Body Water Loss Research Articles

Kids With Altitude: Acute Mountain Sickness and Changes in Body Mass and Total Body Water in Children Travelling to 3800 m.

We explored the incidence of acute mountain sickness (AMS) and extravascular lung water (ELW) in children in relation to changes in body composition and peripheral blood oxygenation (SpO2) during 1 week of acclimatization to 3800 m. In a prospective cohort study, 10 children (7 female, ages 7-14 y) and 10 sex-matched adults (ages 23-44 y) traveled via automobile from sea level to 3000 m for 2 nights, followed by 4 nights at 3800 m. Each morning, body mass and body water (bioelectrical impedance), SpO2 (pulse oximetry), AMS (Lake Louise Questionnaire), and ELW (transthoracic echocardiography) were measured. No differences were found between children and adults in SpO2 or ELW. At 3800 m 7 of 10 children were AMS+ vs 4 of 10 adults. Among those AMS+ at 3800 m, the severity was greater in children compared to adults (5±1 vs 3 ± 0; P=0.005). Loss of body mass occurred more quickly in children (day 5 vs day 7) and to a greater extent (-7±3% vs -2±2%; P<0.001); these changes were mediated via a larger relative loss in total body water in children than in adults (-6±5% vs -2±2%; P=0.027). Children demonstrated a higher incidence of AMS than adults, with greater severity among those AMS+. The loss of body water and body mass at high altitude was also greater in children, albeit unrelated to AMS severity. In addition to awareness of AMS, strategies to maintain body weight and hydration in children traveling to high altitudes should be considered.

Anthropomorphism and Its Adverse Effects on the Distress and Welfare of Companion Animals.

Simple SummaryAnthropomorphism refers to the practices in which humans attribute human emotional and behavioral features to non-human animals and objects. For some people, this represents a means to reinforce the human-animal connection, display empathy towards their companion animals, and show care and interest in their well-being. However, some anthropomorphic behaviors towards pets are often driven by temporary fashions that may have a detrimental effect on animal welfare, both physically (e.g., dermatological, orthopedic, and nutritional diseases) and emotionally (e.g., fear, anxiety, aggressiveness). Not less importantly, in some cases, they may pose a risk for public health (e.g., the transmission of zoonotic diseases). This article focuses on the adverse physiological and behavioral effects that may derive from anthropomorphism in order to understand the magnitude of the repercussions on the welfare of companion animals.Anthropomorphic practices are increasing worldwide. Anthropomorphism is defined as the tendency to attribute human forms, behaviors, and emotions to non-human animals or objects. Anthropomorphism is particularly relevant for companion animals. Some anthropomorphic practices can be beneficial to them, whilst others can be very detrimental. Some anthropomorphic behaviors compromise the welfare and physiology of animals by interfering with thermoregulation, while others can produce dehydration due to the loss of body water, a condition that brings undesirable consequences such as high compensatory blood pressure and heat shock, even death, depending on the intensity and frequency of an animal’s exposure to these stressors. Malnutrition is a factor observed due to consumption of junk food or an imbalance in caloric proportions. This can cause obesity in pets that may have repercussions on their locomotor apparatus. Intense human–animal interaction can also lead to the establishment of attachment that impacts the mental state and behavior of animals, making them prone to develop aggression, fear, or anxiety separation syndrome. Another aspect is applying cosmetics to pets, though scientific studies have not yet determined whether cosmetic products such as coat dyes, nail polish, and lotions are beneficial or harmful for the animals, or to what extent. The cohabitation of animals in people’s homes can also constitute a public health risk due to infectious and zoonotic diseases. In this context, this paper aims to analyze the adverse effects of anthropomorphism on the welfare of companion animals from several angles—physiological, sanitary, and behavioral—based on a discussion of current scientific findings.

