Demographic and competition studies on <Emphasis Type="Italic">Brachionus ibericus</Emphasis> and <Emphasis Type="Italic">Proales similis</Emphasis> in relation to salinity and algal (<Emphasis Type="Italic">Nannochloropsis oculata</Emphasis>) density

We isolated the rotifers Brachionus ibericus and Proales similis from the sediment of shrimp tanks and studied their individual demographic characters and competition between them at two food levels (0.25?×?10⁶, 1.00?×?10⁶ cells ml^?1 of Nannochloropsis oculata at 25 °C) and salinities ranging from 10 to 30‰. Our hypothesis was that growth rates would be higher with increasing food levels and salinities. Observations were taken twice a day for life table studies and daily once for population growth experiments. Using survivorship and fecundity data, we derived various life history variables. Although the average life span (7.6?±?0.4 days) and gross reproductive rate (33.8?±?2.9 neonate female^?1 day^?1) of B. ibericus were higher than those of P. similis (average life span 5.4?±?0.6 days and gross reproductive rate 13.0?±?0.6 neonate female^?1 day^?1), the population growth experiments showed that P. similis had higher r values (0.32?±?0.005 day^?1) than B. ibericus (0.23?±?0.002 day^?1) at 1.0?×?10⁶ cells ml^?1 of N. oculata. The rotifer P. similis was more adversely affected due to the presence of B. ibericus than vice versa. The data are important for developing techniques for a large-scale culture of these rotifers as food in aquaculture.     

SCC <Emphasis Type="Italic">mec</Emphasis> typing and antimicrobial resistance of methicillin-resistant <Emphasis Type="Italic">Staphylococcus aureus</Emphasis> (MRSA) from pigs of Northeast India

Staphylococcus aureus is one of the most important pathogens of both humans and animal. Methicillin-resistant Staphylococcus aureus (MRSA) is an important human pathogen that causes serious infections both in hospitals and communities due to its multidrug resistance tendency. This study was undertaken to characterize the MRSA isolates from pigs and to determine the antimicrobial resistance of these isolates. Forty nine MRSA strains (one strain per positive pig) isolated from pigs of Northeast India were characterized by SCCmec typing and antimicrobial resistance. The overall prevalence of MRSA was 7.02 % with the highest prevalence recorded in pigs aged 1–3 months (P = 0.001) and in nasal samples (P = 0.005). Two SCC mec types (type III and V) were found in Indian pigs with predominance of type V. All isolates were resistant to penicillin. Seventeen resistance groups were observed where 87.75 % isolates showed multidrug resistance (showed resistance to three or more classes of antimicrobials). The most predominant resistance pattern observed was Oxytetracycline + Penicillin + Sulfadiazine + Tetracycline accounting 12.24 % of the isolates. The present study contributes to the understanding of characteristics and antimicrobial resistance of porcine MRSA isolates which in turn will help in devising strategy for the control of this pathogen. Findings of the study also throw light on multidrug resistance MRSA and emphasize the need for judicious use of antimicrobials in animal practice.     

Protective properties of Leucas lavendulaefolia extracts against D-galactosamine induced hepatotoxicity in rat

Different extracts of the leaves of Leucas lavendulaefolia were tested against D-galactosamine (D-GalN) induced liver toxicity in rats. The methanol extract (100 mg/kg, p.o.) which exhibited significant hepatoprotective activity seems to support the claim of folk medicine.     

Mineralogy of two red soil (Alfisol) profiles of mysore state,India

Quantitative mineralogical composition of the clay fractions of two red soil (Alfisol) profiles developed on gneissic rocks in Mysore, India, is discussed in relation to the genesis of these soils. Data on the mineralogy of their silt and sand fractions are also presented. Both the silt and clay fractions are kaolinitic and contain considerable amorphous material. A possible weathering sequence of transformation of the minerals, with probable mechanisms involved, is suggested.     

Functional response of Ameca splendens (Family Goodeidae) fed cladocerans during the early larval stage

We studied the functional response of the goodeid Ameca splendens , an endangered species from rivers Ameca and Teuchitlán (Jalisco, Mexico), from birth until 8 weeks old. The cladocerans, Alona glabra adults, Simocephalus vetulus neonates, Ceriodaphnia dubia adults, Daphnia pulex juveniles and Moina macrocopa adults were used as prey. The prey densities, depending on the species, ranged between 0.25, 0.5, 1.0, 2.0, 4.0, 6.0, 8.0, 16.0 and 32 ind. mL⁻¹, with four replicates at each density. We found that all functional responses were Type II. During the feeding period of 30 min, the fish larvae consumed about 600 individuals of the smallest prey A. glabra (450 μm). The consumption of larger prey (<1.0 mm) such as S. vetulus, C. dubia, D. pulex and M. macrocopa ranged between 150 and 200 prey larva⁻¹ during the feeding trials. Our study shows that A. splendens reached maximal prey consumption at around 4 weeks of age, after which there was no increase in prey consumption during the feeding period with age until the end of the study period of 8 weeks. Our study indicates that prey digestion rather than handling time determines the functional response in this fish species and that M. macrocopa is most suited as live food for A. splendens .     

Development of a radioimmunoassay procedure for aflatoxin B1 measurement

A radioimmunoassaay (RIA) procedure to measure aflatoxin B(1) (AfB(1)) in agricultural commodities was developed. AfB(1) oxime derivative was synthesized, characterized, and used for preparation of (125)I-labeled AfB(1). Antiaflatoxin B(1) serum was raised in-house using AfB(1)-bovine serum albumin conjugate as immunogen. The assay system was optimized in the range of 0.2-5 ng/mL, using a liquid phase (PEG) as well as a solid phase (coated polystyrene beads) separation system. Inter-assay and intra-assay variations, recovery, and parallelism studies validated the assay. AfB(1) analysis was carried out in nearly 130 samples of different agricultural commodities. The correlation coefficient was determined using commercial ELISA and in-house-developed RIA methods.     

Study of dimethoate bioaccumulation in liver and muscle tissues of Clarias batrachus and its elimination following cessation of exposure

Abstract: Dimethoate accumulation in liver and muscle tissues of a fresh-water fish, Clarias bactrachus L., was measured by gas liquid chromatography. Fish were exposed to a sub-lethal concentration of the pesticide in the laboratory water tank for a period of eight days. The accumulation increased up to two days, followed by decrease on the 4th and 8th days of exposure in both liver and muscle tissues. Maximum accumulation was found in liver. After eight days of exposure, fish were released into pesticide-free water to study the rate of loss of the pesticide. It was found that liver and muscle tissues were cleared of dimethoate after four and eight days respectively.