Observations on the bionomics and physiology ofTrebius caudatusandLernaeocera branchialis(Copepoda)

Author(s):  
N. G. Sproston ◽  
P. H. T. Hartley

A study of the distribution ofTrebius caudatusfrom four species ofRajatrawled from two localities of different depths at Plymouth shows that there is a higher infection rate in the deeper water.Both at Roscoff (France) and at Plymouth the mean total rate of infection is about 20%, and the larger fish are more often infected than the smaller. Both sexes are equally parasitized and the copepods tend to collect near orifices on both surfaces of the fish (regions where the mucus secretion is maximum). Immature forms were found at Roscoff in the mucus of the orifices themselves. The collections from both places contained about equal numbers of male and female parasites.Intestinal respiration, a feature common to free living and parasiticcopepods, includes the gaseous exchange through the gut wall, the associated movements stirring the oxygen vector (which is either the external medium taken in by the anus, or the food current when this is the blood of the host), and the circulation of the body fluid as a direct result of these movements. The significance of the gut movements, which include the peculiar two-way peristalsis, is examined in detail inTrebius caudatus and Lernaeocera branchialis: the former has a functional anus which admits the external medium and the latter has a closed anus and employs the blood of the host as the oxygen vector.

Author(s):  
G. M. Spooner

1. The most noticeable response of marine plankton to light, under laboratory conditions, is the formation of groups on the lighted (or opposite) side of the vessel containing them.2. Specimens from such groups were tested under different conditions of illumination, and in all cases they moved in the direction of the light quite irrespective of accompanying changes of intensity in the surroundings.3. Groups form around the line of direction of the light, or the resultant direction when the light is scattered or falling from more directions than one, this being the direct result of individuals moving along the mean path of incidence of the light.4. The behaviour of individuals was examined more closely to distinguish between the two possible ways in which the directed movement could have been brought about, viz. (i) reactions to bilateral inequalities of illumination (here called “true topotaxis”), and (ii) reactions to changes in total illumination of light-receptors (a type of “phobotaxis”). For a number of species it was clearly a case of “true topotaxis,” and very probably for at least the majority of the rest.5. In two very different cases, namely, Acartia clausi and Poecilochaetus serpens, there was no orientation of the body, but nevertheless efficient orientation of the path of movement. It is believed that this is the first occasion on which such behaviour has been described.6. The observations described point to the fact that movement in the direction of incidence of the light, however this may be affected, is general among a wide range of the smaller, free-living, bilaterally symmetrical, marine animals, and would tend to dominate other possible response to light. This behaviour on the part of individuals provides a substantial basis for attempted explanations of the correlations, that have been demonstrated by ecological workers, between the vertical distribution of populations and light-intensity.


1952 ◽  
Vol 29 (1) ◽  
pp. 22-29
Author(s):  
A. D. HOBSON ◽  
W. STEPHENSON ◽  
A. EDEN

The results obtained in this investigation are admittedly not as extensive as is desirable but they allow certain conclusions to be drawn. 1. The sodium and potassium contents of the body fluid of Ascaris lumbricoides are somewhat variable, but these variations do not seem to be dependent upon those of the external medium. 2. The calcium and magnesium contents of the body fluid are relatively constant and are not affected by those of the external medium. 3. The chloride concentration of the body fluid is closely related to and always remains lower than that of the external medium. 4. As shown in Table 2, there is a large gap between the total concentrations of inorganic cations and anions in the intestinal fluid of the pig. Presumably a considerable proportion of the inorganic cations are combined with organic anions, at present undetermined. Exposing the worms to saline media composed of chloride caused a large rise in the internal chloride concentration. This may well be a limiting factor in the life of the animals in such media, and the next step forward would seem to be the fuller analysis of the environment to which they are normally exposed.


1936 ◽  
Vol 13 (3) ◽  
pp. 309-328
Author(s):  
L. E. R. PICKEN

1. In Carcinus maenas: (a) The blood may be hypertonic, isotonic or hypotonic to the external medium. (b) The urine may be hypertonic, isotonic or hypotonic to the blood, and its concentration may differ in the two antennary glands. (c) The hydrostatic pressure of the body fluid is c. 13 cm. of water. (d) The colloid osmotic pressure of the blood is c. 11 cm. of water. (e) The urine probably contains protein and has a colloid osmotic pressure of c. 3 cm. of water. 2. In Potamobius fluviatilis: (a) The blood is hypertonic to the external medium. (b) The urine is hypotonic to the blood but hypertonic to the external medium and its concentration may differ in the two antennary glands. (c) The hydrostatic pressure of the body fluid is c. 20 cm. of water. (d) The colloid osmotic pressure of the blood is c. 15 cm. of water. (e) The urine may contain protein and has a colloid osmotic pressure (calculated) of c. 2 cm. of water. 3. In Peripatopsis spp.: (a) The blood is hypertonic to the urine. (b) The hydrostatic pressure of the body fluid is c. 10 cm. of water. (c) The colloid osmotic pressure (calculated) of the blood is c. 5 cm. of water. (d) The urine may contain protein and has a colloid osmotic pressure (calculated) of c. 2.5 cm. of water. 4. It is concluded that filtration is possible and that secretion and resorption almost certainly occur in the formation of the urine. 5. A microthermopile is described. 6. Methods are described for measuring the hydrostatic pressure and the colloid osmotic pressures of the body fluids in small animals.


