Endocrine and behavioral correlates of nesting in Canada geese

1984 ◽  
Vol 62 (5) ◽  
pp. 845-850 ◽  
Author(s):  
Thomas R. Akesson ◽  
Dennis G. Raveling
Keyword(s):  
Reproductive Effort ◽  
Serum Levels ◽  
Egg Laying ◽  
Behavioral Changes ◽  
Canada Geese ◽  
Behavioral Correlates ◽  
Dominance Relations ◽  
One Year ◽  
Androgen Levels ◽  
Exact Timing

Frequencies of social behaviors of captive Canada geese (Branta canadensis moffitti) were compared with serum levels of androgens, estrogens, and corticosterone during two nesting cycles. Behavioral and endocrine patterns were examined for relationships with the timing of nesting. Androgen levels in reproductively active males were correlated with seasonal changes in the expression of a pair-bond behavior known as Cackling and less strongly with behaviors exhibited in an aggressive context. Estrogen levels in paired females were correlated with frequencies of behavioral responses to the mate's Cackling, and, in one year, with Mating Behavior. Correlation between corticosterone levels and behaviors was weak. Few behavioral changes were correlated with hormone variations in nonbreeding geese. Dominance relations were consistently linear among ganders prior to the incubation period. Correlation between average androgen levels and rank was significant in one year only. The timing of nesting was delayed in a newly formed pair and a pair that was renewed after 15 months of separation. Endocrine levels and behavioral performances of ganders of established pairs did not appear to have an accelerating or decelerating effect on the timing of the mate's reproductive effort, suggesting that the exact timing of egg laying was determined by attributes of the females.

scholarly journals Age-Specific Reproduction by Female Laughing Gulls (Larus Atricilla)

The Auk ◽  
2003 ◽  
Vol 120 (2) ◽  
pp. 531-535
Author(s):  
Richard A. Dolbeer ◽  
Glen E. Bernhardt
Keyword(s):  
New York ◽  
Reproductive Effort ◽  
Reproductive Organs ◽  
Egg Laying ◽  
Age Classes ◽  
Left Testis ◽  
One Year ◽  
Ovulatory Follicles ◽  
Laughing Gulls ◽  
Old Females

Abstract The age at which female gulls first reproduce is poorly documented. We examined plumage and reproductive organs of Laughing Gulls (Larus atricilla) collected from May–August 2000–2001 at John F. Kennedy International Airport, New York, to determine age-specific reproductive effort. Each gull was classified as one year old (hatched in previous year), two years old, or ≥3 years old on the basis of color patterns of the hood and tail feathers and fifth primary flight feather. For females, each ovary was examined to determine if post-ovulatory follicles were present. In 2000 and 2001, the first gulls with postovulatory follicles were recorded on 15 and 18 May, respectively. Overall, 54% of the 211 two-year-old female Laughing Gulls collected during June–August showed evidence of egg laying compared to 88% of the 320 gulls ≥3 years old. None of the 50 one-year-old females examined showed evidence of egg laying. Although a lower proportion of two-year-old females laid eggs compared to older gulls, we found no difference (P ≥ 0.06) in mean number of postovulatory follicles or in frequency distribution of numbers of postovulatory follicles for the two age classes for those birds that did lay eggs. Within each sex, mean body mass increased (P < 0.05) with age. Mean left testis length of males increased (P < 0.05) with age. Our findings clearly established that two-year-old female Laughing Gulls can contribute significantly to the annual reproductive effort and that some adult (≥3 years old) females did not lay eggs.

