<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>

The aim of this work was to investigate the effects of feather availability and imprinting to loose feathers in the litter on the incidence of feather pecking behaviour (FP), condition of the integument and fear reactions in two genotypes of laying hens. Hens that were deprived from loose feathers in the litter (feathers were collected 4 times/week) exhibited a significantly less rate of feather pecking, less number of severe FP and showed a better feather score in the laying period compared to the control groups (no feather treatment) in both Lohmann Tradition (LT) & Lohmann Silver (LS) genotypes. Addition of brown feathers to the floor in LT hens (feathers were added once/week) was associated with a reduction in feather pecking rate, the severe form of this behaviour and improved plumage and skin conditions. Contrary, the addition of white feathers to the floor in LS was associated with the highest rate of feather pecking, the highest severe form of this behaviour as well as the worst feather and skin conditions in the laying period compared to other groups of the same genotype. The LT birds in all feather treatments had a better feather cover than the LS birds. Hens that were imprinted to loose feathers in the litter in the rearing period exhibited a higher rate of FP, higher number of severe FP and showed the worst feather and skin conditions when feathers were collected from the floor during the laying period. Also, these hens reacted more fearful during the tonic immobility test. It is concluded that loose feathers may play a role in the development of feather pecking behaviour in laying hens. Large differences between genotypes were found in respect to the availability of loose feathers, feather pecking and plumage and integument condition. Imprinting of chicks to loose feathers from the floor may affect the incidence of feather pecking later on. Ziel dieser Arbeit war es, die Einflüsse des Federangebotes und der Prägung auf lose Federn in der Einstreu auf die Häufigkeit des Auftretens von Federpicken (FP), den Zustand des Integuments und die Furchtreaktionen an zwei Legehennengenotypen zu untersuchen. Hühnern beider untersuchter Genotypen (Lohmann Tradition (LT) und Lohmann Silber (LS)), denen die losen Federn 4 mal/ Woche aus der Einstreu abgesammelt wurden, zeigten eine geringere Federpickrate, eine geringere Anzahl der schweren Form des FP und eine bessere Gefiederbeschaffenheit in der Legeperiode verglichen mit der Kontrollgruppe (keine Federbehandlung). Das Hinzufügen brauner Federn zur Einstreu bewirkte bei LT Hennen eine Reduktion der FP-Rate, der schweren Form des Federpickens und verbesserte die Gefieder- und Hautbeschaffenheit. Dagegen führte das Hinzufügen weißer Federn in die Einstreu während der Legeperiode bei LS Hennen zur höchsten Federpickrate und Anzahl der schweren Form des Federpickens sowie zur schlechtesten Gefieder- und Hautbeschaffenheit im Vergleich zu anderen Gruppen des gleichen Genotyps. Hühner der LT Linie wiesen in allen Federbehandlungen eine bessere Befiederung als die LS Hühner auf. Hennen, die während der Aufzuchtsperiode auf lose Federn in der Einstreu geprägt wurden, zeigten nach Absammeln der Federn während der Legeperiode eine erhöhte FP-Rate mit einer erhöhten Anzahl der schweren Form des FP und die schlechteste Gefieder- und Hautbeschaffenheit. Außerdem reagierten diese Hühner ängstlicher während des Tests auf tonische Immobilität. Es kann geschlussfolgert werden, dass lose Federn in der Einstreu eine Rolle bei der Entwicklung des Federpickverhaltens von Legehennen spielen und dass Federpicken als Futtersuchverhalten interpretiert werden kann. Grosse Unterschiede zwischen den Genotypen bestanden hinsichtlich der Verfügbarkeit von losen Federn in der Einstreu, des Federpickens sowie der Gefieder- und Integumentbeschaffenheit. Eine Prägung der Junghennen auf lose Federn in der Einstreu könnte das Auftreten von Federpicken zu einem späteren Zeitpunkt beeinflussen.

