Maintenance of Simulium Wilhelmia lineatum Meigen and Simulium erythrocephalum de Geer through successive generations in the laboratory

1984 ◽  
Vol 62 (5) ◽  
pp. 870-877 ◽  
Author(s):  
P. J. Ham ◽  
A. E. Bianco
Keyword(s):  
Egg Production ◽  
Blood Feeding ◽  
Water Systems ◽  
Feeding Rates ◽  
Fertility Rates ◽  
Bovine Blood ◽  
Circulating Water ◽  
Development Period ◽  
Successive Generations ◽  
Egg Fertility

With the use of circulating water systems to rear larvae, Simulium erythrocephalum and S. lineatum have been continuously maintained through to the F7 and F3 generations, respectively. Insemination rates of 100% were obtained for both species by the F2 generation. Using chick skin membranes and bovine blood, mean blood-feeding rates of 56 and 87% were achieved for S. lineatum and S. erythrocephalum, respectively. Mean egg production and egg fertility rates increased after the parental generation was produced. Mating trials were peformed to assess conditions for optimum insemination rates. A significant correlation between temperature and complete generation development period was observed.

ПРЕРЫВИСТОЕ ОСВЕЩЕНИЕ ПОВЫШАЕТ ЭФФЕКТИВНОСТЬ ИСКУССТВЕННОГО ОСЕМЕНЕНИЯ КУР В КЛЕТКАХ

2019 ◽  
Keyword(s):  
Reproductive Performance ◽  
Artificial Insemination ◽  
Egg Production ◽  
Laying Hens ◽  
Electric Energy ◽  
Productive Performance ◽  
Feed Conversion ◽  
Scientific Center ◽  
Academy Of Sciences ◽  
Egg Fertility

Intermittent Lighting Improves the Efficiency of Artificial Insemination in Cage Housed Laying Hens Kavtarashvili A.Sh., Kolokolnikova T.N. Federal Scientific Center “All-Russian Research and Technological Poultry Institute” of Russian Academy of Sciences Omsk Agrarian Scientific Center Summary: The effects of different lighting regimes on the oviposition schedule, productive performance, and reproductive efficiency in cage housed laying hens of layer parental flock (Hisex White-R) were studied; the reasonable regime of artificial insemination (AI) under intermittent lighting is proposed. It was found that intermittent lighting regime 1L:4D:4L:1D:4L:10D compared to the constant lighting significantly alters oviposition schedule: under this regime 82.3% of all daily eggs were laid until 9 am (vs. 66.6% in control). This regime and AI at 10 am improved the productive and reproductive performance compared to control (constant lighting 16L:8D and AI at 12 am): mortality by 1.9%, egg production per initial hen by 3.8%, egg weight by 1.1%, percentage of eggs suitable for incubation by 1.9%, egg fertility by 0.9%, hatchability by 2.3%, hatch of chicks by 2.9%, feed conversion ratio (kg of feed per 10 eggs) by 5.3%, the expenses of electric energy for lighting (per 1000 eggs suitable for incubation) by 54.5%. Key words: INTERMITTENT LIGHTING, CAGE HOUSED LAYERS, ARTIFICIAL INSEMINATION (AI), OVIPOSITION SCHEDULE, AI TIMING, PRODUCTIVE PERFORMANCE, REPRODUCTIVE PERFORMANCE

scholarly journals Overexpression of Activated AMPK in the Anopheles stephensi Midgut Impacts Mosquito Metabolism, Reproduction and Plasmodium Resistance

Genes ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 119
Author(s):  
Chioma Oringanje ◽  
Lillian R. Delacruz ◽  
Yunan Han ◽  
Shirley Luckhart ◽  
Michael A. Riehle
Keyword(s):  
Egg Production ◽  
Anopheles Stephensi ◽  
Mitochondrial Dynamics ◽  
Adult Life ◽  
Blood Feeding ◽  
Pathogen Resistance ◽  
Α Subunit ◽  
Significant Difference ◽  
Transgenic Lines ◽  
Ampk Activity