Breeding biology of the Critically Endangered Tahiti MonarchPomarea nigra, a bird with a low productivity

2017 ◽  
Vol 28 (4) ◽  
pp. 606-619 ◽  
Author(s):  
CAROLINE BLANVILLAIN ◽  
THOMAS GHESTEMME ◽  
TEHANI WITHERS ◽  
MARK O’BRIEN
Keyword(s):  
Reproductive Success ◽  
French Polynesia ◽  
Egg Laying ◽  
Breeding Biology ◽  
Critically Endangered ◽  
Tropical Island ◽  
Island Endemics ◽  
Nest Activity ◽  
Considerable Length ◽  
One Year

SummaryWe studied the breeding biology of Tahiti MonarchPomarea nigra, a ‘Critically Endangered’ forest bird endemic to Tahiti (French Polynesia). Nest activity was monitored from 1998 to 2002, and again from 2008 to 2015. During these 12 years, only 2–13 breeding pairs per year produced hatchlings. Egg-laying occurred all year, but usually increased between August and January, peaking around November. Of the 200 nests monitored, 33 (16%) were abandoned shortly after construction, 71 had an egg laid immediately after the nest were completed (34 %) and 96 nests (46 %) had a pre-incubation phase of 18.9 ± 1.9 days (3–62 days;n= 47 nests), during which the birds visited the nest on an irregular basis. Half (49 of 96) of these nests were abandoned before an egg was laid, with incubation subsequently commencing at the remaining nests (n= 47). Although both sexes incubated for an average of 13.6 ± 0.3 days (range 13–15), the female usually spent more time incubating than the male. Only one young per nest was ever observed. The average nestling phase was 15.5 ± 0.7 days (range 13 to 20 days). Parents continue to feed the young after fledging for 74 ± 4.7 days (range 42–174). As with many tropical island endemics, the Tahiti Monarch has low reproductive productivity as indicated by the fact that: 1) only 56% of pairs attempt to lay an egg in any one year, 2) most pairs attempt only one brood per year and 3) the considerable length of the nesting and fledging phases. Because of its low productivity, maximising the reproductive success of the Tahiti Monarch is essential to secure its recovery.

Long-term treatment of acromegaly with the slow-release somatostatin analogue lanreotide

1994 ◽  
Vol 131 (1) ◽  
pp. 20-26 ◽  
Author(s):  
Josef Marek ◽  
Václav Hána ◽  
Michal Kršek ◽  
Vlasta Justová ◽  
France Catus ◽  
...  
Keyword(s):  
Blood Glucose ◽  
Slow Release ◽  
Serum Levels ◽  
Term Treatment ◽  
Somatostatin Analogue ◽  
Tumour Mass ◽  
Long Term Treatment ◽  
Active Acromegaly ◽  
One Year

Marek J, Hána V. Kršek M. Justová V, Catus F, Thomas F. Long-term treatment of acromegaly with the slow-release somatostatin analogue lanreotide. Eur J Endocrinol 1994;131:20–6. ISSN 0804–4643 Thirteen patients with active acromegaly despite previous surgery were treated with 30 mg lanreotide im twice a month for 9 months. In 10 subjects the treatment continued to 19 months. GH serum levels of all patients decreased significantly from an initial value of 32.0 (29.4) μg/l [median (standard error of median)] to 10.0 (3.6) and 19.1 (5.7) after 3 and 9 months of treatment, respectively. In the 10 patients with the treatment longer than one year the decrease in GH was from 46.8 (29.4) μg/l to 12.5 (5.0) and 16.1 (5.3) after 13 and 19 months, respectively. IGF-I serum levels decreased significantly from 1193 (73)μg/l to 782 (99) and 621 (103) after 3 and 9 months, respectively, and were normalized in 3 patients. In the 10 patients treated for longer than one year, levels decreased significantly from 1318 (74)μg/l to 653 (170) and 742 (180) after 13 and 19 months, respectively. IGF BP-3 levels were reduced to the normal range in 6 patients and decreased from 8.7 (1.5)mg/l to 6.4 (0.8) and to 5.4 (1.0) after 3 and 9 months, respectively. In the patients with the 19 months treatment the decrease was from 9.3 (1.6) mg/l to 3.9 (0.9) and 4.8 (0.9) after 13 and 19 months, respectively. The IGF BP-3 to IFG I ratio increased in 7 patients. This elevation significantly correlated with the decrease in bioassayable somatomedin. Prolactin serum levels fell in all patients with increased prolactin secretion. Testosterone plasma levels increased in 4 out of 5 men without replacement therapy. Clinical improvement was observed in all patients. A reduction of tumour mass was observed in five patients and complete disappearance of the tumour in one subject. All patients complained of mild abdominal pain and softened stools for several days following the injections. However, these side effects never required interruption of treatment. Asymptomatic microlithiasis was seen in only one patient after 13 months, which led to treatment being suspended for a period of 3 months after which it was resumed. Fasting serum insulin and insulin area under the curve (AUC) after oral glucose tolerance test (OGTT) fell in all patients. Fasting blood glucose, fructosamine and glucose AUC after OGTT slightly increased during the treatment, but all blood glucose levels (fasting and during OGTT) remained within normal ranges. Lanreotide appears to be a safe and effective treatment in patients with active acromegaly unresolved by surgery. The long-acting formulation avoids the drawbacks associated with either repeated daily injections or continuous infusions of somatostatin analogues. Josef Marek, Third Department of Medicine, Charles University, U nemocnice 1, 128 21 Praha 2, The Czech Republic

