scholarly journals Evidence against Hormonal Control of Integumentary Water Loss in Periplaneta Americana

1986 ◽  
Vol 121 (1) ◽  
pp. 339-348
Author(s):  
J. MACHIN ◽  
M. J. O'DONNELL ◽  
P. KESTLER
Keyword(s):  
Water Content ◽  
Adult Male ◽  
Water Loss ◽  
Periplaneta Americana ◽  
Hormonal Control ◽  
Differential Effects ◽  
Weight Losses ◽  
Significant Difference ◽  
Hormonal Modulation ◽  
Rate Of Decline

The effect of decapitation on water loss from adult male cockroaches was studied in order to re-examine the possibility of hormonal modulation of integumental permeability. We found no effect of decapitation on the permeability or water content in measurements made on the pronotum. Although overall weight losses of the decapitated animals always exceeded those of intact animals, loss rates and their rate of decline depended on the apparent severity of handling. There was a small but significant difference between the controls and all decapitated and sham-operated animals, and this difference persisted for at least 96 h. We attribute these results principally to the differential effects of cuticle damage, though increased respiratory water loss may also be a factor. Our results draw attention to the complex practical problems involved in obtaining accurate, representative cuticle permeabilities for Periplaneta, and form a basis for questioning the notion of inhibition of cuticular water loss by hormones from the head.

Effect of Dehydration and Rehydration on the Water Content and Na+ and K+ Balance in Adult Male Periplaneta Americana

1977 ◽  
Vol 71 (1) ◽  
pp. 49-66
Author(s):  
LOIS E. TUCKER
Keyword(s):  
Water Content ◽  
Adult Male ◽  
Periplaneta Americana ◽  
Fat Body ◽  
Live Weight ◽  
Ion Content ◽  
Food Reserves

Changes in live weight and in the water, Na+ and K+ content of the tissues and faeces have been examined in adult male Periplaneta americana in various states of hydration. During dehydration the haemolymph volume decreases markedly, but the Na+ and K+ concentrations rise only slightly. Less than 25% of the Na+ removed from the haemolymph during dehydration was found to be excreted, but the K+ excreted during dehydration was in excess of that removed from the haemolymph alone. It seems likely that the major tissue for regulating the haemolymph Na+ during dehydration and rehydration is the fat body, in which dehydration causes an increase, and rehydration a decrease, in the Na:K ratio. The Na+ and K+ content of the fat body was found to be variable in both hydrated and dehydrated animals and absolute changes in the ion content of the tissue could not be estimated because of unknown changes in the amount of food reserves and excretory products.

Effects of Desiccation, Water-Stress and Decapitation on Integumentary Water Loss in the Cockroach, Periplaneta Americana

1987 ◽  
Vol 131 (1) ◽  
pp. 289-300 ◽  
Author(s):  
JOHN NOBLE-NESBITT ◽  
MARWAN AL-SHUKUR
Keyword(s):  
Water Stress ◽  
Water Content ◽  
Water Loss ◽  
Physiological Response ◽  
Initial Phase ◽  
Periplaneta Americana ◽  
Initial Rate ◽  
College Of Education ◽  
Culture Conditions ◽  
The Body

Cockroaches decapitated in a fully hydrated state at first lose water under desiccation much more rapidly than their intact counterparts. The rate of loss decreases with time of desiccation; this decrease is more marked in decapitated than in intact cockroaches. The initial rate of water loss is lower and less variable in predesiccated cockroaches and continues to fall gradually during further desiccation. Decapitation of predesiccated cockroaches has little effect on the rate of water loss. Similarly, the rate of water loss is low with low variability in water-stressed cockroaches taken from dry culture conditions, and decapitation has no significant effect. The lowering of the rate of water loss is not a simple response to lowering of the body water content, but is a two-stage, time-related physiological response of acclimatization to water-stress or desiccation. The initial phase of rapid response requires the presence of the head, whereas the subsequent gradual phase does not. With the techniques used in this investigation, handling-related effects of the decapitation procedure are not significant. Note: Present address: Department of Biology, College of Education, University of Baghdad, Iraq.