The Aphelenchus avenae genome highlights evolutionary adaptation to desiccation

Some organisms can withstand complete body water loss (losing up to 99% of body water) and stay in ametabolic state for decades until rehydration, which is known as anhydrobiosis. Few multicellular eukaryotes on their adult stage can withstand life without water. We still have an incomplete understanding of the mechanism for metazoan survival of anhydrobiosis. Here we report the 255-Mb genome of Aphelenchus avenae, which can endure relative zero humidity for years. Gene duplications arose genome-wide and contributed to the expansion and diversification of 763 kinases, which represents the second largest metazoan kinome to date. Transcriptome analyses of ametabolic state of A. avenae indicate the elevation of ATP level for global recycling of macromolecules and enhancement of autophagy in the early stage of anhydrobiosis. We catalogue 74 species-specific intrinsically disordered proteins, which may facilitate A. avenae to survive through desiccation stress. Our findings refine a molecular basis evolving for survival in extreme water loss and open the way for discovering new anti-desiccation strategies.

Physiological response of weaned piglets to two transport durations observed in a Canadian commercial setting.

Observational studies describing the impact of transport duration on weaned piglet welfare are limited. Current Canadian transport regulations are heavily informed by studies involving market hogs. Due to physiological differences between weaned piglets and market hogs, additional data on their response to transport are needed for age-specific evidence-based recommendations. A cohort study was conducted to describe and compare mortality, injury, weight change, hematological or biochemical changes in hydration, muscle injury and stress response observed in weaned piglets undergoing short duration (SD, <3 h), or long duration (LD, >30 h) commercial summertime transport events. Data collection on 440 of 11,434 transported piglets occurred the morning of the day before transport (T0), at arrival (T1) and approximately 3 to 4 d (78 to 93 h) after arrival at the nursery barn (T2). Low mortality occurred over all transport events (0.06%) with no association observed between transport duration and odds of death during transport (P = 0.62). The incidence of lameness between T0 and T1 was low (1.84% of the 435 focal piglets scored) with all lameness cases identified as mild in severity. Lesions on ears and skin were more prevalent than other injury types after transport (T1) and may have been related to mixing aggression associated with weaning rather than transport alone. LD piglets weighed 0.39 kg less than SD piglets at T1 (P < 0.01), but no difference in group weight was observed at T2 (P = 0.17). Hematological and biochemical differences were present between groups at T1. LD piglets had increased hematocrit levels compared with SD piglets (P = 0.01), suggesting increased body water losses. SD piglets showed greater levels of muscle injury compared with LD piglets including elevated aspartate aminotransferase (P < 0.01) and creatine kinase (P < 0.01). However, these parameters were within normal reference ranges for piglets of this age group. Indicators of physiological stress response including cortisol and neutrophil to lymphocyte ratios were elevated in SD piglets compared with LD piglets (P = 0.02 and P < 0.01, respectively). The results of this study demonstrate that both short and long transport durations can result in detectable physiological changes in weaned piglets. The overall impact of these durations on piglet welfare should be further explored by analyzing behavioral time budgets during and after transport.

Abstract 23: Body Fluid And Sodium Loss Leads To Aldosterone Hypersecretion And Muscle Catabolism In Hepatocellular Carcinoma Rats.

Background: The number of cancer survivors coincides with cardiovascular diseases is increasing, therefore, we are promoting the concept of “Onco-Hypertension” to clarify the mechanism linking cancer and blood pressure. In this study, we evaluated body osmolyte and water imbalance in hepatocellular cancer (HCC) model rats. Methods: Wistar rats were administered diethylnitrosamine (DEN) (1.5 μg/day, p.o.), a carcinogenic drug, for 8 weeks to establish liver cancer. Three weeks after the completion of DEN administration, we investigated blood pressure, tissue osmolyte and water content, and its association with aldosterone secretion. Results: HCC rats significantly reduced blood pressure, skin sodium, potassium, and water content. In the carcass (muscle + bone), dry weight, sodium, potassium, and water content were dramatically reduced without changing bone mass in HCC rats, suggesting that HCC causes muscle wasting to supply osmolyte and water for the dehydrated organs. These osmolytes and water loss were significantly associated with increased urinary aldosterone excretion. Supplementation of 0.25% salt water to drink improved body sodium and water loss and muscle wasting in HCC rats, which were completely suppressed by treatment with spironolactone (75 mg/kg/day, p.o.), a mineralocorticoid receptor (MR) blocker. Conclusion: These findings suggest that HCC causes body osmolyte and water loss, which leads to aldosterone hypersecretion and muscle catabolism to compensate for dehydration. A relatively small amount of salt supplement ameliorates the HCC-induced dehydration and muscle wasting via aldosterone/MR-mediated sodium and water restoration.

