Dead Counts Research Articles

Preliminary Study on Rapid and Simultaneous Detection of Viable Escherichia coli O157:H7, Staphylococcus aureus, and Salmonella by PMA-mPCR in Food.

Escherichia coli O157:H7, Staphylococcus aureus, and Salmonella are major foodborne pathogens that are widespread in nature and responsible for several outbreaks of food safety accidents. Thus, a rapid and practical technique (PMA-mPCR) was developed for the simultaneous detection of viable E. coli O157:H7, S. aureus, and Salmonella in pure culture and in a food matrix. To eliminate false positive results, propidium monoazide (PMA) was applied to selectively suppress the DNA amplification of dead cells. The results showed the optimum concentration of PMA is 5.0 µg/mL. The detection limit of this assay by mPCR was 103 CFU/mL in the culture broth, and by PMA-mPCR was 104 CFU/mL both in pure culture and a food matrix (milk and ground beef). In addition, the detection of mixed viable and dead cells was also explored in this study. The detection sensitivity ratio of viable and dead counts was less than 1:10. Therefore, the PMA-mPCR assay proposed here might provide an efficient detection tool for the simultaneous detection of viable E. coli O157:H7, S. aureus, and Salmonella and also have great potential for the detection and concentration assessment of VBNC cells.

Larvicidal effect of the essential oil of Curcuma xanthorrhiza (ginger java) for Aedes aegypti

The larvicidal effect of the essential oil nanoemulsions of Curcuma xanthorrhiza (known as ginger java) in Aedes aegypti species. For this, they were collected as plants of C. xanthorrhiza Luís, MA and, later, separated as leaves from their respective branches. The essential oil was obtained by means of hydrodistillation by dragging a steam at a temperature of 100ºC for 3 hours. The nanoemulsions were prepared using the phase inversion method. The chemical constituents were quantified and identified by Gas Chromatography Coupled with Mass Spectrometry (GC/MS). Aedes aegypti eggs were transmitted through ovit traps. As Aedes aegypti larvae, they were hatched in mineral water, identified and fed until the 4th instar. For the activity of the activity. living and dead count. A Probit statistical analysis was performed to quantify the Lethal Concentration 50% (LC50). The GC/MS quantified the major components in the essential oil, namely germacrone (25.46%), xanthorrizole (17.52%) and eucalyptol (11.92%). The larvicidal activity of the essential oil nanoemulsion for Aedes aegypti quantified an LC50 of 25.94 mg. L-1, being defined by the evaluation criterion as active in the control and combat of A. aegypti. The essential nanoemulsion of C. xanthorrhiza has efficient larvicidal activity, so there is a need for further studies of its form of operation and safety for the combat and control of Aedes aegypti larvae.

Counting the dead and making the dead count: configuring data and accountability

This article examines the relation between counting, counts and accountability. It does so by comparing the responses of the British government to deaths associated with Covid-19 in 2020 to its responses to deaths associated with the 2003 invasion of Iraq. Similarities and dissimilarities between the cases regarding what counted as data, what data were taken to count, what data counted for, and how data were counted provide the basis for considering how the bounds of democratic accountability are constituted. Based on these two cases, the article sets out the metaphors of leaks and cascades as ways of characterising the data practices whereby counts, counting and accountability get configured. By situating deaths associated with Covid-19 against previous experience with deaths from war, the article also proposes how claims to truth and ignorance might figure in any future official inquiry into the handling of the pandemic.

Establishing a relationship between semen evaluation parameters of freezable and non-freezable Murrah buffalo bull semen

The present study was conducted with an objective of establishing a relationship between semen evaluation parameters of freezable and non-freezable Murrah buffalo semen. Work was conducted at Frozen Semen Bank, RCDF Limited, Bassi, Jaipur, Rajasthan, on 12 apparently healthy pure bred Murrah buffalo breeding bulls. A total of 96 ejaculates (48 each freezable and non-freezable) were analysed at five different stages of processing namely neat semen evaluation, post dilution, post equilibration, post thaw and after 1 h of incubation post-thaw at 37°C for progressive motility, live dead count, reaction to hypo-osmotic solution and acrosomal integrity. Evaluation of the semen was done in two groups, i.e. freezable and non-freezable semen. There was a significant difference in terms of all the semen evaluation parameters between freezable and non-freezable semen at different stages of evaluation. Also, results of the study revealed a highly significant correlation between the various semen evaluation parameters for both the groups.

