Retno Damajanti Soejoedono

Pathotypic characterization of Newcastle disease virus isolated from vaccinated chicken in West Java, Indonesia

Aim: This research was conducted to differentiate and characterize eight Newcastle disease virus (NDV) isolates collected from vaccinated chicken at commercial flocks in West Java, Indonesia, in 2011, 2014 and 2015 by pathotype specific primers. Materials and Methods: A total of eight NDV isolates collected from clinical outbreaks among commercial vaccinated flocks in West Java, Indonesia, in 2011, 2014, and 2015 were used in this study. Reverse transcription-polymerase chain reaction was used to detect and differentiate virulence of NDV strains, using three sets of primers targeting their M and F gene. First primers were universal primers to detect NDV targeting matrix (M) gene. Other two sets of primers were specific for the fusion (F) gene cleavage site sequence of virulent and avirulent NDV strains. Results: Our results showed that three isolates belong to NDV virulent strains, and other five isolates belong to NDV avirulent strains. The nucleotide sequence of the F protein cleavage site showed 112K/R-R-Q/R-K-R/G-F117 on NDV virulent strains and 112G-K/R-Q-G-R-L117 on NDV avirulent strain. Conclusion: Result from the current study suggested that NDV virulent strain were circulating among vaccinated chickens in West Java, Indonesia; this might possess a risk of causing ND outbreaks and causing economic losses within the poultry industry.

Production and characterization of Newcastle disease antibody as a reagent to develop a rapid immunodiagnostic test tool

Aim: This research was conducted to produce and characterize ND antibody as reagent candidate to develop a rapid immunodiagnostic test tool. Materials and Methods: Four New Zealand White rabbits were used in this study and divided into two groups. First group was injected by Sato ND antigen, and second group was injected by genotype VII ND antigen. This study is divided into three steps: (a) ND antibody production, (b) ND antibody purification, and (c) ND antibody characterization. First group was rabbit injected by Sato NDV (5×108.25 egg lethal doses (ELD)50/ml) and second group was injected by genotype VII NDV (5×106.5 ELD50/ml). Antigen induction was performed by subcutaneous administrated for first (day 1) and second (day 14) injection and intravenous administrated for third (day 30) injection. Blood was collected on day 8 after third injection. Results: Antibody production increased on second antigen injection and reached a peak on day 9 after second antigen injection. Sato and genotype VII ND antibody can be produced without adjuvant within 38 days with the highest titer 210. Based on antibody titer data, both antigens induced antibody production in a similar trend. The characterization antibody by SDS-PAGE indicated that molecular weight of immunoglobulin G (IgG) is 154.93 kDa (whole IgG), heavy chain 54.39 kDa, and light chain 27.74 kDa. ND antibodies have specificity to homologous and heterologous NDVs in varying virulence. Conclusion: Sato and genotype VII ND antibodies have been successfully produced within 38 days without adjuvant. Specificity of ND antibodies to NDVs in varying virulence and cross-reaction between Sato ND antibody and genotype VII ND antibody indicates that the characterized ND antibodies can be used as a reagent to develop rapid immunodiagnostic test tools.

Phenotypic and Serotypic Characterization of Staphylococcus aureus Strains from Subclinical Mastitis Cattle (KARAKTERISASI SECARA FENOTIPE DAN SEROTIPE STAPHYLOCOCCUS AUREUS YANG BERASAL DARI MASTITIS SUBKLINIK PADA SAPI)

Staphylococcus aureus is known as a major causative agent of mastitis in dairy cattle. In the presentstudy, 104 isolates of Staphlylococcus originated from subclinical mastitis cattle characterized for thephenotypic properties and the presence of Staphylococcal protein A (Spa). Some bacteria were resistancesagainst several antibiotics were also studied, such as, streptomycin, cefepime, nitrofurantoin, amikacin,chloramphenicol, and ciprofloxacin. About 78% of the isolated were moderately sensitive to nitrofurantoin,while 89% were highly resistant to cefepime and ciprofloxacin. Using the various mammals’ sera, sevenisolates revealed the presence of Spa.