Specificity of Meteorological and Biometeorological Conditions in Central Europe in Centre of Urban Areas in June 2019 (Bydgoszcz, Poland)

The work describes diurnal meteorological and biometeorological conditions in June 2019 in the urban areas of Central Europe. UTCI, STI, Oh_H, WL, and OV indices were calculated based on 24-h data from Bydgoszcz (Poland) for hot days. The degree of risk connected with heat stress of different intensities, risk of hyperthermia, body water loss, and decreased oxygen volume was determined. The studies showed that June 2019 was an example of an extreme situation with a heatwave that generated high stress for the inhabitants of urban areas. The conditions were burdensome mostly due to “very strong” and “strong” heat stress and periodic risk of dehydration, situations that could quickly lead to overheating of the body and a decreased oxygen volume leading to stress.

Thermoregulatory Tactics and Water Balance of Centris caesalpiniae Males in Flight

It is advantageous for flying insects to be functional across a range of temperatures when competing for mates; breadth of performance can arise from broad tolerance or thermoregulation. Tactics of flying insects typically include moving hot hemolymph from the thorax to cooler body segments, evaporative water loss, and changes in metabolic heat production. For dimorphic Centris caesalpiniae male bees, the large morphs dig for females at ground-level, flying infrequently, whereas the small morph hovers and flies. At a mate-aggregation site, air temperature varied from 17 ºC to 37 ºC across and within days; operative temperatures of metanders reached 50 ºC on the ground when mating activity ceased, suggesting that high temperatures and radiation constrain the mating period, and that C. caesalpiniae's upper thermal tolerance is high, but not exceptional. These bees exhibited modest thermoregulation of thorax and head temperatures, with segment temperatures increasing 0.5-0.6 ºC per ºC air temperature both on the ground and in flight. During flight, evaporative water loss and heat movement to the abdomen contributed to thermoregulation. On the ground, bees moved hemolymph to the head. These results suggest bees thermoregulate the thorax to improve flight performance. Metabolic water production was about half of water loss rates and metanders lose about 17% of their body water per hour during flight. No one has observed metanders feeding or drinking, and several hours of flight would presumably cause a lethal loss of body water. While we currently lack information on the duration of activity of individuals, it is possible that thermoregulatory water loss may constrain the activity of metanders.

Industrial workwear for hot workplace environments: thermal management attributes.

Personal protective clothing (PPC) is critical for worker safety and wellbeing from both protection and thermal management perspectives, particularly as PPC typically covers more than 90% of the body. Research of PPC in low-risk categories such as mining, oil, gas, and construction and their thermal management attributes is limited, although these industries represent a significant proportion of the industrial workforce, work across a broad range of major industries, and frequently work in hot and/or humid thermal environments. This study evaluated and characterized the thermal management attributes of a selection of commercial low-level risk PPC ensembles currently used around the world as well as a civilian/corporate wear ensemble, using a sweating thermal manikin. The results demonstrate that there are substantially poorer thermal attributes for the PPC ensembles. Predicted Heat Strain Index (PHS) results for hot conditions reveal significantly lower duration limited exposure (DLE) and considerably greater body water loss for the wearers of PPC. Opportunities to substantially reduce PPC material mass and improve construction for these low-level risk categories in order to enhance thermal management performance are identified. Relationships between the thermal attributes of PPC and civilian clothing, and their garment construction, fit, and material characteristics are identified, providing new and important knowledge for current performance and direction for development of new improved PPC. This study provides researchers, developers, and garment designers with valuable insights for future improvement of PPC to create improved PPC for industrial workwear worn in hot environments.

