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Genetic improvement of skeletal architecture and locomotion in domestic poultryDuggan, Brendan Michael January 2018 (has links)
Breeding success in the broiler chicken has been accompanied by gait problems which are detrimental to productivity and welfare. Although these gait issues have not been reported to the same extent in Pekin ducks, there is concern that such problems will manifest if the duck continues on its current selection trajectory. In order to understand how changes in morphology due to selection have affected gait in both species, divergent lines were objectively assessed for gait using a pressure platform (12 birds per line at three, five and seven weeks of age). The broiler chicken was compared to the slower growing layer chicken and the Pekin duck to its slower growing ancestor, the mallard. Two breeding lines of Pekin duck were also assessed. After gait assessment, the leg bones (femur and tibiotarsus) were scanned by computed tomography to measure morphological changes which have occurred due to selection for high growth and meat yield. Results were analysed by ANOVA, accounting for age and sex. During walking, heavy lines walked at a slower velocity, displayed a wider stance and spent more time supporting their mass on both feet than their lighter conspecifics, strategies which are likely to improve balance. The foot angle while walking differed between lines; all duck lines rotated their feet internally whereas the layer chickens’ feet were aligned with the direction of travel. Conversely the broiler chicken rotated its feet externally by seven weeks of age. Morphologically, the main differences were between species. Duck lines reached adult leg size earlier than chickens, which may be a response to differing adaptive environments prior to domestication. This early cessation of bone growth in ducks may provide more opportunity for the bones to remodel to handle the loads imposed on them. Lower levels of porosity and a unique cortical architecture observed in ducks endow relatively greater bone strength. Bone curvature also differed between species; the tibiotarsus curved more laterally in ducks than in chickens and may be a swimming adaptation that hinders locomotion on land in the modern production bird. In order to improve the objectivity of selection for better gait in poultry, the genetic parameters of gait components selected on the basis of results in this thesis were estimated using a linear mixed model in a population of Pekin ducks of known pedigree. As they are a simpler measure, similar or improved heritability estimates were estimated for these gait components when compared with the standard commercial gait score which is based on a subjective view of walking ability. Intense selection for economic traits has altered gait in similar ways in both species. To improve gait in poultry, greater breeding success may be achieved by focussing on those components of gait which have changed through selection, rather than using a subjective overall visual gait score. Furthermore, in both species, adaptations for pre-domesticated life may have affected the ability with which the selected lines have accommodated their gait to other morphological changes associated with increasing body mass.
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Injurious pecking behavior of Pekin ducks on commercial farms: characteristics, development and duck welfareYiru Dong (8086220) 05 December 2019 (has links)
<p></p><p>Injurious pecking is one of the major
welfare concerns for poultry and other captive birds. Injurious pecking
behavior can result in welfare problems including feather and skin damage,
pain, substantial heat loss because of feather loss, and even death of the
recipient bird. Injurious pecking can also cause economic losses because of
reduced production efficiency, increased mortality and reduced feed conversion
ratio. Injurious pecking behavior includes feather pecking, feather picking,
cannibalism and aggressive pecking. Feather pecking, when a bird uses its beak
or bill to peck at the feathers of another bird, can be categorized as either
gentle feather pecking (repeated and light pecks) or severe feather pecking
(singular and hard pecks). Feather picking is described as a self-damaging
behavior that occurs in psittacine species such as parrots and also in ducks.
