• Fisheries and Aquatic Sciences
• /
• v.27 no.9
• /
• pp.565-571
• /
• 2024

Ultrasound images can be utilized as a non-invasive method in the reproductive program. Striped catfish in various gonadal development were examined with a portable Mindray Model Z60Vet using the Convex probe at a frequency of 5 MHz. The results showed that the male gonads of immature striped catfishes were not distinguished from other visceral organs by using an ultrasonic technique. Ultrasound images in ovaries in stages II and III had significant differences. In ovary's group of stage III, the oocyte's dimensions on the ultrasound images were twice bigger than the group of stage II was. Before the premilitary injection, eggs displayed small, smooth, black dots, and 12h after the definitive dose, egg diameters raised twice and had brighter dots on the ultrasound images.

• Ocean and Polar Research
• /
• v.27 no.1
• /
• pp.109-113
• /
• 2005

To facilitate estimation of the barbel size of a striped sea catfish, Plotosus lineatus Thumberg total length (TL) and head length (HL) against body weight (BW), HL against TL, and 1st maxillary barbel $(MxBL_1)$, 2nd maxillary barbel $(MxBL_2)$, 1st mandibular barbel $(MnBL_1)$ and 2nd mandibular barbel $(MnBL_2)$ against HL were regressed. The relationship of TL and HL for BW were described by the equation $TL=50.9373BW^{0.3072}\;(r^2=0.9898)$ and $HL=11.2938BW^{0.3144}(r^2=0.9572)$, respectively. The relationship of HL for TL was described by the linear equation $HL=0.1982TL+2.1996(r^2=0.9568)$. The relationship of each barbel for HL described by the equation of $HxBL_1=0.04420HL+0.3105(r^2=0.9615),\;MxBL_2=0.4592HL+0.5321(r^2=0.9519), MnBL_l=0.4057HL+1.9824 (r^2=0.9465)\;and\;MnBL_2=0.4355HL+1.8010(r^2=0.9429)$. Knowledge of the relative growth patterns about each barbel of this species is important for the propagation of seed as stock for large-scale striped sea catfish culture.

• Fisheries and Aquatic Sciences
• /
• v.27 no.9
• /
• pp.572-579
• /
• 2024

Peptidoglycan is considered a type of prebiotic or immunostimulant. However, the utilization of these substances in aquaculture remains limited, with no reported results in striped catfish. The current study aimed to investigate the effects of dietary supplementation of peptidoglycan on the growth performance and immune status of striped catfish. Fish were fed on diets supplemented with various concentrations of peptidoglycan at 0, 2.5, 5, and 10 g/kg of feed, named to PL0, PL2.5, PL5, and PL10 treatments at 4% of fish weight during 4 weeks. Blood samples were collected after 2 and 4 weeks of experiment (T2 and T4) for hematological indices and immune analyses, including lysozyme and peroxidase activities. Results demonstrated that no significant differences were found in fish growth, survival rate, and intestinal indices. The improvements in feed conversion and protein efficiency ratios were observed in PL2.5-fed fish compared to the control. Peroxidase activity in PL10 group was higher than PL0 at T4 while the highest value of lysozyme activity was recorded in fish fed PL10 at T2. In conclusion, dietary supplementation of peptidoglycan at 2.5 g per kg of diet induced a beneficial effect on feed utilization, while positive influences on immune parameters were recorded in fish fed on a diet added peptidoglycan at 10 g/kg feed.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.40 no.3
• /
• pp.141-146
• /
• 2007

We investigated the reproductive cycle of the striped eel catfish Plotosus lineatus. Specimens were sampled in the coastal waters of Sungsan and Jocheon, east of Jeju, Korea, from September 2001 to August 2002. The gonadosomatic index (GSI) in females and males were reached a maximum in June $(14.18{\pm}10.38)$ and July $(0.35{\pm}0.12)$, respectively. Based on histological observations and GSI variation, the reproductive cycle was classified into the following successive stages: in females, growing (September-April), mature (April-June), spawning (June-July), and degenerative and recovery (July-September) and in males, growing (August-December), mature (September-May), spent (April-July), and degenerative and recovery (June-August). The total length at 100% maturity exceeded 15 cm and the fecundity ranged from 525 to 1176 eggs. The fecundity was correlated positively with total length and body weight. Histological observations of the gonads suggest that this species is a spring-summer spawner with group-synchronous type oocyte development.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.38 no.3
• /
• pp.158-163
• /
• 2005

This paper deals with the histology of the barbels of striped sea catfish, Plotosus lineatus (Thunberg). This fish have eight noticeable barbels of two pairs on their maxillary and mandibular. Each barbel is composed of an epidermis, dermis and a central rod of cartilage. The epidermis in the middle part of the maxillary barbel is thicker than those on other parts, and formed of stratified epithelium which contains many cutaneous taste buds and a few small club cells. Number of taste buds increase on the middle and posterior part of each barbel. The dermis consists of loose connective tissue fibers which encloses blood vessels and bundles of nerve fibers. The barbels of this fish can be categorized into stiff and flexible types and are accessory, feeding and sensory structures. Thus we substantiate that they are gustatory receptor organs for this fish.