Exercise under heat stress: thermoregulation, hydration, performance implications, and mitigation strategies.

A rise in body core temperature and loss of body water via sweating are natural consequences of prolonged exercise in the heat. This review provides a comprehensive and integrative overview of how the human body responds to exercise under heat stress and the countermeasures that can be adopted to enhance aerobic performance under such environmental conditions. The fundamental concepts and physiological processes associated with thermoregulation and fluid balance are initially described, followed by a summary of methods to determine thermal strain and hydration status. An outline is provided on how exercise-heat stress disrupts these homeostatic processes, leading to hyperthermia, hypohydration, sodium disturbances, and in some cases exertional heat illness. The impact of heat stress on human performance is also examined, including the underlying physiological mechanisms that mediate the impairment of exercise performance. Similarly, the influence of hydration status on performance in the heat and how systemic and peripheral hemodynamic adjustments contribute to fatigue development is elucidated. This review also discusses strategies to mitigate the effects of hyperthermia and hypohydration on exercise performance in the heat by examining the benefits of heat acclimation, cooling strategies, and hyperhydration. Finally, contemporary controversies are summarized and future research directions are provided.

Microbial Assay of the Waterborne Pathogen on Supplied Drinking Water in Gopalganj Area, Bangladesh and its Future Effect

Around 60% of water constitute the human body if about 2% of the body’s water content drop anyone dehydration must have a remarkable effect. Studies show that the loss of body water can break many aspects of brain function. About Eight 8-ounce (237-mL) glasses of water always consult by the physician for a sound person. But unfortunately, If this drinking water becomes impure it affects to develop the various vital dysfunction in our body. Infrequent bowel actions and trouble passing footrest, brain associate dysfunction along with familiar waterborne infections such as looseness, polio, diarrhoea and meningitis are the common conditions that arise for the water-borne pathogen in water. Gopalganj is a town in Gopalgonj District belonging to the Dhaka Division of Bangladesh. According to the census(cf) of 2011-03-15, 53778 individuals are living here from the divergent profession. For geographical reasons the most of the area specially Gopalganj town along with Gobra, Ghonapra, Tungipara where most government institutions are located the groundwater is not suitable for drinking as Iron and Arsenic are the supremacy amount. That’s why this is the common scenery of these areas to use drinking water jar for the purpose of safe water. For this reason here have already found about 10-15 drinking water jar supplier company. In this research, we performed the microbiological assay to observe the presence or absence of water-born pathogen on these drinking water containing the water jar along with the morphological characteristics of these pathogens. In point of fact, we found that there is 3 to 6 type of microbes are present in this water. Among these pathogens, there are the supremacy of gram-positive bacteria than gram-negative bacteria along with some moulds co-exist on these microbiomes.

Electrical Resistance of Stainless Steel/Polyester Blended Knitted Fabrics for Application to Measure Sweat Quantity.

Skin wetness and body water loss are important indexes to reflect the heat strain of the human body. According to ISO 7933 2004, the skin wetness and sweat rate are calculated by the evaporative heat flow and the maximum evaporative heat flow in the skin surface, etc. This work proposes the soft textile-based sensor, which was knitted by stainless steel/polyester blended yarn on the flat knitting machine. It investigated the relationship between electrical resistance in the weft/warp directions and different water absorption ratio (0–70%), different sample size (2 cm × 2 cm, 2 cm × 4 cm, 2 cm × 6 cm and 2 cm × 8 cm). The hydrophilic treatment effectively improved the water absorption ratio increasing from 40% to 70%. The weft and warp direction exhibited different electrical behaviors when under dry and wet conditions. It suggested the weft direction of knitted fabrics was recommended for detecting the electrical resistance due to its stable sensitivity and linearity performance. It could be used as a flexible sensor integrated into a garment for measuring the skin wetness and sweat rate in the future instead of traditional measurements.