Cannibalism is classified as either tissue pecking (persistently forceful pecks
directed at exposed skin) or vent pecking (pecks directed at the top of cloaca
or below the cloaca). Unlike feather pecking, feather picking and cannibalism,
which are not associated with aggression, aggressive pecking establishes and
maintains the dominance hierarchy. Limited studies have examined injurious
pecking of Pekin ducks, but results from previous research examining duck
picking behavior and feather quality suggested that ducks pick mostly at
themselves and that the development of picking is related to feather growth and
worsens with age. Scant information is available regarding the prevalence of
injurious pecking behavior and characteristics of the behavior. </p>
<p> </p>
<p>To address some of the gaps in the
knowledge regarding injurious pecking behavior of ducks, this study examined 1)
age-related changes in frequencies and durations of preening behavior and
injurious pecking behavior of Pekin ducks, including self-picking and feather
pecking; 2) the body locations most frequently affected, and whether feather
removal and feather eating occurred concurrently with injurious pecking; 3) the
prevalence of injurious pecking behavior; and 4) age-related changes in duck
welfare that may be associated with injurious pecking. Information about
preening behavior was recorded because injurious pecking and preening behavior
may have similar age-related patterns, as previous studies have suggested that
increased levels of preening behavior are related to feather growth.</p>
<p>Data were collected on 5 commercial duck
flocks on 5 farms. Welfare data were collected from all 5 flocks and behavior
data were collected from 2 of the 5 flocks. For the two flocks, duck behavior
was video-recorded over two consecutive days at 20-22d (Period 1), 27-29 d
(Period 2), and 34-36 d (Period 3). Scan sampling and focal animal sampling
were used to analyze the video recordings and determine the frequencies and
durations of injurious pecking behavior (gentle feather pecking, severe feather
pecking, self-picking and aggressive pecking). For scan sampling, the
percentage of ducks performing injurious pecking behavior were recorded every
30 min from 0900h to 1500h. For both scan and focal animal sampling, the
viewing area of each camera installed in the barn was divided into eight equal
squares (observation areas), of which four were randomly selected for analysis.
For focal animal sampling, one duck was randomly selected from each observation
area and observed for 30 min from 0945h to 1015h and 1345h to 1415h ((n=8 ducks
per camera (4 ducks in the morning and 4 ducks in the afternoon) and n=24 ducks
per barn)) to determine the duration and frequency of injurious pecking
behavior and preening behavior. For all five flocks, duck welfare (feather
quality, feather cleanliness, nostril cleanliness, eye condition, footpad
condition and gait) was assessed in 100 ducks from each flock between 17-18 d
(Period 1), 29-30 d (Period 2), and 36-37 d (Period 3). Welfare data and
frequencies of behaviors from focal animal sampling were analyzed using the
GLIMMIX procedure (SAS 9.4). Scan animal sampling data and behavioral durations
from focal animal sampling data were analyzed using the MIXED procedure (SAS
9.4). </p>
<p> </p>
<p>The most frequently observed form of
injurious pecking behavior was gentle feather pecking, which increased from
Period 1 to Period 2 (P < 0.001), then declined from Period 2 to Period 3 (P
< 0.001). Gentle feather pecking was most frequently directed at the tail,
wings and back. Removal of feathers was observed 13 times, and feathers were
eaten 7 times in the 6 days of video observation. Ducks’ eye condition, feather
cleanliness under the tail, and feather quality on all the assessed body
locations, except for the neck, worsened with age. Age was a major factor
affecting the development of injurious pecking behavior including the
proportion of ducks performing gentle feather pecking behavior (P < 0.001),
frequency and duration of gentle feather pecking behavior (frequency: P < 0.001;
duration: P < 0.001), and other injurious pecking behavior (frequency: P = 0.038;
duration: P = 0.036). From scan sampling, 1.85% of the ducks were observed
performing severe feather pecking behavior, 6.84% of the ducks were observed
performing aggressive pecking behavior, and no duck was observed performing
self-picking behavior in the total of 1082 ducks performing injurious pecking