A series of trials were conducted to determine the effect of feeding barley silage to laying hens and broiler breeder pullets on performance, stress and behaviour. In the first study, two trials were conducted each with 20 hens and 2 roosters (n=176) randomly assigned to one of 8 community cages. The birds in 4 cages were provided with a nutritionally balanced soy/wheatbased laying hen diet ad libitum, whereas the birds in another 4 cages were given free access to barley silage in addition to the regular laying hen diet. In both trials, the control birds consumed more feed (P < 0.05) than the birds given barley silage. Birds fed barley silage had significantly decreased (P < 0.05) aggressive and feather pecking behaviours as well as time spent in their nest boxes at different ages. Time spent drinking, resting, preening and eating a large particle calcium source was similar between the two treatments. No treatment effects (P > 0.05) were found in regards to egg quality, egg production and bird weights at various ages; however yolk colour was darker by silage treatment in each trial. At the end of each trial, the feather score was improved in silage-fed birds compared to the control birds. It was concluded that feeding barley silage as a supplement to laying hens can improve their welfare without negatively affecting the egg production and egg quality. <p>A second study was conducted to determine the effect of feeding barley silage on body weight, stereotypic behaviour, stress and fear on broiler breeder pullets during the brooding and rearing periods. The 3 week old broiler breeder pullets (n=180) were randomly allocated into 12 straw litter floor pens having 15 birds per pen. The birds in 6 pens were provided with a nutritionally balanced corn/oat-soybean/canola meal-based broiler breeder diet at recommended restricted levels, whereas the birds in another 6 pens were given free access to barley silage in addition to a regular broiler breeder diet. Total DM intake was significantly higher (P < 0.05) for silage-fed birds compared to their control counterparts without affecting mean body weights. Dietary treatment had no significant effect on bird behaviour with the exception of object pecking behaviour which was reduced with silage feeding. Aggressive and gentle feather pecking behaviour was consistently numerically higher in the control birds than the silage-fed birds, although not significantly. Age affected many of the behaviours recorded in this study. Silage feeding had no significant effect on heterophil to lymphocyte ratios and tonic immobility values indicating that birds in both treatments were not very stressed or fearful. It was concluded that feeding barley silage to broiler breeder pullets has potential to aid in improving their welfare.

A series of trials were conducted to determine the effect of feeding barley silage to laying hens and broiler breeder pullets on performance, stress and behaviour. In the first study, two trials were conducted each with 20 hens and 2 roosters (n=176) randomly assigned to one of 8 community cages. The birds in 4 cages were provided with a nutritionally balanced soy/wheatbased laying hen diet ad libitum, whereas the birds in another 4 cages were given free access to barley silage in addition to the regular laying hen diet. In both trials, the control birds consumed more feed (P < 0.05) than the birds given barley silage. Birds fed barley silage had significantly decreased (P < 0.05) aggressive and feather pecking behaviours as well as time spent in their nest boxes at different ages. Time spent drinking, resting, preening and eating a large particle calcium source was similar between the two treatments. No treatment effects (P > 0.05) were found in regards to egg quality, egg production and bird weights at various ages; however yolk colour was darker by silage treatment in each trial. At the end of each trial, the feather score was improved in silage-fed birds compared to the control birds. It was concluded that feeding barley silage as a supplement to laying hens can improve their welfare without negatively affecting the egg production and egg quality. <p>A second study was conducted to determine the effect of feeding barley silage on body weight, stereotypic behaviour, stress and fear on broiler breeder pullets during the brooding and rearing periods. The 3 week old broiler breeder pullets (n=180) were randomly allocated into 12 straw litter floor pens having 15 birds per pen. The birds in 6 pens were provided with a nutritionally balanced corn/oat-soybean/canola meal-based broiler breeder diet at recommended restricted levels, whereas the birds in another 6 pens were given free access to barley silage in addition to a regular broiler breeder diet. Total DM intake was significantly higher (P < 0.05) for silage-fed birds compared to their control counterparts without affecting mean body weights. Dietary treatment had no significant effect on bird behaviour with the exception of object pecking behaviour which was reduced with silage feeding. Aggressive and gentle feather pecking behaviour was consistently numerically higher in the control birds than the silage-fed birds, although not significantly. Age affected many of the behaviours recorded in this study. Silage feeding had no significant effect on heterophil to lymphocyte ratios and tonic immobility values indicating that birds in both treatments were not very stressed or fearful. It was concluded that feeding barley silage to broiler breeder pullets has potential to aid in improving their welfare.