Adaptive physiological water conservation explains hypertension and muscle catabolism in experimental chronic renal failure

AimWe have reported earlier that a high salt intake triggered an aestivation‐like natriuretic‐ureotelic body water conservation response that lowered muscle mass and increased blood pressure. Here, we tested the hypothesis that a similar adaptive water conservation response occurs in experimental chronic renal failure.MethodsIn four subsequent experiments in Sprague Dawley rats, we used surgical 5/6 renal mass reduction (5/6 Nx) to induce chronic renal failure. We studied solute and water excretion in 24‐hour metabolic cage experiments, chronic blood pressure by radiotelemetry, chronic metabolic adjustment in liver and skeletal muscle by metabolomics and selected enzyme activity measurements, body Na+, K+ and water by dry ashing, and acute transepidermal water loss in conjunction with skin blood flow and intra‐arterial blood pressure.Results5/6 Nx rats were polyuric, because their kidneys could not sufficiently concentrate the urine. Physiological adaptation to this renal water loss included mobilization of nitrogen and energy from muscle for organic osmolyte production, elevated norepinephrine and copeptin levels with reduced skin blood flow, which by means of compensation reduced their transepidermal water loss. This complex physiologic‐metabolic adjustment across multiple organs allowed the rats to stabilize their body water content despite persisting renal water loss, albeit at the expense of hypertension and catabolic mobilization of muscle protein.ConclusionPhysiological adaptation to body water loss, termed aestivation, is an evolutionary conserved survival strategy and an under‐studied research area in medical physiology, which besides hypertension and muscle mass loss in chronic renal failure may explain many otherwise unexplainable phenomena in medicine.

SEASONAL VARIATIONS IN HAEMATOLOGICAL INDICES IN THE GREY BREASTED GUINEA FOWL (Numida Meleagris Galeata Pallas)

The influence of seasons on the haematological indices were studied in the grey breasted guinea fowl (Numida meleagris galeata pallas) in the arid zone of Borno State. Blood samples for haematological analysis were collected from the wing vein of the birds. The RBC counts and PCV values were significantly (P&lt;0.05) increased during the hot weather period compared to the values obtained in the cold period. This increase may be due to decreased plasma volume resulting from increase in body water loss at high ambient temperatures

Nature Tourism in India-Red Sander Plant Species of YSR District, Andhra Pradesh

The Medical tourism studies report for the year 2015 indicates that more than 2,000,000 patients from abroad travelled to India. Ayurveda has attracted the attention of global population especially the developed countries since ages for the promotion of medical tourism encompassing modern medical sciences and the ancient Indian medical systems Ayurveda, Yoga, Unani, Siddha and Homeopathy (AYUSH). Foreign travellers were coming to India since centuries in search of knowledge. Medical tourism in India is a multibillion-dollar provider industry and attracting millions of foreigners and domestic to visit incredible heritage of country and enjoy the medicinal blessings of traditional Vedas and Upanishads. India is full of well trained, qualified and experienced professionals and doctors. India ‘s medical tourism sector is expected to experience an annual growth rate of 30%, making it Rs. 9,500-crore industry by 2015. Estimates of the value of medical tourism to India go as high as $2 billion a year by 2012. Currently, India is second only to Thailand in the number of medical tourists it has attracted since the early 1990s. Red sandalwood grown on the shale subsoil, at altitudes around 750 meters (2,460 ft), and in semi-arid climatic conditions gives a distinctive wavy grain margin. Lumber pieces with the wavy grain margin are graded as "A" grade. Red sandalwood with wavy grain margins sells at higher prices than the standard wood in market. Red sandalwood is used for treating digestive tract problems, fluid retention, and coughs and for “blood purification.” Red sandalwood might increase the loss of body water through the urine (diuretic effect). Red sanders are used for Cosmetic remedies face pack for dry skin. Many of the Indian hospitals have a holistic center in its premise with more ancient forms of treatments such as yoga and meditation programs, and herbal medicine, naturopathy, homoeopathy, and acupuncture departments.

