Lamproglena notopterai sp. nov.- a copepod parasite from a freshwater fish of Sindh, Pakistan

The study was conducted at the Central Experimental Station, Philippine Rice Research Institute, Maligaya, Science City of Munoz, Nueva Ecija, Philippines during the wet season to determine the suitable stocking density(s) for better growth and yield of fish under rice-fish production systems. Recovery rate of GIFT tilapia in different stocking densities ranged from 75.74 to 83.47%. Among different treatments, rice +5,000 fingerlings/ha and rice +10,000 fingerlings/ha resulted in the highest recovery rate of 83.33% and 83.47%, respectively. The lowest recovery rate of 75.75% was obtained from rice +20,000 fingerlings/ha, but similar to that was obtained (78.56%) from rice +15,000 fingerlings/ha. Significantly higher rate of gain in body weight and that of specific growth rate were recorded in the treatment from rice +5,000 fingerlings/ha, while other treatments resulted in similar absolute and specific growth rate. Fish yield increased significantly with relatively higher stocking densities, but higher densities produced maximum number of smaller fishes and also lower recovery rate.

Plerchis heterorchis N. sp. (Digenea: Acanthocolpidae Luhe, 1909) from fishes Lutjanus johnii and Otolithus argenteus of Karachi coast, Pakistan

A new species of trematodes Pleorchis heterorchis is described from the fishes Lutjanus johnii and Otolithus argenteus of Karachi coast. The new species is characterized by having a lanceolate body with a notch at the middle of the posterior end of the body. Body surface is smooth, ventral sucker rounded, situated at the anterior middle region of the body, pre-pharynx is well developed, widened posteriorly, pharynx muscular, oesophagus short, intestine H-shaped with anterior arms much shorter than the posterior, intestinal bifurcation almost in the middle of fore body, anterior caeca wide and short extending as far as anterior limit of pharynx. Posteriorly caeca reach to posterior end of the body with no lateral out pocketing. Testes 44 in number, intercecal arranged in 2 parallel rows, sub-globular, entire to slightly irregular, almost of same sizes extending immediately from posterior of the ovary to anterior of excretory vesicle. Cirrus pouch overlaps the ventral sucker, extends into hind body, terminating above the ovary, containing bipartite seminal vesicle, pars prostatica and ejaculatory duct. Genital pore behind the intestinal bifurcation and pre-acetabular. Ovary pre-testicular, consists of 16 follicles of varying sizes. Vitellaria lateral, follicular, extending from post bifurcal to posterior extremity. Excretory vesicle reaches to the posterior level of last pair of testes.

Effect of stocking density on survival and growth of mud crablings, Scylla sp. in laboratory conditions

Mud crablings, Scylla sp. were reared, for a period of six weeks in fiberglass aquarium under laboratory conditions, to determine the effect of four different stocking densities of 1, 2, 3 and 4 crabling/l of water on their survival and growth. Salinity of water was maintained at 25 ppt throughout the rearing period. Stocking rates of 1, 2, and 3 crabling/l resulted in a similar (p>0.05) survival rates of 75, 74, and 83.5%, respectively, that of 4 crabling/l resulted in significantly lower (p<0.05) survival rate of 56%. No significant difference was observed among different stocking densities in average growth of carapace length (CL), carapace width (CW) and body weight (BW).

Influence of a fish bacterium Lactobacillus sp. on the production of swordtail xiphophorus helleri (Heckel 1848)

