Growth Response of Bileh Fish Juveniles (Rasbora sp.) Reared at Different Temperatures

Irhami S, Agusriati Muliyana, Fitria Rahmayanti, Muktaridha Muktaridha — Thu, 30 Apr 2026 00:00:00 +0700

Bileh fish (Rasbora s.) is a freshwater species with high economic value and strong potential to be developed as an aquaculture commodity through domestication efforts to reduce exploitation pressure on wild populations. One of the key environmental factors influencing the success of domestication is rearing temperature, as it directly affects physiological processes and metabolic activity in fish. This study aimed to evaluate the growth response of bileh fish juveniles reared at different temperatures under controlled aquaculture conditions. The experiment was conducted at the Hatchery of the Faculty of Fisheries and Marine Sciences, Teuku Umar University, from July to August 2025 for a period of 40 days. A Completely Randomized Design was applied with four temperature treatments, namely 20°C (P1), 24°C (P2), 28°C (P3), and 32°C (P4), each with three replications. The observed parameters included absolute weight gain, absolute length gain, relative growth rate, and water quality parameters (temperature and pH). The results demonstrated that rearing temperature had a significant effect (P<0.05) on the growth performance of bileh fish juveniles. Optimal growth was achieved at 24°C (P2), with an absolute weight gain of 0.45 g, an absolute length gain of 2.1 cm, and a relative growth rate of 1.13%. In contrast, the 32°C treatment resulted in the lowest growth performance and greater pH variability (6–8). Temperature plays a critical role in fish metabolism, where excessively high temperatures increase energy demands for maintaining homeostasis, thereby limiting energy allocation for growth. Therefore, a rearing temperature of 24°C is recommended as the optimal condition for the culture of bileh fish juveniles.

Determinants of Embryo Transfer Success in Tropical Dairy Cattle: Integrating Reproductive Performance and Institutional Factors

Mohamad Nurul, Abd. Rohman, Suherman — Fri, 10 Apr 2026 00:00:00 +0700

Embryo transfer (ET) is an advanced reproductive biotechnology widely promoted to accelerate genetic improvement and productivity of dairy cattle. However, the success of ET programs in tropical smallholder systems remains inconsistent due to the interaction of biological, environmental, and institutional factors. This study aimed to identify the determinants of ET success by integrating reproductive performance analysis with institutional implementation assessment in tropical dairy production systems. A mixed-methods approach was used, combining quantitative analysis of 200 recipient dairy cows with qualitative interviews involving farmers, technicians, and livestock officials in Pasuruan Regency, East Java, Indonesia. Binary logistic regression was employed to evaluate the influence of embryo characteristics, recipient conditions, environmental stress, disease history, and technician experience on pregnancy outcomes. The results showed that pregnancy rates ranged between 20 and 50%, with fresh embryos achieving higher success than frozen embryos. Logistic regression analysis indicated that technician experience significantly increased the probability of pregnancy (OR = 1.236; p < 0.05), highlighting the critical role of technical capacity in ET implementation. Other factors, such as embryo quality, body condition score, parity, and heat stress, showed variable but statistically nonsignificant effects. Qualitative findings further revealed that limited technical human resources, inconsistent monitoring systems, and weak institutional coordination constrained program effectiveness. These findings demonstrate that ET success in tropical dairy systems is shaped not only by reproductive biology but also by institutional and managerial conditions. Strengthening technical capacity, improving reproductive management, and integrating ET programs into regional livestock innovation systems are essential to enhance the effectiveness and sustainability of reproductive biotechnology in developing dairy sectors.

Journal Galung Tropika

Growth Response of Bileh Fish Juveniles (Rasbora sp.) Reared at Different Temperatures

Determinants of Embryo Transfer Success in Tropical Dairy Cattle: Integrating Reproductive Performance and Institutional Factors