Annual profiles of blood packed cell volumes of captive American kestrels

1983 ◽  
Vol 61 (11) ◽  
pp. 2550-2555 ◽  
Author(s):  
Nancy B. Rehder ◽  
David M. Bird
Keyword(s):  
Body Weight ◽  
Ambient Temperature ◽  
Air Temperature ◽  
Egg Laying ◽  
Falco Sparverius ◽  
Photoperiodic Control ◽  
American Kestrels ◽  
Males And Females ◽  
Cell Volumes

Mean hematocrits of 20 pairs of captive American kestrels (Falco sparverius) sampled from November 1980 to September 1981 fell significantly (p < 0.0001) from winter maxima of 47.9% for females and 50.9% for males to summer minima of 29.1% for females and 30.1% for males. It is suggested that ambient temperature, reproduction, and molt influence the photoperiodic control of avian hematocrit. Mean hematocrits declined 1–2 months before the onset of molt or egg laying (whichever came first for females) and increased at the termination of molt for nonlaying females only. During nonreproductive and nonmolting states, hematocrits varied indirectly and logarithmically with air temperature (r2♂+♀ = 0.74) and directly and linearly with body weight (r2♂ = 0.91, r2♀ = 0.95). Total mean packed cell volumes of males and females were not significantly different.

Nutrient Reserve Dynamics of Breeding and Molting Brant

The Auk ◽  
1984 ◽  
Vol 101 (2) ◽  
pp. 361-370 ◽  
Author(s):  
C. Davison Ankney
Keyword(s):  
Body Weight ◽  
Northwest Territories ◽  
Egg Production ◽  
Muscle Protein ◽  
Nutritional Stress ◽  
Egg Laying ◽  
Branta Bernicla ◽  
Nutrient Reserve ◽  
Males And Females ◽  
Nutrient Reserves

Abstract I collected 150 Brant (Branta bernicla) at East Bay, Southampton Island, Northwest Territories, Canada, in 1979 and 1980 to evaluate how much these birds rely on reserves of fat, protein, and calcium during egg production, incubation, and the subsequent wing molt. Egg laying resulted in decreases in body weight and nutrient reserves of females. These decreases could have accounted for all of the fat but only 70% of the protein in an average clutch. Neither males nor females had sufficient reserves when incubation began to enable them to fast during that period. Only 11% and 22% of the energy required by males and females, respectively, could have been derived from their reserves during incubation. Brant evidently did not use body reserves to obtain nutrients for feather growth during wing molt. Rather, molting males and females accumulated muscle protein, which supports my hypothesis that wing molt is not a nutritional stress for waterfowl.

Total plasma protein level as an indicator of condition in wild American kestrels (Falco sparverius)

1997 ◽  
Vol 75 (5) ◽  
pp. 680-686 ◽  
Author(s):  
Russell D. Dawson ◽  
Gary R. Bortolotti
Keyword(s):  
Plasma Protein ◽  
Protein Level ◽  
Egg Laying ◽  
Falco Sparverius ◽  
Total Plasma ◽  
Protein Levels ◽  
American Kestrels ◽  
Total Plasma Protein ◽  
In The Wild ◽  
Plasma Protein Level

Total plasma protein levels were determined for 292 female and 228 male American kestrels (Falco sparverius) in the wild. Plasma protein levels were significantly higher in females than in males, and higher during prelaying than during incubation. For both sexes, plasma protein levels did not vary significantly with the number of days before or after egg laying on which the sample was taken, time of sampling, prey abundance, age, molt, or infection by the blood parasite Haemoproteus sp. Protein levels in females increased with date of sampling and body condition during prelaying, while the same pattern was seen in males during incubation. With the exception of those of prelaying females, plasma protein levels increased with ambient temperature. The results of this study suggest that at least some of the variation observed in total protein levels is attributable to physical condition. However, further investigation is required before the reliability of using total plasma protein level as a tool to assess the health and condition of kestrels is known.

The effect of Trichinella pseudospiralis infection on the reproductive success of captive American kestrels (Falco sparverius)

1986 ◽  
Vol 64 (10) ◽  
pp. 2123-2125 ◽  
Author(s):  
Michèle D. Saumier ◽  
Manfred E. Rau ◽  
David M. Bird
Keyword(s):  
Reproductive Success ◽  
Egg Laying ◽  
Falco Sparverius ◽  
Embryo Mortality ◽  
Trichinella Pseudospiralis ◽  
Delayed Onset ◽  
American Kestrels ◽  
Do So

Trichinella pseudospiralis infections reduced the reproductive success of captive American kestrels (Falco sparverius). Infected birds manifested a delayed onset of egg laying (day 31) when compared with uninfected controls (day 23). All control females continued to produce eggs after the first three were removed, but only 66.7% of the infected females managed to do so. Consequently, infected birds produced a mean total of only 4.9 eggs, as compared with 7.1 eggs for the controls. Breakage (29.0%) and embryo mortality (40.0%) were the major sources of egg loss among infected birds. The corresponding losses among control birds were 1.6 and 4.7%, respectively. Consequently, control birds produced an average of 2.1 hatchlings per pair, whereas infected birds produced only 0.6.

