DIAGNOSIS Staphylococcus aureus PENYEBAB MASTITIS SUBKLINIS BERBASIS PROTEIN A DENGAN LATEX AGGLUTINATION MENGGUNAKAN PLASMA DARAH BERBAGAI SPESIES HEWAN

RAHMI FEBRIYANTI, Prof. Dr. drh. Siti Isriana Oktavia Salasia

2015 | Tesis | S2 Sain Veteriner

Staphylococcus aureus merupakan bakteri penyebab utama mastitis subklinis pada sapi perah. Kejadian mastitis subklinis menurunkan kemampuan ternak memproduksi susu baik secara kuantitatif maupun kualitatif. Tingkat kejadian mastitis subklinis dilaporkan sangat tinggi di lapangan. Patogenisitas Staphylococcus aureus pada kejadian mastitis sangat dipengaruhi oleh protein permukaan, terutama adalah protein A. Protein A memiliki peranan penting sebagai faktor antifagositosis dengan mengikat reseptor Fc dari Imunoglobulin G (IgG), sehingga menurunkan sistem imun hospes. Tingginya kejadian kasus mastitis subklinis karena hewan terinfeksi tidak memperlihatkan gejala klinis patognomonik, akibatnya tidak terdiagnosa lebih awal. Kurang memadainya alat diagnosa aplikatif di lapangan juga mempengaruhi ketepatan diagnosa. Tujuan penelitian adalah deteksi mastitis subklinis akibat S.aureus secara langsung dari susu segar berbasis protein A dengan latex agglutination menggunakan plasma berbagai spesies hewan. Penelitian ini menggunakan sebanyak 63 sampel susu segar CMT + yang berasal dari UPT BPPT Dinas Peternakan Kab. Kampar, Riau. Secara garis besar ada tiga tahapan penelitian yang dilakukan paralel. Tahap pertama isolasi dan identifikasi S. aureus menggunakan metode konvensional. Tahap kedua identifikasi molekular dengan Polymerase Chain Reaction (PCR) untuk mendeteksi gen 23S rRNA menggunakan primer spesifik dengan produk 1250 bp. Tahap ketiga dilakukan uji latex agglutination S. aureus pada susu segar dengan menggunakan plasma kelinci, kambing dan kerbau. Hasil identifikasi sebanyak 63 sampel susu segar, diperoleh 30 isolat S. aureus. Staphylococcus aureus memperlihatkan β-hemolisa 63,33%, α-hemolisa 20%, dan non hemolisa 16,67%. Deteksi Protein A menggunakan Serum Soft Agar (SSA) terlihat koloni kompak sebanyak 27 (90%) koloni difus 3 (10%). Hasil uji latex agglutination dengan berbagai plasma menunjukkan bahwa plasma kerbau mampu mendeteksi S. aureus dengan konsentrasi terkecil (103 CFU). Hasil uji latex agglutination memperlihatkan 30 sampel susu segar bereaksi positif yang menunjukkan bahwa dalam susu segar terdapat S. aureus. Hasil uji latex agglutination tersebut sesuai dengan hasil uji konvensional dan molekular dengan produk 1250bp. Dari hasil penelitian ini menunjukkan bahwa uji latex agglutination S. aureus pada susu segar cukup sensitif dan spesifik serta mudah dalam aplikasinya. Kata kunci: Staphylococcus aureus, protein A, plasma darah, latex agglutination

Staphylococcus aureus is the major pathogen causing subclinical mastitis in dairy animals. The cases of subclinical mastitis have impact on the quality and quantity of dairy milk production. Reported subclinical mastitis incidence rate is very high in the field. The pathogenicity of Staphylococcus aureus in subclinical mastitis was mainly enrolled by its surface protein, especially protein A. Protein A has important role as antiphagocytes by binding with Fc receptor on Imunoglobulin G (IgG), to decrease hospes immunity. The number of subclinical mastitis are getting increase due to diagnose problem of pathognomonic disease that infected animals do not show any specific clinical signs. The lack of simple diagnose tool in the field also effected the accuracy of diagnose. This study aimed to detect subclinical mastitis caused by Staphylococcus aureus directly from fresh milk based on protein A with latex agglutination using plasma from various kind of animals. This study used 63 dairy milk samples which showed positive reaction with CMT. The milk samples were acquired from UPT BPPT Livestock Services, Kampar Regency, Riau Province.The research were done in to 3 steps paralelly. The first step were isolation and identification of S. aureus using conventional method. Second steps was molecular identification by Polymerase Chain Reaction (PCR) to detect 23S RNA gene with specific primers with size of 1250 bp. The third step was detection of S. aureus in the dairy milk samples with latex agglutination using rabbit, buffalo, and goat blood plasma. From 63 milk samples, there were 30 isolates could be identified as S. aureus based on the ability to ferment mannitol, positive Gram stain, catalase, coagulase, and VP positive. There were 63,33% of S. aureus showing β-hemolysis, 20% α- hemolysis, and 16,67% of non-hemolysis. The detection of protein A were performed with Serum Soft Agar (SSA), showed 27 (90%) compact colonie and 3 (10%) diffuse colonie. The result of latex agglutination test using various kind of animal blood plasma showed that buffalo’s plasma could detect S. aureus with minimal concentration of the bacteri (103 CFU). The results of latex agglutination test showed 30 milk samples had positive reaction, indicated the existence of S. aureus in that milk. The ability of latex agglutination that by buffalo’s plasma to detect S. aureus revealed the similar results in the convensional as well as molecular identification. It can be concluded that latex agglutination test for S. aureus in fresh milk was quite sensitive and specific, simple and could be used in the field scale. Keywords: Staphylococcus aureus, protein A, Blood Plasma, latex agglutination

Kata Kunci : Staphylococcus aureus, protein A, plasma darah, latex agglutination; Staphylococcus aureus, protein A, Blood Plasma, latex agglutination