Sequential changes in lactate,isocitrate, and malate dehydrogenases in mice exposed to technical grade hexachlorocyclohexane (BHC) and their possible relationship to liver tumors

Hexachlorocyclohexane (BHC) was fed at a 500-ppm-dose level in diet to pure inbred Swiss mice for 2, 4, 6, and 8 months. Later BHC was discontinued for 4 months and subsequently the animals were refed BHC for 1 month. The protein, lactate dehydrogenase (E.C.1.1.1.27), isocitrate dehydrogenase (E.C.1.1.1.42), and malate dehydrogenase (E.C.1.1.1.37) were studied from liver. The liver weight as percentage of body weight was also determined. The results showed an increase in the liver weight/body weight ratio and a decrease in protein and all three enzymes after BHC feeding for the different time intervals. The discontinuation of BHC in the diet resulted in the reversion of values of the above parameters toward the normal and after refeeding BHC for 1 month, the decreased values, as seen after initial BHC feeding, were again observed. This indicates that the changes in the values of lactate dehydrogenase, isocitrate dehydrogenase, and malate dehydrogenase are associated with hexachlorocyclohexane feeding in the diet. The significance of these changes is discussed.     

Impact of iron stress on biomass,yield, metabolism and quality of potato (Solanum tuberosum L.)

In order to study the influence of variable iron on biomass, economic yield and role of iron in potato (Solanum tuberosum) cv. Chandramukhi metabolism, plants were grown in refined sand at variable iron ranging from 0.001 to 2.0 mM. Exposure of potato plants to Fe stress (i.e. a Fe concentration different from 0.1 mM) shows retarded growth, decreased chlorophyll concentration and Hill reaction activity, induced changes in enzyme activities and concentration of Fe and Mn. The visible symptoms of iron deficiency appeared on day 15 at 0.001 mM Fe as chlorosis of young leaves. The excess of iron (at >0.1 mM Fe) appeared later, after 25 days and the chlorosis was observed on older leaves. Both deficiency (0.001 mM) and excess (>0.1 mM) of iron reduced the tuber yield, deteriorating its quality by lowering the concentration of sugars, starch and protein nitrogen and increasing the accumulation of non-protein nitrogen and phenols in tubers.     

Carbon isotopic signature of CO2 emitted by plant compartments and soil in two temperate deciduous forests

? Context

The carbon isotope composition of the CO₂ efflux (δ¹³C_E) from ecosystem components is widely used to investigate carbon cycles and budgets at different ecosystem scales. δ¹³C_E, was considered constant but is now known to vary along seasons. The seasonal variations have rarely been compared among different ecosystem components.

? Aims

We aimed to characterise simultaneously the seasonal dynamics of δ¹³C_E in different compartments of two temperate broadleaved forest ecosystems.

? Methods

Using manual chambers and isotope ratio mass spectrometry, we recorded simultaneously δ¹³C_E and δ¹³C of organic matter in sun leaves, current-year twigs, trunk bases and soil in an oak and a beech forest during 1 year.

? Results

In the two forests, δ¹³C_E displayed a larger variability in the tree components than in the soil. During the leafy period, a pronounced vertical zonation of δ¹³C_E was observed between the top (sun leaves and twigs with higher values) and bottom (trunk and soil with lower values) of the ecosystem. No correlation was found between δ¹³C_E and δ¹³C of organic matter. Causes for these seasonal variations and the vertical zonation in isotope signature are discussed.

? Conclusion

Our study shows clear differences in values as well as seasonal dynamics of δ¹³C_E among different components in the two ecosystems. The temporal and local variation of δ¹³C_E cannot be inferred from organic matter signature or CO₂ emission rates.     

Genetic analysis of growth and egg production traits in synthetic colored broiler female line using animal model

Tropical Animal Health and Production - Variance and genetic parameters were estimated for growth and production traits of synthetic broiler female line (PB-2) using REML animal model to delineate...     

