Judul: Isolation and Biochemical Characterisation of Long-Tailed Macaque Aerobic Gut Bacteria from Tinjil Island, Indonesia
Abstrak: Monyet ekor panjang (Macaca fascicularis ; MEP) adalah primata bukan manusia yang umum digunakan sebagai hewan model di bidang kesehatan karena kemiripan genetiknya dengan manusia. Menjaga keseimbangan mikrobiota usus MEP sangat penting untuk menghindari kemungkinan penyakit yang disebabkan oleh ketidakseimbangan komposisi mikrobiota usus (dysbiosis). Oleh karena itu, penelitian ini bertujuan untuk mengisolasi dan mengkarakterisasi bakteri usus dari MEP semi-liar dari Pulau Tinjil melalui pendekatan kultivasi bakteri. Empat sampel feses MEP semi-liar diencerkan secara serial dan disebarkan ke media agar untuk penghitungan bakteri hidup kemudian isolat bakteri dikarakterisasi. Rata-rata total bakteri hidup yang diperoleh adalah 1,86 x 109 CFU/g. Isolasi bakteri secara aerobik dari semua sampel ini menghasilkan 19 isolat bakteri Gram positif, enam spesies diduga Staphylococcus spp., empat Micrococcus spp., tiga Bacillus spp., dan enam Corynebacterium spp. Secara umum, isolasi bakteri dari feses MEP semi-liar dari Pulau Tinjil telah memberikan gambaran sederhana bakteri aerob dari usus MEP melalui metode berbasis kultur., Long-tailed macaque (Macaca fascicularis ; LTM) is a common Non-Human Primates (NHPs) used as model organisms in the medical field for its genetic similarity with humans. Maintaining the gut microbiota balance of LTM is crucial to avoid the possibility of disease in LTM caused by dysbiosis. Therefore, this study aims to isolate and characterise gut bacteria from the semi-wild LTM from Tinjil Island through a culture-dependent approach. Four semi-wild LTM faecal samples were serially diluted and spread onto the nutrient agar medium for bacteria enumeration through Total Plate Count (TPC) and then characterised. The average of total viable bacteria obtained was 1.86 x 109 CFU/g. Aerobic isolation of bacteria from all the samples resulted in 19 isolates of Gram-positive bacteria, six putative species of Staphylococcus spp., four Micrococcus spp., three Bacillus spp. and six Corynebacterium spp. The isolation of cultivable faecal bacteria from semi-wild LTM from Tinjil Island has provided a simple overview of LTM aerobic gut bacteria via culture-based methods.
Keyword: Culture-based method, faecal, gut microbiota, Macaca fascicularis, putative-species

Judul: Impact of Dietary Variation on Gut Microbiota  Composition of Macaca fascicularis at the Primate Research Center, IPB  University
Abstrak: Long-tailed macaques (Macaca fascicularis; LTMs), also known as crab eating macaques, are widespread in Southeast Asia and exhibit distinct dietary patterns in captivity and the wild. Captive LTMs, often fed commercial monkey chow and cultivated fruits, are prone to health issues like obesity and diarrhea due to dietary and habitat changes. In contrast, wild LTMs consume a diverse, natural diet that supports a healthier gut microbiome. This research aims to explore the relationship between different diets and gut microbiota profiles of LTMs in two locations: the Dramaga Captive Breeding Facility and Tinjil Island. The study was involving feeding treatment only for LTMs in Dramaga Captive Breeding Facility, then fecal sample collection from LTMs in both the Dramaga Captive Breeding Facility and Tinjil Island. Molecular activities were performed to extract DNA, followed by 16S rRNA gene sequencing and bioinformatic analyses to identify and compare the gut microbiota composition. Captive LTMs exhibited higher gut microbiota diversity than semi-wild LTM. The results showed that Firmicutes, Bacteroidota, and Proteobacteria were dominant in the gut microbial communities of LTMs from both environments, with significant variations at the genera levels. The findings highlight significant differences in gut microbiota between wild and captive LTMs, influenced primarily by their diets. Wild LTM had a higher presence of Proteobacteria, particularly the genus Succinivibrio, associated with the digestion of high-fiber diets typical of their natural food sources. In contrast, captive LTMs, especially LTM in individual cage, exhibited higher Firmicutes/Bacteroidota ratio, which are often linked to carbohydrate-rich diets and potential obesity. Captive LTM in the group cage showed a slightly more balanced gut microbiota, likely due to a more varied diet and greater physical activity. The study emphasizes the need for high-fiber food supplementation in captive LTM diets to maintain gut health and prevent metabolic disorders. The distinct differences in gut microbiota composition between wild and captive LTMs underscore the importance of dietary management in maintaining a healthy gut microbiota balance and overall health in captive LTMs. This research provides valuable insights into the gut microbiota of LTMs in different environments, underscoring the significant impact of diet on their microbial composition and health. The results suggest that more comprehensive dietary strategies should be implemented for captive LTMs to mimic their natural diet as closely as possible. Future research should increase the number of animals studied and integrate comprehensive assessments of LTM behavior, physiological parameters, and microbiota composition for a more holistic understanding of their health dynamics. This approach would offer a broader perspective on how diet and environment shape the gut microbiota and overall health of LTMs, ultimately contributing to improved welfare and management practices for these primates in captivity.
Keyword: 16S rRNA gene sequencing, captive and semi-wild breeding, fecal  samples, natural diets, long-tailed macaques

Judul: Truncated Stop Loss as a Optimal Solution of Reinsurance Agreement in One-Period Model
Abstrak: Reinsurance is one of risk management efforts of an insurance company, which is called the cedent. Similar with insurance, reinsurance constitutes the cedent to pay the premium. We consider one-period reinsurance model and derive a rule which minimizes the ruin probability of the cedent for a fixed reinsurance premium. Therefore, it is needed to construct an optimal reinsurance agreement for the cedent. The premium is calculated according to four different principles, i.e. economic, generalized zero-utility, Esscher, and mean-variance principles. Stop loss is a reinsurance contract which protect the insurance company for losses that exceed a certain amount. The result of this research shows that a truncated stop loss is an optimal agreement in the class of all reinsurance contracts with various premiums calculated using above mentioned principles.
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