2014 ◽  
Vol 11 (1) ◽  
pp. 11-14
Author(s):  
AHM Mostafa Kamal ◽  
Shamim Ara ◽  
Md Mesbahul Hoque ◽  
Khadeza Khatun ◽  
Kazi Afzalur Rahman

Context : The bones of the body are the last to pass away after death, next to enamel of teeth. Hence, in establishing the personal identity with respect to sex, age and stature, medico legal experts, anatomists and anthropologists use the skeletal materials for giving their opinion. Sex-dependent differences have been noted in the pelvic bone anatomy, and so differences exist in male and female sacrum. The aim of this study was to collect data regarding morphometric measurements of maximum length and breadth of sacrum and to find out possible variations of sacral index in different individuals in relation to sex. Material and Methods: A Cross-sectional, analytical type of study was conducted in the department of Anatomy, Dhaka Medical College, on 172 (one hundred seventy two) adult human dry sacra of unknown sex. The study samples were distributed in male and female sex groups by discriminant function analysis. All the samples were studied morphologically. Sacral length and breadth were measured with the help of digital slide calipers. Result : The mean sacral index in male and female were 97.88±6.16 % and 112.69±10.17 % respectively. Female has the greater sacral index than male (P<0.001) Conclusion: Sexing of sacrum, by sacral index method is relevant and significant DOI: http://dx.doi.org/10.3329/bja.v11i1.20502 Bangladesh Journal of Anatomy, January 2013, Vol. 11 No. 1 pp 11-14


1952 ◽  
Vol 29 (1) ◽  
pp. 1-21
Author(s):  
A. D. HOBSON ◽  
W. STEPHENSON ◽  
L. C. BEADLE

1. The total osmotic pressure, electrical conductivity and chloride concentration of the body fluid of Ascaris lumbricoides and of the intestinal contents of the pig have been measured. 2. The results obtained agree with the observations of previous workers that Ascaris normally lives in a hypertonic medium and that it swells or shrinks in saline media which are too dilute or too concentrated. 3. Experiments comparing the behaviour of normal and ligatured animals show that both the body wall and the wall of the alimentary canal are surfaces through which water can pass. 4. 30% sea water has been used as a balanced saline medium for keeping the worms alive in the laboratory. This concentration was selected as being the one in which there was least change in the body weight of the animals exposed to it. 5. The osmotic pressure of the body fluid of worms kept in 30% sea water is approximately the same as in animals taken directly from the pig's intestine. The body fluid of fresh worms is hypertonic to 30% sea water and hypotonic to the intestinal fluid. In 30% sea water the normal osmotic gradient across the body wall is therefore reversed. 6. In 30% sea water the total ionic concentration (as measured by the conductivity) decreases slightly, but the chloride concentration increases by about 50%, although still remaining much below that of the external medium. 7. Experiments in which the animals were allowed to come into equilibrium with various concentrations of sea water from 20 to 40% show that there are corresponding changes in the osmotic pressure of the body fluid which is, however, always slightly above that of the saline medium. The conductivity also changes in a similar manner but is always less than that of the medium, and the difference between the two becomes progressively greater the more concentrated the medium. 8. The chloride concentration of the body fluid varies with but is always below that of the external medium, whether this is intestinal fluid or one of the saline media. In the latter the difference between the internal and external chloride concentrations is least in 20% sea water and becomes progressively greater as the concentration of the medium is increased. 9. Experiments with ligatured worms and with eviscerated cylinders of the body wall show that these share the capacity of the normal worm to maintain the chloride concentration of the body fluid below that of the environment. This power is not possessed by cylinders composed of the cuticle alone. 10. If the worms which have had their internal chloride concentration raised by exposure to 30% sea water are transferred to a medium composed of equal volumes of 30% sea water and isotonic sodium nitrate solution, the chloride concentration of the body fluid is reduced to a value below that of the external medium. This phenomenon is also displayed by worms ligatured after removal from the 30% sea water and, to an even more marked degree, by eviscerated cylinders of the body wall. 11. It is concluded that Ascaris is able to maintain the chloride concentration of the body fluid below that of the external medium by an process of chloride excretion against a concentration gradient, and that this mechanism is resident in the body wall, the cuticle being freely permeable to chloride.


