Effect of heat exposure on prostaglandin production and expression of COX-2, PGES, PGFS, ITGAV and LGALS15 mRNAs in endometrial epithelial cells of buffalo (Bubalus bubalis).

BACKGROUND: Early embryonic mortality is one of the major intriguing factors of reproductive failure that causes considerable challenge to the mammalian cell biologists. Heat stress is the major factor responsible for reduced fertility in farm animals. The present study aimed to investigate the influence of heat stress on prostaglandin production and the expression of key genes, including COX-2, PGES, PGFS, ITGAV and LGALS15, in buffalo endometrial epithelial cells. METHODS AND RESULTS: Buffalo genitalia containing ovaries with corpus luteum (CL) were collected immediately post-slaughter. The stages of the estrous cycle were determined based on macroscopic observations of the ovaries. Uterine lumens of the mid-luteal phase (days 6-10 of the estrous cycle) were washed and treated with trypsin to isolate epithelial cells, which were then cultured at control temperature (38.5 °C for 24 h) or exposed to elevated temperatures [38.5 °C for 6 h, 40.5 °C for 18 h; Heat Stressed (HS)]. The supernatant and endometrial epithelial cells were collected at various time points (0, 3, 6, 12, and 24 h) from both the control and treatment groups. Although heat stress (40.5 °C) significantly (P < 0.05) increased COX-2, PGES, and PGFS transcripts in epithelial cells but it did not affect the in vitro production of PGF2α and PGE2. The expression of ITGAV and LGALS15 mRNAs in endometrial epithelial cells remained unaltered under elevated temperature conditions. CONCLUSION: It can be concluded that elevated temperature did not directly modulate prostaglandin production but, it promoted the expression of COX-2, PGES and PGFS mRNA in buffalo endometrial epithelial cells.

Spatio-temporal dynamics and distributional trend analysis of African swine fever outbreaks (2020-2021) in North-East India.

African swine fever (ASF) is a highly contagious, notifiable, and fatal hemorrhagic viral disease affecting domestic and wild pigs. The disease was reported for the first time in India during 2020, resulted in serious outbreaks and economic loss in North-Eastern (NE) parts, since 47% of the Indian pig population is distributed in the NE region. The present study focused on analyzing the spatial autocorrelation, spatio-temporal patterns, and directional trend of the disease in NE India during 2020-2021. The ASF outbreak data (2020-2021) were collected from the offices of the Department of Animal Husbandry and Veterinary Services in seven NE states of India to identify the potential clusters, spatio-temporal aggregation, temporal distribution, disease spread, density maps, and risk zones. Between 2020 and 2021, a total of 321 ASF outbreaks were recorded, resulting in 59,377 deaths. The spatial pattern analysis of the outbreak data (2020-2021) revealed that ASF outbreaks were clustered in 2020 (z score = 2.20, p < .01) and 2021 (z score = 4.89, p < .01). Spatial autocorrelation and Moran's I value (0.05-0.06 in 2020 and 2021) revealed the spatial clustering and spatial relationship between the outbreaks. The hotspot analysis identified districts of Arunachal Pradesh, Assam and districts of Mizoram, Tripura as significant hotspots in 2020 and 2021, respectively. The spatial-scan statistics with a purely spatial and purely temporal analysis revealed six and one significant clusters, respectively. Retrospective unadjusted, temporal, and spatially adjusted space-time analysis detected five, five, and two statistically significant (p < .01) clusters, respectively. The directional trend analysis identified the direction of disease distribution as northeast-southwest (2020) and north-south (2021), indicate the possibility of ASF introduction to India from China. The high-risk zones and spatio-temporal pattern of ASF outbreaks identified in the present study can be used as a guide for deploying proper prevention, optimizing resource allocation and disease control measures in NE Indian states.

Effect of α-tocopherol in the vitrification medium on the viability, lipid peroxidation, expression of key developmental, apoptotic and stress-related genes in ovine secondary follicles.

