Penaeus monodon larvae can be protected from Vibrio harveyi infection by pre‐emptive treatment of a rearing system with antagonistic or non‐antagonistic bacterial probiotics

This study shows that the disease resistance and survival rate of Penaeus monodon in a larval rearing systems can be enhanced by supplementing with antagonistic or non‐antagonistic probiotics. The antagonistic mode of action of Pseudomonas MCCB 102 and MCCB 103 against vibrios was demonstrated in larval mesocosm with cultures having sufficient concentration of antagonistic compounds in their culture supernatant. Investigations on the antagonistic properties of Bacillus MCCB 101, Pseudomonas MCCB 102 and MCCB 103 and Arthrobacter MCCB 104 against Vibrio harveyi MCCB 111 under in vitro conditions revealed that Pseudomonas MCCB 102 and MCCB 103 were inhibitory to the pathogen. These inhibitory properties were further confirmed in the larval rearing systems of P. monodon. All these four probionts significantly improved larval survival in long‐term treatments as well as when challenged with a pathogenic strain of V. harveyi MCCB 111. We could demonstrate that Pseudomonas MCCB 102 and MCCB 103 accorded disease resistance and a higher survival rate in P. monodon larval rearing systems through active antagonism of vibrios, whereas Bacillus MCCB 101 and Arthrobacter MCCB 104 functioned as probiotics through immunostimulatory and digestive enzyme‐supporting modes of action.     

A rare case of globosus amorphus in a goat

We present a case of globosus amorphus delivered from a goat and subjected to radiography and histological examination. Radiography revealed a lack of development of any organ system; histological sections showed evidence of lymphoid aggregations, mononuclear infiltrations, blood capillaries, and dense fibroblasts.     

Assessment of suitability of two serotype A candidate vaccine strains for inclusion in FMD vaccine in India

The recent type A foot and mouth disease virus field isolates recovered in India are shown to be antigenically quite divergent from the in-use vaccine strain (IND 17/82), warranting the selection of a suitable vaccine strain which can cover this diversity in antigenic spectrum. In earlier studies employing neutralization test with anti-146S rabbit sera raised against eight candidate vaccine strains, IND 81/00 and IND 40/00 belonging to genotype VII were found to offer the best antigenic coverage. In order to assess the credibility of IND 81/00 and IND 40/00 as vaccine strains, 17 recent isolates received during 2005-2006 and representative isolates from older genotypes were subjected to two-dimensional micro-neutralization assay using bovine convalescent serum (against IND 81/00 and IND 40/00) and bovine vaccinate serum (against IND 40/00). From the results it is evident that both the isolates IND 81/00 (antigenic relationship 'r-value' >0.40 with 86% of isolates) and IND 40/00 ('r-value' >0.40 with 78% of isolates) show nearly equal antigenic relatedness with the recent field viruses and hence both of these are effective vaccine candidates in present context. Though very limited in its extent, these useful data obtained with antisera raised in homologous host system are logical extension of the on going quest for the appropriate vaccine strain and circumvents species disparities in the immune recognition of epitopes.     

Methods to improve the hatchability of checked chicken eggs

1. The hatchability of checked Leghorn and broiler parent hatching eggs was significantly improved by shell treatment: smearing with synthetic adhesive resin (Fevicol), or pasting cellophane tape or insulation tape over the checked portion of the shell. 2. Shell damage reduced hatchability by increasing evaporative loss, leading to embryonic dehydration. 3. Relative chick weight, expressed as a percentage of egg weight was lower in untreated checked eggs but comparable between intact and shell-treated hatching eggs. 4. The cost of chick production can be reduced by shell treatment of checked hatching eggs, especially in broiler parent eggs.     

Influence of age,sex and rearing systems on Toll-like receptor 7 (TLR7) expression pattern in gut,lung and lymphoid tissues of indigenous ducks

1. The objective of the experiment was to determine the influence of age, sex and rearing system on Toll-like receptor 7 (TLR7) gene expression in gut, lung and lymphoid tissues and physiological responses to stress in male and female indigenous ducks of Tamil Nadu, India.

2. A total of 36 ducks (12 males and 24 females) were obtained from local farmers and tissue samples of gut tissues (duodenum, jejunum, ileum and caecum), lymphoid organs (spleen and bursa) and lungs were collected in RNAlater solution followed by RNA extraction.

3. After normalisation to β-actin (endogenous control) qPCR analysis identified a significant effect of age, sex and rearing system on TLR7 expression in the ducks.

4. A significant up-regulation of TLR7 expression was observed in lungs, duodenum, jejunum, ileum and caecum of sexually mature (45 wk) compared with that of immature ducks (16 wk). Among sexes, male ducks had significantly higher TLR7 expression than female ducks.

5. Age and sex interactions were significant in lungs, duodenum, jejunum and caecum. Ducks reared in an extensive housing system showed significantly higher TLR7 expression in bursa, lungs, duodenum, ileum and caecum compared to intensively reared ducks. There were no effects of age, sex and rearing systems on TLR7 expression in the spleen.

