scholarly journals Some Aspects of Osmotic Regulation in Lampreys

1956 ◽  
Vol 33 (2) ◽  
pp. 431-447 ◽  
Author(s):  
M. W. HARDISTY

1. The mean osmolar concentration (expressed as mM. NaCl/1.) of the serum for Lampetra planeri was found to be 110 mM. in the ammocoete and 113 mM. in the adult. For adult L. fluviatilis serum in November the mean osmolar concentration was 143 mM. and in March 136 mM. 2. In adult planeri the Cl concentration of the body fluids accounted for nearly 90% of the total concentration as compared with only 58% in the serum of the ammocoete. Adult fluviatilis kept in tap water throughout the winter appeared to show an increase in Cl levels. 3. Evidence has been produced to support the view that the differences observed in water, fat and Cl content of ammocoete and adult planeri and adult fluviatilis are consequences of the period of starvation preceding sexual maturity. 4. Pronounced seasonal variations have been found in the fat and Cl content of ammocoetes of planeri. 5. The osmotic uptake of water has been determined for adults of both species in fresh water. In planeri the rate of uptake for unit body weight is about four times as great as in fluviatilis. 6. Observations have also been made on the osmotic loss of water of ammocoete and adult planeri and of adult fluviatilis in sea water of different concentrations. For unit body weight osmotic loss of water in planeri is about twice that of fluviatilis. 7. Total losses of Cl have been determined for ammocoete and adult planeri in distilled water and their effects on internal Cl levels have been studied. Observations have also been made on the active uptake of Cl. 8. Acclimatization experiments on ammocoetes and adult planeri and on adult fluviatilis have failed to produce any evidence of regulation in sea water.

1969 ◽  
Vol 51 (1) ◽  
pp. 11-16
Author(s):  
R. BINNS

1. The space measured by inulin distribution, the ‘inulin volume’, has been determined, and represents approximately 20% of the body weight in crabs ranging in size from 20.0 to 57.2 g. 2. After the injection of labelled inulin into crabs, the increase in activity of the medium is equal to the fall in blood inulin in all dilutions of sea water. Clearance of inulin from the blood is due only to urine production, and therefore the molecule can be used for quantitative investigations of antennal gland function. 3. Urine production in various concentrations of sea water has been determined by measuring the clearance of inulin from the blood and the rates at which the tracer appeared in the external media. By these methods the mean rate of urine production in 100% sea water was estimated to be 4.4% body weight per day. In dilute sea water the rate of urine production increases; for example, in 50% sea water the urine flow is four times greater than in normal sea water.


1964 ◽  
Vol 12 (3) ◽  
pp. 322 ◽  
Author(s):  
AG Lyne

A study has been made of 521 bandicoots (Perameles nasuta, 324; P. gunnii, 111 ; Isoodon obesulus, 86). Near Sydney, P. nasuta breeds all the year round with no indication of any peaks of breeding activity. Limited observations on P. gunnii and I. obesulus in Tasmania also suggest that births occur in every season of the year. Parturition of a single individual of P. nasuta was witnessed. Fifteen new-born specimens of this species were measured and body weight records were obtained for five of them. The average dimensions of these specimens, and consecutive measurements of three specimens born in captivity and of known age, were used to age pouch young of unknown age. Age changes in the appearance of P. nasuta are described and illustrated. Hair emerges on the trunk at about 40 days after birth and at 2 months the coat is similar to that of the adult. The rate of body growth is extremely rapid just prior to the opening of the eyes (usually at 45-48 days), and the young first appear outside the pouch several days later. The pouch contains eight teats, and the mean litter sizes were: P. nasuta, 2.44 (52 litters); P. gunnii, 2.23 (22 litters); I. obesulus, 2.33 (9 litters). In 47 litters of P. nasuta, 73 young were on teats of the left side compared with 46 on the right side of the pouch. The sexes were equally represented in the pouch young of the three species examined. In P. nasuta, sexual maturity is reached at about 450 g in females and about 650 g in males. The linear equivalence (cube root of the body weight) is used as an overall measure of size with which the parts of the body are compared.


2019 ◽  
Vol 15 (02) ◽  
pp. 14-17
Author(s):  
K K Hadiya ◽  
A J Dhami ◽  
D V Chaudhari ◽  
P M Lunagariya