behavior across the 3 periods. From focal sampling, 83.33% of the ducks were
observed performing gentle feather pecking behavior, 13.89% of the ducks were
observed performing severe feather pecking behavior, 16.67% of the ducks were
observed performing aggressive pecking behavior, and only 1.39% of the ducks
were observed performing self-picking behavior of the total of 288 ducks
observed. Frequency and duration of preening behavior increased from Period 1
to Period 2 (frequency: P = 0.004; duration: P < 0.001), then declined from
Period 2 to Period 3 (frequency: P < 0.001; duration: P < 0.001). </p>
<p> </p>
<p>In conclusion, feather pecking between
conspecifics was the most frequently performed pecking behavior of commercial
Pekin ducks. Age was a major factor affecting the development of pecking
behavior, which peaked at 27-29 d. The body locations that injurious pecking
behaviors were most frequently directed at were the tail, wings and back,
consistent with the welfare condition results that indicated a worsening tail,
wing and back feather quality with age. Feather removal and feather eating were
infrequently observed, which might indicate that injurious pecking behavior in
Pekin ducks is not for the purpose of pulling out and eating the feathers. The
frequency and duration of gentle feather pecking and preening behavior followed
a similar pattern with age; however, further research is needed to evaluate
whether these behaviors are associated. This study provided more details about age-related
changes in injurious pecking behavior and welfare of commercial Pekin ducks. However,
further work is needed to investigate specific causes of and methods to reduce
injurious pecking behavior of Pekin ducks.</p>
<p> </p><br><p></p>
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PHENOTYPIC AND GENETIC ANALYSIS OF PERFORMANCE AND WELFARE TRAITS IN PEKIN DUCKSCarl Kroger (17594145) 12 December 2023 (has links)
<p dir="ltr">The White Pekin duck (<i>Anas platyrhynchos domesticus</i>) is the most widely consumed duck protein in the world. Total duck meat production had a global annual increase of 2.1% per year from 2010 to 2019. The increase in duck meat production can be credited to improved management strategies, nutritional programs, and genetic improvement made to the Pekin ducks by structured breeding programs. Regardless of the advancements already achieved by Pekin duck breeding programs, improvements can still be made. One such improvement that can be made in Pekin duck populations is reducing the frequency of the emerging welfare concern known as flip-over (FO). We hypothesize that egg quality traits, wingspan, back length, and hip width are genetically influenced and their inclusion into Pekin duck breeding programs can be used to improve the Pekin duck. Egg quality traits were collected at weeks of age 30, 32, 35 and 40 on two generations of Pekin duck hens. All heritability estimates and Genetic correlations were calculated using BLUPF90 software, the Restricted Maximum Likelihood (REML) method, and 9,418 individuals in the pedigree. All egg quality traits evaluated are moderate to highly heritable ranging from 0.23 for egg shape to 0.70 for shell ratio. Two hatches of 1,200 Pekin duck hens were assessed at day of age 23 and 30 for wingspan, hip width, and back length using image analysis. Wingspan, hip width, and back length were found to be heritable ranging from 0.04 ± 0.013 to 0.27 ± 0.025 for hip width and back length respectfully. This thesis will discuss approaches to evaluating genetic parameters of egg quality traits in hatching eggs and the possibility of reducing FO through the selection of increased wingspan length.</p>
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Effect of embryonic thermal manipulation on heat shock protein 70 (HSP70) during an acute inflammatory stress in Pekin ducklings and turkey poults post-hatchShanmugasundaram, Revathi 10 August 2018 (has links)
No description available.
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Etude de la composition du microbiote intestinal des canards. Impact du gavage, de l’ajout d’un probiotique (Lactobacillus sakei) et d’un composé organométallique (cadmium) / Study of ducks intestinal microbiota composition. Impact of overfeeding, addition of a probiotic (Lactobacillus sakei) and an organometallic compound (cadmium)Vasai, Florian 12 December 2013 (has links)
