune status of broilers under immune stress induced by LPS challenge at early age. [ABSTRACT FROM AUTHOR]

Natural antibody (NAb) levels and survival rates were evaluated in 4 breeds of laying hens in Ethiopia: indigenous, improved indigenous, exotic layer, and crossbred. Titers of NAb isotypes IgG and IgM binding keyhole limpet hemocyanin (KLH) in serum were measured at 20, 26, 35, and 45 wk age. Repeatedmeasure ANOVA showed that IgG and IgM levels vary with time within each breed (P < 0.05). Indigenous chickens had significantly (P < 0.05) higher NAb levels at all ages. The Cox proportional hazard analysis showed increased hazard with increased levels of NAbs in the exotic layers (P < 0.05). However, the reduced hazards with increased levels of NAbs were not significant in the improved indigenous and crossbred chickens. Indigenous chickens showed increased hazard with increasing levels of NAb (P > 0.05). We concluded that not only the NAb levels but also the effect of Nabs on survival vary between indigenous and improved breeds. The results indicate that NAb levels are associated with survival in elite (improved) breeds, but are associated with increased hazard in indigenous chickens. [ABSTRACT FROM AUTHOR]

Tasmanian devils ( Sarcophilus harrisii ) risk extinction from a contagious cancer, devil facial tumour disease (DFTD) in which the infectious agent is the tumor cell itself. Because devils are unable to produce an immune response against the tumor cells no devil has survived ‘infection’. To promote an immune response we immunized healthy devils with killed DFTD tumor cells in the presence of adjuvants. Immune responses, including cytotoxicity and antibody production, were detected in five of the six devils. The incorporation of adjuvants that act via toll like receptors may provide additional signals to break ‘immunological ignorance’. One of these devils was protected against a challenge with viable DFTD cells. This was a short-term protection as re-challenge one year later resulted in tumor growth. These results suggest that Tasmanian devils can generate immune responses against DFTD cells. With further optimization of immune stimulation it should be possible to protect Tasmanian devils against DFTD with an injectable vaccine. [ABSTRACT FROM AUTHOR]

Canine leishmaniosis (CanL) caused by the parasite Leishmania infantum is a systemic disease with variable clinical signs. The disease is endemic in the Mediterranean countries and dogs are the main domestic reservoir of the parasite. The quite complicated immune response against the parasite is crucial for the evolution of CanL infection with the skin playing a major role in its immunopathogenesis. After the inoculation of Leishmania promastigotes into the dermis by sand fly bites, complement factors, Langerhan's cells, neutrophils, fibroblasts and keratinocytes are involved in the activation of the innate arm of the skin immune system, with the macrophages and dendritic cells to play a major key role. The effective activation of cellular immunity is the cornerstone of dog's resistance against the parasite. Promastigotes reaching the dermis are engulfed, processed and transferred by APCs to draining lymph nodes to stimulate naïve T-cells for proliferation and differentiation into armed effector T-cells. Th1 cells activate the infected macrophages to kill Leishmania , whereas Th2 cells divert the immune response to humoral immunity and down regulation of cellular immunity with Th1 cell anergy. Inhibition of co-stimulatory molecules expression by infected macrophages contributes to T-cell anergy. In canine subclinical infections cutaneous lymphocytic infiltrate and parasites are absent, as opposed to dogs with clinical leishmaniosis. CD8+ cells constitute a significant population of cellular immunity in CanL since they outnumber CD4+ cells in the dermis, producing IFN-γ in sub clinically infected dogs and high levels of IL-4 in dogs with clinical leishmaniosis. Numerous B-lymphocytes have been shown to heavily infiltrate the dermis at least in exfoliative dermatitis in CanL. A mixed Th1/Th2 cytokine profile has been found in the dermis of naturally infected with L. infantum dogs. In the skin of dogs with clinical leishmaniosis, where plasma cells outnumber T lymphocytes in the dermal infiltrate, there is an overproduction of IL-4, IL-13 and TNF-α leading to Th2-biased humoral immune response. The issue of humoral immunity polarization in CanL remains controversial. Much still needs to be learned about other mechanisms underlying the complex interaction between the skin immune system and the parasite. [ABSTRACT FROM AUTHOR]