Regulation of Transpiration in the Clover Mite Bryobia Praetiosa Koch (Acarina: Tetranychidae)

1965 ◽  
Vol 43 (2) ◽  
pp. 257-269
Author(s):  
PAUL W. WINSTON ◽  
V. EUGENE NELSON
Keyword(s):  
Weight Loss ◽  
Water Content ◽  
Water Loss ◽  
Dry Weight ◽  
Total Weight ◽  
Total Weight Loss ◽  
Weight Losses ◽  
Before And After ◽  
The Face ◽  
Humidity Range

1. Groups of sixteen mites were starved for 48 hr. at 29% R.H. and then exposed for 18 or 24 hr. to one of nine humidities, from 0% to 93% R.H. They were weighed as groups before and after the treatments to determine total weight loss. Dry weights were also obtained to find water content and for the calculation of water and dry-weight losses. All work was done at 25° C. 2. Water loss, considered equivalent to total weight loss, was also obtained under several other conditions; and at all humidities it was found to be highest in mites killed in chloroform vapour while it was considerably less in those killed in HCN gas. Mites with spiracles kept open by air with 10% CO2 lost weight at rates midway between those for dead and those for living animals. 3. There is apparent regulation of body-water content as a percentage of the final weight over the whole humidity range. 4. Water loss is restricted by a CO2-sensitive mechanism, presumably the spiracles. 5. Active regulation of water loss by a cuticular mechanim was shown between 53% and 85% R.H., while at humidities below this, loss was actively restricted but not regulated. 6. It is postulated that both restriction and regulation are brought about by the same mechanism, which might be a form of active transport. 7. Uptake of water from unsaturated air was not found with any of the methods used. 8. Regulation such as was found here would help to maintain the internal environment of these mites as nearly constant as possible in the face of fluctuating humidities.

Delaying Riesling grape berry ripening with a synthetic auxin affects malic acid metabolism and sugar accumulation, and alters wine sensory characters

2012 ◽  
Vol 39 (9) ◽  
pp. 745 ◽  
Author(s):  
Christine Böttcher ◽  
Paul K. Boss ◽  
Christopher Davies
Keyword(s):  
Malic Acid ◽  
Grape Berry ◽  
Hormonal Control ◽  
Sugar Accumulation ◽  
Vitis Vinifera L ◽  
Naphthaleneacetic Acid ◽  
Synthetic Auxin ◽  
Significant Difference ◽  
Berry Ripening ◽  
Rate Of Decline

An improved understanding of the hormonal control of grape (Vitis vinifera L.) berry ripening and the ability to manipulate it are of interest scientifically and commercially. Grapes are nonclimacteric fruit with ethylene unlikely to have a principal role in berry ripening but there are several other hormones thought to be involved. In this work, a significant delay in Riesling berry ripening was achieved through preripening treatments with the synthetic auxin 1-naphthaleneacetic acid (NAA). The initiation of sugar accumulation was delayed and the rate of sugar accumulation was lower in NAA-treated fruit, resulting in a 15-day delay in harvest. NAA treatments also reduced the rate of decline in malic acid levels that occurs during ripening, and increased the synchronicity of malic acid and berry sugar accumulation. Sensory panel assessment revealed a significant difference between wine made from control and NAA-treated fruit. Analysis of the volatile composition of the wines’ headspace showed that the concentration of several compounds was altered significantly by the NAA treatment. These data provide further support for the involvement of auxins in inhibiting ripening and suggest that auxin treatments may be useful in controlling both winery intake, and fruit and wine composition.

Hormonal control of integumentary water-loss: evidence for a novel neuroendocrine system in an insect (Periplaneta americana)

1975 ◽  
Vol 63 (1) ◽  
pp. 143-159
Author(s):  
J. E. Treherne ◽  
P. G. Willmer
Keyword(s):  
Water Loss ◽  
Periplaneta Americana ◽  
Hormonal Control ◽  
Neuroendocrine System ◽  
Corpus Cardiacum ◽  
The Brain

An accelerated water-loss was observed in decapitated individuals, no equivalent increase being obtained following severance of the nervous connectives in the neck. Injection of brain and, to a lesser extent, corpus cardiacum extract resulted in a significant reduction in the rate of loss of water from decapitated individuals. The accelerated water-loss observed following decapitation appeared not to result from significant increase in excretory output or loss of water through the spiracles. It is suggested that integumentary transpiration may be affected by a blood-borne factor, or factors, which originate in the brain and corpus cardiacum.

STUDY ON PHYSICAL AND SENSORICAL CHARACTERISTICS OF FLESH RESTRUCTURED WITH SAGO CATFISH JERKY

2014 ◽  
Vol 4 (2) ◽  
pp. 55-64
Author(s):  
Amir Jayani ◽  
Zulman Efendi ◽  
Devi Silsia
Keyword(s):  
Physical Properties ◽  
Water Content ◽  
Analysis Of Variance ◽  
Test Data ◽  
Organoleptic Test ◽  
Significant Difference

