Compensatory growth response of sailfin molly, Poecilia latipinna (Lesueur, 1821) to starvation and refeeding

Compensatory growth response and body composition of male sailfin molly, Poecilia latipinna subjected to short-term starvation and subsequent feeding were studied for 54 days. Four feeding schedules were used in this study: C, Control (were fed to apparent satiation throughout the experiment); T1, Treatment 1 (3 days Starvation and 6 days refeeding); T2, Treatment 2 (6 days Starvation and 12 days refeeding); T3, Treatment 3 (9 days Starvation and 18 days refeeding). At the end of the experiment, the starved fish gained a body weight comparable to that of the control fish. There were no differences in condition factor, specific growth rate and weight gain between the starved and control fish at the end of the experiment. Daily feed intake was significantly higher in T3 than that in the control. Short-term starvation did not influence protein, lipid and ash contents. Moisture content of T2 and T3 fish were significantly higher than those of T1 and control fish. The results indicated that complete compensation occurred in the starved fish and that this species can tolerate to short term starvation without any significant effects on growth and feeding performance

N-(2-Thienylmethyl­ene)-2-(2-{[2-(2-thienylmethyl­eneamino)phen­yl]sulfan­yl}ethyl­sulfan­yl)aniline

The asymmetric unit of the title compound, C24H20N2S4, contains one half-mol­ecule: a crystallographic centre of inversion is located at the mid-point of the two central C atoms. The thio­phene ring is oriented at a dihedral angle of 60.64 (3)° with respect to the benzene ring. In the crystal structure, π–π contacts between thio­phene rings [centroid–centroid distance = 3.581 (1) Å] may stabilize the structure. A weak C—H⋯π inter­action is also present

Effects of different levels of dietary taurine amino acid on Rosy Barb (Pethia conchonius) pigmentation

Taurine (2 amino ethane sulfonic acid), is a semi-essential amino acid and an end product of the sulfur amino acid metabolism. The aim of this study was improving Rosy barb (Pethia conchonius) pigmentation. The fish (average weight 32 ± 7 mg and length 12.83 ± 1.82 mm) were divided into five different groups including control (basic diet without taurine and astaxanthin) and four different levels of taurine (0, 100, 250 & 500 mg/kg diet) with constant amount of astaxanthin (100 mg/kg diet) and fed for 60 days. The pigmentation analysis was done using digital camera photography and whole body biochemical carotenoid analysis and showed that the fish fed on 100 + 250 mg/kg of astaxanthin & taurine respectively had the highest levels of pigmentation. Adding taurine up to 250 (mg/kg diet) caused increasing total carcasses lipid, plasma triglyceride, cholesterol, LDL & HDL levels in compression to the fish fed on control diet (p<0.05). It could be concluded that dietary taurine supplementation could affect fish lipid metabolism and improve astaxanthin absorption, which lead to better pigmentation in Rosy barb

Larval rearing and ontogeny of digestive enzyme activities in yellowfin seabream (Acanthopagrus latus, Houttuyn 1782)

The present research was conducted to provide insight into digestive larval capacity in Acanthopagrus latus larvae from hatching up to 30 days after hatching (DAH). Newly hatched larvae were stocked into six 300-L cylindrical polyethylene tanks at a density of larvae 50 larvae/L and reared by means of the green water system using Nannochloropsis oculata (0.5 × 106/mL). After mouth opening, larvae were fed with rotifers (5–16 individual/mL) from 2 to 20 DAH; then, Artemia nauplii (0.5–3.0 individuals/mL) were offered to larvae from 18 to 30 DAH, meanwhile a commercial microdiet was offered to larvae from 25 to 30 DAH. Larval performance in terms of growth and survival, and the assessment of the activity of selected digestive enzymes ontogeny of digestive enzymes activities was evaluated in larvae sampled at 0 (hatching), 7, 15, 22 and 30 DAH. Larvae showed an exponential growth characterized by two different growth stanzas, a first one characterized by slow growth rates comprised between hatching to 15 DAH (4.7 ± 0.2 mm), followed by a period of faster growth rates between 16 and 30 DAH (7.5 ± 0.6 mm). The activities of the brush border (alkaline phosphatase, ALP) and cytosolic (leucine-alanine peptidase, LAP) enzymes, as well as those of the pancreatic ones like total alkaline proteases, bile salt-activated lipase and α-amylase were detected from the mouth opening stage. Total activities of pancreatic and gastric enzymes increased with larval growth showing an enhancement of digestive capacities with larval age and size. The intestinal maturation in A. latus as assessed by the ratio of AP to LAP did not occur as expected by end of the first month of life suggesting the complete establishment of digestive luminal processes may take place at older ages. This study related to the growth patterns and ontogenic changes in activity of pancreatic, gastric and intestinal enzymes in A. latus and their nutritional regulation may be considered as the first step for improving the larviculture, as well as assessing and refining the nutritional requirements during the larval and early juvenile stages of this sparid species.info:eu-repo/semantics/acceptedVersio

Comparison of the use of taurine in combination with feed and sprays in growth and feeding performance and physiological responses of Asian sea bass (Lates calcarifer)