Molecular Reorganization during the Formation of the Human Skin Barrier Studied In Situ

In vertebrates, skin upholds homeostasis by preventing body water loss. The skin's permeability barrier is located intercellularly in the stratum corneum and consists of stacked lipid lamellae composed of ceramides, cholesterol, and free fatty acids. We have combined cryo-electron microscopy with molecular dynamics modeling and electron microscopy simulation in our analysis of the lamellae's formation, a maturation process beginning in stratum granulosum and ending in stratum corneum. Previously, we have revealed the lipid lamellae's initial- and end-stage molecular organizations. In this study, we reveal two cryo-electron microscopy patterns representing intermediate stages in the lamellae's maturation process: a single-band pattern with 2.0‒2.5 nm periodicity and a two-band pattern with 5.5‒6.0 nm periodicity, which may be derived from lamellar lipid structures with 4.0‒5.0 nm and 5.5‒6.0 nm periodicity, respectively. On the basis of the analysis of the data now available on the four maturation stages identified, we can present a tentative molecular model for the complete skin barrier formation process.

Comprehension of Rukni Amraz (Elemental Diseases) in Perspective of Unani Medicine

According to Unani medicine, arkān are primordial constituents of mawālīd thalātha (three primary matters) i.e. animals, plants and minerals. Therefore, they are responsible for sustenance and growth by providing adequate replenishment to the dissolution occurring in the body. Balance in the proportion of arkān is responsible for healthy state of body and any disturbance in their normal proportion leads to rukni amrāḍ (elemental diseases) e.g. Loss of body water leads to dehydration. One rukn is arḍ along with all its constituents. In arḍi amrāḍ deficiency or excess of any constituent of earth may lead to disturbance in its proportion and can lead arḍi amrāḍ e.g. Deficiency or excess of calcium and iron. This category of disease is mentioned in Unani literature but not described in detail and under the head of elementary diseases. In this paper the hidden aspect of Unani medicine is explored in light of modern knowledge.

Body Water-Mediated Conductivity Actualizes the Insect-Control Functions of Electric Fields in Houseflies.

Simple SummaryThe attractive forces generated in a static electric field, as well as corona and arc discharges generated in a dynamic electric field, are practical approaches for trapping and killing insects that enter the electric field. These electrostatic methods are realized by the conductive nature of the insect body. Thus, this work examined the role of body water on the conduction of electricity in the insect body. Adult houseflies (Musca domestica) were subjected to dehydration, rehydration, refrigeration, and freezing and thawing. These insects were then placed in static and dynamic electric fields to examine whether the release of negative charges from the insect caused attraction in the static field, as well as whether the fly was heated or dismembered when electricity passed through its body in a dynamic field. There was no current in the bodies of dehydrated and frozen flies; hence, there was no attractive force or discharge exposure. In the remaining insects, the results were identical to those in the control insects. Therefore, the conduction of electricity in the insect’s body water enables the insect-control effects of the electric fields.In the present study, the relationship between body water loss and conductivity was examined in adult houseflies (Musca domestica). The events an insect experiences in an electric field are caused by the conductive nature of the insect body (i.e., movement of electricity within or its release from the insect). After houseflies were dehydrated, rehydrated, refrigerated, and frozen and thawed, they were placed in static and dynamic electric fields. Untreated houseflies were deprived of their free electrons to become positively charged and then attracted to the insulated negative pole in the static electric field and were exposed to corona and arc discharge from non-insulated negative pole in the dynamic electric field. There was no current in the bodies of dehydrated and frozen flies; hence, there was no attractive force or discharge exposure. In the remaining insects, the results were identical to those in the untreated control insects. These results indicated that the reduction of body water conductivity inhibited the release of electricity from the body in the static electric field and the discharge-mediated current flow through the body in the dynamic electric field. The insect was affected by the electric fields because of its conductivity mediated by body water.