Deficiency in immunoglobulin G (IgG) is associated with an increased susceptibility to infections in humans and animals, and changes in IgG levels occur in many disease states. In companion animals, failure of transfer of passive immunity is uncommonly diagnosed but mortality rates in puppies are high and more than 30% of these deaths are secondary to septicemia. Currently, radial immunodiffusion (RID) and enzyme-linked immunosorbent assays are the most commonly used methods for quantitative measurement of IgG in dogs. In this study, a Fourier-transform infrared spectroscopy (FTIR) assay for canine serum IgG was developed and compared to the RID assay as the reference standard. Basic signalment data and health status of the dogs were also analyzed to determine if they correlated with serum IgG concentrations based on RID results. Serum samples were collected from 207 dogs during routine hematological evaluation, and IgG concentrations determined by RID. The FTIR assay was developed using partial least squares regression analysis and its performance evaluated using RID assay as the reference test. The concordance correlation coefficient was 0.91 for the calibration model data set and 0.85 for the prediction set. A Bland–Altman plot showed a mean difference of −89 mg/dL and no systematic bias. The modified mean coefficient of variation (CV) for RID was 6.67%, and for FTIR was 18.76%. The mean serum IgG concentration using RID was 1943 ± 880 mg/dL based on the 193 dogs with complete signalment and health data. When age class, gender, breed size and disease status were analyzed by multivariable ANOVA, dogs <2 years of age ( p = 0.0004) and those classified as diseased ( p = 0.03) were found to have significantly lower IgG concentrations than older and healthy dogs, respectively. [ABSTRACT FROM AUTHOR]

Cytauxzoonosis is a hemoprotozoal disease of cats and wild felids in the South and Southeastern United States caused by Cytauxzoon felis . Although the causative agent has been recognized since the seventies, no study has examined the local immune response in affected organs, such as the lung, and compared them to the lungs of uninfected domestic cats. Previous studies have suggested that the histopathologic findings in the lungs of C. felis -infected cats are caused by the release of pro-inflammatory mediators, such as cytokines and increased production of inducible nitric oxide synthase (iNOS), by the infected macrophages. Our laboratory had previously found an upregulation of the adhesion molecule CD18, which can stimulate the release of these pro-inflammatory mediators. The objective of this study was to characterize local pulmonary immune responses in cats naturally infected with C. felis . Immunohistochemistry was performed to detect tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, iNOS, and major histocompatibility complex (MHC) II in 19 lungs from affected cats that died between 2005 and 2013. Results showed increased expression of all of these molecules when compared to lungs from uninfected, healthy cats. Furthermore, MHC II is expressed in the endothelium of C. felis naturally infected cats. These results support that there is a marked, local, pro-inflammatory immune response that can contribute to the pathogenesis of cytauxzoonosis in the lungs. [ABSTRACT FROM AUTHOR]

Several factors can affect lamb body weight (BW) and immune status during the first days of life, including colostrum source and timing of the first colostrum feeding. The aim of this study was to evaluate the effects of colostrum source (goat or sheep) and timing of the first colostrum feeding (2 or 14 h after birth) on lamb BW and immune status. In this study, 40 lambs were removed from their dams at birth and randomly assigned into 4 groups of 10 lambs each. Lambs were subsequently fed at 2 or 14 h after birth with goat or sheep colostrum. Blood samples and BW recording were performed before feeding. Blood plasma was used to measure the immunoglobulin concentration (IgG and IgM), chitotriosidase activity, and complement system activity (total and alternative pathways). In general, no differences in any of the measured variables were observed among the 4 groups, indicating that neither colostrum source nor timing of the first colostrum feeding had an effect on these variables. These findings may improve management on lamb farms that raise animals under artificial conditions, because our results indicate that it is not necessary to feed colostrum to lambs immediately after birth and that goat colostrum may be used to feed newborn lambs. [ABSTRACT FROM AUTHOR]