The present study aimed to evaluate the effect of α-tocopherol on viability, lipid peroxidation and the expression of apoptosis, stress and development-related genes in the vitrified sheep secondary follicles. Ovarian secondary follicles (200-300 µm) were isolated and distributed separately to the vitrification treatment and supplemented with 5 mM, 10 mM, 20 mM and 30 mM of α-tocopherol (while the control fresh group was without vitrification and supplementation of α-tocopherol). After a week, the follicles were thawed and evaluated for follicular viability by trypan blue dye exclusion method, lipid peroxidation and gene expression studies. The results showed that the vitrification with 10 and 20 mM of α-tocopherol positively affected (p < .05) the viability of vitrified follicles in comparison with vitrified ones without α-tocopherol but the higher concentration of α-tocopherol, i.e., 30 mM negatively affected the viability (p < .05) in comparison with the 10 and 20 mM of α-tocopherol groups. The malondialdehyde (MDA) levels were significantly (p < .05) higher in the vitrified without α-tocopherol group in comparison to the vitrified with 20 mM of α-tocopherol group. The expression of apoptotic-related gene, BCL2L1 was significantly higher in 10 mM α-tocopherol group compared to the control fresh and CASPASE 3, 9 expressions were significantly higher in the vitrified group when compared to the vitrified with 10 mM α-tocopherol group. Expressions of BAX, BAD, BAK, BMP-15 and GDF-9 showed no significant difference among the groups. The mRNA expression of SOD1 was significantly higher in the vitrified without α-tocopherol group when compared to other groups. We conclude that the supplementation of 10 and 20 mM α-tocopherol in vitrification solution was the efficient vitrification procedure for the vitrification of ovine secondary follicles.

Regulatory role of Wnt signal in the oestradiol synthesis of different size categories of ovarian follicles in buffalo (Bubalus bubalis).

The aim of the present study was to understand the role of Wnt signal in ovarian oestradiol synthesis in various size categories of ovarian follicles. A six-day cell culture system was adopted to test the effect of a Wnt inhibitor i.e. Inhibitor of Wnt response (IWR) on the ovarian granulosa cell oestradiol synthesis and associated genes related to oestradiol synthesis and Wnt signalling (CYP19A1, CCND2, WNT2, FZD6, DVL1, APC, AXIN2, CTNNB1) in buffalo. It was conducted with four groups: Group 1: control, Group 2: control + FSH, Group 3: IWR, Group 4: IWR + FSH. No significant effect of IWR was observed on the ovarian granulosa cell proliferation. No significant difference in the oestradiol levels was found in the spent media harvested after six days of in vitro culture among different groups in small and large-sized ovarian follicles. However, the oestradiol level varied significantly (p < .05) among different treatment groups in medium-sized follicles. The oestradiol level was significantly lower (p < .05) in IWR group compared with the control group and was also significantly lower in IWR + FSH group compared with the FSH group. The Wnt inhibitor had significantly (p < .05) reduced the gene expression of CYP19A1 in large ovarian follicles. Varied effects of IWR-1 and FSH on the expression of other genes were observed. The results indicated that there is a positive role of Wnt signal in oestradiol synthesis in buffalo, but the positive role was more discernible in medium- and large-sized follicles.

Effect of retinol in the vitrification medium on viability of vitrified ovine preantral follicles and expression of key developmental and apoptosis related genes.

BACKGROUND: Vitrification increases the production of reactive oxygen species (ROS) and the antioxidants in the vitrification solution may be beneficial by reducing excessive ROS production. OBJECTIVE: To evaluate the effect of retinol supplementation in vitrification solution on viability, apoptosis and development-related gene expression in vitrified sheep preantral follicles. MATERIALS AND METHODS: Preantral follicles were isolated and randomly assigned into one of five groups: Group1, control fresh preantral follicles; Group 2, vitrification treatment; Group 3, vitrification + 2 µM retinol; Group 4, vitrification + 5 µM retinol; Group 5, vitrification + 10 µM retinol. Preantral follicles were placed in vitrification solutions and then plunged into liquid nitrogen (-196°C). After a week, the follicles were thawed and analyzed for follicular viability by trypan blue exclusion method and for gene expression. RESULTS: Vitrification with 5 µM retinol positively affected viability in comparison with vitrification without retinol (P < 0.05). There was no significant difference in viability among the Group 1, Group 2, Group 3 and Group 5. Expression of apoptotic genes BAX and Casp 3 were higher in the vitrified group, and vitrification with 5 µM retinol (Group 4) is comparable to the control fresh. Expressions of other apoptosis-related genes (i.e., BCL2L1, BAD and BAK) showed significant difference between the control fresh group and the vitrification group with 5 µM retinol. Expression of Annexin5 was also significantly different among various groups. The expression of development competence genes GDF-9 and BMP-15 were higher (P < 0.05) in the Group vitrified with 5 µM retinol. CONCLUSION: The supplementation of 5 µM retinol in vitrification solution was beneficial for the vitrification of ovine preantral follicles.