The aim of this study was to compare the effects of adding taurine to diet as a mixture with feed and also as spray on growth and feeding performance, body composition and physiological responses of Asian sea bass, Lates calcarifer (13.62 ± 0.2 g). This study was carried out in a completely randomized design as three treatments with triplicates. Fish were fed with feed containing 0 (control group), 10 g/kg taurine in feed as mixture (treatment M) and 10 g/kg as spray on feed (treatment S) for 6 weeks. At the end of the experiment, final weight, weight gain, specific growth rate and feed conversion ratio were significantly higher in treatment S compared to the control and treatment M (p 0.05). The obtained results indicated that dietary taurine did not enhance Asian sea bass blood biochemical factors and non-specific immune response (p>0.05). Overall, it can be concluded that feeding Asian sea bass with the diet supplemented by 10 g taurine as spray for a period of 6 weeks enhances the growth and feeding performance

Effects of different levels of dietary butyric acid on some growth performance, immunity and digestive enzymes activity of yellowfin seabream (Acanthopagrus latus Houttuyn, 1782)

This study was conducted to evaluate the effects of different dietary levels of butyric acid on growth performance, immunity and digestive enzyme activities in yellowfin seabream (Acanthopagrus latus) (8.59 ± 0.33 g) at the period of 60 days. After 2-week adaptation, 120 fish with a density of 10 fish/tank in a completely randomized design were distributed to 12 tanks. Fish were fed with 4 levels of butyric acid including zero (control), 2.5 (T1), 5 (T2) and 10 g/kg (T3) of diet 2 times per day. The results showed that different levels of butyric acid in diet had significant effects on growth performance and nutritional indices compared to the control (p0.05). The food conversion ratio in control group was significantly higher than in the other treatments (p0.05). In conclusion, butyric acid, especially at the level of 10 g/kg of diet, displayed positive effects on the growth, immune indices and enzyme activities in yellowfin seabream

Compensatory growth response of sailfin molly, Poecilia latipinna (Lesueur, 1821) to starvation and refeeding

Compensatory growth response and body composition of male sailfin molly, Poecilia latipinna subjected to short-term starvation and subsequent feeding were studied for 54 days. Four feeding schedules were used in this study: C, Control (were fed to apparent satiation throughout the experiment); T1, Treatment 1 (3 days Starvation and 6 days refeeding); T2, Treatment 2 (6 days Starvation and 12 days refeeding); T3, Treatment 3 (9 days Starvation and 18 days refeeding). At the end of the experiment, the starved fish gained a body weight comparable to that of the control fish. There were no differences in condition factor, specific growth rate and weight gain between the starved and control fish at the end of the experiment. Daily feed intake was significantly higher in T3 than that in the control. Short-term starvation did not influence protein, lipid and ash contents. Moisture content of T2 and T3 fish were significantly higher than those of T1 and control fish. The results indicated that complete compensation occurred in the starved fish and that this species can tolerate to short term starvation without any significant effects on growth and feeding performance

Weaning strategies affect larval performance in yellowfin seabream (Acanthopagrus latus)

A 30-day study was carried out to determine the influence of different weaning strategies (WS) on growth and survival rates, stress resistance, digestive enzyme activities and whole body fatty acid profiles in yellowfin seabream (Acanthopagrus latus) larvae. Thus, eight WS were designed by combining live foods (LF) (rotifers and Artemia) and a microdiet (MD) (Gemma Micro™, Skretting). In the control group (100 LF), larvae were fed only LF (100%), including enriched rotifers (from 2 to 20 days post hatching, dph) and Artemia (nauplii + enriched metanauplii, from 18 to 30 dph). The other treatments were based on different proportions of LF with the MD: 75LF-25MD, 50LF-50MD, 25LF-75MD and 100 MD in which 25, 50, 75 and 100% of LF that applied in the control group were replaced with a fixed ration of MD, respectively. In addition, for determining the appropriate time of weaning, three WS were applied including: sudden weaning (SW): larvae were weaned on to MD with only rotifer from 2 to 5 days post hatch (dph); early weaning (EW): larvae were weaned on to MD with only rotifer from 2 to 14 dah and late weaning (LW): larvae were weaned on to MD with rotifer (from 2 to 14 dph) and Artemia nauplii (from 12 to 20 dph). Larvae were hand-fed with the MD hourly from 08:00 h to 18:00 h (11 times a day). Results showed that the lowest survival rates were found among larvae from 100MD (1.5%) and SW (1.9%) groups, whereas the highest survival rates were found in larvae from 100LF (31.0 ± 1.7%), 75LF-25MD (34.7 ± 4.5%) and 50LF-50MD (36.2 ± 4.0%). Larvae from the 50LF-50MD group showed the highest resistance against air exposure (70.0%) and osmotic stress (100.0%) challenges. At the end of the trial, larvae from 100LF, 75LF-25MD, 50LF-50MD and LW groups showed higher growth performance than the other groups. At 30 dph, larvae from the LW group had the highest level of alkaline phosphatase to leucine-alanine peptidase ratio, while those from the 100MD, SW and EW treatments showed the lowest ones. The fatty acid profile of larvae reflected that of the diet. In particular, larvae from 100MD and SW groups had generally lower levels of n-3 long chain polyunsaturated fatty acids compared to the other treatments. In conclusion, results of the present study indicated the time of weaning and proportion of LF and MD remarkably affect larvae performance in terms of growth, survival, digestive function and stress tolerance. In addition, the replacement of LF with MD up to 50% after mouth opening of larvae neither have detrimental effects on growth, survival and digestive enzymes activities, meanwhile enhanced stress resistance of A. latus larvae.info:eu-repo/semantics/acceptedVersio