Comparison of the dot-immunobinding assay with the complement fixation test for the detection of Brucella antibodies in sheep

A dot-immunobinding assay (DIA), using as antigen a sonic extract of Brucella abortus dotted on nitrocellulose bound to a plastic strip, was employed for the detection of Brucella antibodies in 666 sheep sera. The results were compared with the complement fixation test (CFT). All the 242 sera belonging to two flocks were found to be negative by DIA. CFT was negative in 239 cases, whereas three samples showed anti-complementary activity. Of the 424 sera from the remaining three flocks, 98 were positive by both tests and six were positive in DIA, but negative in CFT. In addition, 14 of the 19 anti-complementary sera were also positive by DIA.     

Hepatoprotective activity of Calotropis procera flowers against paracetamol-induced hepatic injury in rats

Hydro-ethanolic extract (70%) of Calotropis procera flowers was prepared and tested for its hepatoprotective effect against paracetamol-induced hepatitis in rats. Alteration in the levels of biochemical markers of hepatic damage like SGPT, SGOT, ALP, bilirubin, cholesterol, HDL and tissue GSH were tested in both treated and untreated groups. Paracetamol (2 g/kg) has enhanced the SGPT, SGOT, ALP, bilirubin and cholesterol levels and reduced the serum levels of HDL and tissue level of GSH. Treatment with hydro-ethanolic extract of C. procera flowers (200 mg/kg and 400 mg/kg) has brought back the altered levels of biochemical markers to the near normal levels in the dose dependent manner.     

Antioxidant system of Litomosoides carinii and Setaria cervi: effect of a macrofilaricidal agent.

Filarial parasites, Litomosoides carinii and Setaria cervi, showed great susceptibility to the oxidants generated in vitro by the xanthine/xanthine-oxidase system. In order to counteract such injurious effects, both the filariids possessed an active antioxidant enzymes system. Superoxide dismutase, catalase and glutathione peroxidase were detected in appreciable amounts but glutathione reductase and glucose-6-phosphate dehydrogenase in very low quantities. The former three enzymes were also found to be released by the parasites into the ambient medium. The released enzymes may be responsible for scavenging the host-generated oxidants present in the immediate surroundings of the parasites and thereby enabling them to live comfortably in the host. This Institute-based antifilarial agent namely Compound 82/437 which is 2,2'-dicarbomethoxylamino-5,5'-dibenzimidazolylketone, markedly inhibited catalase and glutathione peroxidase of both L. carinii and S. cervi. The compound, therefore, appears to render the filariids prone to H2O2 toxicity leading to penultimate damage.     

Natural Polyesters: Dufour's Gland Macrocyclic Lactones Form Brood Cell Laminesters in Colletes Bees

Bees in the genus Colletes make their brood cells in the ground and coat them with a highly resistant, waterproof, transparent membrane. This membrane is a polyester constructed mainly from 18-hydroxyoctadecanoic acid and 20-hydroxy-eicosanoic acid, which are stored as their corresponding lactones in the Dufour's gland of the bee. When lining the cells, the bee secretes its glandular content, and the membrane is apparently a product of polycondensation reaction of its contents. This appears to be the first report of a naturally occurring linear polyester. The term laminester (lamina approximately layer + ester) for this class of compounds is proposed.     

Alkali bees: response of adults to pathogenic fungi in brood cells

Female alkali bees (Nomia melanderi) opened sealed cells containing brood infested with Aspergillus flavus, A. tamarii, Fusarium solani, Rhizopus sp., or Mucor sp. and filled them with compact soil, thus reducing fungus sporulation. Such awareness of the condition of sealed brood is hitherto unknown among solitary bees.     

Nitrogen contribution to wetland rice by green manuring with Sesbania spp. in an alkaline soil

Summary Two annual species of Sesbania, S. aculeata and Sesbania sp. PL Se-17, were field evaluated as green manure for wetland rice in an alkaline soil. The two species were raised as a catch crop during summer in a wheat-rice rotation, and added as 24.7 and 20.8 t ha^–1 of green matter, 116 and 98 kg N ha^–1, respectively, after 45 days of growth. For the optimum green manuring effect on rice grain yield and N uptake, S. aculeata required 5 days of decomposition (after turning in and before rice transplantation), whereas no decomposition period was necessary for Sesbania sp. PL Se-17. The effect on grain yield and N uptake of rice was equivalent to an application of 122 and 78 kg ha^–1 of chemical N, for the two species, respectively. There was no residual effect of the green manuring on the soil N status after rice harvest.     

Decomposition of paddy straw in soil and the effect of straw incorporation in the field on the yield of wheat

In a laboratory experiment, incorporation of paddy straw in soil immobilized native as well as added fertilizer N and about half of the immobilized N was mineralized after 90 days of straw incorporation. Straw and N application alone or in combination increased biomass carbon, phosphatase and respiratory activities of the soil. Microbial biomass carbon and phosphatase activity were maximum at 30 days of straw decomposition. In field trials, incorporation of paddy straw 3 weeks before sowing of wheat significantly increased the wheat yield at Sonepat district in a clay loam soil while no such beneficial effect was observed in a sandy loam soil at Hisar.