The influence of a fish gut bacterium Lactobacillus sp on the production of swordtail Xiphophorus helleri was studied for a period of one year. The Lactobacillus sp P21 produced bacteriocin-like inhibitory substance and exhibited wide spectrum of action against Aeromonas hydrophila, Bacillus spp, Pseudomonas spp and Citrobacter freundi in vitro. The growth performance of X. helleri reared in the presence of Lactobacillus P21 at 106/ml rearing water was better than the control. The total plate counts, total MRS agar counts and the counts of motile aeromonads, presumptive pseudomonads, lactose fermenters and lactose non-fermenters in the gut of probiotic group were comparatively low than the control. On day 60 the count of Lactobacillus sp P21 was observed to be log 5.28/g in the gut of X. helleri indicating colonization of this bacterium in the gastrointestinal tract. The fecundity of X. helleri was in the range of 9-134. On average, it produced from 39.42±18.72 fry/female in control group to 53.00±23.57 fry/female in probiotic group. The increase in average fecundity in probiotic group over the control group was about 25%. There existed significant difference between probiotic group and control in respect of average fecundity/female (p<0.02), average number of fry survived /female (p<0.006) and average number of fry dead/female (p<0.029). The results of the present study demonstrated that the rearing of X. helleri in probiotic-enriched water have growth inducing ability and favourably influenced the reproductive performance in terms of high fecundity, high fry survival, reduced fry mortality and reduced fry deformity.

Effect of feeding bioencapsulated Lactobacillus sp. in live Tubifex sp. on the growth performance of gold fish Carassius auratus (Linnaeus, 1758)

An attempt was made to feed bioencapsulate Lactobacillus sp. in live fish food organism Tubifex for use in the culture of gold fish Carassius auratus. The C. auratus fries when fed with bioencapsulated Lactobacillus sp. in Tubifex showed significant improvement in total wet weight gain (p<0.007) and FCR (p<0.01) compared to control. The specific growth rale and mean survival were slightly higher, although insignificantly (p>0.05) in bioencapsulated Tubifex fed group. None of the bacteriological parameters of the fish gut between the experimental and control groups differed significantly (p>0.05). Lactobacillus sp. was recorded at a level of log 5.11/g on the 90th day of experimentation. When the experimental C. auratus fries were infected with Pseudomonas fluorescents, the bioencapsulated Tubifex fed group resisted the infection. The survival was significantly higher (p<0.05) in bioencapsulated Tubifex fed group (44%) than in control (22%). The C. auratus fed with bioencapsulated Tubifex showed less (55%) signs of tail/fin rot. Likewise, a significant improvement in total wet weight gain (p<0.009), FCR (p<0.01) and SGR (p<0.04) of C. auratus brooder fed with bioencapsulated Tubifex was seen compared to control group fed with depurated Tubifex.

Feasibility study of biofuel production from freshwater fern, Azolla sp in Anzali Wetland

Production of bioethanol through acidic and enzymatic hydrolysis of aquatic Azolla sp., as a new source of bio-mass, has been performed, as a means to control increasing growth and reducing undesirable effects of this plant in Anzali lagoon. After sampling, drying and crushing, Azolla was hydrolyzed, using diluted acid and enzyme. Diluted acid hydrolysis was done using both autoclave and a high-pressure system (Batch Synth® Microwave synthesizer). The effects of temperature and time (in autoclave) and concentration of acid (in both) were compared. Cellubrix®, a ommercial cellulase source, was used for enzymatic hydrolysis process. The amounts of reducing sugars, glucose and furfural, released from hydrolyzate, were measured. To produce alcohol, Sacchromyces cerevisiae (to ferment sixcarbon sugars), Zygowilliopsis californica and Pichia stipitis (to ferment five-carbon and sixcarbon sugars) were used. Maximum amounts of glucose (4.83% w/w) and reducing sugars (14.15% w/w) were obtained using acid hydrolysis in autoclave. In the microwave oven, maximum glucose (5.04% w/w) and reducing sugars (13.27 w/w) were obtained at 180 and 200 °C, respectively. Under these conditions, maximum produced furfural was 1.54 g/L. The difference between amounts of furfural obtained from acid hydrolysis of Azolla in microwave oven compared to autoclave was statistically significant. Amounts of alcohol produced and its yields were 3.99 g/L and 33.13% for S. cerevisiae in 48 hours, 3.73 g/L and 30.45% for Pichia stipites in 48 hours, and 3.73 g/L and 30.45% for Z. californica in 24 hours after inoculation, respectively, with significant differences. Statistical comparison of results showed significant differences (P<0.05) in glucose production, at different conditions. Amounts of reducing sugars and glucose increased after optimization of levels of acid, time, and temperature. The overall optimum released sugar and glucose were obtained with 1.67% (w/v) acid using autoclave. Higher temperatures in microwave oven caused a significant increase (P<0.05) in furfural. Furfural severely inhibits fermentation. Hence, regarding the issues of energy consumption and time, amounts of inhibiting substances and sugar production, autoclave is found to be superior to the high temperature and pressure, generated in microwave oven, for hydrolyzing Azolla. Furthermore, given the amounts of Azolla in Anzali lagoon, it may be recommendable to use this plant as a biomass resource.