Le microbiote intestinal constitue un élément important pour l’hôte, il est impliqué notamment au niveau immunologique ou physiologique. La connaissance de la composition de ce microbiote est la première étape dans la compréhension des phénomènes qui lui sont associés. Les travaux de cette thèse se sont articulés selon plusieurs objectifs. La première étape a été de faire un état des lieux de la composition du microbiote de deux types génétiques parentaux : le canard Pékin (Anas Platyrhynchos), le canard de Barbarie (Cairina Moschata) ainsi que de leur hybride ; le canard mulard. Nous avons ainsi pu observer des compositions différentes selon le type génétique avec tout de même la prédominance dans chacune des trois espèces de deux phyla : les Firmicutes et les Bacteroidetes. Différentes conditions rencontrées dans l’environnement sont à même de créer un déséquilibre dans la composition du microbiote. Une des conditions possibles est un changement dans l’alimentation ainsi la seconde étape a été de voir l’impact du gavage sur les communautés bactériennes composant le microbiote. Celui-ci induit bien des modifications au sein du microbiote en privilégiant certaines classes bactériennes notamment les Bacilli et les Clostridia selon le type génétique. Un effet du gavage a été montré au niveau du microbiote iléal tandis que l’on retrouve un effet du type génétique ainsi que du gavage mais plus faible que dans l’iléon au niveau des caeca. Deux autres travaux ont été réalisés, le premier concernait l’ajout d’un probiotique (Lactobacillus sakei) sur le microbiote des canards mulards durant la phase de gavage. Nous avons montré que lors de cet ajout, nous observions une forte augmentation des lactobacilli au niveau de l’iléon. Enfin suite aux fortes contaminations retrouvées dans le sud-ouest ainsi que ses effets toxiques montrés dans différentes études, le dernier travail effectué a été de voir l’effet du cadmium sur le microbiote des canards Pékin et Barbarie. Nous avons pu ainsi observer les modifications de la communauté microbienne lors de l’ajout de cadmium ainsi l’accumulation de celui-ci dans les reins au cours du gavage. Des effets combinés entre le cadmium et la période de gavage ainsi qu’avec le type génétique ont été mis en lumière. Une tendance à une accumulation différentielle du cadmium a été observé selon le type génétique. / The intestinal microbiota is an important element for the host; it is particularly involved in immunological or physiological level. Knowledge of the composition of the microbiota is the first step in understanding the phenomena associated with it. The work of this PhD was organized according to several objectives. The first step was to realize a molecular inventory of the microbiota composition of the two parental genetic types: the Pekin duck (Anas Platyrhynchos), the Muscovy duck (Cairina moschata) and their hybrid, the mule duck. We have observed different compositions depending on the genetic type although with a predominance of two phyla: the Firmicutes and Bacteroidetes for all ducks species. Different conditions encountered in the environment are likely to create an imbalance in the composition of the microbiota. One is a change in diet; therefore the second step was to see the impact of overfeeding on bacterial communities. Overfeeding causes many changes in the bacterial microbiota and increase two classes: Bacilli and Clostridia according to the genetic type. The effect of overfeeding has been shown principally on the ileal microbiota while genetics and overfeeding both affected weekly cecal microbiota. We then studied the impact of adding a probiotic strain (Lactobacillus sakei) on the microbiota of mule ducks during the overfeeding period. We could see here a significant effect of this addition only in the ileum with a sharp increase in lactobacilli. Finally, due to high levels of contamination found in the southwest of France and its toxic effects on metabolism shown in various studies, the last work was to see the effect of cadmium on the microbiota of Pekin and Muscovy ducks. We observed changes in the microbial community when adding cadmium and see the accumulation of it in the kidneys during overfeeding. Combined effects between cadmium and the feeding period as well as the genetic type were highlighted. Finally
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Effects of alcohol on the development of the cardiovascular system in Pekin Ducks (Anasplatyrhynchos): An assessment of current empirical findings and the development of aresearch protocol utilizing Pekin DucksMcKean, Josephine Kay 30 April 2021 (has links)
No description available.
