POPULATION STRUCTURE AND BODY WEIGHTS OF SNOWSHOE HARES ON MANITOULIN ISLAND, ONTARIO

1964 ◽  
Vol 42 (6) ◽  
pp. 975-986 ◽  
Author(s):  
Robin Newson ◽  
Antoon de Vos

The age structure and body weight of two snowshoe hare populations, just at or passing a cyclical peak in numbers, were studied over 3 years. The survival of the young was poor. Each winter, the young of the previous summer were already too few to replace all the normally expected losses of adults. Numbers therefore decreased from year to year. Shot samples were biased towards adult females in the breeding season. It appeared that they were feeding more heavily than the males as their gut weights at this time were markedly increased. There was a clear annual cycle in body weight with females consistently heavier than males. Immature hares were lighter than adults during their first winter and remained so until they were at least a year old.

1979 ◽  
Vol 28 (3) ◽  
pp. 297-307 ◽  
Author(s):  
J. F. Quirke

ABSTRACTGroups of spring-born Galway (G) and Fingalway (F) ewe lambs were fed a concentrate diet either ad libitum (H) or at a restricted level (L) during the period 25 July to 16 October 1974 in order to induce differences in body weight at the start of the breeding season. The mean live weights of the GL, GH, FL and FH groups on 16 October 1974 were 37·8 ± 1·3, 44·6 ± 1·3, 35·1 ± 1·1 and 41·9 ± 1·2 kg respectively. More than 95% of the lambs in all four groups attained puberty before 28 February 1975. Galway ewe lambs reached puberty later in the breeding season and were older and heavier at puberty than Fingalways. Animals fed ad libitum were heavier at puberty and attained puberty earlier in the season and at a younger age than those on the restricted feeding regime.Both conception rate and litter size were lower in Galways than Fingalways. There was no evidence of any effect of the nutritional treatments on conception rate or litter size. The mean body weights at puberty for ewes which lambed and those which were barren were 41·9 ± 0·49 and 41·5 ± 0·78 kg respectively. The birth weight and growth rate of the progeny of the ewe lambs was similar for the two breeds and was not influenced by the previous nutritional treatment of the dams. The total lamb mortality between birth and weaning was 40·3%, and 72% of all deaths occurred within 48 h of birth. Losses among twins (48%) were particularly heavy.


1983 ◽  
Vol 10 (3) ◽  
pp. 467 ◽  
Author(s):  
LS Hall

Information on body weight, measurements and breeding is recorded for 96 female and 42 male Isoodon macrourus, trapped in the vicinity of Brisbane. Data are also given on sex ratio, nipple attachment site and mortality for 128 pouch young from 44 litters. I. macrourus is the heaviest peramelid, with a mean body weight of 1046 ( � 263)g for females and 1496 ( � 359)g for males. Seasonal effects on body weight are evident in females but absent in males. Females with pouch young were significantly heavier than those without young for most months of the year. Unlike most other peramelids, I. macrourus has no defined breeding season in south-eastern Queensland. Females produce litters in all months of the year, with a peak in August and a low in June. Litter size averaged 2.9, which is the lowest recorded for the species. Female body weight had a positive linear relationship with litter size (y= 0.001297x + 1.444). Sex ratio of adults was 1:1, but that of pouch young favoured males 1:0.8. Of the eight pouch teats available, young favoured the four anterior nipples (72 v.56) and males outnumbered females on the left-side nipples. Survival rate of pouch young, as indicated by litter size from 0 to 50 days, showed no variation but there appears to be a high mortality for young after they leave the pouch and before they reach a body weight of 500 g.