Effect of two green algae species (Chlorella sp. & Scenedesmus obliquus) enriched with B group vitamins on food chain of Rutilus frisii kutum (Kamensky, 1901) fry

The Effect of two freshwater green algae species Chlorella sp. & Scenedesmus obliquus enriched (from the beginning of culture and after 96 hours) with different dosages of B group vitamins (0, 0.5, 1, and 2 ml of enriching solution per each liter of algae medium) on fecundity of Daphnia magna and growth of Rutilus frisii kutum fry were investigated in a research from spring, 2008 to autumn, 2009. First, each of the green algae species were cultured purely and massively in the Zander (Z-8+N) medium and then the nutritional value (the amount of protein, lipid, and carbohydrate) of enriched algae were meausered. In this study, enriching of Chlorella sp. & S. obliquus with a suitable mix of B group vitamins significantly improved their nutritive value. So the highest amount of nutritional value of Chlorella sp. was obtained because of enriching with dosage 0.5 ml.l-1 (366.654Kcal) and for Scenedesmus obliquus with dosage of 1 ml.l-1 (376.95Kcal). The acquired amount from control group showed an increase of respectively 42% and 11%. According to the results, increased dosages of enriching solution caused Daphnia fecundity to increase (at both stages : enrichment from the beginning of culture and after 96 hours). So the highest average of D. magna reproduction rate was obtained through being fed with Chlorella sp. and S. obliquus enriched with dosage of 2 ml enriching solution per liter of algae medium. The average fecundity of D. magna fed with Chlorella sp. enriched with dosage of 2 ml.l-1 enriching solution from the beginning of culture and after 96 hours was obtained respectively 2.128 ± 0.375 and 2.1 ± 0.69 and the average fecundity of D. magna fed with S. obliquus enriched with dosage of 2 ml enriching solution from the beginning of culture and after 96 hours was obtained respectively 2.128 ± 0.375 and 2.1 ± 0.69 which showed respectively an increase of 61 ٪, 91٪, 77 ٪, and 83٪ in proportion to the acquired amount from control group. When enriching solution was added to either algae culture medium from the beginning of culture, showed statistically significant differences (P<0.05) between dosages of 0 and 2 ml.l-1, 1 and 2 ml.l-1, and 0.5 and 2 ml enriching solution per each liter of Chlorella sp. culture medium and between dosages of 0 and 1 ml.l-1, and 0 and 2 ml enriching solution per each liter of S. obliquus culture medium. The highest average of body weight gain percentage and specific growth rate of kutum fry was obtained respectively 21.19%, 26.63%, 1.92, and 2.34 from the beginning of culture and after 96 hours with dosage of 1 ml B group vitamins per each liter of Chlorella sp. culture medium, which showed respectively an increase of 50%, 70%, 46%, and 62% in proportion to the acquired amount from control group. In the cases which Chlorella sp. were grown in the medium containing vitamin, from point of view of the average percentage of weight and specific growth rate of kutum fry significant differences were observed on the basis of the result of One-way ANOVA between dosages of 0 and 1, 1 and 2 , 0.5 and 1 ml B group vitamins per each liter. The highest average of body weight gain percentage and specific growth rate of kutum fry was obtained respectively 32.02%, 29.42%, 2.78, and 2.34 from the beginning of culture and after 96 hours with dosage of 2 ml B group vitamins per each liter of S. obliquus culture medium, which showed respectively an increase of 32%, 19%, 28%, and 17% in proportion to the acquired amount from control group. In the cases which S. obliquus were grown in the medium containing vitamin, from point of view of the average percentage of weight and specific growth rate of kutum fry significant differences were observed on the basis of the result of One-way ANOVA between dosages of 0 and 1, 0 and 2. According to the results of the present research we can say that considerable enhancement in the quality of the food of D. magna can be made by manipulation of the nutritional value of fresh water unicellular green algae with suitable mixture of B group vitamins, so that both the fecundity of D. magna will increase and the nutritional requirements of the kutum fry will be filled in this way.