This study was initiated on 24 prepubertal Holstein x Kankrej crossbred heifers of nearly identical age (7-9 months) and body weight (130-140 kg) at University farm to evaluate the effect of high plane of nutrition on blood biochemical and minerals profile and the age at puberty. Twelve heifers were managed under routine farm feeding (control) and the rest 12 under ideal optimum feeding regime (treatment) that included extra 1 kg concentrate, 30 g min mix and ad-lib dry fodder. The body weight and ovarian ultrasonography together with blood sampling was carried out at monthly interval from 10 to 18 months of age to study the ovarian dynamics and blood biochemical changes. High plane of nutrition to growing heifers was beneficial in reducing the age of onset of puberty (by 2-3 months) compared to routine farm fed group. The mean plasma total protein and cholesterol concentrations showed a rising trend with significant variations from 10 to 16 months of age, where it got mostly stabilized indicating adult profile. The activity of enzymes GOT and GPT also rose gradually and significantly from 10 months till 14-15 months of age, and thereafter it remained more or less static till 18 months of age. The levels of both these enzymes were higher, with lower protein and cholesterol, in control than the treatment group from 15-16 months of age onwards. The mean plasma levels of both calcium and phosphorus increased gradually and significantly with advancing age till 16-17 months of age, with little higher values in supplemented than a control group. The plasma levels of zinc, iron, copper, and cobalt also showed rising trend with significant differences between 10th and 12th-14th months of age, and from 15th to 18th months of age the levels were statistically the same in all the groups with slightly higher values in the treatment group.


1968 ◽  
Vol 48 (2) ◽  
pp. 359-380
Author(s):  
D. W. SUTCLIFFE

1. Sodium uptake and loss rates are given for three gammarids acclimatized to media ranging from fresh water to undiluted sea water. 2. In Gammarus zaddachi and G. tigrinus the sodium transporting system at the body surface is half-saturated at an external concentration of about 1 mM/l. and fully saturated at about 10 mM/l. sodium. In Marinogammarus finmarchicus the respective concentrations are six to ten times higher. 3. M. finmarchicus is more permeable to water and salts than G. zaddachi and G. tigrinus. Estimated urine flow rates were equivalent to 6.5% body weight/hr./ osmole gradient at 10°C. in M. finmarchicus and 2.8% body weight/hr./osmole gradient in G. zaddachi. The permeability of the body surface to outward diffusion of sodium was four times higher in M. finmarchicus, but sodium losses across the body surface represent at least 50% of the total losses in both M. finmarchicus and G. zaddachi. 4. Calculations suggest that G. zaddachi produces urine slightly hypotonic to the blood when acclimatized to the range 20% down to 2% sea water. In fresh water the urine sodium concentration is reduced to a very low level. 5. The process of adaptation to fresh water in gammarid crustaceans is illustrated with reference to a series of species from marine, brackish and freshwater habitats.


1971 ◽  
Vol 55 (3) ◽  
pp. 651-665 ◽  
Author(s):  
G. M. HUGHES ◽  
R. GAYMER ◽  
MARGARET MOORE ◽  
A. J. WOAKES

1. The O2 consumption and CO2 release of nine giant tortoises Testudo gigantea (weight range 118 g-35·5 kg) were measured at a temperature of about 25·5°C. Four European tortoises Testudo hermanni (weight range 640 g-2·16 kg) were also used. The mean RQ values obtained were 1·01 for T. gigantea and 0·97 for T. hermanni. These values were not influenced by activity or size. 2. The data was analysed by plotting log/log regression lines relating body weight to O2 consumption. Both maximum and minimum metabolic rates recorded for each individual T. gigantea showed a negative correlation with body weight. For active rates the relation was O2 consumption = 140·8W0·97, whereas for inactive animals O2 consumption = 45·47W0·82. 3. The maximum rates were obtained from animals that were observed to be active in the respirometer and the minimum rates from animals that remained quiet throughout. The scope for activity increased with body size, being 82 ml/kg/h for animals of 100 g and 103 ml/kg/h for 100 kg animals. The corresponding ratio between maximum and minimum rates increases from about 2 to 6 for the same weight range. 4. Values for metabolic rate in T. hermanni seem to be rather lower than in T. gigantea. Analysis of the relative proportion of the shell and other organs indicates that the shell forms about 31% of the body weight in adult T. hermanni but only about 18% in T. gigantea of similar size. The shell is not appreciably heavier in adult T. gigantea (about 20%). 5. Data obtained for inactive animals is in good agreement with results of other workers using lizards and snakes. Previous evidence suggesting that chelonians show no reduction in metabolic rate with increasing size is not considered to conflict with data obtained in the present work.


2016 ◽  
Vol 7 (2) ◽  
pp. 26
Author(s):  
Wanmi Nathaniel ◽  
Onyeanusi I. Barth ◽  
Nzalak J. Oliver ◽  
Aluwong Tanang

<p class="jbls-body"><span lang="EN-GB">A total of one hundred and seventy-three fertilized eggs were used for morphometry, gross and histological studies. At day 4 of incubation, the mean body weight of the helmeted guinea fowl embryo was 0.6401 ± 0.0211 g. It was at day 10 of incubation that there was an increase in the whole body weight of the embryo to be 0.8650 ± 0.676 g. The whole brain weight indicated relative increased at day 4 as compared to that of the whole body weight. Graphically, there were steady increase in the body, brain and optic lobe weights. Histologically, cells and neurones that make up the optic lobe is probably as a result of the migration of immature cells from the ventricular neuroepithelium. </span></p>