Quercetin, among other flavonoids, is under investigation as feed additive for poultry due to its antioxidative properties. Quercetin is also known to possess immunomodulatory and in particular anti-inflammatory properties. As uncompromised immune function is important for poultry productivity and welfare this study investigates possible effects of dietary supplementation of broilers with quercetin on their immune function and immune status. We assessed aspects of the chickens cell-mediated and humoral immune response and immune status when fed with diets supplemented with quercetin at 0.5 and 1 g/kg feed compared to control diets. We measured their cellular immune response to the phytohaemagglutinin skin test, their humoral immune response to sheep red blood cells and assessed the status of the birds’ lymphoid organs and the cell subset composition of the thymus. We found no differences between dietary treatment groups in cellular immune response or immune status (P>0.05). Interestingly, while total and IgM antibody titers did not differ among treatment groups (P>0.05), IgY antibody titers significantly increased with increasing quercetin supplementation (P-linear<0.05). Therefore, dietary quercetin did not compromise any of the immune parameters tested but on the contrary enhanced IgY antibody production. [ABSTRACT FROM AUTHOR]

Abstract: In this study, the effects of Lactobacillus johnsonii XS4 feed supplementation on reproductive performance, gut environment, and blood biochemical and immunological index of sows were investigated. A total of 32 sows (France large white) were allotted into two dietary treatments: Control Group sows received basal diet and Experiment Group received the same diet supplemented with L. johnsonii XS4 (6.0×109 CFU/kg of diet). Treatment started from the day of allocation (90th day of pregnancy) up to the weaning day (25th day of lactation). Homogeneity of the groups was satisfied with regard to parity. From the results it was evident that L. johnsonii XS4 supplementation of the feed improved production performance as shown by the significantly increased litter weight at birth (14.97 vs. 13.08kg, P<0.05), 20 d litter weight (54.9 vs. 49.23kg, P<0.01), the number of piglets at weaning (10.31 vs. 9.43, P<0.05) and weaning litter weight (66.73 vs. 59.18kg, P<0.05). A positive trend was also noticed as regard to the reduction in the back fat thickness during lactation in terms of numerical lesser in the Experimental Group compared with the Control Group (0.79 vs. 1.05mm, P>0.05). The viable count of fecal flora (LAB, E. coli, and S. aureus) revealed no significant differences between the sows of the two groups. Moreover, the supplementation of L. johnsonii XS4 has significant effect on certain blood parameters of sows demonstrating significant increase in serum IgG levels (28.52 vs. 24.87mg/ml, P<0.05) and decrease in alanine aminotransferase concentrations (28.09 vs. 33.92 IU/dl, P<0.01). It is concluded that administration of L. johnsonii XS4 in diets during the end of pregnancy and during lactation had positive effects on the performance of sows. [Copyright &y& Elsevier]

Highlights: [•] Filifoline is an aromatic geranyl derivative obtained by semi-synthesis. [•] Filifolinone is a potential alternative immunomodulator for veterinary use. [•] Filifolinone increases pro-imflammatory and anti- imflammatory cytokynes in SHK-1 cells. [•] In Atlantic salmon, filifolinone upregulates cytokines involved in Th1-type responses. [Copyright &y& Elsevier]

Highlights: [•] Antigen targeting to receptors expressed on APC to improve immune responses in livestock animals. [•] APC subtypes to which antigen should be delivered. [•] Target receptors for antigen delivery. [ABSTRACT FROM AUTHOR]

Abstract: Thymic CD4+CD25+ cells from ducks were characterized for mammalian T regulatory cells’ suppressive and cytokine production properties. The cross reactivity of anti-chicken CD25 monoclonal antibody with duck CD25 was confirmed by evaluating Concanavalin-A-stimulated CD25 upregulation in splenocytes. CD4+CD25+ cells were detectable in the thymus, spleen, cecal tonsil, and lung (airsacs), but not in the bursa. Duck CD4+CD25+ cells had approximately nine-fold higher IL-10 mRNA, 12-fold higher TGF-β, 16-fold higher CTLA-4, and nine-fold higher LAG-3 mRNA amounts than thymic CD4+CD25− cells. Thymic CD4+CD25+ cells had no detectable levels of IL-2 mRNA. Duck CD4+CD25+ cells had a three-fold higher IL-10 mRNA amount than chicken CD4+CD25+ cells. Duck CD4+CD25+ cells were anergic in vitro. Duck CD4+CD25+ cells suppressed naive cell proliferation at effector: responder cell ratios above 0.5:1 in both contact-dependent and -independent pathways. It could be concluded that thymic CD4+CD25+ cells in ducks are most likely the counterpart of mammalian T regulatory cells. [Copyright &y& Elsevier]