Occurrence of Zoothamnium sp. infection in Penaeus monodon (Fabricius, 1798) of the coastal shrimp culture ponds of Cox's Bazar Bangladesh

Penaeus monodon (Fabricius, 1798) is a popular cultivable species and valuable foreign exchange earning item among all the fishery commodities in Bangladesh. At present with semi-intensive and intensive shrimp culture practices, disease is a problem. Protozoan infection, caused by the Zoothamnium sp. is one of the causes of damage in the total production by growth retardation and mortality. No work has yet been done on shrimp disease in Bangladesh. The present account therefore, constitutes the first report on it from the shrimp culture ponds of Cox's Bazar. The present work includes the occurrence and prevalence of protozoan disease, its seasonal variations and level of infestation in different length groups in Penaeus monodon.

First record of a spindle cowry Crenovolva (Ovulidae, Gastropoda) from Bulleji, Karachi, on the gorgonian coral Muricella sp. and with a note on their association

Attached to hard substrata on our shores occur the branching colonies of gorgonian corals of the genus Muricella (Fig. 1A, Pl. 1B, C, D). Since there is no report on this genus from Pakistan this report be taken as the first record from here. The family Ovulidae comprises several hundred species of marine gastropods, all of which appear to be obligate associates of cnidarians as stated by Robertson (1970) and Hadfield (1976); the present ovulid gastropod genus Crenovolva lives exclusively on the gorgonians (Morton, 1989). Tirmizi and Zehra (1984) recorded thirty-two families of gastropods from Pakistan, but not any representative of the Ovulidae, so the material at hand may be the first record from Pakistan. Since we are unable to reach to specific level the material is being reported as unspecified.

Hablando de Ictiólogos Argentinos… Hugo Luis López.

Este es un homenaje realizado bajo mi entera responsabilidad. En mi opinión no puede cerrarse la edición de ProBiota sin publicar un número sobre quien fue su alma mater. En lo personal, hacedor de un humor irónico increíble, aunque melancólico, con tendencia al abatimiento y a hacerse responsable por todo. Mediador, proclive a “poner la oreja”, con actitud democrática hacia sus laderos, otorgando una prudente libertad de acción a quienes trabajaron o trabajan bajo su jefatura. Fiel simpatizante de River Plate, fan de Clint Eastwood y admirador incondicional de Raúl A. Ringuelet a quien estará eternamente agradecido. Si tuviera que definirlo profesionalmente, al margen de su labor académica formal, diría que es un promotor, un luchador y un historiador innato. Generador de ideas, siempre intentó reunir a aquellos científicos de trayectoria con los jóvenes iniciados en el camino de las ciencias, impulsando el trabajo en equipo. Además de su producción a nivel de su especialidad, promocionó el rescate de trabajos ya editados digitalizándolos con el fin de ponerlos a disposición de todo interesado y despertar el interés de quienes no los conocían, especialmente las publicaciones “incunables” como él las denomina. Poseedor de un espíritu inquieto y motivador, en su camino quedaron algunos intentos frustrados por circunstancias ajenas, pero a su vez, muchísimos logros con aire renovador e integrador y con una marcada originalidad. Sería interesante y necesario que alguien más con parecida inquietud, continuara gran parte de esos logros para que no quedaran truncos desperdiciando en parte tanto esfuerzo y constancia. Sólo resta comentar que aunque a veces estuvimos en veredas opuestas siempre nos tendimos la mano en apoyo mutuo. Fuiste mi mejor jefe. Gracias Hugo! Justina Ponte Gómez