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Victoria MS Thesis_final vers.pdfVictoria K Tetel (15354490) 27 April 2023 (has links)
<p> </p>
<p>Glucocorticoids (GC) play a critical role in regulating the physiological response to stress. Disruptions to baseline levels due to stress can have negative implications on a variety of factors including growth and development, physical body conditions, metabolism, immune functions, and expression of normal behaviors, although this list is not exhaustive. When birds are unable to adapt to the stressor and return to homeostasis, the energy expenditure associated with the failed attempt at coping can lead to significant declines in the overall health, welfare, production, and performance of the bird. This can go on to impact producers and consumers as well, indicating the extensive repercussions of stress. Recently, scientists have been investigating thorough and efficient methods of quantifying stress in birds, such as measuring heterophil-to-lymphocyte ratio (HLR) or detecting glucocorticoid levels through enzyme-linked immunoassays (ELISA). However, the precise mechanism behind HLR increase during stress is unknown and ELISAs may not provide accurate results depending on when the blood is being measured. </p>
<p><br></p>
<p>GC are differentially released and exert their effects in a manner that is dependent on sex, age, and time. However, before investigating this, it was critical to validate the GC kits to ensure that they were measuring cortisol and corticosterone separately along with zero cross reactions with other precursors. Chapter 2 had 4 experiments carried out. The objective of experiment 1 was to validate ELISAs to ensure that they were measuring the GC accurately and separately since both cortisol and corticosterone were being measured. To do this, duck serum was pooled and charcoal-stripped to remove the presence of steroids. 3 standard curves were run to confirm that there was no cross reactivity. The objective of experiment 2 was to further validate the ELISA kits with mass spectrometry by checking for both glucocorticoids in the pooled samples. Once the validation process was complete, experiment 3 was carried out to look at the effect of ACTH stimulation on GC release. 16-week-old drakes and hens were given either intramuscular (IM) injections of cosyntropin (0.06 mg/kg) or saline as control. The cosyntropin dose was chosen according to previous studies reporting relatively high physiological responses, therefore, we wanted to replicate this. N was 10/sex/treatment. Blood was then collected at 0, 1, and 2 hours after injections and serum was analyzed by ELISAs. Lastly for experiment 4, 14-week-old developer drakes and hens at Maple Leaf Farms were assessed for a transportation stress experiment. Blood from 10 ducks/sex/time/barn were collected at 24 hours before transport to the breeder barn, immediately after a 1-hour transport, 24 hours after, and 1 week after transport. The results from experiment 1 yielded that both cortisol and corticosterone can be measured without the presence of unwanted contaminants or other products. Experiment 2 identified the greater sensitivity of mass spectrometry when reading GC levels, although the differences were linear. Experiment 3 showed that serum corticosterone levels were significantly increased at 1 hour after ACTH injections in both drakes and hens, with levels continuing to increase for the drakes. Serum cortisol levels were significantly increased at 1 hour after ACTH injections in both sexes, however, the hens had greater levels compared to the drakes. Serum cortisol levels returned to levels similar to that of saline-injected ducks at the 2-hour mark. Lastly, the transportation stress portion showed that cortisol was released at about 1/3 of corticosterone levels in both sexes. Hens showed increased levels of serum corticosterone compared to drakes at all time points except for 1 week after transport, and also had significantly increased serum cortisol levels at all time points. In conclusion, the ELISA kits were verified for future use when measuring GC as well as mass spectrometry. GC were detected in the ACTH and transportation stress experiments with hens displaying a greater sensitivity to GC release due to increased circulating levels compared to drakes. Although it was nonsignificant, there was a trend for GC to increase in response to transport. </p>
<p><br></p>
<p>There are sex differences in GC release and HLR for Pekin ducks and various challenges from the studies support this. With hens showing increased sensitivity to stress and drakes with more transient and gradual levels, we have consistently seen that both GC have differential roles in the stress response and not only is it critical to study both hormones, the timing of when measurements are taken are important as well to get a clear understanding of when the stress response is initiated. </p>
<p><br></p>