Mitochondrial integrity and homeostasis in the midgut are key factors controlling mosquito fitness and anti-pathogen resistance. Targeting genes that regulate mitochondrial dynamics represents a potential strategy for limiting mosquito-borne diseases. AMP-activated protein kinase (AMPK) is a key cellular energy sensor found in nearly all eukaryotic cells. When activated, AMPK inhibits anabolic pathways that consume ATP and activates catabolic processes that synthesize ATP. In this study, we overexpressed a truncated and constitutively active α-subunit of AMPK under the control of the midgut-specific carboxypeptidase promotor in the midgut of female Anopheles stephensi. As expected, AMPK overexpression in homozygous transgenic mosquitoes was associated with changes in nutrient storage and metabolism, decreasing glycogen levels at 24 h post-blood feeding when transgene expression was maximal, and concurrently increasing circulating trehalose at the same time point. When transgenic lines were challenged with Plasmodium falciparum, we observed a significant decrease in the prevalence and intensity of infection relative to wild type controls. Surprisingly, we did not observe a significant difference in the survival of adult mosquitoes fed either sugar only or both sugar and bloodmeals throughout adult life. This may be due to the limited period that the transgene was activated before homeostasis was restored. However, we did observe a significant decrease in egg production, suggesting that manipulation of AMPK activity in the mosquito midgut resulted in the re-allocation of resources away from egg production. In summary, this work identifies midgut AMPK activity as an important regulator of metabolism, reproduction, and innate immunity in An. stephensi, a highly invasive and important malaria vector species.

scholarly journals Effect of Exogenous Enzymes on Egg Fertility Traits, Egg Production and Oviduct Micro-structure of Layer Birds

2021 ◽  
Vol 3 (1) ◽  
pp. 91-106
Author(s):  
I. C. Chibuogwu
Keyword(s):  
Feed Intake ◽  
Egg Production ◽  
Control Diet ◽  
Diet Group ◽  
Micro Structure ◽  
Exogenous Enzyme ◽  
Feed Cost ◽  
Exogenous Enzymes ◽  
Fertility Traits ◽  
Egg Fertility

The effect of two classes of exogenous enzymes on the egg fertility traits, egg production efficiency and oviduct micro-structure of laying hens was evaluated. Forty-five laying hens (30-weeks old, 1.32-1.40 kg) were randomly allotted into three dietary treatments with fifteen birds per treatment (five birds each in three replicates per treatment) in a completely randomized design. Diet one served as the control diet. Diet two (FS diet) contained a nutrient-targeted exogenous enzyme preparation (Fullzyme®) at 200 g/ton, while diet three (DS diet) contained a mycotoxin-targeted exogenous enzyme preparation (Detoxizyme®) at 500 g/ton. Data on fertility traits (egg volume, length and breadth, weight, yolk diameter, albumen height, air cell, shell thickness, Haugh’s unit, and egg-lay), and egg production (feed intake, egg lay, egg lay efficiency, and feed cost per egg laid) were collected for 42 days. At the end of the experiment, three randomly selected birds per group were euthanized, and their oviducts were harvested and processed for histopathology. Hens fed enzyme supplemented diets had significantly (p < 0.05) better egg fertility traits. Feed intake in the control group did not vary (p > 0.05)from feed intake in the DS or FS group. However, feed cost per egg laid and egg-lay efficiency was higher in the control diet group than in the FS group or DS diet group. No pathologies were observed in the oviduct of birds fed enzymes supplemented or control diet. Exogenous enzymes in diet improved egg fertility traits and production without altering the oviduct micro-structure of Layer hens.

