Electronic Theses and Dissertation

Suhu air merupakan salah satu faktor lingkungan yang sangat menentukan keseimbangan fisiologis dan kelangsungan hidup ikan, karena perubahan suhu dapat memengaruhi metabolisme, respons stres, serta aktivitas biologis lainnya. Ikan Naleh (Barbonymus sp.) sebagai salah satu komoditas perairan tawar memerlukan kisaran suhu yang sesuai agar dapat tumbuh dan bertahan hidup secara optimal. Penelitian ini bertujuan untuk mengetahui pengaruh variasi suhu air terhadap kondisi fisiologis ikan Naleh serta menentukan suhu yang paling optimal bagi kelangsungan hidupnya. Metode penelitian menggunakan rancangan perlakuan suhu berbeda, yaitu P1(20°C), P2(23°C), P3(26°C), P4(29°C) dan P5(32°C). Parameter yang diamati meliputi laju pernapasan, aktivitas, respon makan, tingkat stres, kondisi fisik, kadar glukosa darah, parameter hematologi, serta tingkat kelangsungan hidup ikan. Hasil penelitian menunjukkan bahwa perbedaan suhu air memberikan pengaruh nyata terhadap respons fisiologis ikan Naleh. Perlakuan suhu 29°C menunjukkan kondisi paling baik, yang ditandai dengan laju pernafasan sebesar 42,90 kali/menit, aktivitas sebesar 4,91 dan respon makan sebesar 4,55 yang tinggi, tingkat stress sebesar 4,19 lebih rendah, kondisi fisik stabil sebesar 4,55, kadar glukosa sebesar 84,25 mg/dL yang terkendali, serta kelangsungan hidup sebesar 90% stabil dibandingkan perlakuan suhu 20–23°C maupun 32°C. Selama penelitian berlangsung, kualitas air berada dalam kondisi layak sehingga tidak menjadi faktor pembatas. Berdasarkan hasil tersebut, dapat disimpulkan bahwa suhu 29°C merupakan suhu yang lebih optimal dalam mendukung kondisi fisiologis dan kelangsungan hidup ikan Naleh.

Kata kunci: variasi suhu, fisiologi ikan, ikan Naleh, Barbonymus sp.

Water temperature is one of the environmental factors that strongly determines the physiological balance and survival of fish, because changes in temperature can affect metabolism, stress responses, and other biological activities. Naleh fish (Barbonymus sp.), as one of the freshwater fish commodities, requires an appropriate temperature range in order to grow and survive optimally. This study aimed to determine the effect of water temperature variations on the physiological condition of Naleh fish and to identify the most optimal temperature for their survival. The research method used an experimental design with different temperature treatments, namely P1 (20°C), P2 (23°C), P3 (26°C), P4 (29°C), and P5 (32°C). The observed parameters included respiration rate, activity, feeding response, stress level, physical condition, blood glucose level, hematological parameters, and fish survival rate. The results showed that differences in water temperature had a significant effect on the physiological responses of Naleh fish. The 29°C treatment showed the best condition, indicated by a respiration rate of 42.90 breaths/minute, an activity level of 4.91, and a feeding response of 4.55, which were relatively high, while the stress level was lower at 4.19 . In addition, the physical condition remained stable at 4.55, the blood glucose level was controlled at 84.25 mg/dL, and the survival rate reached 90 %, which was more stable compared to the temperature treatments of 20–23°C and 32°C. During the experiment, water quality remained within an acceptable range and did not become a limiting factor. Based on these results, it can be concluded that 29°C is the most optimal temperature for supporting the physiological condition and survival of Naleh fish. Keywords: temperature variation, fish physiology, Naleh fish, Barbonymus sp.