Copper and Selenium stimulates CYP19A1 expression in caprine ovarian granulosa cells: possible involvement of AKT and WNT signalling pathways.

The role of copper and selenium on activation of estradiol synthesis pathways viz. PKA/AKT/WNT is not clearly elucidated. On this background we attempt to elcuiated the role of copper and selenium on mRNA expression of genes associated with estradiol synthesis in caprine ovarian granulose cell models. Ovarian granulosa cells from medium (3-5 mm) sized follicles were aspirated and distributed separately to different groups. Group I: control, Group II: cupric chloride (Cu: 0.5 mM), Group III: sodium selenite (Se: 100 ng/ml), Group IV: Cu + Se. The cells (105/well) were cultured in 96 well plate in the base culture medium of MEMα comprising of nonessential amino acids (1.1 mM), FSH (10 ng/mL), transferrin (5 µg/mL), IGF-I (2 ng/mL), androstenedione (10-6 M), penicillin (100 IU/mL), streptomycin (0.1 mg/mL) and fungizone (0.625 µl/mL) and insulin (1 ng/mL). The cells were incubated in a carbondioxide incubator (38 °C, 5% CO2, 95% RH). The medium was changed on alternate days and cells were harvested on day 6. Day 6 media was used for estimation of estradiol. The RNA isolated form harvested cells was used for qPCR assay. There was no significant (p > 0.05) difference in estradiol concentration between groups. The mRNA expression of AKT1, CYP19A1, WNT2 & 4, FZD6 and APC2 were significantly (p < 0.05) higher in Cu and Cu + Se groups compared to control. Whereas, the mRNA transcript of DVL1 and CSNK1 was significantly (p < 0.05) higher in Cu + Se group compared to control. Incontrast, no significant difference in mRNA expression of PRKAR1A and CTNNB1 was noticed. Our study support a key role of copper and selenium in activation of AKT and WNT signalling pathway that further lead to increase in the mRNA expression of CYP19A1.

Effect of retinol as antioxidant on the post-thaw viability and the expression of apoptosis and developmental competence-related genes of vitrified preantral follicles in buffalo (Bubalus bubalis).

The present study evaluated the effect of supplementation of retinol in the vitrification solution on the viability, apoptosis and development-related gene expression in vitrified buffalo preantral follicles. Preantral follicles isolated from cortical slices of ovaries were randomly assigned into three groups: Group1-Control fresh preantral follicles; Group 2-Vitrification treatment (Vitrification solution 1 (VS1) -TCM-199 + 25 mM HEPES + Foetal bovine serum (FBS) 10%, Ethylene glycol (EG): 10%, Dimethyl sulphoxide (DMSO): 10%, Sucrose-0.3 M for 4 min; VS2- TCM-199 + 25 mM HEPES + FBS10%, EG:25%, DMSO: 25%, Sucrose:0.3 M for 45 s); Group3-vitrification treatment +5 µM of Retinol. Preantral follicles were placed in corresponding vitrification medium and plunged into liquid nitrogen (-196°C). After a week, the follicles were thawed and analysed for follicular viability and gene expression. There was no significant difference in the viability rates among the Group 1(Fresh preantral follicles) (91.46 ± 2.39%), Group 2 (89.59 ± 2.46%) and Group 3 (87.19 ± 4.05%). There was a significantly (p < .05) higher mRNA expression of BCL2L1, GDF-9 and BMP-15 in the vitrification + retinol group compared with the control group. There was a significantly (p < .05) higher expression of Caspase-3 and Annexin-5 in the vitrification group and Vitrification + retinol group compared with control group of follicles. It is concluded that the supplementation of 5 µM of Retinol in Vitrification solution was an efficient vitrification procedure for the vitrification of buffalo preantral follicles.