1977 ◽  
Vol 55 (3) ◽  
pp. 634-637 ◽  
Author(s):  
E. O. Höhn ◽  
J. G. Stelfox

Adrenal and body weights of snowshoe hares from three areas in which hare population densities differed markedly were determined in a search for evidence of adrenal enlargement in the course of the population cycle. In the first area hares were in a sudden decline after a peak. Dead hares were found there in some numbers. Hare populations in the other two areas were still rising (population peaks occurred 18 months after sampling), but hare density was considerably greater in the second as compared with the third area. There were no significant differences in absolute adrenal weight between any of the groups. Relative adrenal weights were also similar, except for significantly higher relative adrenal weights in hares found dead as compared with those shot, but this was apparently due merely to the lower body weights of animals found dead compared with those killed. There was no evidence of significant differences in relative adrenal weight according to sex or age. No gastric ulcers were found in 26 hares taken from a population at the peak of the cycle.


1995 ◽  
Vol 73 (4) ◽  
pp. 713-722 ◽  
Author(s):  
A. Kari Stuart-Smith ◽  
Stan Boutin

We examined the extent and impact of predation on red squirrels (Tamiasciurus hudsonicus) during a cyclic decline of snowshoe hares in the southwestern Yukon, Canada. We monitored survival of squirrels on three control grids and a predator exclosure from March 1991 through August 1993. On controls, adult survival during the breeding season decreased from 1991, when snowshoe hare populations were high, to 1992, when hare populations declined rapidly. Survival increased slightly in 1993, when hare and predator populations were very low. Similarly, adult survival during winter was lower in 1992 – 1993 than in 1991 – 1992. Adult survival on the exclosure remained similar in each breeding season but declined during winter 1992 – 1993. Adult survival was similar on the controls and the exclosure in each year except during winter 1991–1992 and the 1992 breeding season, when it was lower on the controls. There was no difference in juvenile survival between the controls and the exclosure. Despite the decrease in adult survival due to predation, there was no population decline on any of the control grids. We conclude that predation did not have a measurable impact on red squirrel densities at Kluane and that it is unlikely red squirrels show 10-year population cycles in conjunction with snowshoe hares.


2014 ◽  
Vol 84 (1-2) ◽  
pp. 5-11 ◽  
Author(s):  
Eun Y. Jung ◽  
Sung C. Jun ◽  
Un J. Chang ◽  
Hyung J. Suh

Previously, we have found that the addition of L-ascorbic acid to chitosan enhanced the reduction in body weight gain in guinea pigs fed a high-fat diet. We hypothesized that the addition of L-ascorbic acid to chitosan would accelerate the reduction of body weight in humans, similar to the animal model. Overweight subjects administered chitosan with or without L-ascorbic acid for 8 weeks, were assigned to three groups: Control group (N = 26, placebo, vehicle only), Chito group (N = 27, 3 g/day chitosan), and Chito-vita group (N = 27, 3 g/day chitosan plus 2 g/day L-ascorbic acid). The body weights and body mass index (BMI) of the Chito and Chito-vita groups decreased significantly (p < 0.05) compared to the Control group. The BMI of the Chito-vita group decreased significantly compared to the Chito group (Chito: -1.0 kg/m2 vs. Chito-vita: -1.6 kg/m2, p < 0.05). The results showed that the chitosan enhanced reduction of body weight and BMI was accentuated by the addition of L-ascorbic acid. The fat mass, percentage body fat, body circumference, and skinfold thickness in the Chito and Chito-vita groups decreased more than the Control group; however, these parameters were not significantly different between the three groups. Chitosan combined with L-ascorbic acid may be useful for controlling body weight.


2020 ◽  
Vol 20 (8) ◽  
pp. 1262-1267
Author(s):  
Haojun Yang ◽  
Hanyang Liu ◽  
YuWen Jiao ◽  
Jun Qian