scholarly journals A contribution to the study of biology of Curculio elephas Gyll. (Coleoptera, Curculionidae)

2011 ◽  
pp. 19-28
Author(s):  
Milan Drekic ◽  
Ljubodrag Mihajlovic
Keyword(s):  
Life Cycle ◽  
Larval Stage ◽  
Seed Orchard ◽  
Egg Laying ◽  
Pedunculate Oak ◽  
Minor Part ◽  
One Year ◽  
Entomological Laboratory ◽  
A Minor ◽  
Curculio Elephas

One of the insects that feeds on pedunculate oak acorns and reduces its seed yield is Curculio elephas Gyll. The study of Curculio elephas Gyll is necessary because of the severe damages caused by this insect and also owing to its insufficiently investigated biology. The research was conducted in the common oak seed orchard at Banov Brod, forest estate ?Sremska Mitrovica?, and in the entomological laboratory. The adults emerge from the soil chambers from mid July till the beginning of September. The presence of adults, as determined by crown fogging, ranged from the end of July till the beginning of September with the highest number in mid August. After emerging from the soil, females are already fertile with the developed eggs in the ovaries. They start egg laying after 1 to 8 days and they lay from one to seven eggs per day. Egg laying period lasts from 7 to 20 days. Fertility of C. elephas females ranges from 5 to 40 eggs, while their fecundity ranges from 19 to 45 eggs. At the end of the larval stage, larvae bore into the soil and stay there from one to three years. The species hibernates only in the larval stage. C. elephas has a one-year life cycle, while a minor part of the population has a two or three-year life cycle.

scholarly journals Distinct Processing of Selection and Execution Errors in Neural Signatures of Outcome Monitoring

2019 ◽  
Author(s):  
Faisal Mushtaq ◽  
Samuel D. McDougle ◽  
Matt P. Craddock ◽  
Darius E. Parvin ◽  
Jack Brookes ◽  
...  
Keyword(s):  
Behavioral Adjustment ◽  
Behavioral Changes ◽  
Behavioral Correlates ◽  
Feedback Information ◽  
Future Action ◽  
Outcome Monitoring ◽  
Frontal Negativity ◽  
Neural Signature ◽  
The Brain ◽  
Insight Into

