Bovine helper T-cell clones specific for lymphocytes infected with Theileria parva (Muguga)

T-cell clones specific for lymphocytes infected with Theileria parva were derived from animals immunized by infection with T. parva (Muguga). These clones were non-cytolytic and had the BoT4+ BoT8- surface phenotype, BoT4 and BoT8 being the bovine analogues of human CD4 and CD8 molecules. The clones proliferated in response to irradiated autologous lymphoblasts infected with T. parva (Muguga) but not to autologous uninfected lymphoblasts or monocytes. They were parasite strain-specific, in that they did not respond to autologous lymphoblasts infected with another parasite stock, T. parva (Marikebuni). The clones proliferated in the absence of exogenous T-cell growth factor (TCGF) and produced TCGF when stimulated with concanavalin A. Induction of proliferation of the cloned T-cells was genetically restricted, and evidence was obtained which indicated that they were restricted by determinants on class II major histocompatibility complex (MHC) molecules. These findings demonstrate that infections with T. parva stimulate antigen-specific MHC-restricted T-cells with the properties of T-helper cells. The results also provide further evidence for the expression of a parasite strain-specific antigen on the surface of T. parva-infected lymphocytes.     

Monoclonal antibody neutralizes the sporozoite stage of different Theileria parva stocks

Summary Monoclonal antibodies were raised against sporozoites of Theileria parva. One of these antibodies (MAbDi) neutralized the infectivity of sporozoites for lymphocytes in vitro and for cattle in vivo. Neutralization seemed to occur by blocking sporozoite entry into the cell. MAbDi neutralized sporozoites of four unrelated stocks of T. parva , indicating the presence of a common antigenic determinant which may be important in initiating protective immunity.     

新疆温宿县博孜墩乡黄牛同期发情试验效果分析

新疆温宿县博孜墩乡是山区牧业乡,因为交通不便,难以开展人工授精,牛改良程度很低,养牛收益很差。为了加快山区黄牛改良速度,增加牧民收入,我们在该乡牛群比较集中的两个行政村农户家筛选174头母牛进行同期发情后人工授精处理。通过分析同期发情率和受胎率,判断山区牛群同期发情效果。结果表明:这次试验同期发情率为70.68%,受胎率为74.7%。结论:通过现有技术的组装配套,同时加大科普推广和培训力度,可以提高山区黄牛改良速度,提高农牧民饲养管理水平和接受科学能力,从而改善当地传统的改良和饲养管理方式,促进农牧民增收。     

Heterogeneity in the Antibody Response to Foot‐and‐Mouth Disease Primo‐vaccinated Calves

Foot‐and‐mouth disease (FMD) vaccines are routinely used as effective control tools in large regions worldwide and to limit outbreaks during epidemics. Vaccine‐induced protection in cattle has been largely correlated with the FMD virus (FMDV)‐specific antibodies. Genetic control of cattle immune adaptive responses has been demonstrated only for peptide antigens derived from FMDV structural proteins. Here, we quantify the heterogeneity in the antibody response of cattle primo‐vaccinated against FMD and study its association with the genetic background in Holstein and Jersey sires. A total of 377 FMDV‐seronegative calves (122 and 255 calves from 16 and 15 Holstein and Jersey sires, respectively) were included in the study. Samples were taken the day prior to primo‐vaccination and 45 days post‐vaccination (dpv). Animals received commercial tetravalent FMD single emulsion oil vaccines formulated with inactivated FMDV. Total FMDV‐specific antibody responses were studied against three viral strains included in the vaccine, and antibody titres were determined by liquid‐phase blocking ELISA. Three linear hierarchical mixed regression models, one for each strain, were formulated to assess the heterogeneity in the immune responses to vaccination. The dependent variables were the antibody titres induced against each FMDV strain at 45 dpv, whereas sire's ‘breed’ was included as a fixed effect, ‘sire’ was included as a random effect, and ‘farm’ was considered as a hierarchical factor to account for lack of independence of within herd measurements. A significant association was found between anti‐FMDV antibody responses and sire's breed, with lower immune responses found in the Jersey sires’ offspring compared with those from Holstein sires. No significant intrabreed variation was detected. In addition, farm management practices were similar in this study, and results of the serological assays were shown to be repeatable. It therefore seems plausible that differences in the immune response may be expected in the event of a mass vaccination campaigns.     

The Socioeconomic Impacts of Clinically Diagnosed Haemorrhagic Septicaemia on Smallholder Large Ruminant Farmers in Cambodia

Haemorrhagic septicaemia (HS) is an acute fatal infectious disease of mainly cattle and buffalo and outbreaks occur commonly in Cambodia. Disease outbreak reports were examined to select five villages from three provinces for a retrospective investigation of HS epidemiology and socioeconomic impact on smallholders, with an aim of identifying potential benefits from improving disease prevention through biosecurity and vaccination. The Village Animal Health Worker (VAHW) or Chief in each village and 66 affected smallholders were surveyed. At the village level, 24% of all households were affected with an estimated mean village herd morbidity of 10.1% and mortality of 28.8%. Affected farmers reported HS disease morbidity and mortality at 42.7% and 63.6% respectively. Buffalo had a higher morbidity (OR = 2.3; P = 0.003) and mortality (OR = 6.9; P < 0.001) compared with cattle, and unvaccinated large ruminants a higher morbidity (OR = 2.9; P = 0.001). The financial impact varied depending on whether the animal survived, provision of treatment, draught replacement and lost secondary income. The mean cost per affected household was USD 952.50 based on ownership of five large ruminants. The impact per affected animal was USD 375.00, reducing the pre‐disease value by 66.1%. A partial budget revealed an overwhelming incentive for farmers to practice biannual vaccination, with a net benefit of USD 951.58 per household based on an annual disease incidence rate of 1. Sensitivity analysis showed that a net benefit of USD 32.42 remained based on an outbreak every 20 years. This study indicates HS can cause a catastrophic financial shock to smallholders and remains a critical constraint to improving large ruminant productivity and profitability. Addressing HS disease control requires a focus on improving smallholder farmer knowledge of biosecurity and vaccination and should be priority to stakeholders interested in addressing regional food insecurity and poverty reduction.     

