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The aim of this study was to characterise physical and biochemical aspects of semen as well as to investigate the fine structure of spermatozoa of the Himalayan snowtrout Schizothorax plagiostomus Heckel, 1838 using scanning and transmission electron microscopy. The species breed twice in a year and semen was collected during both seasons, i.e. from 24 males in February and March, 2015 and from 30 males in September and October, 2015. Size of the fish ranged from 13.5 to 36 cm in February-March and 12.3 to 38 cm in September-October. The mean milt volume (ml), sperm density (×1010 ml-1) and spermatocrit (%) values were 2.25±1.26, 2.22±0.53 and 78.87± 8.25 in February-March and 2.12±1.25, 2.12±0.52 and 75.54±8.23 in September-October respectively. Biochemical parameters of seminal plasma viz., total protein (g dl-1), carbohydrates (mg dl-1) and total lipids were 0.312±0.05, 1.348±0.07 and 26.4±2.23 in February-March and 0.340±0.05, 1.34±0.1 and 26.4±3.19 in September-October respectively. Scanning and transmission electron microscopy studies of sperm revealed that the sperm was composed of an ovoid shaped head without acrosome, ellipsoidal midpiece with mitochondria and tail or flagellum. Flagellum had a typical 9+2 axoneme arrangement. The mean length (μm) of head, midpiece, flagella and total length of sperm were 1.82±0.24, 0.35±0.07, 20.18±0.79 and 22.3±3 respectively. For both the breeding seasons, sperm motility decreased significantly with time post-activation.

The ecological diversity of insects and its predators like amphibians are important determinants in ecological balance.  A total of 1,222 prey items in 84 specimens were examined to contribute the understanding of the diets of three Duttaphrynus species, viz., himalayanus, melanostictus, and stomaticus from Uttarakhand, the western Himalaya, India.  Gut content analysis of three bufonids revealed acceptance of a wide range of terrestrial insects and other invertebrates as their food.  The index of relative importance indicated that the most important preys were Formicidae, Coleoptera and Orthoptera.  Duttaphrynus melanostictus had the broadest dietary niche breadth, followed by D. himalaynus and D. stomaticus.  The wide prey spectrum well indicates that these species are the generalist and opportunist invertebrate feeder.  Information pertaining to the food spectrum analysis contributes to understanding the ecological roles and used as a baseline data for future successful amphibian conservation and management programs in the Himalayan ecosystem.

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Abstract:The present study was carried out to investigate the comparative seasonal distribution and relative abundance of fish fauna of streams Bachan Gad of river Alaknanda and Kakda Gad of river Mandakini of Mid-himalayan Ganga river System. Total length of the Bachan Gad is 14.5 km from origin to the confluence at main river Alaknanda with an altitudinal variation from 605.94 to 1418.23m (a.s.1), whereas, total length of the Kakda Gad is 15.5 km. from origin to confluence at main river Mandakini with altitudinal variation from 984.50 to 1993.70 m (a.s.1). Total 23 species from Bachan Gad and 20 fish species were identified from Kakda Gad. The differences in the availability of fish-fauna were directly related to the nature of the profile and slope of tributaries; which affects the migration and breeding grounds of the fishes inhabited in the main river Alaknanda and Mandakini of Ganga river system. Variation in the availability of fishes has been recorded from different sites of the stream. In streams and rivers the changes take place along their length is directly related to the eco-physico-chemical nature (water depth, current, substratum etc). All these factors which change along the length of streams are also the factors which control the distribution of the various sections of the biotic fauna and flora.