First Observation of Multiple Transverse Wobbling Bands of Different Kinds in

We report the first observation of two wobbling bands in ^{183}Au, both of which were interpreted as the transverse wobbling (TW) band but with different behavior of their wobbling energies as a function of spin. It increases (decreases) with spin for the positive (negative) parity configuration. The crucial evidence for the wobbling nature of the bands, dominance of the E2 component in the ΔI=1 transitions between the partner bands, is provided by the simultaneous measurements of directional correlation from the oriented states ratio and the linear polarization of the γ rays. Particle rotor model calculations with triaxial deformation reproduce the experimental data well. A value of spin, I_{m}, has been determined for the observed TW bands below which the wobbling energy increases and above which it decreases with spin. The nucleus ^{183}Au is, so far, the only nucleus in which both the increasing and the decreasing parts are observed and thus gives the experimental evidence of the complete transverse wobbling phenomenon.

The incidence of immunofluorescence patterns and specific autoantibodies observed in autoimmune patients in a tertiary care centre.

Summary: Objectives: Testing for antinuclear antibodies (ANA) facilitates the diagnosis of autoimmune diseases (ADs). Here, we report an incidence of ANA positivity and its patterns by indirect immunofluorescence (IIF) and specific autoantibodies through immunodot assay. Methods: Sera from 993 patients presenting with various ADs were tested by IIF and immunodot assay. Results: ANAs were detected in 39.7%, of which speckled pattern was predominantly observed (50.8%). 56.8% of samples were positive on the immunodot assay with SSA Ro 60 antibody being the most prevalent (30.7%). Discussion: A significant correlation (p minor 0.0001) was observed between patterns and auto-antibodies. Coarse speckled (CS) and homogeneous were overly represented by antibodies SSA Ro 60 (13%) and nucleosomes (5.8%) respectively. Mi-2, PL-7, PL-12, and SP-100 were the rarest autoantibodies specificities found. Conclusions: The presence of a particular IIF pattern is predictive of a specific autoantibody in the sample. Association of IIF patterns and specific autoantibody are relevant for a more accurate diagnosis of disease.

Normal and resonant Auger spectroscopy of isocyanic acid, HNCO.

In this paper, we investigate HNCO by resonant and nonresonant Auger electron spectroscopy at the K-edges of carbon, nitrogen, and oxygen, employing soft X-ray synchrotron radiation. In comparison with the isosteric but linear CO2 molecule, spectra of the bent HNCO molecule are similar but more complex due to its reduced symmetry, wherein the degeneracy of the π-orbitals is lifted. Resonant Auger electron spectra are presented at different photon energies over the first core-excited 1s → 10a' resonance. All Auger electron spectra are assigned based on ab initio configuration interaction computations combined with the one-center approximation for Auger intensities and moment theory to consider vibrational motion. The calculated spectra were scaled by a newly introduced energy scaling factor, and generally, good agreement is found between experiment and theory for normal as well as resonant Auger electron spectra. A comparison of resonant Auger spectra with nonresonant Auger structures shows a slight broadening as well as a shift of the former spectra between -8 and -9 eV due to the spectating electron. Since HNCO is a small molecule and contains the four most abundant atoms of organic molecules, the reported Auger electron decay spectra will provide a benchmark for further theoretical approaches in the computation of core electron spectra.

Molecular cloning and expression of FGF2 gene in pre-implantation developmental stages of in vitro-produced sheep embryos.

Early embryonic mortality is one of the main sources of reproductive loss in domestic ruminants including sheep. Fibroblast growth factor-2 (FGF-2) is a member of FGFs family that mediates trophoblast activities and regulates embryonic development in various species. In this study, we have cloned, characterized sheep FGF2 cDNA (KU316368) and studied the expression in sheep embryos. Ovaries of non-pregnant sheep were collected from local abattoir and matured in culture medium at 38.5ºC, 5% CO2 , 95% humidity for 22-24 hr. The matured oocytes were inseminated with capacitated spermatozoa in Brackett and Oliphant medium and resulted embryos were cultured in CO2 incubator for 6-7 days to complete the developmental stages from two cells to blastocyst stage. Total RNA was extracted from immature oocytes (n = 100), mature oocytes (n = 100) and different stages of embryos such as 2 cell (n = 50), 4 cell (n = 25), 8 cell (n = 12), 16 cell (n = 6), morula (n = 5) and blastocyst (n = 3). The total RNA isolated from the oocytes and embryos was reverse transcribed and subjected to real-time polymerase chain reaction using sequence-specific primers and SYBR green as the DNA dye. On sequence analysis, the nucleotide sequence of sheep FGF2 exhibited highest sequence similarity with cattle (100%) and least with rat and mouse (69.2%). At the deduced amino acid level, a highest degree of similarity was noticed with cattle, buffalo, goat, pig, camel and horse (100%) and lowest degree of identity with rat, human and mouse (98.2%). The FGF2 mRNA expression was higher in immature and mature oocytes and gradually decreases from 2-cell stage of embryo to the blastocyst stage. More over a significant differences in FGF2 mRNA expression (p < .05) were observed between immature oocytes and all pre-implantation stages of embryo. It can be concluded that FGF-2 plays a significant role in pre-implantation and early development of embryos in sheep.