AbstractLosing a point playing tennis may result from poor shot selection or poor stroke execution. To explore how the brain responds to these different types of errors, we examined EEG signatures of feedback-related processing while participants performed a simple decision-making task. In Experiment 1, we used a task in which unrewarded outcomes were framed as selection errors, similar to how feedback information is treated in most studies. Consistent with previous work, EEG differences between rewarded and unrewarded trials in the medial frontal negativity (MFN) correlated with behavioral adjustment. In Experiment 2, the task was modified such that unrewarded outcomes could arise from either poor execution or selection. For selection errors, the results replicated that observed in Experiment 1. However, unrewarded outcomes attributed to poor execution produced larger amplitude MFN, alongside an attenuation in activity preceding this component and a subsequent enhanced error positivity (Pe) response in posterior sites. In terms of behavioral correlates, only the degree of the early attenuation and amplitude of the Pe correlated with behavioral adjustment following execution errors relative to reward; the amplitude of the MFN did not correlate with behavioral changes related to execution errors. These results indicate the existence of distinct neural correlates of selection and execution error processing and are consistent with the hypothesis that execution errors can modulate action selection evaluation. More generally, they provide insight into how the brain responds to different classes of error that determine future action.Significance StatementTo learn from mistakes, we must resolve whether decisions that fail to produce rewards are due to poorly selected action plans or badly executed movements. EEG data were obtained to identify and compare the physiological correlates of selection and execution errors, and how these are related to behavioral changes. A neural signature associated with reinforcement learning, a medial frontal negative (MFN) ERP deflection, correlated with behavioral adjustment after selection errors relative to reward outcomes, but not motor execution errors. In contrast, activity preceding and following the MFN response correlated with behavioral adjustment after execution errors relative to reward. These results provide novel insight into how the brain responds to different classes of error that determine future action.

scholarly journals GLYCEMIC AND LIPIDEIC STATUS IN PATIENTS WITH ACUTE MYOCARDIAL INFARCTION

2014 ◽  
Vol 04 (01) ◽  
pp. 009-014
Author(s):  
A. Harish Rao
Keyword(s):  
Myocardial Infarction ◽  
Acute Myocardial Infarction ◽  
Total Cholesterol ◽  
Ldl Cholesterol ◽  
Fasting Glucose ◽  
Hdl Cholesterol ◽  
Serum Levels ◽  
Glucose Levels ◽  
Low Hdl ◽  
One Year

Abstract: Objective: to know the glycemic and lipidaemic status in patients with acute myocardial infarction, and with the secondary objective to know the effect of age, gender, diabetes, smoking, hypertension on fasting glucose and lipid levels. Methods and materials: The 74 patients admitted for acute myocardial infarction during the study period of one year were analysed for fasting glucose values and serum levels of total cholesterol, HDL cholesterol, LDL cholesterol and triglycerides. Results: The mean serum concentrations of total cholesterol, triglycerides, HDL cholesterol and LDL cholesterol were 233.28±45.34, 139.22±41.71, 171.43±36.53 and 27.07±36.53 respectively. Mean levels of total cholesterol, HDL cholesterol, triglycerides and fasting glucose values were not affected by age, gender, BMI, hypertension and smoking. BMI >30kg/m2 was associated with increased levels of total cholesterol(p=0.013) and LDL cholesterol(p=0.014). Also increase LDL cholesterol was seen in male gender(p=0.04). The prevalence of hypercholesterolemia, hypertriglyceridemia and low HDL cholesterol was 82.4%,77% and 78% respectively. Diabetes had no effect on lipid profile. Conclusion: our study highlighted the prevalence of dyslipidemias associated with myocardial infarction but not significant impact of fasting glucose levels.

scholarly journals Screening of Thyroid Function in the First Half of Pregnancy

2016 ◽  
Vol 29 (1) ◽  
pp. 26-31
Author(s):  
Shaila Naznine Tania ◽  
Ferdousi Islam
Keyword(s):  
Pregnant Women ◽  
Thyroid Function ◽  
Serum Levels ◽  
Cross Sectional Study ◽  
Thyroid Disorder ◽  
Eligibility Criteria ◽  
Cross Sectional ◽  
Medical College ◽  
One Year ◽  
Serum Tsh