scholarly journals Interrelationships of body weight and bone weight with densitometric properties of tibiotarsal bone in geese during post-hatching development

2017 ◽  
Vol 60 (No. 12) ◽  
pp. 682-690
Author(s):  
A. Charuta ◽  
MR Tatara ◽  
M. Dzierzecka ◽  
E. Polawska ◽  
I. Ptaszynska-Sarosiek
Keyword(s):  
Computed Tomography ◽  
Body Weight ◽  
Correlation Coefficient ◽  
Quantitative Computed Tomography ◽  
Peripheral Quantitative Computed Tomography ◽  
Dual Energy ◽  
X Ray ◽  
Males And Females ◽  
Different Parts

The aim of this study was to evaluate interrelationships of body weight and bone weight and densitometric properties of the tibiotarsus in White Koluda Geese (W31) in the post-hatching period. The study was performed using dual-energy X-ray absorptiometry (DEXA) and peripheral quantitative computed tomography (pQCT) at two different parts of tibia: proximal metaphysis and mid-diaphysis. The investigation was performed on 100 bones obtained from males and females at the age of 1, 14, 28, 42 and 56 days of life. All the calculations were performed using the Statistica 9.0 software (StatSoft, Inc. Tulsa, USA). Pearson&rsquo;s correlation coefficient of body weight and bone weight with all the investigated variables of bone was determined. Depending on the method used for densitometric measurements &ndash; DEXA or pQCT, the current study has revealed significant differences in the number of correlations of bone weight and body weight with the evaluated densitometric parameters. Sex-related differences in the investigated interrelationships were also found. In the case of proximal epiphysis, negative correlations of vBMD, tBMC, CTR_DEN and CRT_CNT with body weight and bone weight dominated in one-day-old males. Based on the current observations and the negative correlations of body weight and vBMD, CRT_DEN and TRAB_DEN obtained in the mid-diaphysis of tibiotarsus at the age of 14 days of life, it was concluded that this bone is much more prone to deformations and fractures in males than in females.

Reproductive changes in American kestrels (Falco sparverius) in relation to exposure to technical hexabromocyclododecane flame retardant

2011 ◽  
Vol 30 (11) ◽  
pp. 2570-2575 ◽  
Author(s):  
Kim J. Fernie ◽  
Sarah C. Marteinson ◽  
David M. Bird ◽  
Ian J. Ritchie ◽  
Robert J. Letcher
Keyword(s):  
Flame Retardant ◽  
Falco Sparverius ◽  
American Kestrels

scholarly journals From individual to population level: Temperature and snow cover modulate fledging success through breeding phenology in greylag geese (Anser anser)

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Didone Frigerio ◽  
Petra Sumasgutner ◽  
Kurt Kotrschal ◽  
Sonia Kleindorfer ◽  
Josef Hemetsberger
Keyword(s):  
Ambient Temperature ◽  
Reproductive Output ◽  
Population Level ◽  
Egg Laying ◽  
Future Research ◽  
Breeding Phenology ◽  
Anser Anser ◽  
Fledging Success ◽  
Average Annual Temperature ◽  
Greylag Geese

AbstractLocal weather conditions may be used as environmental cues by animals to optimize their breeding behaviour, and could be affected by climate change. We measured associations between climate, breeding phenology, and reproductive output in greylag geese (Anser anser) across 29 years (1990–2018). The birds are individually marked, which allows accurate long-term monitoring of life-history parameters for all pairs within the flock. We had three aims: (1) identify climate patterns at a local scale in Upper Austria, (2) measure the association between climate and greylag goose breeding phenology, and (3) measure the relationship between climate and both clutch size and fledging success. Ambient temperature increased 2 °C across the 29-years study period, and higher winter temperature was associated with earlier onset of egg-laying. Using the hatch-fledge ratio, average annual temperature was the strongest predictor for the proportion of fledged goslings per season. There is evidence for an optimum time window for egg-laying (the earliest and latest eggs laid had the lowest fledging success). These findings broaden our understanding of environmental effects and population-level shifts which could be associated with increased ambient temperature and can thus inform future research about the ecological consequences of climate changes and reproductive output in avian systems.

Toe Temperatures During Dartmoor Training

1988 ◽  
Vol 74 (3) ◽  
pp. 181-186
Author(s):  
S. P. L. Travis
Keyword(s):  
Surface Temperature ◽  
Ambient Temperature ◽  
Skin Temperature ◽  
Air Temperature ◽  
Factors Associated ◽  
Recording Period ◽  
Exposure To Cold ◽  
Main Factors ◽  
Minimum Air Temperature

AbstractThe surface temperature of eight Royal Marine recruits was monitored in the field during Autumn training on Dartmoor (minimum air temperature 4.5°C). The lowest skin temperature recorded was 6.1°C. One subject experienced a toe temperature below 10° for 5.5 hours and below 15°C for 12.6 hours during a 24 hour recording period. Ambient temperature and inactivity during exposure to cold were the main factors associated with low toe temperatures but individual responses varied widely.