2013 ◽  
Vol 40 (2) ◽  
pp. 189-196 ◽  
Author(s):  
MZR Majumder ◽  
Mohan Kumar Dash ◽  
Rafia Akhtar Khan ◽  
Humayun Reza Khan

The biology of Boettcherisca peregrina (Robineau-Desvoidy, 1830) (Diptera: Sarcophagidae) was studied in the laboratory (25 ± 5ºC, R.H. 70 ± 10% and 12 h light: 12 h dark cycle ). There were four definite life stages, such as egg, larva, pupa and adult, in its life cycle. The mean duration of the life cycle was 13.19 ± 1.32 days. The egg was creamy white color, cylindrical, rounded at both ends. The egg shell was comparatively thick and hard. There were three larval instars. The larvae of B. peregrina were acephalous and apodus type. The transparent 12 segmented larva possessed a pair of mouth hook, bands of small backwardly directed black micro spines, a pair of prothorasic spiracle and a pair of posterior spiracle. The 1st larvae were relatively more transparent at the time of hatching. The second instar larvae were voracious feeder. The body size increased largely during the third instar. They were deep creamy to pale brownish in color. The pupae of B. peregrina were coarctate adecticous type. The posterior end of the puparium was rounded and the anterior end was slightly pointed. The adults were metallic brown in color. The males were smaller in size than the females. The mean incubation period was 11.6 ± 2.70 hours, and the larval, post-feeding and pupal periods were 102.22 ± 7.85 hours, 75.4 ± 3.57 hours, and 5.81 ± 1.30 days, respectively. The longevity of the mated male and female adults (36.9 ± 2.46 days and 27.2 ± 2.25 days, respectively) were more than that of the unmated ones (23.6 ± 2.25 days and 18.3 ± 1.5 days, respectively). The protein fed adults lived longer than the protein unfed ones.The male always lived longer than the female. DOI: http://dx.doi.org/10.3329/bjz.v40i2.14312 Bangladesh J. Zool. 40(2): 189-196, 2012


2018 ◽  
Vol 51 (3) ◽  
pp. 121-124
Author(s):  
Mohammed Adam ◽  
Barth Izuchukwu Onyeanusi ◽  
Joseph Olusegun Hambolu ◽  
Suleiman Folorunsho Ambali ◽  
Chikera Samuel Ibe

Abstract The aim of this study was to obtain base-line morphometric data on the whole brain and brainstem in the adult male and female helmeted guinea fowl (Numida meleagris), and compare the result in the two sexes. Brain samples of seventy adult helmeted guinea fowls, comprising 35 males and 35 females, intended for slaughter, were extracted for the study. The body weights for both male and female helmeted guinea fowls were 1247 ± 5.51 g and 1230 ± 4.85 g, respectively. The mean brain weights were 3.39 ± 0.02 g and 3.47 ± 0.18 g for male and female, respectively, and the difference in the values was not significant (P > 0.05). The lengths of the brain and medulla oblongata, as well as the lengths of the midbrain and mesencephalic tectum, did not differ between the two sexes. Neither the mean weights nor lengths of the pons differed between the two sexes. In conclusion, the results of this study showed that there was no sex dimorphism observed in the morphometry of the midbrain, medulla oblongata and pons in the helmeted guinea fowl.


2018 ◽  
Vol 51 (3) ◽  
pp. 121-124
Author(s):  
Mohammed Adam ◽  
Barth Izuchukwu Onyeanusi ◽  
Joseph Olusegun Hambolu ◽  
Suleiman Folorunsho Ambali ◽  
Chikera Samuel Ibe

Abstract The aim of this study was to obtain base-line morphometric data on the whole brain and brainstem in the adult male and female helmeted guinea fowl (Numida meleagris), and compare the result in the two sexes. Brain samples of seventy adult helmeted guinea fowls, comprising 35 males and 35 females, intended for slaughter, were extracted for the study. The body weights for both male and female helmeted guinea fowls were 1247 ± 5.51 g and 1230 ± 4.85 g, respectively. The mean brain weights were 3.39 ± 0.02 g and 3.47 ± 0.18 g for male and female, respectively, and the difference in the values was not significant (P > 0.05). The lengths of the brain and medulla oblongata, as well as the lengths of the midbrain and mesencephalic tectum, did not differ between the two sexes. Neither the mean weights nor lengths of the pons differed between the two sexes. In conclusion, the results of this study showed that there was no sex dimorphism observed in the morphometry of the midbrain, medulla oblongata and pons in the helmeted guinea fowl.


