The effects of salinity on growth of goldfish, Carassius auratus and crucian carp, Carassius carassius

Abstract

The effects of four different salinities (SW, 50% SW, 100% SW and 150% SW) on specific growth rate, weight gain, food intake and survival of goldfish and crucian carp were investigated for 20 days. Both species were respectively adapted to water source, which has salinity of 8 ppt in the experimental unit for one month and then transferred to SW (8 ppt), 50% SW (12 ppt), 100% SW (16 ppt) and 150% SW (20 ppt) experimental treatments. Four goldfish fish and three crucian carp fish were placed in each aquarium. They were fed with commercial feed (Tetra Pond) to satiation twice a day and individually weighed at weekly interval. The final weight of the goldfish reared in the SW (938 ± 486 mg) and 50% SW (723 ± 269 mg) was significantly larger than that of fish reared in the 100% SW (475 ± 114 mg) and 150% SW (106 ± 318 mg). The specific growth rate was the highest in the SW (SGR: 0.53 ± 0.270% day-1) and the lowest in the 150% SW (SGR: 0.06 ± 0.195% day-1). Food intake was higher in the first three treatment groups (10.33 ± 0.572; 10.86 ± 0.917; 10.17 ± 0.767 g, respectively) than in the 150% SW (7.75 ± 1.612 g). Survival was not significantly different in the four salinity treatments (81.20 ± 23.94 ton 100.00 ± 0.00%). The final weight of the crucian carp breeding in the SW (860 ± 220 mg) and 50% SW (848 ± 394 mg) were significantly higher than the other two treatment groups. It was the worst in the 150% SW (-15 ± 903 mg). Specific growth rate was higher in the SW (SGR: 0.22 ± 0.040% day-1) and 50% SW (SGR: 0.30 ± 0.103% day-1) than the other two treatment groups. It was the lowest in the 150% SW (-0.06 ± 0.300% day-1). Food intake was higher in the first three treatment groups (8.70 ± 1.352; 7.25 ± 0.540; 7.06 ± 0.647 g, respectively) than in the 150% SW (5.60 ± 1.875 g). Survival was significantly influenced in the 150% SW (83.33 ± 19.24%). In conclusion, both species can be transferred to brackish water having not more than 8 ppt salinity. The maximum salinity tolerances of goldfish and crucian carp were 20 ppt. These findings are important in aquarium fish industry.

Growth and osmoregulatory response of Cyprinus carpio haematopterus (Amur carp) reared in inland saline water

“…Statistical analysis of the data revealed significant difference in all the treatments for final weight and mean weight gain. Küçük (2013) reported that freshwater fish generally grow well in both freshwater and low salinity environments and growth declines with increasing salinity which supports the finding of present study. The findings related to growth of the present study were also supported by other workers on different freshwater fishes (Wang et al 1997, Rani and Gulia 2015, Upadhyay 2015, Abdullah 2016).…”

ẢNH HƯỞNG CỦA ĐỘ MẶN ĐẾN TỐC ĐỘ SINH TRƯỞNG, TỶ LỆ SỐNG VÀ HỆ SỐ CHUYỂN HÓA THỨC ĂN CỦA CÁ BỐNG BỚP (Bostrychus sinensis) GIAI ĐOẠN GIỐNG

“…trồng thuỷ sản ở miền Bắc Việt Nam trong thời gian gần đây[21], nuôi vỗ thành thục trong điều kiện nhân tạo[12]. Việc xác định được độ mặn thích hợp để ương cá có vai trò hết sức quan trọng vì nó ảnh hưởng trực tiếp đến sinh lý của cá, làm giảm tốc độ sinh trưởng, tỷ lệ sống, phản ứng miễn dịch và khả năng chống chịu dịch bệnh của cá[17]. Ảnh hưởng của độ mặn đến sinh trưởng của cá bống bớp đã được một số tác giả trong và ngoài nước nghiên cứu như Đỗ Mạnh Dũng và Ngô Anh Tuấn [1] và Zhang và Huang[22].…”