<p>Chapter 3 went further to understand the response of GC and HLR. The objective was to investigate the release of cortisol and corticosterone in response to an ACTH dose response challenge. In Chapter 2, only one dose of cosyntropin was used and sample collection times only went to 2 hours after injections. In this study, 2 additional doses and an extra hour of sample collection were added to obtain more information. Pekin ducks were either given IM cosyntropin injections or saline for control, with an N of 10/sex/treatment. There were 3 treatment doses: High (0.06 mg/kg), medium (0.03 mg/kg), and low (0.015 mg/kg). All injections were given promptly at 0730 hours. Blood was collected at 0, 1, 2 and 3 hours after injections from the tibia veins to obtain serum for ELISAs. Blood smears were done to analyze HLR and sent to an independent lab to obtain values. The results indicated that both GC had significant sex x dose x time interactions. The low dose injection had no effect on corticosterone in hens with a slight increase for drakes at the first hour. The high dose for hens led to a spike in corticosterone levels at the first hour with a gradual decrease, and drakes had an increase that lasted for 2 hours until they returned to baseline at the last hour. The high dose in drakes stimulated cortisol release during the first 2 hours after injection with a similar effect in hens. However, hens had elevated levels compared to drakes. Finally, there was no dose response effect for HLR, although interestingly, the low dose injection elevated HLR even though there was no effect in GC. There were sex differences in the HLR response where the drakes given the high dose had levels that plateaued by the third hour, while the hens still had elevated levels. In conclusion, the ACTH dose-response test identified that ACTH has a dose-dependent effect in both GC and sex differences in their release. HLR also showed sex differences that did not depend on the dose given.</p>
<p><br></p>
<p>Chapter 4 observed acute exposure of GC in ducks. Pekin ducks were assigned 10/sex/treatment to receive either IM control, cortisol, or corticosterone injections. In addition, a low-dose cortisol treatment was given to represent the endogenous levels of cortisol compared to corticosterone. The control injections contained safflower oil, which was chosen as vehicle due to the low levels of genistein present. This is important as genistein is a plant estrogen and this could interact with the GC and alter the results. Blood was collected at 0, 1, 2, and 3 hours after injections for serum analysis with ELISAs, and blood smears were collected for complete blood count (CBC) differentials. Significant sex x treatment x time interactions were notable in both GC. Hens had significant increases at the first hour after injections in all treatments compared to controls, and drakes had increases at 2 hours after injections in all treatments except the low-dose cortisol. </p>
<p><br></p>
<p>After observing the effect of acute stress in ducks, the next step was to investigate the effects of chronic stress in chapter 5. Adult breeder Pekin ducks were randomly distributed into 3 groups: corticosterone, cortisol, or control treatments. The GC were in crystalline steroid form distributed through 2 capsules that were subcutaneously implanted on the backs of the neck. The ducks in the control group were given empty capsules. Blood smears, blood draws for serum, egg collection, body weights, and organ samples were collected over a period of 2 weeks. For the results, the corticosterone implants elevated corticosterone levels in both sexes. Interestingly, cortisol levels were elevated in both GC treatments in both sexes. Cortisol elevated HLR in drakes 1 day after implants with no effect from corticosterone. Hens had elevated HLR from both GC at all timepoints throughout the experiment. There were no significant differences in morphometrics in either sex. Corticosterone was not present in eggs, but cortisol was elevated in the albumen on day 7 and 14 of the experiment. Overall, there were sex differences in HLR where hens had greater levels in both GC treatments.</p>
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POTENTIAL EFFECTS OF PARENTAL HEAT STRESS EXPOSURE ON HYPOTHALAMIC-PITUITARY-ADRENAL AXIS SENSITIVITY THROUGH EPIGENETIC PROCESSES.Esther Mary Oluwagbenga (15354481) 29 April 2023 (has links)
<p> </p>
<p>Heat stress affects breeder ducks raised in North America and other parts of the world, but the effects of such stress on the progenies is not known. Therefore, the objectives of this study were to investigate: 1) The objectives of this thesis were to first investigate the effect of heat stress or exposure to exogenous glucocorticoid (GC) on fertility, production performance, egg biochemistry, egg quality, and welfare of breeder Pekin ducks. 2) the effects of maternal GC on phenotypic plasticity and behavior of the F1 generation. Three studies were carried out to investigate these objectives.</p>
