Tomato farms in Arusha, Morogoro, Dodoma, Iringa, Kilimanjaro and Coast regions of Tanzania were surveyed to assess the incidence of the yellow leaf curl disease, and to collect infected tomato leaf samples for sero-diagnosis. The triple antibody sandwich enzyme linked immunosorbent assay (TAS-ELISA) format was adopted for the detection of disease using commercial polyclonal antiserum and monoclonal antibodies SCRI 17, SCRI 20, SCRI 23 and SCRI 33. ELISA readings were rated on a scale of 0–4. The results of the tests indicated that all the Tomato yellow leaf curl virus (TY-LCV) isolates recorded high reaction values (4) with the polyclonal antibody. However, the Dodoma and Arusha isolates were rated highest in optical density (OD) reading with MAb SCRI 20 and 23. The remaining isolates produced lower OD values. All the isolates rated low (2) when tested with SCRI 33. The differences in reaction to the monoclonal antibodies of TYLCV indicated that variability exists between the coat protein epitopes of TYLCV and Tomato yellow leaf curl Tanzania virus (TYL-CTZV) on one hand, and among the TYLCTZV isolates on the other. Only the isolates from Arusha and Dodoma share a high sequence homology in coat protein with the European and related TYLCV isolates. Furthermore, the reaction with either SCRI 20 or SCRI 23 show that the isolates from Arusha and Dodoma share a high degree of homology, and could belong to one serotype. The other isolates from Morogoro, Coast and Kilimanjaro could form another serotype, while the isolate from Iringa is a different serotype. On the other hand, reaction with SCRI 17 groups the isolates in two serotypes, the Dodoma isolate alone, and another that groups the other five isolates together. It is recommended that other procedures such as DNA-DNA hybridization assays, polymerase chain reaction, restriction fragment length polymorphisms and sequencing can be combined with the use of monoclonal antisera for the detection and prediction or inference of Tomato yellow leaf curl disease (TYLCD) virus relationships at the quasi-species or strain levels in Tanzania.

The number of human cases of salmonellosis in the EU was 94,625 in 2015. Considering the source of these infections, Salmonella spp. was most frequently detected in broiler chicken meat and Salmonella Enteritidis (SE) was the most commonly reported serovar.

The efficacy of probiotics in limiting Salmonella spp. infection in poultry has been demonstrated in numerous papers. The administration of probiotics at the level of primary production reduces the risk of contamination of poultry food products with Salmonella spp.

A study was carried out in order to determine the potential for reducing the Salmonella spp. population in broiler chickens with the use of the Lavipan (JHJ, Poland) probiotic that comprised selected stains of lactic acid bacteria and Saccharomyces cervisae.

Salmonella spp.-free broiler chickens were divided into two groups and received the same feed with (group L) or without (group C) the probiotic throughout the experiment. All day-old chickens were infected per os with SE. Samples of cecum content were collected 2, 4, and 6 weeks after SE infection and pectoral muscles were collected 6 weeks following SE infection for the evaluation of the SE population number. Serum samples for serological examinations were collected 6 weeks after infection.

Six weeks after infection, the number of SE-positive cecal samples was lower in the L group (12.5% positive) in comparison to the C group (87.5%). Similar results were demonstrated for the muscle samples (25% in contrast to 87.5%). At the same time, in both cases, the SE CFU/g was significantly lower in the L group. The results of our study indicate that Lavipan was capable of reducing the population of SE in the gastrointestinal tract, which eventually improved the hygienic parameters of the pectoral muscles.

Four weeks after infection, SE was not detected in any of the experimental groups. In both groups, no specific anti-SE antibodies were detected.

