Natural growth
The growth rate of striped catfish is relatively high (Lazard, 1998). At the end of the egg-yolk stage, the fry is from 1–1.1 cm in total length, and after 14 days, it reaches 2.0–2.3 cm in length and 0.52 g in weight. The 5-week-old juvenile is 1.28–1.5 g in weight and 5–6 cm in length. This species can reach 0.7–1.5 kg after a year and 3–4 kg after three to four years. During the early stages, striped catfish will rapidly increase in length; but when the fish attains about 2.5 kg in weight, it begins to accumulate body fat. The correlation between age and weight of wild striped catfish shows that the fish grows rapidly during the early years, but that growth then slows in the following years, such that a 10-year-old fish shows almost no weight gain. A 9-year-old pond-cultured fish may weigh 16.5 kg; however, at 11 years its weight remains only 15–17 kg (Vietnamese Ministry of Fisheries, 1991). The Vietnamese Ministry of Fisheries (1991) has reported that the correlation between length and weight of wild-caught striped catfish in Cambodia is:
Male fish: Wt = 0.023648 L∞2.86
Female fish: Wt = 0.02238 L∞2.76
Where: Wt: body weight (g) (maximum weight of fish was 17 kg)
L∞: total length (mm) (maximum length of fish was 1 200 mm)
The lipid composition of the fish's body is directly proportional to the growth of fish. In the first year of life, the lipid composition increases dramatically, while in subsequent years almost no increase is observed. For example, a fish weighing 11.2 g has a body lipid composition of 0.99 percent and a fish of 560 g has 1.6 percent lipid, but a 3-year-old fish weighing 3.62 kg has a body lipid of 1.62 percent. The lipid composition in a male fish is higher than that in a female fish (Tran, 1994).
Growth in culture conditions
The growth of farmed fish (Table 3) depends greatly on culture density and the quality and quantity of the feed supplied. The growth of striped catfish in cages was recorded by Tran et al. (2006), who observed that fish with an initial weight of 102 g reached the weight of 1 016 g after six months. According to Nguyen (2011), the correlation of fish growth and culture period was y=0.0862e0.0126x (r2=0.9477) (y=fish weight in kg and x=day of culture) (Figure 2).