2020 ◽  
Vol 47 (1) ◽  
pp. 89
Author(s):  
Daniel J. D. Natusch ◽  
Jessica A. Lyons ◽  
Mumpuni ◽  
Awal Riyanto ◽  
Syarifah Khadiejah

Abstract ContextEach year, millions of reptile skins are commercially exported from Southeast Asia for exotic leathers. Quotas are commonly used to regulate this trade, but quotas are sometimes exceeded and do little to ensure harvest sustainability. AimsTo explore the relationship between the size of live pythons and their skins, and to assess whether skin measurements can be used to enforce the application of limits on the size of harvested snakes. MethodsWe measured the body size of three heavily harvested python species (Malayopython reticulatus, Python breitensteini and Python brongersmai) in Indonesia and Malaysia and examined the relationship with skin length, skin width, the size of the ventral scale and its adjacent dorsal scale. Key resultsMeasurements of 2261 pythons showed strong relationships between the size of live pythons and measurements made on their skins. Skins can be stretched 30% longer than the body length of snakes from which they came and inter-facility and country differences in stretching technique result in different relationships between the sizes of live snakes and the measurements made on their skins. Male and female Malayopython reticulatus differed in their skin dimensions relative to the size of the live snake, but these differences were minor. ConclusionsDespite variations in stretching techniques, in functional terms, this variation is minor (maximum 3.5% relative to each mean measurement) and does not limit application of skin sizes for regulating trade within an acceptable level of error. However, differences in the stretched length of Indonesian and Malaysian skins were much greater (5.9% of the mean length of skins), and, thus, each country should apply its own limits and predictive tools. ImplicationsThe strong relationship between the skin size and the size of the live snake offers great potential for regulating trade by using skin-size limits. Inspection of the size of skins can be used to enforce harvest-size limits and focus harvesting away from sexes and life stages most critical for population persistence. This management tool has numerous advantages over current regulatory practices (quotas) and should be considered for management of trade in Asian reptile skins.


Al-Risalah ◽  
2018 ◽  
Vol 8 (2) ◽  
pp. 126-148
Author(s):  
Ay Maryani

This study describes the religious behavior of UIN Syarif Hidayatullah Jakarta students. The variables used are internal and external environment as independent variable and religious behavior as dependent variable. The internal environment variable consists of gender factor, (male and female). The external environmental variables comprise the faculty environment, the present resident and the place to grow. The present resident consist of dormitories, boarding houses and parents' homes and the place to grow consist of urban and rural environment. Religious behavior variables consist of habluminallah behavior and habluminannas behavior. Habluminallah's behavior measured by (1) knowledge of faith and worship, (2) attitudes toward faith and worship, and (3) practice of faith and worship. The habluminannas variable measured by (1) Islamic behavior for them self, like honest, discipline and good work / studyethics, trust and concern on legality, (2) Islamic behavior with others, like generous, cooperation, caring, respect to the people's rights and tolerance and (3) Islamic behavior for the natural surroundings, like love of nature and nature conservation efforts. The methodology used was (1) Statistical descriptive, (2) MANOVA (Multivariate Analysis of Variance) and (3) Independent sample t-test. The results showed the religious behavior UIN Syarif Hidayatullah Jakarta students has a very good category. This is indicated by the mean values for the behavior of haluminallah and habluminannas of 158.85 and 178.76,  espectively. The average value of habluminallah behaviour in the range of values "145-180" with the category of "very good" and habluminannas behavior in the range value "165-205" with the category "very good. Habluminallah and habluminannas behavior are different for each faculty. This is indicated by the significance level of Pillai Trace, Wilk Lambda, Hotelling Trace, Roy's Largest Root of 0.00 (<0.05). Habluminallah and habluminannas behavior are the same for respondents who live in dormitories, boarding houses, and parents' homes. This is indicated by the value of F test and significance at Wilk's Lambda respectively for 2.055 and 0.085 (>0.05). Habluminallah and habluminannas behaviors are similar for urban and rural respondents. This is known from the sig level. (2-tailed) for habluminallah and habluminannas behavior of 0.317 and 0.245 (> 0.05), respectively. Habluminallah and habluminannas behaviors are similar for male and female. This is known from the sig level. (2-tailed) for habluminallah and habluminannas behavior of 0.950 and 0.307 (> 0.05),respectively. The results of this study are expected to be used to develop university policies that can enhance the Islamic values of UIN Syarif Hidayatullah Jakarta.


Sign in / Sign up

Export Citation Format

Share Document