Feeding value of rice distiller’s dried grains with solubles as protein supplement in diet of laying hens

A feeding trial of 10 weeks duration was undertaken on laying hens (n = 240) to evaluate feeding value of rice distiller’s dried grains with soluble (rDDGS) with or without enzyme supplementation (α-amylase, β-glucanase, xylanase, carboxymethylcellulase, pectinase, proteinase, α-galactosidase, β-galactosidase, lipase, and phytase), following 4 × 2 factorial design, on egg production, nutrient utilization, and cost economics of egg production. The birds were randomly assigned to eight dietary treatments with 30 birds/treatment. The birds were housed individually in layer cages and each bird was taken as an experimental unit. Eight experimental diets were prepared by incorporating four levels (0, 50, 75, and 100 g/kg) of rDDGS with and without enzyme supplementation. The results revealed a significant (P < 0.01) increase of egg mass, feed intake, egg production, and body weight gain in dietary treatments with up to 75 g rDDGS though the values were statistically similar to the hens fed 100 g rDDGS. Enzyme supplementation resulted in significant (P < 0.01) improvement of egg mass, egg production, feed conversion ratio (FCR) per dozen eggs, FCR per kilogramme egg mass, and net FCR. The significantly (P < 0.01) higher yolk index was observed at 100 g rDDGS level, while shell thickness improved significantly (P < 0.01) up to 75 g rDDGS level. No significant effect of rDDGS inclusion was observed on shape index, albumin index, and Haugh unit. Enzyme supplementation significantly improved the shell thickness and yolk colour of eggs. Nitrogen, calcium, and phosphorus retention and dry matter metabolizability did not show any significant treatment effects. There was significant (P < 0.01) reduction in feed-cost per kilogramme egg mass or per dozen eggs with the increased DDGS levels and dietary enzyme supplementation. It was concluded that rDDGS can be used up to 100 g/kg diet of laying hens along with enzyme supplementation for better productivity of layer hens.

     

Acacia nilotica-based silvipastoral systems for resource conservation and improved productivity from degraded lands of the Lower Himalayas

High population density and unscientific land use practices have induced severe land degradation in the fragile Lower Himalayan ecosystem of India. Land cover management has been an effective strategy in managing land degradation through the reduction of water, soil and nutrient losses and improvement in soil fertility and quality. Acacia nilotica (Acacia)-based silvipastoral systems with five intercrops, viz., Eulaliopsis binata (bhabbar), Saccharum munja (munj), Vetiveria zizanioides (vetiver), natural grasses and no grass, were evaluated in a long-term study in degraded bouldery lands in Haryana state of India. All grasses resulted in a reduction of soil, water and nutrient losses and improved microbial properties. However, their association adversely affected the growth of Acacia, and the decline varied with grass species. After 11 years of establishment, sole Acacia plantation had the maximum height (7.58 m), diameter at breast height (dbh) (21.32 cm) and crown spread (7.41 m). Munj produced the highest biomass under Acacia, but most adversely affected its growth, resulting in minimum survival (48 %), height (7.07 m), dbh (16.23 cm) and crown spread (6.57 m). Yield of all the grasses increased during the initial 5–6 years, but declined sharply thereafter, with the maximum decline in bhabbar. Detailed investigations established that the sharp decline in survival and growth of bhabbar was due to shade and not because of nutrient competition or allelopathy. Acacia + V. zizanioides proved the most effective silvipastoral system for resource conservation and biomass production. It also provided the highest NPV (Rs 1.88 lakhs ha^?1), B:C (2.37) and IRR (24.70 %) as compared to Rs 6,998 ha^?1, 1.05 and 8.76 % under pure Acacia plantation, respectively.     

Reproductive biology of the carp, Labeo bata (Ham.) from the River Kali,India

Spawning in Labeo bata occurs during July and August. Each individual spawns only once, with the onset of spawning directly dependent on the monsson season. Its success depends upon the access of gravid fish to a suitable spawning ground. The average fecundity is 192 785.     

Identification of barley strains with improved amino acid balance

Summary Four barley strains viz. 1098–2, 1098–7, 1098–9 and 733–6, obtainedfrom the progeny of the crosses, Jyoti x Hyproly and Vijay x Hiproly which showed an increase in the grain protein content and an improvement in amino acid balance, were identified.     

Lacticin 481: in vitro reconstitution of lantibiotic synthetase activity

The lantibiotic lacticin 481 is synthesized on ribosomes as a prepeptide (LctA) and posttranslationally modified to its mature form. These modifications include dehydration of serines and threonines, followed by intramolecular addition of cysteines to the unsaturated amino acids, which generates cyclic thioethers. This process breaks eight chemical bonds and forms six newbonds and is catalyzed by one enzyme, LctM. We have characterized the in vitro activity of LctM, which completely processed a series of LctA mutants, displaying a permissive substrate specificity that holds promise for antibiotic engineering.