<p>The first experiment was conducted to test the hypothesis that chronic treatment with low levels of either corticosterone or cortisol would alter heterophil to lymphocyte ratio (HLR) and immune organ morphometrics. Further, we wanted to determine if chronic treatment with either GC would elicit an increase in cortisol levels in egg albumen. To test our hypotheses, we implanted silastic capsules subcutaneously under the skin of the neck of adult ducks (n = 5/sex/dose) using propofol anesthesia. Capsules contained corticosterone, cortisol, or empty capsules as controls. Over the course of 2 weeks, blood serum, blood smears, body weights, and egg quality data were collected. After 2 weeks, ducks were euthanized using pentobarbital (FatalPlus, 396 mg/ml/kg) and body weight, weights of spleens, livers, and the number of active follicles were recorded. Blood smears were analyzed for HLR by a lab unaware of the treatment groups. Albumen GC levels were assessed using mass spectrometry. Data were analyzed using a 2- or 3-way ANOVA as appropriate and <em>post hoc </em>with Fishers protected least squares difference (PLSD). There were no treatment effects on egg quality measures or body weight. Corticosterone treatment did elicit an increase in serum corticosterone (p < 0.05), but not cortisol levels, compared to controls in both sexes. Both cortisol and corticosterone treatments increased (p < 0.05) serum levels of cortisol compared to controls. Relative spleen weights were higher (p < 0.05) in hens following corticosterone but not cortisol treatment. No other organs showed any differences among the treatment groups. Both GCs elicited an increase (p < 0.001) in HLR in hens at all time-points over the 2-week treatment period compared to controls. Cortisol, not corticosterone, elicited an increase in HLR for drakes (p < 0.05) compared to controls at day 1 after implants. Chronic treatment with cortisol, but not corticosterone, elicited an increase (p < 0.01) in egg albumen cortisol levels compared to other groups. Corticosterone was not detected in any albumen samples.</p>
<p>The goal of our second experiment was to test the hypothesis that heat stress (HS) would alter welfare, egg quality, and morphometrics of breeder ducks. Furthermore, we wanted to test if HS would increase cortisol levels in egg albumen due to recent exciting findings that cortisol, not corticosterone, is isolated in egg albumen. To test our hypothesis, adult Pekin ducks were randomly assigned to two different rooms at 85% lay with 60 hens and 20 drakes per room. Baseline data including body weight, body condition scores (BCS) (such as footpad quality, eyes, nostrils, feather cleanliness, and feather quality scores), and egg production/quality were collected the week preceding heat treatment. Ducks were subjected to cyclic HS of 350C for 10h/day and to 29.50C for the remaining 14h/day for 3 weeks while the control room was maintained at 220C. Eggs were collected daily, and body weights were taken on days 0 and 21 relative to the onset of heat treatment. BCS were collected weekly. Eggs were collected weekly for quality assessment and albumen glucocorticoid (GCs) levels assessment using mass spectrometry. One week before the exposure to HS, 10 hens and 5 drakes were euthanized and the same number again after 3 weeks of HS or control exposures using pentobarbital and birds necropsied. Body weight, weights of the liver, spleen, and the number of maturing follicles were recorded. Data analyses were done by 2- or 3-way ANOVA as appropriate with a Tukey-Kramer post hoc test. BCS were analyzed using a chi-squared test. A p value ≤ 0.05 was considered significant. Circulating levels of corticosterone were significantly (p < 0.01) elevated at week 1 only in the HS hens while there was no significant difference in the circulating levels of corticosterone in drakes compared to the controls. The circulating levels of cortisol increased significantly at week 1 (p < 0.05), week 2 (p < 0.05), and week 3 (p < 0.01) in the hens and at week 2 and 3 only (p < 0.05) in the drakes compared to the controls. Feather quality scores (p < 0.01), feather cleanliness scores (p < 0.001) and footpad quality scores (p < 0.05) increased significantly in the HS group compared to controls, higher BCS indicate a decline in welfare. HS elicited a significant (p < 0.001) decrease in egg production at weeks 1 and 3 and a descriptive decrease in the number of fertile eggs upon candling at 10 days of incubation, numeric decrease hatchability and increase in the number of dead embryos in the HS group after the incubation period. Hens in the HS group showed a significantly decreased BW (p < 0.001), and number of ovarian follicles (p < 0.05) compared to controls. Shell weight decreased significantly at week 1 (p < 0.05) compared to controls. Yolk weight decreased significantly at week 3 (p < 0.01) compared to controls. HS elicited a significant increase in albumen cortisol levels at week 1 (p < 0.05) and week 3 (p < 0.05).</p>