Live and Dead Bacteria Counts of Different Yogurts Before and After Expiration

Abstract Objectives The objective of this study was to investigate differences in live and dead bacteria counts a month before the expiration date and right after the expiration date and observe any differences in bacteria counts between types of yogurt, brands, and stores tested. Methods Two yogurt containers with the same expiration date were collected for each brand at three stores. The yogurts collected were three national brands of Greek yogurts and five regular yogurts. The first container was tested one month prior to expiry. The second container was tested at the expiration date. After being thoroughly mixed, triplicate 50–75 mg of yogurt were sampled from each carton. Yogurt samples were diluted 9-fold with freshly prepared peptone water. A second dilution was prepared by mixing 25 µL of the yogurt peptone mix with 975 µL of freshly prepared sterile PBS. The samples were incubated for 15 min. at 37°C with 1 µL SYBR green and 5 µL propidium iodine and iced for 1 hour in the dark. 200 µL of dyed yogurt were diluted with 800 µL of PBS and analyzed by flow cytometer (BD Accuri™ C6 Cytometer). Each yogurt sample was run in triplicate on slow speed setting. Flow cytometer parameters were set to differentiate live and dead bacteria based on fluorescence as well as yogurt matrix artifacts. The data was analyzed by a least-squares fit model to test for significance among variables. Results Greek yogurts had significantly higher live and dead bacteria counts compared to regular yogurts. The Greek yogurts differed amongst themselves. Brand 3 had significantly lower live counts than brand 2 and 1. Brand 1 had significantly higher counts of dead bacteria compared to the other two. While differences between Greek yogurt are statistically significant, they are most likely not clinically significant. For the regular yogurt live and dead counts there were no significant differences. No significant differences were observed based on the timing of yogurt sampling or the store the yogurt came from. Conclusions Preparing Greek yogurt involves more straining and whey removal and yields a higher yogurt concentration, so it is no surprise that Greek yogurts have higher bacteria counts. This study demonstrates that when considering yogurt for its probiotic qualities, the most relevant factor is the type of yogurt. Yogurt brand, store, or when it is sampled have little effect on the probiotics count. Funding Sources USU.

Improvement in quality of frozen Jersey bull semen following fortification with chloroquine diphosphate and ascorbic acid

The present study was conducted with an objective of studying the role of certain additives e.g. chloroquine diphosphate and ascorbic acid in maintaining the membrane integrity, viability and motility of spermatozoa at various pre- and post-freezing stages of semen of Jersey bulls maintained under sub-temperate climate. Work was conducted at Sperm Station Palampur, Himachal Pradesh, India, on six apparently healthy pure bred Jersey breeding bulls. A total of 36 ejaculates (6 from each bull), were analysed at six different stages of processing namely neat semen evaluation, post-dilution, post-equilibration, post-thaw and after 1 and 2 h incubation post-thaw at 37°C for progressive motility, live dead count, reaction to hypo-osmotic solution and acrosomal integrity, respectively. Evaluation of the semen was done for three groups, i.e. control group (G1), semen fortified with chloroquine diphosphate (G2) and ascorbic acid (G3).The results of the study revealed a significant improvement in progressive motility, live sperm percentage, reaction to hypo-osmotic solution and acrosomal integrity of semen having chloroquine diphosphate (G2) and ascorbic acid (G3) as additives when compared to control group. So, fortification of semen should be done with chloroquine diphosphate and ascorbic acid to improve the quality of semen in future.

Effect of foot and mouth disease vaccination on seminal traits in pure Holstein Friesian bulls

The present investigation was carried out to study the effect of foot and mouth disease vaccination on seminal traits of 30 Holstein Friesian (HF) bulls, 3-5 years old, maintained at BAIF Central Research Station, Uruli Kanchan, Pune, India. The study period was from August to September 2013 and semen quality traits were evaluated on each bull maintained under identical feeding and management regimes. A total of 180 semen ejaculates were collected with one ejaculate from each bull at 3 days interval in a week at 15 days before, 15 and 30 days after FMD vaccination. Raksha Ovac vaccine of Indian Immunologicals Ltd. was used for vaccination purpose. Seminal traits like fresh and post thaw sperm motility, sperm concentration, semen volume, live and dead count, plasma membrane integrity were evaluated for all the ejaculates. Data on seminal traits were analysed by using one way ANOVA. Results revealed that vaccination had significant (P less than 0.05) effect on post thaw motility and highly significant (P less than 0.01) deleterious effect on HOS test, head and mid piece abnormalities; however no effect was noted on ejaculate volume, sperm concentration, initial motility, viability and tail abnormalities. The observations showed that vaccination alters the seminal traits of pure HF bulls.