This thesis investigates the use of an enzyme immunoassay to measure keratin glucocorticoid concentrations in mammalian hair, bird feathers and reptilian shed skins. Keratin glucocorticoid concentrations were compared to fecal glucocorticoid concentrations produced during the period of keratin growth in the African Elephant (Loxodonta africana), the Western Lowland Gorilla (Gorilla gorilla gorilla), the Sumatran Orangutan (Pongo abelii), the Domestic Chicken (Gallus gallus domesticus), the Eastern Loggerhead Shrike (Lanius ludovicianus migrans), the African House Snake (Lamprophis fuliginosus) and the Eastern Massasauga Rattlesnake (Sistrurus catenatus catenatus). Complete biochemical validation was performed for the feather and shed skin corticosterone and fecal corticosterone enzyme immunoassays in the Domestic Chicken and the African House Snake. Biological validation was performed in the Domestic Chicken. Biological and physiological validation were attempted in the African House Snake. African Elephant, Western Lowland Gorilla and Sumatran Orangutan hair cortisol concentrations ranged from 2.10 - 312.70 ng/g. African Elephant hair corticosterone concentrations ranged from 2.68 - 20.70 ng/g. Domestic Chicken and Eastern Loggerhead Shrike feather corticosterone concentrations ranged from 1.31 - 8.09 pg/mm and from 1.09 - 6.59 pg/mm, respectively. African House Snake and Massasauga Rattlesnake shed skin corticosterone concentrations ranged from 4.42 - 124.35 ng/g and 3.82 - 22.85 ng/g, respectively. In the majority of cases, a statistically significant association was not found between summary statistical measures of fecal and keratin glucocorticoid concentrations. A statistically significant positive association was detected between hair cortisol and the coefficient of variation of fecal corticosterone in the African Elephants. A statistically significant negative association was detected between feather corticosterone and the 75th percentile and coefficient of variation of fecal corticosterone in the Eastern Loggerhead Shrikes. A statistically significant positive association was also detected between shed skin corticosterone and the mean fecal corticosterone from 3 weeks before to 1 week after the previous ecdysis in the African House Snake. Feather corticosterone concentrations were significantly higher in feathers from Domestic Chickens that were socially housed with roosters than in feathers from chickens housed individually in laying cages. A statistically significant difference was not detected between the shed skin corticosterone concentrations of the minimally handled control and the weekly handled experimental African House Snakes. Adrenocorticotropic hormone stimulation did not result in the physiological validation anticipated for shed skin corticosterone concentrations in the African House Snake. / Toronto Zoological Foundation and Ontario Ministry of Agriculture, Food and Rural Affairs

Thesis (Ph. D. )--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 120-131). Also available on the World Wide Web.