Effect of heat flushing on the concentrations of Legionella pneumophila and other heterotrophic microbes in hot water systems of apartment buildings

1996 ◽  
Vol 42 (8) ◽  
pp. 811-818 ◽  
Author(s):  
Outi M. Zacheus ◽  
Pertti J. Martikainen
Keyword(s):  
Water Temperature ◽  
Legionella Pneumophila ◽  
Heterotrophic Bacteria ◽  
Water System ◽  
Water Systems ◽  
Hot Water ◽  
Circulating Water ◽  
Heterotrophic Microbes ◽  
Before And After ◽  
Circulating Water System

The decontamination of Legionella pneumophila and other heterotrophic microbes by heat flushing in four legionellae-positive hot water systems was studied. Before the decontamination procedure, the concentration of legionellae varied from 3.0 × 10−3 to 3.5 × 10−5 cfu/L and the hot water temperature from 43.6 to 51.5 °C. During the contamination the temperature was raised to 60–70 °C. All taps and showers were cleaned from sediments and flushed with hot water twice a day for several minutes. The decontamination lasted for 2–4 weeks. In a few weeks the heat-flushing method reduced the concentration of legionellae below the detection limit (50 cfu/L) in the hot circulating water system just before and after the heat exchanger. The high hot water temperature also decreased the viable counts of heterotrophic bacteria, fungi, and total microbial cells determined by the epifluorescent microscopy. However, the eradication of legionellae failed in a water system where the water temperature remained below 60 °C in some parts of the system. After the decontamination, the temperature of hot water was lowered to 55 °C. Thereafter, all the studied hot water systems were recolonized by legionellae within a few months, showing that the decontamination by heat flushing was temporary. Also, the contamination of other bacteria increased in a few months to the level before decontamination.Key words: legionellae, hot water system, decontamination, water temperature, heterotrophic bacteria.

scholarly journals 20-Hydroxyecdysone Primes Innate Immune Responses That Limit Bacterial and Malarial Parasite Survival in Anopheles gambiae

mSphere ◽  
2020 ◽  
Vol 5 (2) ◽  
Author(s):  
Rebekah A. Reynolds ◽  
Hyeogsun Kwon ◽  
Ryan C. Smith
Keyword(s):  
Immune Function ◽  
Anopheles Gambiae ◽  
Blood Meal ◽  
Egg Production ◽  
Blood Feeding ◽  
Innate Immune ◽  
Content Type ◽  
Innate Immune Function ◽  
Cellular Immune Function ◽  
Cellular Immune

ABSTRACT Blood feeding is an integral behavior of mosquitoes to acquire nutritional resources needed for reproduction. This requirement also enables mosquitoes to serve as efficient vectors to acquire and potentially transmit a multitude of mosquito-borne diseases, most notably malaria. Recent studies suggest that mosquito immunity is stimulated following a blood meal, independent of infection status. Since blood feeding promotes production of the hormone 20-hydroxyecdysone (20E), we hypothesized that 20E plays an important role in priming the immune response for pathogen challenge. Here, we examine the immunological effects of priming Anopheles gambiae with 20E prior to pathogen infection, demonstrating a significant reduction in bacteria and Plasmodium berghei survival in the mosquito host. Transcriptome sequencing (RNA-seq) analysis following 20E treatment identifies several known 20E-regulated genes, as well as several immune genes with previously reported function in antipathogen defense. Together, these data demonstrate that 20E influences cellular immune function and antipathogen immunity following mosquito blood feeding, arguing the importance of hormones in the regulation of mosquito innate immune function. IMPORTANCE Blood feeding is required to provide nutrients for mosquito egg production and serves as a mechanism to acquire and transmit pathogens. Shortly after a blood meal is taken, there is a peak in the production of 20-hydroxyecdysone (20E), a mosquito hormone that initiates physiological changes, including yolk protein production and mating refractoriness. Here, we examine additional roles of 20E in the regulation of mosquito immunity, demonstrating that priming the immune system with 20E increases mosquito resistance to pathogens. We identify differentially expressed genes in response to 20E treatment, including several involved in innate immune function as well as lipid metabolism and transport. Together, these data argue that 20E stimulates mosquito cellular immune function and innate immunity shortly after blood feeding.

scholarly journals Sexual conflict drives male manipulation of female postmating responses inDrosophila melanogaster