Abstract: The 3rd Veterinary Immunology Committee (VIC) Toolkit Workshop took place at the 9th International Veterinary Immunology Symposium (IVIS) in Tokyo, Japan on 18th August 2010. The Workshop built on previous Toolkit Workshops and covered various aspects of reagent development, commercialization and provision to the veterinary immunology research community. The emphasis was on open communication about current progress and future plans to avoid duplication of effort and to update priorities for reagent development. There were presentations on the major reagent development and networking projects such as the BBSRC/RERAD Immunological Toolbox (2004–2009), US Veterinary Immune Reagent Network (VIRN 2006–2010) that has just received renewal funding for 2010–2014, and EU Network for Animal Diseases Infectiology Research Facilities project (NADIR 2009–2013). There were also presentations and discussions on the use of reagents for assay development, particularly multiplexing, and how these new technologies will underpin basic research developments. Mechanisms for improved information exchange, especially though websites with VIC playing a central role, were identified. [Copyright &y& Elsevier]

Abstract: This special issue of Veterinary Immunology and Immunopathology summarizes the Proceedings of the 9th International Veterinary Immunology Symposium (9th IVIS) held August 2010, in Tokyo, Japan. Over 340 delegates from 30 countries discussed research progress analyzing the immune systems of numerous food animals and wildlife, probing basic immunity and the influence of stress, genetics, nutrition, endocrinology and reproduction. Major presentations addressed defense against pathogens and alternative control and prevention strategies including vaccines, adjuvants and novel biotherapeutics. A special Organisation for Economic Co-operation and Development (OECD) Co-operative Research Programme Sponsored Conference on “Vaccination and Diagnosis for Food Safety in Agriculture” highlighted the particular issue of “Immunology in Bovine Paratuberculosis”. In April 2010 there was an outbreak of foot-and-mouth disease (FMD) in the southern part of Japan. This stimulated a special 9th IVIS session on FMD, sponsored by the World Organization for Animal Health (OIE) and the Ministry of Agriculture, Forestry and Fisheries (MAFF) of Japan, to discuss improvements of FMD vaccines, their use in FMD control, and risk assessment for decision management. The 9th IVIS was supported by the Veterinary Immunology Committee (VIC) of the International Union of Immunological Societies (IUIS) and included workshops for its MHC and Toolkit Committees. Finally VIC IUIS presented its 2010 Distinguished Service Award to Dr. Kazuya Yamanouchi for “outstanding contributions to the veterinary immunology community” and its 2010 Distinguished Veterinary Immunologist Award to Dr. Douglas F. Antczak for “outstanding research on equine immunology”. [Copyright &y& Elsevier]

Abstract: The portfolio of reagents for immunology research in veterinary species is limited compared to those available for humans and model biomedical species such as mice. For example, we still lack the reagents to fully ascertain if the immunological paradigms relating to the development, function and inter-relationships between the major T helper cell subsets (Th1, Th2, Th17) apply in ruminants, including goats. Such reagents are essential for rational and strategic approaches to vaccine design based on the identification of correlates of protection. Although a number of human immunological reagents such as monoclonal antibodies (mAb) and cytokines have been shown to cross-react with the farmed ruminant species (cattle, sheep and goats), a greater degree of cross-reactivity is found for reagents specifically developed against ruminant species. Thus, for goats, the most likely sources of cross-reactive reagents are those made against cattle and sheep. Nevertheless, although high inter-species homologies are evident at the gene level in ruminants, cross-reactivity of mAb, cytokines and molecular probes cannot be guaranteed and reagents may have to be developed specifically. Here we review the current availability of immunological reagents for caprine immunology and how those reagents can be used to understand T cell biology. [Copyright &y& Elsevier]