This study aims to gain influence the thickness and concentration variations affect the characteristics of sago binder physical properties of catfish jerky. As well as getting influence the thickness and concentration variations affect the level of binder sago joy panelists in terms of organoleptic test. Data were analyzed by analysis of variance using the Analysis Of Variance (ANOVA). If there is a significant difference followed by a further test of DMRT 5% level (physical properties). While the hedonic test performed using Kruskal Wallis analysis. Results uniformity analysis (ANOVA) showed catfish fillet thickness and concentration of sago affect the physical properties of the water content and the level of violence. Where catfish jerky using sago binder 5% and 10% significantly different. The use of sago binder 5% and 10% led to an increase in water content. Besides the addition of the binder resulted in increasing levels of violence catfish jerky. Based on the statistics found that the influence of the thickness and concentration of the binder sago aroma, flavor and color of the sixth jerky catfish were not significantly different. But the texture was significantly different.

Simultaneous Measurements of Spiracular and Cuticular Water Losses in Periplaneta Americana: Implications for Whole-Animal Mass Loss Studies

1991 ◽  
Vol 161 (1) ◽  
pp. 439-453 ◽  
Author(s):  
J. MACHIN ◽  
P. KESTLER ◽  
G. J. LAMPERT
Keyword(s):  
Water Loss ◽  
Periplaneta Americana ◽  
Water Losses ◽  
Initial Water ◽  
Variable Activity ◽  
Cuticular Permeability ◽  
Order Of Magnitude ◽  
Animal Mass ◽  
Principal Contributor ◽  
Water Contents

Spiracular and cutaneous water loss through the cuticle and spiracles of Periplaneta americana was measured in animals of differing initial water contents under controlled temperature, humidity and airflow conditions, by continuous weighing (resolution ±10μg). Stable water loss rates (2.09×10−8 to 3.47×10−8gh−1cm−2Pa−1) were as much as an order of magnitude less than those reported in earlier studies employing intermittent weighing techniques. We suggest that increased water loss caused by substantial increases in ventilatory water loss during the episodic disturbances required by intermittent weighing is the principal contributor to this discrepancy. Water losses, as well as the interval between spiracular ventilations, decreased with water content. However, greater variation was primarily due to interruptions of the regular cyclic pattern of ventilation by highly variable, activity-related bouts of increased ventilatory loss. Variations in water loss appear to be too large and too rapid to be convincingly explained in terms of cuticular conductance. Our results suggest that previous experiments using 5% CO2 anaesthesia, linking changes in total water loss to the conducting properties of the cuticle, were not valid. There seems to be no adaptive value for the proposed voluntary increases in cuticular permeability in an animal where ventilatory water losses can be so high.

scholarly journals Diversity, Abundance, and Foraging Behavior of Ants (Hymenoptera: Formicidae) Scavenging on American Cockroach in Various Habitats of Nasarawa State, Nigeria

2020 ◽  
Vol 43 (4) ◽  
Author(s):  
Mohammed Ahmed Ashigar ◽  
Abdul Hafiz Ab Majid
Keyword(s):  
Rural Communities ◽  
Relative Abundance ◽  
Periplaneta Americana ◽  
Vital Role ◽  
American Cockroach ◽  
Conservation Implications ◽  
Residential Communities ◽  
Food Borne ◽  
Significant Difference ◽  
Paratrechina Longicornis

Ants play a vital role in removing dead arthropods from the environment. Complex foraging patterns are used by ants to locate food items and overwhelm even larger insects such as cockroach. Consequently, the biotic interaction between the ants and the American cockroach, Periplaneta americana, another home infesting and a vector of major food-borne diseases, may lead to microbial handover and ease the spread of mechanically transmitted human pathogenic microbes. This study was done to determine the diversity and abundance of cockroach-foraging ants in Nasarawa State, Nigeria. Ten households were randomly selected from 14 locations: 5 residential communities from three most urbanized areas (Lafia, Akwanga, and Keffi) and 5 rural communities. Four remaining locations were nonresidential from Lafia and Akwanga, respectively. A total of 1,364 ants belonging to three subfamilies (Myrmicinae, Formicinae, and Ponerinae) were collected from 140 households. Pheidole rugaticeps Emery recorded the highest relative abundance (52%) followed by Pheidole decarinata Santschi (16%), Pheidole sp. (17%), Camponotus maculatus (7%), Paratrechina longicornis (7%), while both Crematogaster sp. and Brachyponera sennaarensis recorded the lowest relative abundance (1%). There is a significant difference in the species diversity between the urban and the rural communities. Pheidole rugaticeps, P. decarinata, Pheidole sp., and P. longicornis were more organized in foraging and operating in group by recruiting nest-mate for collecting fragments of dead cockroach. Studies on the epidemiology, conservation implications, and biocontrol potentials of these Pheidole species are recommended.

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