In order to understand infection of avian influenza A virus (AIV) and canine distemper virus (CDV) in the Siberian Tiger in Northeast China, 75 Siberian Tiger serum samples from three cap- tive facilities in northeastern China were collected. AIV and CDV antibody surveillance was test- ed by using hemagglutination inhibition and serum neutralization methods. The results showed that the seroprevalence of H5 AIV, H9 AIV and CDV was respectively 9.33% (7/75), 61.33% (46/75) and 16% (12/75). In the 1<years <2 and > 5 year-old group, the seroprevalence of the H9 AIV was 24% and 80% (P < 0.01), and the CDV seroprevalence was 6% and 36% (P < 0.01), respectively. It was demonstrated that 3 (4%) out of 75 serum samples were AIV+CDV seropos- itive, with 2.67% (2/75) in H9+AIV and 1.33% (1/75) in H5+H9+AIV. To our knowledge, this is the first report of AIV and CDV seroprevalence in Siberian Tigers in China, which will provide base-line data for the control of AIV and CDV infection in Siberian Tigers in China.

Avian encephalomyelitis (AE) is a viral disease of poultry. Although the disease has a milder clinical course in turkeys than in chickens, reproductive flocks of turkeys are vaccinated against AE. Commercial AE ELISA kits are specifically designed for chickens, which makes it difficult to implement these tests in serological monitoring of turkey flocks. The aim of the study was to compare the AE serological results provided by two ELISA kits from different producers when testing an AE-vaccinated flock of turkey hens and their progeny. We detected differences in the sensitivity of the ELISAs for testing specific anti-AE antibody levels in turkey serum samples.

Newcastle disease (ND) is a highly contagious and economically important disease in the poultry industry caused by avian avulavirus-1, historically known as Newcastle disease virus (NDV). Control of ND primarily relies on prophylactic vaccination of flocks, and many vaccines are available on the market, both conventional and more recently introduced new generation recombinant types. To assess the protection level achieved by vaccination ELISA tests are typically used, they also are to track an infection with field strains in non-vaccinated flocks. Special modifications of ELISA can be used as a screening tool to detect infection in flocks vaccinated with new generation vaccines. In this study, we have developed an ELISA test for the detection of antibodies against the nucleoprotein (NP) of NDV and for differentiation of chickens vaccinated with commercial and prototype in-house recombinant vector vaccines from those infected with field NDV strains. The NP gene of LaSota NDV strain expressed in a baculovirus vector was used as a coating antigen in the ELISA. The developed test was optimized, validated and compared to other serological tests. The sensitivity, specificity and accuracy of recombinant NP protein-based ELISA were respectively 96.1%, 96.3%, and 96.2%. Inter-rater (kappa) agreement between the NP-ELISA and the gold standard HI test was calculated to be 0.995. In our comparisons, commercially available ELISA tests revealed different specificities ranging from 95.5–100% and sensitivities at variance, ranging from 90.1 to 99.0%. A high level of maternally derived antibodies was measured in the serum of 1-day-old broilers in the NP-ELISA assay. These antibodies had disappeared and were undetected at 3, 5 and 6 weeks post-vaccination but birds became positive again at 2 weeks after control infection with a velogenic NDV strain. In SPF chickens, antibodies against NP protein were detected only after a challenge. The recombinant NP protein-based ELISA test is sensitive, specific and accurate when compared to the gold standard HI test and commercially available kits. Moreover, the method could be also used for the differentiation between vaccinated and infected birds.

From the naturally infected cucumber plane spherical virus was isolated that mainly on basis of its serological properties has been identified as Tomato black ring virus (TBRV). Using antiserum against TBRV-ED for the specific crapping of virus followed by PCR test (immunocapture-RT-PCR) allowed co distinguish TBRV from related viruses, especially Beet ringspot virus (BRSV). Presence of as many as rwo satellite RNAs should be found as a unique feature of the cucumber isolace.

This work presents some properties of Sunn-hemp mosaic tobamovirus (SHMV) orginally isolated from bean plants. Virus infected host range and induced symptoms that were typical for SHMV Following plant species distinguished SHMV from tobacco mosaic tobamovirus (TMVJ: Phaseolus vulgaris, Pisum sativum, Lupinus albus and Lycopersicon esculentum. In immunobloning the serum against SHMV did not react with TMV and Tomato mosaic tobamovirus (ToMV). The electrophoretical patterns of whole virions and capsid proteins were characteristic for SHMV and different from that of TMV and ToM.