Food availability and primary feather molt in European starlings, Sturnus vulgaris

1997 ◽  
Vol 75 (6) ◽  
pp. 948-953 ◽  
Author(s):  
John P. Swaddle ◽  
Mark S. Witter
Keyword(s):  
Food Availability ◽  
Food Deprivation ◽  
Growth Rates ◽  
Sturnus Vulgaris ◽  
European Starlings ◽  
Primary Feather ◽  
Feather Growth ◽  
Feather Molt ◽  
Experimental Treatments ◽  
And Control

The effects of food quality and overall food intake on molt have been experimentally investigated in a number of species. However, little is known concerning the influence of periodic food availability on molt parameters, although there are some associations in the field. In this study, we experimentally manipulated food availability through food deprivation during the molt of adult and juvenile European starlings, Sturnus vulgaris. By monitoring molt scores, wingtip shape, and lengths and length asymmetries of primary feathers during molt, we demonstrated that food deprivation can influence molt. Food-deprived juvenile starlings exhibited slower feather growth rates, although the duration and rate of molt were not affected. There were no differences in wingtip shape between food-deprived and control birds at the end of molt for either adults or juveniles. We also observed erratic reshedding of previously molted primary feathers in juveniles, although this did not appear to be related to the experimental treatments. The results of this study imply that feather growth rates and shedding rates are differentially affected by food availability: growth rates may be decreased when food deprivation occurs, whereas shedding rates are relatively unaffected.

The effects of molt on the flight performance, body mass, and behavior of European starlings (Sturnus vulgaris): an experimental approach

1997 ◽  
Vol 75 (7) ◽  
pp. 1135-1146 ◽  
Author(s):  
John P. Swaddle ◽  
Mark S. Witter
Keyword(s):  
Body Mass ◽  
Experimental Approach ◽  
Sturnus Vulgaris ◽  
Flight Performance ◽  
European Starlings ◽  
Reduced Body ◽  
Body Mass Regulation ◽  
Behavioral Parameters ◽  
Feather Molt ◽  
And Behavior

The physiological and energy costs of avian molt are well documented, but indirect consequences such as changes in flight performance have received less attention. Here, we report two experiments that investigated flight performance, body mass regulation, and behavior in captive starlings (Sturnus vulgaris). In the first experiment, we found a U-shaped change in take-off escape performance during natural molt: birds ascended at the shallowest trajectories during midmolt. Birds' body mass was also reduced during molt. In the second experiment, we manipulated the plumage of starlings to simulate different stages of flight-feather molt. This allowed us to separate the aerodynamic costs of feather loss from the physiological costs of feather synthesis normally associated with plumage growth. Through observations of flight (take-off, aerial maneuverability, and level flapping-flight speed) and behavioral parameters, we demonstrated that birds in simulated molt have reduced flight performance and reduced body mass. These birds also decrease the time spent performing energetically costly activities and seek areas of relative protection. In the longer term, some aspects of performance return to pretreatment levels, implying compensation for the plumage manipulations. Our results demonstrate that molt incurs significant functional costs that may play an important role in the adaptive radiation of molt strategies and molt patterns observed in avian species.

scholarly journals Body Weight and Feather Growth of Male Barrow's Goldeneye During Wing Molt

The Condor ◽  
2000 ◽  
Vol 102 (1) ◽  
pp. 228-231
Author(s):  
Debbie van de Wetering ◽  
Fred Cooke
Keyword(s):  
Body Weight ◽  
Growth Rates ◽  
Adult Males ◽  
Primary Feather ◽  
Body Reserves ◽  
Feather Growth ◽  
Bucephala Islandica ◽  
Daily Change ◽  
The Mean

Abstract We studied the timing, duration, and rate of wing molt of male Barrow's Goldeneye (Bucephala islandica). The mean daily change in primary feather length was 2.6%, which is consistent with rates reported for other waterfowl species. The mean length of the flightless period was 31 days (range: 27–34 days), excluding the pre-shedding interval. Wing molt extended from early July to mid-September. Peak wing molt occurred between 20 July and 23 August. The mean body weight of adult males decreased significantly during wing molt. Heavier birds had greater remigial growth rates and experienced more substantial declines in body weight than lighter birds, suggesting that body reserves may be used to increase the rate of remigial growth.

scholarly journals Describing the growth and molt of modern domestic turkey (Meleagris gallopavo) primary wing feathers

2020 ◽  
Vol 98 (12) ◽  
Author(s):  
Emily M Leishman ◽  
Nienke van Staaveren ◽  
Don R McIntyre ◽  
Jeff Mohr ◽  
Benjamin J Wood ◽  
...  
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Mixed Models ◽  
Generalized Linear Mixed Models ◽  
Linear Mixed Models ◽  
Meleagris Gallopavo ◽  
Primary Feather ◽  
Feather Growth ◽  
Significant Difference ◽  
Over Time

Abstract The use of feathers as noninvasive physiological measurements of biomarkers in poultry research is expanding. Feather molting patterns and growth rates, however, are not well described in domestic poultry. These parameters could influence the measurement of these biomarkers. Therefore, the objective of this study was to describe the juvenile primary feather molting patterns and feather growth rates for domestic turkeys. The 10 primary wing feathers of 48 female turkeys were measured weekly from week 1 (0 d of age) to week 20. Feathers were manually measured, and the presence or absence of each primary feather was recorded weekly. Generalized linear mixed models were used to investigate if feather growth differed between the primary feathers. The molting of the juvenile primary feathers followed a typical descending pattern starting with P1 (5 wk of age), while P9 and P10 had not molted by the end of the study (20 wk of age). The average feather growth rate was 2.4 cm/wk, although there was a significant difference between the 10 primary feathers (P < 0.0001, 2.1 to 2.8 cm/wk). Over time, feather growth followed a pattern where the growth rate reaches a peak and then declines until the feather is molted. The results of this study provide a critical update of patterns of molting and feather growth in primary wing feathers of modern turkeys. This can have implications for the interpretation of physiological biomarkers, such as the longitudinal deposition of corticosterone, in the feathers of domestic turkeys.