Background: G protein-coupled bile acid receptor (TGR5) is involved in a number of metabolic diseases. The aim of this study was to identify the role of TGR5 after Roux-en-Y gastric bypass (GBP). Methods: Wild type and TGR5 knockout mice (tgr5-/-) were fed a high-fat diet (HFD) to establish the obesity model. GBP was performed. The changes in body weight and food intake were measured. The levels of TGR5 and peptide YY (PYY) were evaluated by RT-PCR, Western blot, and ELISA. Moreover, the L-cells were separated from wild type and tgr5-/- mice. The levels of PYY in L-cells were evaluated by ELISA. Results: The body weights were significantly decreased after GBP in wild type mice (p<0.05), but not tgr5-/- mice (p>0.05). Food intake was reduced after GBP in wild type mice, but also not significantly affected in tgr5-/- mice (p>0.05). The levels of PYY were significantly increased after GBP compared with the sham group (p<0.05); however, in tgr5-/- mice the expression of PYY was not significantly affected (p>0.05). After INT-777 stimulation in L-cells obtained from murine intestines, the levels of PYY were significantly increased in L-cells tgr5+/+ (p<0.05). Conclusion: Our study suggests that GBP up-regulated the expression of TGR5 in murine intestines, and increased the levels of PYY, which further reduced food intake and decreased the body weight.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shota Ichikawa ◽  
Misaki Hamada ◽  
Hiroyuki Sugimori

AbstractBody weight is an indispensable parameter for determination of contrast medium dose, appropriate drug dosing, or management of radiation dose. However, we cannot always determine the accurate patient body weight at the time of computed tomography (CT) scanning, especially in emergency care. Time-efficient methods to estimate body weight with high accuracy before diagnostic CT scans currently do not exist. In this study, on the basis of 1831 chest and 519 abdominal CT scout images with the corresponding body weights, we developed and evaluated deep-learning models capable of automatically predicting body weight from CT scout images. In the model performance assessment, there were strong correlations between the actual and predicted body weights in both chest (ρ = 0.947, p < 0.001) and abdominal datasets (ρ = 0.869, p < 0.001). The mean absolute errors were 2.75 kg and 4.77 kg for the chest and abdominal datasets, respectively. Our proposed method with deep learning is useful for estimating body weights from CT scout images with clinically acceptable accuracy and potentially could be useful for determining the contrast medium dose and CT dose management in adult patients with unknown body weight.


2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii45-ii45
Author(s):  
Sharon Gardner ◽  
Carl Koschmann ◽  
Rohinton S Tarapore ◽  
Jeffrey Allen ◽  
Wafik Zaky ◽  
...  

Abstract ONC201, an anti-cancer DRD2 antagonist and ClpP agonist, is in Phase II trials for adult H3 K27M-mutant diffuse midline gliomas. In adults, the recommended phase 2 dose (RP2D) of 625mg ONC201 once a week has been established as a biologically active dose that is well tolerated. Radiographic regressions with single agent ONC201 have been reported in adult recurrent H3 K27M-mutant glioma patients. This multi-arm, dose-escalation and dose-expansion trial determined the pediatric RP2D of ONC201 administered as an oral capsule (Arm A) or liquid formulation (Arm E) in post-radiation H3 K27M-mutant glioma (Arm A) or in newly diagnosed DIPG (Arm B) patients. Molecular assessments include intratumoral ONC201 concentrations (Arm C) and CSF H3 K27M DNA levels (Arm D). Enrollment as of April 30, 2020 is complete in Arm A (22) and Arm E (26) and continues in Arm B (18/24), Arm C (5/12), and Arm D (22/24). The RP2D of weekly 625mg ONC201 scaled by body weight was confirmed when administered as a capsule or a liquid formulation as a single agent or in combination with radiation without dose-limiting toxicity. The most frequent adverse events regardless of attribution to the drug were predominantly low grade: ONC201 capsule alone was headache (54.5%), nausea (36.4%), and fatigue (36.4%); ONC201 liquid formulation was vomiting (31.8%), headache (22.7%), VIth nerve disorder (22.7%); ONC201 capsules in combination with radiation (Arm B) was headache (47.1%), vomiting (52.9%), nausea (41.2%). Pharmacokinetic analysis in plasma of Arm A patients revealed T1/2: 8.4h; Tmax: 2.1h; Cmax: 2.3ug/mL; AUC0-tlast: 16.4ug/mL, with similar exposure across body weights. In conclusion, when scaled by body weight the ONC201 capsule or liquid formulation alone or in combination with radiation were associated with safety and pharmacokinetic profiles in pediatric H3 K27M-mutant diffuse midline glioma patients that are similar to the experience in adults.


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