Amelioration of oxidative stress using N-acetylcysteine in canine parvoviral enteritis.

Previously, antioxidants have not been evaluated for treatment of parvoviral diarrhea in dogs. In this study, antioxidant potential of N-acetylcysteine (NAC) in dogs infected with canine parvovirus with a nonblinded randomized clinical trial has been carried out. A total 18 parvo-infected dogs were randomly divided into two groups: nine parvo-infected dogs were treated with supportive treatment and nine parvo-infected dogs were treated with NAC along with supportive treatment. Simultaneously, nine healthy dogs were kept as healthy control. In parvo-infected dogs, marked hemoconcentration, leucopenia, neutropenia and oxidative stress were noticed compared to healthy dogs. The NAC treatment progressively improved the leukocyte, neutrophil, monocyte, and eosinophil counts over the time in parvovirus-infected dogs compared to dogs that received only supportive treatment. In addition, NAC treatment significantly improved glutathione S-transferase (GST) activity and decreased nitrite plus nitrate (NOx) and malondialdehyde (MDA) concentrations on day 3 and 5 compared to supportive treatment in parvo-infected dogs. However, supportive treatment alone failed to ameliorate oxidative stress in the infected dogs till day 5. The results of this study suggest that NAC represents a potential additional treatment option that could be considered to improve the health condition and minimize the duration of hospitalization in case of canine parvoviral diarrhea.

Antisperm antibodies in repeat-breeding cows: Frequency, detection and validation of threshold levels employing sperm immobilization, sperm agglutination and immunoperoxidase assay.

Antisperm antibodies have been found in repeat-breeding(RB) cows, and those causing agglutination and/or immobilization of sperm are considered to be closely related to unexplained infertility. However, a standard protocol for identifying antisperm antibodies (ASA) in cattle is not validated. Therefore, an investigation was undertaken to evaluate sperm immobilization (SIT), sperm agglutination (SAT) and immunoperoxidase (IPT)assays for detection of ASA in serum and their respective threshold levels for confirmation. Animals (heifers, normally breeding, repeat-breeding and pregnant animals) that were free from IBR, brucellosis and uterine infections (screened by clinical examination) were included in the study. Sperm agglutinating, sperm immobilizing and antisperm antibodies evaluated by respective assay were significantly higher (p < .05) in RB cows compared to other groups. The SIT assay was able to identify 61% of RB caused by ASA, more than those employing SAT and IPT. Furthermore, a dilution rate of 1:5 and 1:80 (confirms 59.0 and 57.0% RB+ve)were sufficient to diagnose ASA by SAT and IPT, respectively. Results indicate the presence of __12.6% clumped spermatozoa and __ 2.6%(cut-off value) peroxidase-positive spermatozoa at 1:5 and 1:80 dilutions diagnosed with SAT and IPT, respectively, may be considered as repeaters arising out of ASA. Furthermore, study also showed the presence of lower incidence of ASA positivity in other groups of animals (heifer

Novel identification of Factor XI deficiency in Indian Sahiwal (Bos indicus) cattle.

Factor-XI deficiency (FXID) is inherited as autosomal lethal recessive disorder of carrier Holstein-Friesian bulls. A 76 base pair segment insertion into exon 12 in Factor-XI gene causes FXID in cattle. Keeping this in view the present study was conducted to screen breeding bulls of both indigenous and exotic breeds for mutation in Factor-XI gene and to find out the frequency of FXID carrier animals in breeding bulls. A total of 120 bulls of different age group maintained at Frozen Semen Bull Station, India were randomly selected from different cattle breeds to screen presence of FXID syndrome in breeding sires. Genomic DNA was isolated from blood of the selected bulls. PCR parameters were standardized to obtain 244 and 320 bp amplicons. The results showed that 2 Sahiwal bulls out of 120 animals were carrier for FXID. Amplicons of the carrier animals were sequenced and annoted, which confirms a 76 bp insertion in the exon 12. Bleeding and clotting time showed considerable discrepancy in the carrier animals as compared to the normal animals. The findings of relative mRNA expression of Factor XI transcript revealed identical tendency in the carrier. The frequency of carrier animals and mutant allele was 2.5 % and 0.025 respectively. This study recommends for screening of breeding at AI bull centers in the country for FXID. The study also stands a merit for identification of FXID carrier in Bos indicus for the first time.