Polychaetes are among the most abundant and diverse groups in the benthic environment; however, the diversity of marine polychaetes remains underexplored. On coral reef ecosystems, scientists predict 80-90% of species are still undescribed due to low sampling efforts in certain regions and the understudied nature of smaller invertebrates, such as polychaetes. Sabellidae, a prominent family of polychaetes, are known for their widespread distribution and are recognized as an ornamental worm due to their feather-like appendages. Here, we detail the diversity of Sabellidae around the understudied Arabian Peninsula. The Arabian Peninsula is surrounded by diverse marine ecosystems (e.g., coral reefs, seagrass beds) occurring in extreme environmental conditions (e.g., higher seawater temperature and strong seasonal variation). Our samples included 178 sabellids from the Saudi Arabian Red Sea, the Arabian Sea, and the Arabian Gulf. Collected from February 2019 to February 2020, these sabellids were sampled from hard and soft substrate on coral reefs and their associated habitats. We used two molecular markers, the cytochrome c oxidase subunit I (COI) and 16S ribosomal DNA alongside an array of morphological analyses, including widely used characters, meristic counts, and morphometric measurements, to identify seven morphotypes. Environmental and biological information was also recorded to understand more about the ecology of these relatively understudied polychaetes. Our combined morphological and genetic analyses acknowledge the presence of six species from the genera Sabellastarte, Bispira, Branchiomma, and Acromegalomma. Our study identified the existence of potential undescribed species in the region and proposed expanded geographic ranges for three accepted species, Sabellastarte sanctijosephi, Branchiomma luctuosum, and Acromegalomma nechamae. The present work increases the current knowledge about the overall systematics of marine polychaetes in the Arabian Peninsula and ultimately contributes to the reassessment of the family’s biogeography.

No description available.

No description available.

Chickens exhibit considerable variation in morphological traits, with some populations having undergone intensive selection for uniqueness and uniformity. These populations are a source of experimental material to study the genetics of morphological traits. An important first step in such studies is to map the genes and the causal mutations that influence these traits. This research focused on gene mapping of 12 morphological traits including 4 intra-feather color patterns (Pattern, Columbian, Melanotic, and mottling), 2 inter-feather color patterns (Blue and chocolate), 2 forms of feathered-legs, polydactyly, dark brown eggshell color, vulture hock, and creeper. Ten backcross and/or F2 populations were designed to produce 1,880 individuals. An additional 339 DNA samples from other populations were included. The procedures for gene mapping were: 1. Pooling of DNA samples of backcross or F2 individuals based on their shared phenotypes, followed by microarray assays for genotyping, a cost-effective initial screen for the candidate genomic regions, 2. Linkage mapping to narrow the range of candidate genes, 3. Sequencing to identify the candidate mutations, 4. Diagnostic tests to confirm the association between the candidate mutation and the phenotype. Of the 12 traits studied, 3 (mottling, Blue, and chocolate) made progress into step 4. Complexities due to genomic context, modifiers, and environmental factors precluded step 4 for the first form of the feathered-leg gene, step 3 for the mapping of Melanotic, and earlier stages for the mapping of Pattern, Columbian, dark brown egg, vulture hock, and the second form of feathered-leg. These findings provide insights of the complexity of how background genome can influence the phenotypic expression of single genes (gene genetic background interactions) and an understanding of cellular and molecular mechanisms involved in morphogenesis. / Ph. D. / Chickens, one of the major protein sources in diets for humans, have a long cultural, sport and religious history since their initial domestication during the neolithic period. Darwin wrote of the importance of variation, which today we see for example in size of body, length of shank, number of toes, distribution of feathers, comb types, and plumage color patterns resulting in a plethora of breeds of chickens that differ in appearance. Some of these traits are "simply" inherited, which in the molecular era facilitates the study of relationships between DNA sequences and phenotypes. This dissertation focuses on identification of differences in DNA sequences among chickens responsible for these "simply" inherited phenotypes. The 12 phenotypes that were studied included 6 plumage color patterns (Pattern, Columbian, Melanotic, mottling, Blue, and chocolate), 2 forms of feathered-legs, polydactyly, dark brown eggshell color, vulture hock, and creeper. Designed were ten 3-generation populations to produce 1,880 chickens. An additional 339 DNA samples from other populations were included. Of the 12 phenotypes, 8 involved genotyping of pooled DNA samples, a cost-effective initial screen to target DNA sequences. This was followed by genotyping individual samples in 5 of the more promising studies. Candidate genes identified as associated with these 5 phenotypes underwent further studies which identified differences in DNA sequences associated with 4 of them (mottling, feathered-leg, Blue, and chocolate). These findings provide insights of how DNA sequences contribute to the phenotypic appearance of animals.