2019 ◽  
Vol 116 (17) ◽  
pp. 8437-8444 ◽  
Author(s):  
Brian Hollis ◽  
Mareike Koppik ◽  
Kristina U. Wensing ◽  
Hanna Ruhmann ◽  
Eléonore Genzoni ◽  
...  
Keyword(s):  
Sexual Conflict ◽  
Egg Production ◽  
Seminal Fluid ◽  
Activity Levels ◽  
Feeding Rates ◽  
Single Male ◽  
Seminal Fluid Proteins ◽  
Expression Of Genes ◽  
Genes Encoding ◽  
And Behavior

In many animals, females respond to mating with changes in physiology and behavior that are triggered by molecules transferred by males during mating. InDrosophila melanogaster, proteins in the seminal fluid are responsible for important female postmating responses, including temporal changes in egg production, elevated feeding rates and activity levels, reduced sexual receptivity, and activation of the immune system. It is unclear to what extent these changes are mutually beneficial to females and males or instead represent male manipulation. Here we use an experimental evolution approach in which females are randomly paired with a single male each generation, eliminating any opportunity for competition for mates or mate choice and thereby aligning the evolutionary interests of the sexes. After >150 generations of evolution, males from monogamous populations elicited a weaker postmating stimulation of egg production and activity than males from control populations that evolved with a polygamous mating system. Males from monogamous populations did not differ from males from polygamous populations in their ability to induce refractoriness to remating in females, but they were inferior to polygamous males in sperm competition. Mating-responsive genes in both the female abdomen and head showed a dampened response to mating with males from monogamous populations. Males from monogamous populations also exhibited lower expression of genes encoding seminal fluid proteins, which mediate the female response to mating. Together, these results demonstrate that the female postmating response, and the male molecules involved in eliciting this response, are shaped by ongoing sexual conflict.

Adverse effects of 15 ppm of p,p′-DDT on three generations of Japanese quail

1973 ◽  
Vol 51 (12) ◽  
pp. 1307-1312 ◽  
Author(s):  
J. S. Carnio ◽  
D. J. McQueen
Keyword(s):  
Adverse Effects ◽  
Japanese Quail ◽  
Egg Production ◽  
Third Generation ◽  
Coturnix Coturnix ◽  
Three Generations ◽  
Egg Fertility

This study deals with the effects of administering 15 ppm of p,p′-DDT in the diet of Japanese quail (Coturnix coturnix) over three generations. Four parameters were measured: (1) egg production, (2) egg fertility, (3) number of abnormal eggs produced, and (4) egg residue concentrations. A comparison of first- and third-generation data shows that egg production decreased slightly, fertility and percentage fertility decreased substantially, the production of abnormal eggs increased, and residue concentrations in the eggs increased. The study suggests that the duration of exposure may be as important as the concentration of DDT administered.

scholarly journals The Effect of Crowding Upon the Oviposition of Grain-Infesting Insects

1942 ◽  
Vol 19 (3) ◽  
pp. 311-340
Author(s):  
A. C. CROMBIE
Keyword(s):  
Conditioned Medium ◽  
Egg Production ◽  
Mutual Effect ◽  
Conditioned Media ◽  
Depressing Effect ◽  
Experimental Conditions ◽  
Oviposition Sites ◽  
Complete Starvation ◽  
Egg Fertility

The crowding of adults invariably had a depressing effect upon the rate of oviposition in the insects studied here, while egg-fertility was not affected. In unconditioned media, at densities possible in actual populations, the reduction of fecundity was, it appears, entirely a result of competition for the oviposition sites usually for two purposes, viz. oviposition and feeding. That is to say, at such densities the effect of crowding upon oviposition was of a behaviouristic nature. When two species were living in the same environment their mutual effect upon each other's fecundity was more or less dependent upon the degree of identity of the niches for which they were competing. The reduction of fecundity of Rhizopertha by homotypically and heterotypically conditioned media was at first roughly proportional to the degree of conditioning, but after a time the effect of all media was the same. Homo- and hetero-typical conditioning were not radically different in effect. It is believed that conditioned medium operates upon fecundity through ‘poisoning’, and that the effect is upon oviposition rather than, as that of starvation, upon egg-production. When returned to an optimum environment the insects recovered from all the experimental conditions mentioned here: immediately from conditions of overcrowding, more slowly from conditioned media, and more slowly still from complete starvation.

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