The Effect of Acute Hypohydration on Indicators of Glycemic Regulation, Appetite, Metabolism and Stress: A Systematic Review and Meta-Analysis.

Evidence synthesizing the effects of acute body water losses on various markers of glycemic regulation, appetite, metabolism, and stress is lacking. Thus, the purpose of this review was to summarize the response of various hormonal changes involved in these physiologic functions to dehydration. A comprehensive literature search for peer-reviewed research in the databases PubMed, Scopus, CINAHL, and SportDiscus was conducted. Studies were included if they contained samples of adults (>18 years) and experimentally induced dehydration as measured by acute body mass loss. Twenty-one articles were eligible for inclusion. Findings suggested cortisol is significantly elevated with hypohydration (standard mean difference [SMD] = 1.12, 95% CI [0.583, 1.67], p < 0.0001). Testosterone was significantly lower in studies where hypohydration was accompanied by caloric restriction (SMD= −1.04, 95% CI [−1.93, −0.14], p = 0.02), however, there were no changes in testosterone in studies examining hypohydration alone (SMD = −0.17, 95% CI [−0.51 0.16], p = 0.30). Insulin and ghrelin were unaffected by acute total body water losses. Acute hypohydration increases markers of catabolism but has a negligible effect on markers of glycemic regulation, appetite, anabolism and stress. Given the brevity of existing research, further research is needed to determine the impact of hydration on glucagon, leptin, peptide YY and the subsequent outcomes relevant to both health and performance.

Lethal and sublethal effect of heat shock on Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae).

Temperature is an important abiotic environmental factor, and is responsible for various kinds of behavioral and physiological changes in living organisms. Induced heat shock is associated with feeding behaviour, reproduction and reactive oxygen species (ROS) generation that causes oxidative damage. In this experiment, we examined the lethal and sublethal effects of heat shock on reproduction, feeding behaviour and antioxidant enzymes, including catalase (CAT), superoxide dismutase (SOD) and peroxidases (POD) in P. solenopsis. Results showed that males were highly susceptible to heat shock treatments than females, as LTemp50 values were 43.8°C for males and 45.11°C for females. Heat shock events non-significantly affected the fecundity in female only treated adults and significantly affected the both sexes heat treated adults, it increased the xylem feeding duration, percentage of xylem feeding adults and reduce the phloem feeding duration and percentage of phloem feeding adults. Similarly it alter the antioxidant enzymes activities, an increase of CAT, SOD and POD activities were noticed in response to highest intensity of heat shock while a reduction of CAT and SOD activity were noticed in response to lowest intensity of heat shock compared to control (30°C). These results suggest that heat shock may result in loss of body water and induce oxidative stress in P. solenopsis. However, antioxidant enzymes play a significant role in overcoming the oxidative damage.

Embryonic stage selection for cryopreservation of the silkworm Bombyx mori and the effects of cryopreservation on embryo tissues

Successful cryopreservation of the important silkworm bioresource, Bombyx mori, is essential. In this study, we aimed for successful cryopreservation using vitrification of silkworm embryos. Furthermore, the embryos were assessed for the most appropriate sampling stage. We found that vitrified embryos developed to the serosa ingestion stage when they were vitrified at embryonic stage 24–25. The most suitable stage for vitrification was around a 5–10 h period when the tracheal fibers were elongating in stage 25. None of the vitrified embryos developed into larvae, although some did develop to the pre-hatching stage. From histological analysis, we found that several small cracks formed on the cuticle covering the hypodermis in the vitrified embryos. Additionally, the midgut epithelium was detached from the midgut wall and mixed with the yolk in the midgut lumen. We speculate that the vitrified embryos died from a rapid loss of body water from the small cracks formed in the cuticle. We also suggest that the vitrified embryos may have resulted in dysfunction of the midgut.