M. Rajkumar

Effect of cholymbi on growth, proximate composition, and digestive enzyme activity of fingerlings of Long whiskered catfish, Mystus gulio (actinopterygii: siluriformes: bagridae)

Background. Long whiskered catfish, Mystus gulio (Hamilton, 1822), enjoys a high consumer preference and market demand in many Asian countries including India. However, the growth of this fish is very slow under normal aquaculture conditions. The non-hormonal growth promoter—cholymbi—which contains minerals and the essential amino acids lysine and methionine, is widely used in livestock and poultry as a feed additive to improve growth and survival. Supplementing feed with cholymbi may increase the growth and survival of Mystus gulio. Materials and methods. A feeding trial was conducted to determine the effect of dietary cholymbi supplementation on growth, survival, and feed conversion ratio of long whiskered catfish fingerlings. Four isoproteic diets (crude protein 37%) were formulated to incorporate cholymbi at 0%, 0.25%, 0.50%, and 0.75% diet. The diets were fed to triplicate groups of fish twice daily to supply 5% of the total body weight per day for 120 days. Water quality parameters were maintained within the range suitable for catfish growth. Results. Weight gain (WG), protein efficiency ratio (PER) and feed conversion ratio (FCR) were all affected by diet (P < 0.01, 0.001, and 0.001, respectively). The group fed the 0.50% cholymbi diet had the highest WG and PER and the lowest FCR, although not significantly different from the group fed the 0.25% cholymbi diet. There was no significant difference (P > 0.05) in carcass proximate composition of catfish fed diets containing these different levels of cholymbi. Gut protease, amylase, and lipase activities were stimulated by dietary inclusion of cholymbi at all levels compared to control. Conclusion. As cholymbi is a newly introduced dietary supplement for fish, more research is needed to optimize its supplementation to improve growth, PER, FCR, and survival of long whiskered catfish. Until then, a diet with 0.50% cholymbi can be recommended to improve the aquaculture production of this species.

Seasonal variations in the structure of copepod assemblages in tropical marine and estuarine waters, Coleroon, south-east India

A twelve-month investigation was undertaken on how copepod community structure varied in relation to environmental factors in the Coleroon estuary, south-east India. Sampling was monthly, from Station 1 in the sea to Station 4 in the Vettar backwaters. Canonical correspondence analysis (CCA) was applied to elucidate the environmental factors affecting the copepod community. A total of 104 copepod species in 38 genera and 26 families were recorded, with the Calanoids, Acartia erythraea and Oithona brevicornis being the most dominant. At all four stations, both these species loaded near the intercept of CCA axes 1 and 2, perhaps reflecting that they were autochthonous. Most species occurred in distinct seasonal patterns. Abundances ranged from 13x10(3) to 215x10(3) (ind.m(-3)). Coleroon waters showed high diversity (bits/ind.), from 5.29 at Station 3 to 4.97 at Station 4. Abundance correlated positively with temperature and salinity and negatively with rainfall, dissolved oxygen concentration (DO) and pH. Species diversity correlated strongly with abundance (P<0.01). Abundance and diversity were highest during the summer, and both correlated positively with salinity. Temperatures (air and water), salinity, pH and DO varied in the ranges 26-36 degrees C, 25-34.2 degrees C, 9-38, 7.0-8.7 and 3.0-6.8mll(-1), respectively. Nitrate, nitrite, phosphate and silicate (mu M) varied in the ranges: 4.7-64.5, 0.4-14.1, 0.2-12.9 and 9.3-148, respectively.

Wound healing activity of an herbal ointment containing the leaf extract of Ziziphus Mauritiana Lam.

A large number of plants are used by folklore traditions in India for treatment of cuts, wounds and burns. Particularly, the leaves of Ziziphus mauritiana Lam. (Family: Rhamnaceae) have been practiced on wounds for healing. The aim of the present investigation was to assess the in vivo wound healing efficacy of prepared topical formulation of 5% w/w ethanolic extract ointment and 5% w/w of aqueous extract ointment and nitrofurazone ointment (0.2% w/w) on excision wound model in Wistar albino rats. The effect produced by ointment, in terms of wound contracting ability, wound closure, decrease in surface area of wound, tissue regeneration at the wound site in treated Wistar albino rats shows that proliferation of epithelial tissue promotes angiogenesis, multiplication of fibrous connective tissue due to treatment with Z. mauritiana. Acute toxicity studies revealed the non-toxic nature of Z. mauritiana. Ethanolic extract ointment (5% w/w) of Z. mauritiana manifested 99% wound contraction on the 16th day. These results were also comparable to those of a standard drug, nitrofurazone. Topical formulation with 5% w/w ethanolic extract promoted wound contraction and reduced the wound closure time, so increase in tensile strength and wound contraction shows the wound healing potential of Z. mauritiana. Thus, the present study supports the scientific rationale for the traditional use of this plant in the management of wounds.