Author(s):  
Iyad Ali ◽  
Naser Shraim ◽  
Wafaa’ Atrash ◽  
Aisha Sirafi ◽  
Huda Abadi

Artificial Sweeteners (AS) are synthetic sugar substitutes that have sweetening potency hundreds of times more than the table sugar (sucrose). Artificial sweeteners are regarded as attractive alternatives to sugar as they add no calories to food intake. There are many hypotheses suggesting that AS may enhance appetite and cause weight gain. The aim of this study was to evaluate the effect of AS on food intake, fluid intake and body weight of mice. Acceptable daily intakes of AS solutions were administered orally to different set of mice for four weeks. The body weight, food consumption and fluid intake were measured. At the same time, the effect of Zingiber officinale extracts (natural appetite suppressor), Thymus vulgaris extracts (natural appetite inducer) and cyproheptadine (an appetite stimulant drug) on body weight of mice was evaluated. Artificial sweeteners consumption cause insignificant changes in body weight (p>0.05). However, the mean consumption of food and solutions varies significantly for some groups. The consumption of AS has no significant effect on body weight and may contribute to weight maintenance and energy balance as substitutes to high caloric sugar


1956 ◽  
Vol 33 (1) ◽  
pp. 29-44 ◽  
Author(s):  
BETTY I. ROOTS

1. The water content of Lumbricus terrestris, after keeping on moist filter-paper for 3 or 4 days, is 84.8% of its body weight. That of Allolobophora chlorotica is 80% of its body weight. Both species can survive a loss of 60% of the body weight, but not much more. 2. Earthworms of the species A. chlorotica, A. terrestris f. longa, Dendrobaena subrubicunda, L. rubellus and L. terrestris are all able to survive from 31 to 50 weeks in soil totally submerged beneath aerated water. The same species, and A. caliginosa can survive for 72-137 days in aerated tap water without food. 3. Garden specimens of A. chlorotica make U-shaped burrows in soil beneath water. They do not irrigate either the burrows or glass tubes. Egg-cocoons of A. chlorotica, taken from culture pots of soil, will hatch under water and the young worms will feed and grow though totally immersed.


Animals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 822 ◽  
Author(s):  
Nalbert ◽  
Czopowicz ◽  
Szaluś-Jordanow ◽  
Moroz ◽  
Mickiewicz ◽  
...  

A longitudinal study was carried out to investigate the influence of two different rearing systems of young kids on their development to sexual maturity. Kids born to small ruminant lentiviruses-infected (SRLV) female goats were split into two groups: the immediately-after-birth weaned group and the unweaned group. Kids’ body weight (BWT) was measured before the first consumption of colostrum, and then at the age of one week, and one, two, four, and seven months. The relationship between the rearing system and BWT at each age was investigated using mixed linear models adjusted for potential confounders. The mean BWT of kids of the immediately-after-birth weaned group was significantly lower at the age of one week, one month, and two months, and then the difference became insignificant. The mean daily body weight gain (DWG) was significantly lower in the immediately-after-birth weaned group during the whole first month of life, but then DWG in both groups became equal. Crude mortality rate did not differ significantly between groups. This study shows that weaning kids immediately after birth does not appear to have any negative impact on kids’ development except transient growth retardation, which is fully compensated until they reach sexual maturity.


1957 ◽  
Vol 8 (1) ◽  
pp. 75 ◽  
Author(s):  
PK Briggs ◽  
MC Franklin ◽  
GL McClymont

Dry adult Merino ewes were fed at daily or weekly intervals on oat grain at levels which provided 4.0, 3.0, or 2.0 lb starch equivalent (S.E.) per sheep per week. The experimental periods were 223, 223, and 181 days respectively. Differences between the mean body weights of the ewes a t the three levels of feeding were highly significant (P < 0.001). Body weight varied only slightly and no losses occurred in ewes fed weekly at the rate of 4.0 lb S.E. per head. Ewes fed daily a t this level had a significantly greater mean body weight (P < 0.001) a t the conclusion of the 223-day experimental period. The addition of a sodium chloride supplement did not improve the body weight or wool production of ewes fed weekly a t the level of 4.0 lb S.E. The mean body weight of ewes fed at the levels of 3.0 or 2.0 lb S.E. per head declined over the first 12 and 18 respectively and thereafter remained relatively constant. There were no significant differences at these levels of feeding between groups fed daily and weekly in respect of body weight, wool production, or survival rates. Ewes fed a t the level of 4.0 lb S.E. grew significantly more wool than those given 3.0 lb S.E. (P < 0.001). Losses were negligible in all groups except those fed a t the level of 2.0 lb S.E. In these groups there were few deaths in the first 16 weeks, but in the subsequent 10 weeks losses totalled 17.1 per cent. Ewes fed a t the level of 2.0 lb S.E. consumed their rations at a significantly slower rate (P < 0.01) than did those fed a t the level of 4.0 lb S.E.


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