Bacteriophages reduce Escherichia coli O157:H7 levels in experimentally inoculated sheep

2009 ◽  
Vol 89 (2) ◽  
pp. 285-293 ◽  
Author(s):  
S J Bach ◽  
R P Johnson ◽  
K. Stanford ◽  
T A McAllister
Keyword(s):  
Escherichia Coli ◽  
Oral Administration ◽  
Coliform Bacteria ◽  
Escherichia Coli O157 ◽  
Fecal Shedding ◽  
Total Coliforms ◽  
E Coli ◽  
Oral Inoculation ◽  
Experimental Treatments ◽  
And Control

Bacteriophage biocontrol has potential as a means of mitigating the prevalence of Escherichia coli O157:H7 in ruminants. The efficacy of oral administration of bacteriophages for reducing fecal shedding of E. coli O157:H7 by sheep was evaluated using 20 Canadian Arcott rams (50.0 ± 3.0) housed in four rooms (n = 5) in a contained facility. The rams had ad libitum access to drinking water and a pelleted barley-based total mixed ration, delivered once daily. Experimental treatments consisted of administration of E. coli O157:H7 (O157), E. coli O157:H7+bacteriophages (O157+phage), bacteriophages (phage), and control (CON). Oral inoculation of the rams with 109 CFU of a mixture of four nalidixic acid-resistant strains of E. coli O157:H7 was performed on day 0. A mixture of 1010 PFU of bacteriophages P5, P8 and P11 was administered on days -2, -1, 0, 6 and 7. Fecal samples collected on 14 occasions over 21 d were analyzed for E. coli O157:H7, total E. coli, total coliforms and bacteriophages. Sheep in treatment O157+phage shed fewer (P < 0.05) E. coli O157:H7 than did sheep in treatment O157. Populations of total coliforms and total E. coli were similar (P < 0.05) among treatments, implying that bacteriophage lysis of non-target E. coli and coliform bacteria in the gastrointestinal tract did not occur. Bacteriophage numbers declined rapidly over 21 d, which likely reduced the chance of collision between bacteria and bacteriophage. Oral administration of bacteriophages reduced shedding of E. coli O157:H7 by sheep, but a delivery system that would protect bacteriophages during passage through the intestine may increase the effectiveness of this strategy as well as allow phage to be administered in the feed.Key words: Escherichia coli O157:H7, bacteriophage, sheep, environment, coliforms

PRE-MATERNAL ISOLATION EFFECTS ON BEHAVIOUR AND ENDOCRINE FUNCTION OF OFFSPRING

1969 ◽  
Vol 62 (2) ◽  
pp. 367-384 ◽  
Author(s):  
A. M. Sackler ◽  
A. S. Weltman ◽  
R. Schwartz ◽  
P. Steinglass
Keyword(s):  
Locomotor Activity ◽  
Growth Rates ◽  
Female Offspring ◽  
The Body ◽  
Endocrine Function ◽  
Male And Female ◽  
Isolation Stress ◽  
Developmental Growth ◽  
Body Weights ◽  
And Control

ABSTRACT This report was designed to determine combined effects of maternal endocrine imbalances and abnormal behaviour due to prolonged isolation stress of female mice on the behaviour, developmental growth rate and endocrine function of their offspring. Sixty female albino mice averaging 19 g were divided equally into isolated and control groups. The isolated females were housed singly; control females were maintained in groups of 2 mice per cage. After observation of behavioural and physiological effects characteristic of isolation stress in the test mice, all isolated and control mice were mated after a 6½ month experimental, isolation period. No differences were observed in fertility and fecundity of the two groups of mothers. Analyses of developmental growth rates of the litters of the isolated versus control mothers showed significantly lower body weights in the test offspring at 3 and 4 weeks of age. The body weights of the female offspring remained significantly lower from the 4th to 11th weeks. The effects on the body weights of the male offspring declined and were no longer statistically significant at the 5th to 11 weeks. Locomotor activity at 4½ and 8 weeks of age was markedly or significantly higher in the male and female mice from isolated mothers. Tail-blood samples taken prior to autopsy at 5 and 11 weeks of age revealed significant decreases in the total leukocyte and eosinophil counts of both sexes. At the two ages, the absolute and relative spleen and thymus weights of the male and female offspring were markedly and/or significantly lower than the values observed in counterpart young from control females. Significant decreases were also observed in the absolute gonadal organ weights of both sexes at 11 weeks of age. The various data indicated inhibited growth rates, heightened locomotor activity and evasiveness, as well as evidence of increased adrenocortical function in the offspring from test mothers. The gonadal weight decreases suggested retarded gonadal development. Further studies using split-litter techniques are required to differentiate the effects of prenatal endocrine imbalances versus postnatal maternal influence (i. e., nursing care) on the offspring.

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