Abstract: Disease caused by gastrointestinal (GI) nematodes is arguably one of the most important health constraints affecting productivity in small ruminants. This is of particular importance for many tropical and subtropical countries where goats play a vital role in the agricultural economies. Anthelmintic resistance is an important component of the losses attributable to parasitoses, unfortunately there is ample evidence that it is more common in goats than in other farmed ruminants. The increased prevalence of anthelmintic resistance in goats can largely be explained by unique aspects of their pharmacology, immunology and behaviour, all of which we need to understand and make allowance for if we are to effectively and sustainably manage anthelmintic resistance in goats. [Copyright &y& Elsevier]

Abstract: The prevalence of feline foamy virus (FFV, spumaretrovirinae) in naturally infected domestic cats ranges between 30 and 80% FFV positive animals depending on age, sex and geographical region analyzed. Two serotypes have been reported for FFV designated FUV7-like and F17/951-like. Serotype-specific neutralization has been shown to correlate with sequence divergence in the surface (SU) domain of the envelope protein (Env). We analyzed a serum collection of 262 domestic cat sera from Germany using a GST-capture ELISA setup screening for Gag and Bet specific antibodies and identified 39% FFV positive animals. Due to the heterogeneity of the serological samples, cut-offs for Gag and Bet reactivity had to be experimentally determined since application of calculated cut-off values yielded some false-positive results; the new cut-off values turned out to be also fully applicable to a previous study. Using the already established FUV7 ElpSU antigen and the newly cloned and produced F17/951 ElpSU antigen, both consisting of the corresponding ectodomains of the envelope leader protein (Elp) and SU protein, we aimed at the detection of Env-specific antibodies and discrimination between the two known FFV serotypes within the diagnostic FFV ELISA. We validated the ElpSU antigens using cat reference sera of known serotype and screened with this assay domestic cat sera from Germany. Use of the FUV7- and F17/951 ElpSU antigens in ELISA resulted in the detection of Env-specific antibodies in both cat reference sera and sera from domestic cats in Germany, but failed to allow serotyping at the same time. [Copyright &y& Elsevier]

Abstract: The innate immune system plays a central role in host defence against viruses. While many studies portray mechanisms in early antiviral immune responses of humans and mice, much remains to be discovered about these mechanisms in the cat. With the objective of shedding light on early host–virus interactions in felids, we have developed 12 real-time TaqMan® qPCR systems for feline genes relevant to innate responses to viral infection, including those encoding for various IFNα and IFNω subtypes, IFNβ, intracellular antiviral factor Mx, NK cell stimulator IL-15 and effectors perforin and granzyme B, as well as Toll-like receptors (TLRs) 3 and 8. Using these newly developed assays and others previously described, we measured the relative expression of selected markers at early time points after viral infection in vitro and in vivo. Feline embryonic fibroblasts (FEA) inoculated with feline leukemia virus (FeLV) indicated peak levels of IFNα, IFNβ and Mx expression already 6h after infection. In contrast, Crandell-Rees feline kidney (CrFK) cells inoculated with feline herpes virus (FHV) responded to infection with high levels of IFNα and IFNβ only after 24h, and no induction of Mx could be detected. In feline PBMCs challenged in vitro with feline immunodeficiency virus (FIV), maximal expression levels of IFNα, β and ω subtype genes as well as IL-15 and TLRs 3, 7 and 8 were measured between 12 and 24h after infection, whereas expression levels of proinflammatory cytokine gene IL-6 were consistently downregulated until 48h post inoculation. A marginal upregulation of granzyme B was also observed within 3h after infection. In an in vivo experiment, cats challenged with FIV exhibited a 2.4-fold increase in IFNα expression in blood 1 week post infection. We furthermore demonstrate the possibility of stimulating feline immune cells in vitro with various immune response modifiers (IRMs) already known for their immunostimulatory properties in mice and humans, namely Poly IC, Resiquimod (R-848) and dSLIM™, a synthetic oligonucleotide containing several unmethylated CpG motifs. Stimulation of feline PBMCs with dSLIM™ and R-848 effectively enhanced expression of IFNα within 12h by factors of 6 and 12, respectively, and Poly IC induced an increase in Mx mRNA expression of 28-fold. Altogether, we describe new molecular tools and their successful use for the characterization of innate immune responses against viruses in the cat and provide evidence that feline cells can be stimulated by synthetic molecules to enhance their antiviral defence mechanisms. [Copyright &y& Elsevier]