<p>The third experiment was conducted to determine if parental exposure to heat stress would impair performance, hypothalamic pituitary adrenal (HPA) axis response, welfare, or behavior of their offspring. To achieve these goals, we treated adult drakes and hens at peak lay to heat stress or control temperature for 3 weeks and incubated eggs collected from the last 3 days of the experiment. A total of 76 ducklings were placed into pens from each parental treatment group: control (CON-F1) and heat stress (HS-F1) and raised as grow-out ducks. Weekly data for body weights, body condition scores (BCS), and novel object test (NOT) were collected weekly. At 3 weeks of age, ducks (n = 6 per treatment group) were subjected to adrenocorticotropic hormone (ACTH) (ACTH/cosyntropin, 0.0625 mg/kg) challenge or vehicle as control. Blood samples were collected from the metatarsal vein into serum-separator tubes at 0, 1, 2, 3, and 4 hours relative to treatment for the determination of serum glucocorticoids. Blood smears were also produced from these same samples to determine heterophil to lymphocyte ratios (HLR). All injected birds were euthanized with pentobarbital on the second day relative to ACTH administration, spleen and bursa were removed and weighed immediately. Duck level analyses were completed using 1-, or 2 -way ANOVA as appropriate. BCS were analyzed using a chi-squared test. We observed that HS-F1 had a lower hatch weight (p < 0.05) compared to CON-F1. However, growth rates during the 5-week grow-out period were not significantly different between the two flocks. NOT (N = 4) analyses showed that the HS-F1 had a greater fear response (P< 0.001) compared to CON-F1. Similarly, an ACTH stimulation test showed that the HS-F1 ducks had significantly heightened corticosterone and HLR responses compared to CON-F1 ducks (p < 0.05). The HS-F1 showed altered baseline and ACTH-stimulated levels of cortisol compared to controls.</p>
<p>In conclusion, GC elicit differential effects and although corticosterone has been stated to be the predominant GC in avian species, cortisol may provide critical information to further understand and improve welfare. HS decreased performance, fertility, and productivity of breeder ducks. In addition, HS and exogenous GC elicited a selective deposition of cortisol, not corticosterone, in the egg albumen. The maternal cortisol deposited in eggs alter the hypothalamic-pituitary adrenal (HPA) axis and behavioral responses of the F1 generation. This suggests that maternal hormones can alter the phenotypic plasticity of the offspring and can be used to produce offspring that have better adaptation to the rising temperatures as a result of climate change. Finally, the measure of cortisol in egg albumen can be used as a non-invasive marker of stress.</p>
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Mail Order Music: the Hinners Organ Company in the Dakotas, 1879-1936Alcorn-Oppedahl, Allison A. (Allison Ann) 08 1900 (has links)
Founded in 1879 by John L. Hinners, the Hinners Organ Company developed a number of stock models of small mechanical-action instruments that were advertised throughout the Midwest. Operating without outside salesmen, the company was one of the first to conduct all of its affairs by mail, including the financial arrangements, selection of the basic design, and custom alterations where required. Buyers first met a company representative when he arrived by train to set up the crated instrument that had been shipped ahead of him. Tracker organs with hand-operated bellows were easily repaired by local craftsmen, and were suited to an area that, for the most part, lacked electricity. In all, the company constructed nearly three thousand pipe organs during its sixty years of operation. Rapid decline of the firm began in the decade prior to 1936 during which the company sold fewer than one hundred instruments, and closed in that year when John's son Arthur found himself without sufficient financial resources to weather the lengthy depression. The studies of the original-condition Hinners organs in the Dakotas include extensive photographs and measurements, and provide an excellent cross section of the smaller instruments produced by the company. They are loud, excellently crafted, functionally attractive, tonally typical of the early twentieth-century American Romantic organ, and utilize designs and materials typical of this era. Only recently has it been acknowledged that these Hinners organs represent a "meat and potatoes" class of instrument, as it were, an honest meal without the pretense of delicate appetizers, vintage wine, and gourmet dessert. In this way the company offered churches a serviceable and respectable musical alternative to grandeur, and was able to fulfill the needs and meet the budget of a small congregation without the expense of a custom instrument.
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