Effect of Changes in Ambient Temperature on Spontaneous Activity, Food Intake and Body Weight of Goldthioglucose-Obese and Nonobese Mice

1957 ◽  
Vol 188 (3) ◽  
pp. 435-438 ◽  
Author(s):  
M. J. Fregly ◽  
N. B. Marshall ◽  
J. Mayer
Keyword(s):  
Body Weight ◽  
Food Intake ◽  
Ambient Temperature ◽  
The Body ◽  
Lower Body ◽  
Obese Mice ◽  
Ambient Temperatures ◽  
Exposure To Cold ◽  
Running Activity ◽  
Body Weights

Goldthioglucose-obese mice cannot adjust their food intake to meet the increased energy requirements due to cold. At all ambient temperatures above 15°C the spontaneous running activity of these animals is less than that observed for nonobese controls. Activity of obese mice is maximal at 19°C and minimal at 15°C or lower. Body weights decrease during exposure to cold. In contrast to that of obese mice, running activity of nonobese controls is maximal at an ambient temperature of 25°C but nearly ceases at 15°C or lower. The food intake of these animals increases in the cold and remains elevated even at temperatures at which activity decreases. The body weight of nonobese controls is either maintained constant or increases during exposure to cold air.

scholarly journals Influence of gender on carcass yield of twin lambs Blackbelly x Pelibuey at 56 days of age

2016 ◽  
Vol 68 (4) ◽  
pp. 1077-1084
Author(s):  
I. del C. García-Osorio ◽  
J. Oliva-Hernández ◽  
M.M. Osorio-Arce ◽  
G. Torres-Hernández ◽  
J. A. Hinojosa-Cuéllar ◽  
...  
Keyword(s):  
Body Weight ◽  
Weight Gain ◽  
Growth Yield ◽  
Daily Weight Gain ◽  
Longissimus Dorsi ◽  
Average Daily Weight Gain ◽  
Carcass Yield ◽  
Longissimus Dorsi Muscle ◽  
Dorsi Muscle ◽  
Males And Females

ABSTRACT The aim of this study was to determine the influence of gender on pre-weaning growth, yield and weight of primal cuts of the carcass of Blackbelly x Pelibuey lambs. 16 twin lambs were used. The lamb gender was the fixed factor. The variables evaluated were: body weight at birth and at weaning, average daily weight gain, weight and yield of carcass and primal cuts: neck, arm, thorax, abdomen and leg. Gender did not affect (P>0.05) body weight at birth. However, the pre-weaning average daily weight gain and body weight at weaning were affected (P<0.05) by the gender. Hot carcass yield and weight and primal cuts were not affected (P>0.05) by the gender of the lamb. Nevertheless, the area of the Longissimus dorsi muscle and cavity fat were different between males and females (P<0.05) 11.5±0.73cm2 and 198±0.05 g vs 9.3±0.73cm2 and 282±0.05g, respectively. In conclusion, in twin lambs Blackbelly x Pelibuey males had greater average daily weight gain and body weight at weaning than females. Carcass yield and weight and primal cuts were not affected by the gender of the lamb. However, males had greater area of the L. dorsi muscle than females and these in turn had a greater amount of cavity fat than males.

The influence of Trichinella pseudospiralis infection on the behaviour of captive, nonbreeding American kestrels (Falco sparverius)

1988 ◽  
Vol 66 (7) ◽  
pp. 1685-1692 ◽  
Author(s):  
Michèle D. Saumier ◽  
Manfred E. Rau ◽  
David M. Bird
Keyword(s):  
Falco Sparverius ◽  
Competitive Fitness ◽  
American Kestrel ◽  
Behavioural Changes ◽  
Trichinella Pseudospiralis ◽  
Behavioural Effects ◽  
American Kestrels ◽  
Muscle Larvae ◽  
Adult Phase ◽  
Muscle Groups

Trichinella pseudospiralis infections induced mild behavioural changes in the American kestrel host (Falco sparverius) within the first 5 days postinoculation, a period that corresponds to the adult phase of the infection. However, more severe effects on mobility were precipitated as the larvae migrated and became established in the musculature. The debilitation persisted for at least 5 weeks postinoculation and involved a reduction in exercising, flying, elevated perching, and preening, and was accompanied by an increase in the frequency of walking and floor perching. Such behavioural effects, attributable to the presence of muscle larvae, may reduce the competitive fitness of infected individuals. The muscle larvae were randomly distributed among various muscle groups.

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