Volume 94, Issue 2
April 1985, pages 87-171
pp 87-91 April 1985
Laboratory studies on growth and reproduction of Diaphanosoma Senegal Gauthier show that this species has a life span of 18–7 days. Three preadult and sixteen adult instars were recorded at a temperature range of 28–30°C. Maximum body size is attained at the end of its life-cycle and the growth increment is more during preadult instars. The present observations are compared with other laboratory studies on tropical South Indian cladocerans.
pp 93-97 April 1985
The toxicity of warfarin (0·-025 %), bromadiolone (0·-005 %) and brodifacoum (0·-005 %) to the Indian field mouse,Mus booduga Gray was determined. A single feeding of bromadiolone or brodifacoum resulted in 83% mortality, while the same mortality was obtained with warfarin only after 6 days of continuous feeding. A single day feeding of a single dose chronic poison was effective againstM. booduga than multiple dose chronic rodenticide.
pp 99-110 April 1985
The effects of starvation on the metabolic rate and the glucose, glycogen and total lipid contents in the freshwater prosobranch snailBellamya bengalensis (Lamarck) have been investigated. Starvation influenced the metabolic rate ofB. bengalensis. Although there was an initial increase, the metabolic rate of both the sexes decreased in the later stages of starvation. There was a marked difference in the utilization of nutrient stores between male and female snails starved for 55 days.
pp 111-116 April 1985
Increase in effluent concentration reduced the period of limb bud emergence and tail resorption; it also produced elevated values for length of limbs, tail and body weight of adultR. malabarica. Analysis of variance (Anova test) confirmed that time (week) has pronounced effect on morphological parameters (P < 0·05) than treatment (P > 0·05).
pp 117-122 April 1985
Preferences of rodents toward cereal baits have been studied in relation to the availability of food from their natural habitat in crop fields of groundnut (Arachis hypogaea) and lentil (Lens culinaris). The experimental area was infested by three rodent species—Bandicota bengalensis, Taxera indica andMus sp. At the podding stage of groundnut crop they showed a poor response towards plain bait of whole wheat grains, the consumption of which increased significantly after addition of arachis oil at 1% concentration. The withdrawal of oil from the bait had no significant effect on its daily consumption by the rodents. In paired bait tests in podding groundnut crop, the addition of oil significantly increased the bait consumption of wheat and millet grains. The differences between daily consumption of millet grains became more significant when the bait station pairs were shifted to growing lentil crop which reflect the effect of environment on the feeding responses of rodents. Laboratory tests withB. bengalensis andT. indica trapped from the experimental fields confirmed the results of field studies that addition of oil in the cereal bait enhance bait consumption.
pp 123-127 April 1985
Social stress was induced inBandicota bengalensis by staging 10 min encounters in neutral area between male-male, male-female and residents-intruder male for 9 continuous days. On the 10th day changes in the weight, ascorbic acid, and cholesterol levels of liver were estimated. In submissive males, females of male-female encounter and intruders, adrenals hypertrophied. Liver weight remained unaltered. Ascorbic acid levels increased in both members of heterosexual pair, residents and intruder but decreased in subordinates compared to controls. Cholesterol increased in subordinate males and stressed females.
pp 129-138 April 1985
Using the indigogenic technique for localizing the non-specific esterases, the complete nerve arrangement inFischoederius elongatus andGastrothylax crumenifer, the paramphistome parasites in the rumen of cattle, has been visualized. InF. elongatus, of the three pairs of anterior nerves given off from the cerebral ganglia, two are ventral and one is dorsal in disposition. The nerves running posterior from the cerebral ganglia include two pairs of ventral nerves and one of dorsals. Throughout their course the two ventrals of either side are joined to each other by several loop-like connectives. InG. crumenifer, the overall nerve arrangement is somewhat similar to that inF. elongatus; the connectives joining the posterior ventrals of each side are not loop-like. The course of all the nerves and the innervation to the various parts of the body is traced in both the species.
pp 139-143 April 1985
The function of the midgut gland of the scorpionHeterometrus fulvipes has been investigated in relation to hypoxia. Regional differences in the midgut gland became apparent, one part being more active metabolically than the other. It is concluded that the midgut gland might be serving as the liver, as gluconeogenesis is predominant.
pp 145-151 April 1985
A histological study of the male reproductive system undertaken in the present study has been concentrated on trematodes with a cirrus sac. Special attention has been focussed on the terminal genitalia. Five species of trematodes,Fasciola gigantica, Acanthocolpus liodorus, Stephanostomoides dorabi, Rhynchocreadium singhia andProsorhynchus manteri have been considered for the present study.
pp 153-160 April 1985
The effects of blinding onChanna punctatus exposed to LD 14:10, 12:12, 9:15, continuous dark (DD) and continuous light (LL) was studied during the winter quiescent phase of the annual reproductive cycle. Ovarian weights of blinded fish exposed to LD 14:10, 12:12 or LL were higher than those exposed to LD 9:15 or DD. However, no effects of blinding on testicular recrudescence under any photoperiodic regime were observed. Studies suggest that in addition to the eyes, other extraocular photoreceptors are also involved for gathering information on day length.
pp 161-167 April 1985
Influence of three food plants,viz Memordica charantia, Luffa acutangula, andTrichosanthus anguina on the food utilization and chemical composition ofHenosepilachna septima has been studied. The rate of conversion and conversion efficiencies were higher inT. anguina fed beetles. The rate of conversion was positively correlated with the protein content of the food plants. The organic constituents ofH. septima specially protein and lipid increased when fed on the different food plants. Greater increase of all the organic constituents occurred when the insect was fed on the nutrient richT. anguina than when fed on other food plants.
pp 169-171 April 1985