Evaluation of subacute bisphenol - A toxicity on male reproductive system.

Aim:The aim was to evaluate the effect of multiple oral administration of bisphenol A (BPA) for 28 days on seminal characteristic on mammal using Wistar rat as a model.Materials and Methods:Rats were randomly divided into five different groups having 6 male rats in each group. The doses chosen were 50, 200, and 600 mg/kg body weight for Groups III, IV and V, respectively, based on preliminary dose range finding study and Group II served as vehicle control and Group I was negative control.Results:Reproductive study in the BPA-treated rats on day 28 revealed that there was significant (p≤0.05) reduction in the epididymal sperm count of rats of Group IV and significant (p≤0.01) decrease in Group V. Sperm motility percentage, dead count percentage, head and tail abnormality percentage were found to be significantly (p≤0.01) increased in rats of BPA-treated groups as compared to rats of control groups. Testes showed necrosis of germinal layer and spermatogonial cells in the seminiferous tubules. Hematological examination revealed significant (p≤0.01) decrease in the mean values of total erythrocyte count (TEC), total leukocyte count (TLC), hemoglobin, packed cell volume, and there was also significant (p≤0.05) lymphocytopenia in treated animals.Conclusion:It can be concluded from this study that subacute toxicity of BPA caused a reduction in the epididymal sperm count, sperm motility, dead count, head and tail abnormality, as well as hematological indices such as TLC, TEC etc. Hence, it appears that BPA affects the germ cells leading to impairment in the spermatogenesis, and thus having its property as reproductive toxicant and it also suppresses bone marrow functioning, which leads to normocytic hypochromic anemia in rats.

Effects of dietary supplementation of organic chromium (picolinate) on physical and biochemical characteristics of semen and carcass traits of male turkeys

This experiment investigated the effect of dietary chromium (Cr as picolinate) on physical and biochemical characteristics of semen and carcass traits of adult male turkey.Seventy-two (72) male turkeys (16 weeks old) were randomly distributed into four dietary treatment groups (4×3×6) for a period of 24 weeks. Three experimental diets were supplemented with 250, 500 and 750μg Cr/kg (T2, T3 and T4 respectively) in basal diet (T1 considered as control).Semen physical characteristics viz. sperm concentration, progressive motility, live and dead count of spermatozoa and fertility differed significantly (P<0.05). Sperm concentration, progressive motility and fertility were higher and dead count was lower in T4 (750μg) group than control (T1) or other dietary treatments (T2 or T3) group. Semen biochemical parameters like creatinine, acid phosphatase (ACP) and alkaline phosphatase (ALP) concentration did not differ significantly among the dietary treatment groups, whereas, total protein, glucose, malondialdehyde (MAD) and cholesterol concentration differed significantly (P<0.05) amongst the treatment groups. Protein and MAD were higher while glucose and cholesterol concentrations were lower in T3 and T4 group than control or T1 group. The shrinkage loss, eviscerated yield, relative weight (as percent of body weight) of breast, thigh and liver improved on supplementation of Cr leading to significantly higher in T4 group in comparison to control.From this study, it could be concluded that supplementation of chromium as chromium picolinate, at 750μg/kg level in diet was beneficial for improving physical characteristics of semen, carcass yield and breast yield of adult male turkeys. However, Cr levels of 500 or 750μg/kg in diet were beneficial for semen biochemical parameters of adult male turkeys.

