Punjab University Journal of Zoology

15-19

Authors: Naryan C. Rooj

Morphological and histological structure of the respiratory organs with special reference to mouth, gill-openings, paired and unpaired fins, gills have been studied in detail. Four pairs of gills are not much developed. However, the region of the gill-head is provided with many taste buds forming a layer which are chemical detectors for food and water. Mucous gland cells also have formed a well developed middle layer, and the inner layer has formed by well developed abductor muscles. Primary lamellae are pointed at their tips, provided with two rows of moderately developed secondary lamellae in which thicker water blood diffusion barrier (2.25 µm) in comparison to other denizen, Garra lamta (1.75 µm) are present.

37-40

Authors: M.R. Mirza, Islam Ali And M.N. Javed

The fish fauna of the river Kurram and its tributaries in the Kurram Agency has been discussed. Labeo calbasu (Hamilton), Racoma labiata McClelland, Shistura punjabensis (Hora), Glyptothorax kashmirensis Hora and G. naziri Mirza and Naik have been recorded for the first time from this river. Tor putitora (Hamilton) and Cyprinion watsoni (Day), previously recorded from Kurram Agency, have not be collected

45-52

Authors: Shahid Hasnain and Anjum Nasim Sabri

From the effluents of Comfort Chemicals, a bacterium, AnFe-6, which could deter FeCl3 up to 2500 µg ml-1 was isolated. It had circular, convex, entire, off-white opaque colonies. Cells of AnFe-6 were Gram-negative, motile, pleomorphic, rods. It confers resistance to antibiotics, ampicillin (Ap) and chloramphenicol (Cm) and other metallic salts (Ba+2, Zn+2, Ni+2, Co+2, Cu+2, Hg+2, Mn+2 and Sn+2). However it was sensitive to kanamycin (Km), tetracycline (Tc) and streptomycin (Sm) antibiotics and Hg+2 salt. It favours neutral to alkaline pH (7.0 – 7.5) for its growth. It could respire anaerobically, had oxidase and urease activity. AnFe-6 could produce acid from arabinose, glucose and rhamnose. The isolate gave positive results for ONPG, Lysine decarboxylase, gelatin hydrolysis, ornithine decarboxylase and arginine dihydrolase tests. On the basis of these characters the isolate could be affiliated to family Vibrionaceae. By the gel electrophoresis of total cell lysate, no plasmid band was detected in this strain, but conjugation experiments revealed the presence of transferable iron resistance marker, genetic determinant for which has to be established. Minimum of 8 hours were required to establish mating aggregates. Conjugal transfer of genetic element carrying iron resistant marker was affected by donor and recipient proportion, temperature as well as pH of mating mixture. 25 oC inconcomitant with pH 8 showed synergistic response for conjugal transfer.

63-68

Authors: Muhammad Saeed Akhtar, Muhammad Irshad and Amjad Rafooq

Wooden blocks of Magnifera indica were treated with different concentrations (0.1%, 0.2%, 0.4%, 0.8%) of dieldrin and Lorsban. Blocks treated with each insecticide were segregated into two groups, i.e. leached and unleached. Lorsban was found more effective than dieldrin in protecting wooden blocks from attack of Microcerotermes championi Snyder, during short term laboratory experiments.