Likely Introduction Date of Schmallenberg Virus into France According to Monthly Serological Surveys in Cattle

To estimate the date of introduction of Schmallenberg virus (SBV) into France, the prevalence of antibodies against the virus was determined monthly in cattle from two northern departments from August 2011 to April 2012. Seropositive cattle were detected from October 2011 in both departments with a prevalence of 55.6% in the westernmost department (Meurthe‐et‐Moselle) and of 12.7% in the easternmost department (Manche). Schmallenberg virus seroprevalence then increased rapidly to high levels.     

Detection of Bovine Papilloma Viruses in Wart‐Like Lesions of Upper Gastrointestinal Tract of Cattle and Buffaloes

In present investigation, etiopathological characterization of upper gastrointestinal tract (GIT) tumours of cattle and buffaloes was undertaken. A total of 27 GIT wart‐like lesions in rumen, reticulum, mouth and oesophagus of cattle and buffaloes revealed the presence of small nodular to larger spherical or slender growths with thin base present on mucosa and ruminal pillar. Histopathologically, these cases were diagnosed as fibropapilloma/papilloma. This is the first world record on ruminal papillomatosis in buffaloes. Ruminal warts of cattle and buffaloes revealed the presence of BPV‐5, ‐1 & ‐2, which is the first report of presence of these BPVs in the ruminal warts from India. Quantitative real‐time PCR revealed that DNA samples of different GIT wart‐like lesions contained varying amount of BPV DNA copy numbers. Immunohistochemistry revealed that the PCNA and Ki67 immunopositivity was present in the basal and spinosum layer of the fibropapilloma/papilloma, indicating these as the cellular proliferation site. In conclusion, the present investigation revealed that BPV‐5, ‐1 & ‐2 are associated with certain ruminal wart‐like lesions/growths in cattle and buffaloes, and the basal and spinosum layer of the ruminal fibropapilloma/papilloma were cellular proliferation sites.     

Toll-like receptor 6 gene polymorphisms increase the risk of bovine tuberculosis in Chinese Holstein cattle

Our present study aimed to investigate the effect of four SNPs (G1793A, C1859A, A1980G, G1934A) in toll-like receptor 6 (TLR6) on bovine tuberculosis (bTB) resistance in a case–control study. A total of 603 Chinese Holstein cattle (264 from a dairy farm of Henan province, 339 from Hubei province) were selected to analyze the genotype of TLR6 gene by PCR-RFLP. Genotype frequencies of C1859A and A1980G site differed significantly between bTB-infected and non-infected cows (χ² = 6.062, P = 0.048 and χ² = 6.749, P = 0.034, respectively). Relative risk of tuberculosis incidence result showed that genotypes of AA or CA had greater relative risk (OR = 2.730, 95%CI = 0.869–8.573; OR = 1.547, 95CI% = 0.803–2.982, respectively) than those with genotype CC at C1859A site between bTB-infected and non-infected animals. Genotypes of GG or GA had greater relative risk (OR = 2.986, 95%CI = 1.245–7.165; OR = 1.582, 95%CI = 0.734–3.409, respectively) than those with genotype AA at A1980G site. No significant association can be inferred from G1793A and G1934A polymorphism site. The present study suggests that variants in the TLR6 gene are associated with susceptibility to bTB and the TLR6 gene may be considered as a candidate gene for bTB resistance.     

An immunohistochemical assessment of the cutaneous immune response to louse infestation in cattle

Skin samples were taken from 10 experimental cattle exposed naturally, during a period extending over two winters, to Bovicola bovis and Solenoptes capillatus, five becoming infested and five being protected from infestation by repeated treatment with ectoparasiticides. Skin sections were examined histopathologically and immunohistochemically for expression of the immune cell markers CD3, CD4, CD8 and class II antigens of the major histocompatibility complex (MHC). Louse-infested cattle had a mixed infiltration of the superficial dermis and perifollicular regions with eosinophils and mononuclear cells. The skin of infested cattle differed from that of non-infested cattle in showing significantly more cells expressing CD3, CD4 and MHC class II (P<0.05). Many of the MHC class II(+) cells had dendritic morphology, suggesting active antigen presentation within the lesions. Louse infestations have previously been thought to produce a type 1 hypersensitivity response, mediated by Th2 lymphocytes. However, the increased number of lymphocytes and antigen-presenting cells observed in the present study suggests that in chronic infestation there is activation of local cell-mediated (Th1) immunity.     

Establishment of a sequence-based typing system for BoLA-DQA1 exon 2

In cattle, bovine leukocyte antigens (BoLAs) have been extensively used as markers for bovine diseases and immunological traits. Here, we developed a rapid, high-resolution sequence-based typing (SBT) system for BoLA-DQA1. We amplified 355 bp of BoLA-DQA1 by fully nested polymerase chain reaction (PCR) using the newly constructed primers and then performed direct sequencing of each product. Using this method, we investigated the locus in 51 animals whose BoLA haplotypes had been characterized at the Fifth International BoLA Workshop. We identified 15 distinct DQA1 alleles, and there is no conflict between the typing result of PCR-SBT and restriction fragment length polymorphism analysis. Together with the previously developed method for typing BoLA-DRB3, the PCR-SBT for BoLA-DQA1 clearly provides a useful tool for detailed class IIa haplotype analysis.