Somatic sex identity is cell autonomous in the chicken.

In the mammalian model of sex determination, embryos are considered to be sexually indifferent until the transient action of a sex-determining gene initiates gonadal differentiation. Although this model is thought to apply to all vertebrates, this has yet to be established. Here we have examined three lateral gynandromorph chickens (a rare, naturally occurring phenomenon in which one side of the animal appears male and the other female) to investigate the sex-determining mechanism in birds. These studies demonstrated that gynandromorph birds are genuine male:female chimaeras, and indicated that male and female avian somatic cells may have an inherent sex identity. To test this hypothesis, we transplanted presumptive mesoderm between embryos of reciprocal sexes to generate embryos containing male:female chimaeric gonads. In contrast to the outcome for mammalian mixed-sex chimaeras, in chicken mixed-sex chimaeras the donor cells were excluded from the functional structures of the host gonad. In an example where female tissue was transplanted into a male host, donor cells contributing to the developing testis retained a female identity and expressed a marker of female function. Our study demonstrates that avian somatic cells possess an inherent sex identity and that, in birds, sexual differentiation is substantively cell autonomous.

Effect of ammonia-generating diet on ovine serum and follicular fluid ammonia and urea levels, serum oestrogen and progesterone concentrations and granulosa cell functions.

This study was undertaken to elucidate the effect of ammonia-generating diet on serum and follicular fluid ammonia and urea levels, serum oestrogen and progesterone concentrations and granulosa cell growth and secretion parameters in ewes (Ovis aries). Ewes were fed with 14% CP diet (control) or ammonia-generating diet or ammonia-generating diet plus soluble sugar. The serum and follicular fluid ammonia and urea level, serum oestrogen and progesterone levels and granulosa cell (obtained from ovaries of slaughtered ewes) growth parameters and secretory activities were estimated. Ammonia-generating diet (high-protein diet) increased the serum ammonia and urea concentration. Supplementation of soluble sugar significantly reduced the ammonia concentration in serum with comparable levels as in control group; however, the urea level in the same group was higher than that observed in control group. Supplementation of soluble sugar significantly reduced the follicular fluid ammonia concentration; however, the level was significantly higher compared to control group. Supplementation of soluble sugar brought down the follicular fluid urea level comparable to that observed in control group. Oestrogen and progesterone levels remained unchanged in ewes fed with different types of diet. Oestrogen and progesterone secretion were significantly lowered from granulosa cells recovered from ewes fed with high ammonia-generating diet. Low metabolic activity and high incidence of apoptosis were observed in granulosa cells obtained from ovaries of ewes fed with ammonia-generating diet.

Prevalence and distribution of White Spot Syndrome Virus in cultured shrimp.

White Spot Syndrome Virus (WSSV) is a dsDNA virus causing White Spot Syndrome Disease (WSSD) in shrimp with almost 100% morality rate within 3-10 days. In Bangladesh, WSSD is one of the major impediments of shrimp farming. This study first investigated the prevalence and distribution of WSSV in cultured shrimps of the coastal regions in Bangladesh. A total of 60 shrimp samples, collected from the 25 shrimp farms of different coastal regions (Satkhira, Khulna, Bagerhat and Cox's Bazar), were analysed during 2013-2014 by conventional PCR using VP28 and VP664 gene-specific primers; 39 of 60 samples were found WSSV positive. SYBR green real-time PCR using 71-bp amplicon for VP664 gene correlated well with conventional PCR data. The prevalence rates of WSSV among the collected 60 samples were Satkhira 79%, Khulna 50%, Bagerhat 38% and Cox's Bazar 25%. Sequencing of WSSV-positive PCR amplicons of VP28 showed 99% similarity with WSSV NCBI Ref/Seq Sequences. Molecular analysis of the VP28 gene sequences of WSSV revealed that Bangladeshi strains phylogenetically affiliated to the strains belong to India. This work concluded that WSSV infections are widely distributed in the coastal regions cultured shrimp in Bangladesh.