6. The heterophil-to-lymphocyte ratio and serum corticosterone were higher in ducks reared on an intensive system compared with ducks from an extensive rearing system.     

Performance of mango based agri-horticultural models under rainfed situation of Western Himalaya, India

A total of 15 years of experimentation period (1995–2010) was divided into two phases. In the first phase (1995–2005), five mango based agri-horticultural models (AHM) viz. Mango + cowpea–toria, mango + cluster bean/okra–toria, mango + sesame–toria, mango + black gram–toria and mango + pigeon pea in addition to sole mango plantation (no intercrop) and in second phase (2005–2010), two mango based AHM (mango + colocasia and mango + turmeric) in addition to sole mango (no intercrop) were studied. The mean maximum cowpea equivalent yield (t ha^?1) was harvested from cowpea (1.84) followed by okra (1.21), black gram (1.11), sesame (0.68) and mean minimum with pigeon pea (0.58). The crop yield reduction among the mango based AHM was observed from third year to tenth year. The positive correlation was found between light transmission and intercrops yields amongst all models during both phases. However, the correlation between mango canopy spread and intercrop yields shown negative trends. The yield reduction in intercrops varied from 37.0–52.6 % during first phase and 20.6–23.5 % during second phase of experimentation compared to sole crop. The results revealed that the fruit based AHM were effective in improving fruit yields of the mango. The mean maximum fruit yield of mango (7.02 t ha^?1) was harvested with cowpea–toria crop rotation followed by black gram–toria (6.59 t ha^?1) and minimum fruit yield (5.76 t ha^?1) realized with sole mango tree during first phase (1999–2005). Likewise, mean maximum fruit yield (13.71 t ha^?1) from mango tree was obtained in the turmeric block followed by (13.00 t ha^?1) in colocasia block and minimum fruit yield with sole mango tree (11.86 t ha^?1). All the treatments of AHM recorded higher soil moisture as compared to sole mango plantation during both phases. The moisture retention under different AHM was in the order of cowpea (13.32 cm) > black gram (13.29 cm) > pigeon pea (13.27 cm) > okra (12.42 cm) > sesame (12.17 cm) > sole mango (11.62 cm) during first phase, whereas moisture retention was observed in the order of turmeric (14.20 cm) > colocasia (14.01 cm) > sole mango (12.60 cm) during second phase. The cowpea–toria crop rotation with mango gave maximum benefit: cost ratio followed by okra–toria under rainfed conditions. Besides economic viability of cowpea–toria with mango, this system had improved tree growth as well as fruit yield of mango. In the second phase, mango + turmeric yielded more benefit than mango + colocasia system. In the first phase, the mango + cowpea–toria system improved organic carbon, total nitrogen, phosphorus, potash and reduced pH by 49.0, 56.3, 48.6, 58.5 and 11.6 %, respectively as compared to initial values whereas mango + turmeric system increased organic carbon, nitrogen, phosphorus, potash and reduction in pH by 51.0, 45.0, 29.7, 29.0 and 3.4 %, respectively over initial values within soil depths of 0–30 cm during second phased. Mango based AHM is recommended for adoption with selective intercrops up to 15 years of age of mango plantation for multiple outputs and good economic viability without impairing site fertility.     

Phytoremediation of Mixed Soil Contaminants

Tests were conducted to study the influence of non-ionic surfactants Triton X-100 and Tween 80 on the removal of mixed contaminants from a sandy soil using phytoremediation. Cd(II) and Pb(II) were used to form the inorganic contaminant, while used engine oil was selected to form the organic contaminant. The Indian mustard (Brassica juncea) plant was the plant chosen for phytoremediation of the sandy soil that contained the mixed contaminant. Thirty days after the plants were grown in the greenhouse, surfactants were applied to test pots in which the soil had been spiked with 50 mg kg⁻¹ of CdCl₂, 500 mg kg⁻¹ of PbCl₂ and 500 mg kg⁻¹ of used engine oil. Two control tests were conducted in this study. Planted and unplanted control tests were conducted using soil without surfactants. Following these tests, the tests were completed using the plants and surfactants at different concentrations. Test results showed that Triton X-100 and Tween 80 at concentrations higher than their critical micellar concentration enhanced Cd(II) and Pb(II) accumulation in the plant roots. Further, test data showed that translocation of contaminants to plant shoots occurred for Cd(II) but not for Pb(II). At the same concentrations, Tween 80 was more effective than Triton X-100 in facilitating rhizodegradation of used engine oil. This study demonstrates that simultaneous phytoremediation of Pb(II), Cd(II) and oil can be enhanced by using non-ionic surfactant Tween 80. Leaching test results indicated that the enhanced phytoremediation could remove the mixed contaminants safely from the point of view of limiting groundwater contamination.