Polymorphism of growth hormone gene and its association with seminal and sexual behavioral traits in crossbred cattle

The decline in the male reproductive ability in terms of sexual behavior and seminal traits might lead to nonavailability of required number of bulls in a progeny testing program. The present study was conducted in 493 crossbred cattle (Bos taurus × Bos indicus) bulls to study polymorphisms of growth hormone (GH) gene and its association with seminal and sexual behavioral characteristics. A 428-base pair fragment of GH gene spanning over the fourth exon, fourth intron, and fifth exon was amplified and digested with AluI restriction enzyme. Bulls were found to be polymorphic, with two variants, LL and LV, and higher genotypic frequency for LL being 0.88. Twelve nucleotide changes and a single nonsynonymous substitution of Leucine by Valine were observed from GH1 (L) to GH2 (V). Statistical analysis revealed that the genotype of the GH gene had a significant effect on libido score, reaction time, Flehmen response, requirement of mounting stimulus, sperm mass activity, number of semen doses per collection, individual fresh sperm motility, postthaw sperm motility, acrosome integrity, hypo-osmotic swelling test, live and dead count, total morphological abnormality, and head abnormality of sperm in crossbred bulls. Growth hormone gene might be considered a candidate gene for seminal and sexual behavioral traits in crossbred cattle.

Inter relationship between some routine semen evaluation parameters in Jersey X local hill cattle crossbred bulls

The present study was conducted with an objective of establishing a relationship between various routine semen evaluation parameters. Work was conducted at Sperm Station Palampur, Himachal Pradesh, on the semen from five Jersey X local hill cattle crossbred breeding bulls. A total of 40 ejaculates (8 from each bull), were analysed at five different stages of processing namely post dilution, post equilibration, post thaw and after 1 and 2 hours incubation post thaw at 37°C for progressive motility, live dead count, reaction to hypo-osmotic solution, acrosomal integrity and gross morphological abnormalities. The results of the study revealed a highly significant (P&lt;0.01) correlation between the various semen evaluation parameters except for the gross morphological abnormalities where there was a significant (P&lt;0.05) negative correlation between the acrosomal integrity and gross morphological abnormalities.

Performance of Three Alternative Estimators of Stream Residence Time Based on Live and Dead Counts of Salmonids

AbstractData from live and dead fish counts at salmonid spawning areas have been used for decades to estimate stream residence time. Simulation studies indicate that the peak‐to‐peak and median‐to‐median estimates of stream residence time will have at least a 50% negative bias under the best of circumstances. A new estimation technique called the “expectation‐to‐expectation” method is shown to be approximately unbiased over a range of arrival and lifetime distributions. The method also allows corrections for incomplete detection probabilities and carcass retention rates less than 1.0. An important byproduct of the approach is a concurrent estimate of total escapement.

Impact of interrelated and interdependent ecological controls on benthic foraminifera: an example from the Gulf of Guinea

Living and dead benthic foraminiferal assemblages from two size fractions, 63–250 μm and >250 μm, were studied at 128 stations from the shelves down to abyssal plains of the Gulf of Guinea in the eastern equatorial Atlantic. The sample size ranged between 300 and 400 cm 2 of the sediment/water interface, with a penetration depth of 1 cm. Environmental parameters were quantified for sediment composition, food webs, bottom-water oxygen concentrations, and benthic oxygen respiration. Seven major station groupings (named G1–G7) are subdivided by factor analysis. The three most abundant species therein are discussed with respect to their ecological requirements, for both size classes and for living and dead counts. For 49 living species, the range of environmental gradients is established, and for five species live observations are reported. Five station groupings can be attributed toward stepwise ranges scaled by bathymetry and flux rates of organic carbon (G4, 27–75 m; G5, 68–269 m; G6, 250–740 m; G2, 674–2007 m; G1, 1475–4970 m). Two geographically restricted station groupings locally interfinger with other groupings in the upper bathyal and abyssal water depths (G7, 82–451 m; G3, 1002–4658 m). G7 shows lowered oxygen concentrations and benthic oxygen respirations, whereas hemipelagic sediments are typical of G3. The interfingering of G7 and G3, however, is not purely a result of the increasing number of species most perfectly adapted to these environments but rather that these groupings are structured by the decrease of species with lower tolerance towards environmental perturbation. In fact, the more common species have an environmental range much broader than the environmental frame of the groupings they dominate. This observation holds for all size classes and for live and dead counts. We conclude that species-specific preferences and thresholds provide a more valuable and more consistent tool in environmental research than the environmental ranges observed for assemblages.