Size-selective feeding on phytoplankton by two morpho-groups of the small freshwater fish Amblypharyngodon mola.

Two morpho-groups (i.e., small, MGS and big, MGL) of the small freshwater fish Amblypharyngodon mola were studied for their feeding behaviour in the natural environment. Both the morpho-groups fed on a variety of phytoplankton including Cyanophyceae, Chlorophyceae, Bacillariophyceae and Euglenophyceae. The fish had more Chlorophyceae and Bacillariophyceae in their gut than other phytoplankton. Costello's selectivity plots revealed that the MGS fed on the smaller phytoplankters (2-6 µm in size), whereas the MGL fed on both the small and large (up to 12 µm in size) phytoplankters. The differences in mouth areas between the two morpho-groups were explained as a possible reason of size-selective feeding and contribute to overcome gape limitation in A. mola. This is further accompanied by the uniform pore size of the gills (2 µm) in all the morpho-groups. This study concluded that A. mola exhibits a size-dependent feeding strategy regulated by gape limitation at the ingestion level. With ontogenetic shifts, flexibility appears to overcome such a limitation in the MGL, having a wider mouth area supported by jaw opening ability.

Oxygen self-diffusion in HfO2 studied by electron spectroscopy.

High-resolution measurement of the energy of electrons backscattered from oxygen atoms makes it possible to distinguish between (18)O and (16)O isotopes as the energy of elastically scattered electrons depends on the mass of the scattering atom. Here we show that this approach is suitable for measuring oxygen self-diffusion in HfO2 using a Hf(16)O2 (20 nm)/Hf(18)O2 bilayers (60 nm). The mean depth probed (for which the total path length equals the inelastic mean free path) is either 5 or 15 nm in our experiment, depending on the geometry used. Before annealing, the elastic peak from O is thus mainly due to electrons scattered from (16)O in the outer layer, while after annealing the signal from (18)O increases due to diffusion from the underlying Hf(18)O2 layer. For high annealing temperatures the observed interdiffusion is consistent with an activation energy of 1 eV, but at lower temperatures interdiffusion decreases with increasing annealing time. We interpret this to be a consequence of defects, present in the layers early on and enhancing the oxygen diffusivity, disappearing during the annealing process.

Investigation of an outbreak of infectious pustular balanoposthitis in cattle breeding bulls at a frozen semen bank.

Infectious pustular balanoposthitis (IPB) is one of the reproductive disorders caused by bovine herpesvirus 1 (BoHV1) that can be transmitted through artificial insemination. A herd of 63 breeding bulls at a frozen semen bank in Odisha state in India experienced a suspected outbreak of IPB, with 11 bulls showing clinical signs of the infection. Clinical signs were noticed in two bulls initially and a few days after in the other nine animals. Serum samples from 53 bulls were examined for anti-BoHV1 antibodies using a virus neutralisation test (VNT) and a competitive enzyme-linked immunosorbent assay (cELISA); the remaining ten bulls were not included in the study because it was difficult to restrain them at that time. Paired serum samples were collected 21 days apart from ten clinically affected bulls (the eleventh clinically affected bull was not included in the study for the reason stated above). In the neutralisation test, the paired serum samples showed a two- to fourfold increase in anti-BoHV1 antibody titre; in the cELISA, the paired samples were also found positive for anti-BoHV1 antibodies. Serum samples from 43 in-contact bulls were collected about day 22 after the first observation of clinical infection in the herd. Among these serum samples, a total of 30 were found positive for anti-BoHV1 antibodies in the VNT and a total of 30 were found positive in cELISA. Ten samples were positive in one test but not the other and 25 tested positive in both tests. In all, 35 serum samples from in-contact bulls tested positive in either one or both of the two types of test. An overall agreement of 76.74% was found in detection of anti-BoHV1 antibodies in the two tests. Sensitivity was higher than specificity in detection of anti-BoHV1 antibodies in the serum samples. The glycoprotein C region of the genomic DNA of BoHV1 was amplified from semen samples by polymerase chain reaction. The findings from the outbreak indicate that continuous monitoring of breeding bulls at frozen semen banks is warranted to avoid the risks associated with artificial insemination.