Objective: The study was conducted to find out any alterations in thyroid function status in first half of pregnancy (up to 20 weeks), with ultimate aim of deciding the usefulness of routine screening of thyroid function in pregnancy.Material and methods: A cross-sectional study was conducted in the department of Obstetrics & Gynaecology, Dhaka Medical College and Hospital, Dhaka, Bangladesh, over a period of one year from July 2011 to June 2012 on pregnant women in their 1st half of pregnancy to screen for the thyroid function. Based on predefined eligibility criteria, a total of 230 pregnant women were purposively included in the study. Thyroid function status was assessed by measuring serum levels of TSH, free thyroxine (FT4), and free tri-iodothyronine (FT3). Women with thyroid disorders were excluded.Results: The mean age of the patients being 24 years. Over 90% of the women were housewife and majority (88.7%) was educated. Over one-quarter of women was overweight with mean body mass index being 22.1 ± 4.4 kg/m2. The women were predominantly multigravida with 56% in 1st trimester 44% in the 1st half of 2nd trimester of pregnancy (13-20 weeks). Based on trimester’s specific range of serum TSH in the 1st and 1st half of 2nd trimester (13-20 weeks) of pregnancy,13% of the patients were hypothyroid and 3% were hyperthyroid thus yielding a total of 37(16%) pregnant women with abnormal thyroid function status.Conclusion: The study concluded that one in every six women may have thyroid disorder in the first half of pregnancy and subclinical hypothyroidism is four times more common than the subclinical hyperthyroidism.Bangladesh J Obstet Gynaecol, 2014; Vol. 29(1) : 26-31

scholarly journals Low Serum Melatonin Levels Prior to Liver Transplantation in Patients with Hepatocellular Carcinoma are Associated with Lower Survival after Liver Transplantation

2019 ◽  
Vol 20 (7) ◽  
pp. 1696
Author(s):  
Leonardo Lorente ◽  
Sergio Rodriguez ◽  
Pablo Sanz ◽  
Pedro Abreu-González ◽  
Agustín González-Rivero ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Liver Transplantation ◽  
Antioxidant Capacity ◽  
Total Antioxidant Capacity ◽  
Serum Levels ◽  
High Serum ◽  
Published Data ◽  
Lower Serum ◽  
Total Antioxidant ◽  
One Year

Melatonin administration has been associated with different benefits in animals and patients suffering from liver diseases. However, there is no published data about circulating melatonin levels in patients with hepatocellular carcinoma (HCC) who underwent liver transplantation (LT). Thus, the objective of this observational and retrospective study was to determine whether patients with HCC with lower serum melatonin levels prior to LT have a higher risk of one-year mortality after LT. We measured serum levels of melatonin, malondialdehyde (to assess lipid peroxidation), and total antioxidant capacity (to assess antioxidant state) before LT. One-year surviving LT patients (n = 129) showed higher serum levels of melatonin (p = 0.001) and total antioxidant capacity (p = 0.001) and lower serum levels of malondialheyde (p = 0.01) than non-surviving LT patients (n = 16). Logistic regression analysis showed that high serum melatonin levels prior to LT were associated with lower one-year LT mortality (odds ratio = 0.525; 95% confidence interval (CI) = 0.331–0.834; p = 0.006). We found an association between serum levels of melatonin with serum levels of malondialheyde (rho = −0.22; p = 0.01) and total antioxidant capacity (rho = 0.21; p = 0.01). Thus, the novel findings of our study were the association between high serum melatonin levels prior to LT and survival at first year after LT and the association between serum levels of melatonin with malondialheyde and total antioxidant capacity.

A study of Canada geese, Branta canadensis, nesting on islands in southeastern Alberta

1970 ◽  
Vol 48 (2) ◽  
pp. 235-240 ◽  
Author(s):  
Kees Vermeer
Keyword(s):  
Egg Laying ◽  
Water Levels ◽  
Branta Canadensis ◽  
Canada Goose ◽  
Canada Geese ◽  
Uniform Spacing ◽  
Incubation Periods

Canada goose clutches situated on islands in Dowling Lake and Lake Newell, Alberta, were checked from laying to hatching. Egg-laying intervals averaged 1.87 days and incubation periods 26.8 days. The distribution of nests showed a significant deviation from randomness in the direction of uniform spacing. Causes of extensive hatching failure at Dowling Lake were predation and desertion. Predation by coyotes was facilitated by low water levels. A preference for nesting on islands appears to be a mechanism to counteract mammalian predation.

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