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1.
Environ Monit Assess ; 194(1): 26, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34907468

RESUMO

The amounts of certain heavy metals in waterfowl fluctuate depending on a number of factors. The use of feathers in heavy metal contamination studies is gaining popularity for several reasons, including the lack of need for deep freezing for sample preservation, the fact that it is a non-destructive, non-invasive method that does not require killing an individual, and the ability to predict lead and cadmium concentrations in internal tissues. A total of 22 publications from eight Asian countries including Pakistan, China, Hong Kong, India, Iran, South Korea, Indonesia, and Japan were identified and analysed in this study. The highest number of study sites were found from Pakistan (n = 12), followed by China (n = 9), Hong Kong, South Korea, and India (n = 7) each. A total of 10 heavy metals, viz cadmium, chromium, lead, copper, nickel, zinc, iron, mercury, selenium, and arsenic, have been identified for the review. Mercury (0.17-79.66 ppm) has been studied in all 44 species, whereas selenium (0.98-4.88 ppm) has only been studied in five species. Mercury (8.6 ppm) contamination is highest in Painted Stork from India. Cadmium, lead, copper, and arsenic contamination was detected in the highest concentrations in Cattle Egret and Indian Pond Heron. The highest contamination of cadmium (41.1 ppm), lead (296 ppm), and arsenic (20 ppm) were found in Cattle Egret from Pakistan. Chromium, nickel, and zinc contamination was highest in waders such as Marsh Sandpiper (114.7 ppm), Little Ringed Plover (114.8 ppm), and Little Stint (328.4 ppm), respectively from India. Black-tailed Gull from South Korea had the highest contamination of Iron (4055.55 ppm) and selenium (7.55 ppm). Feather analysis is not an alternative of internal tissue analysis. It should be considered as an initial warning of the hazardous effects of the heavy metals in the waterbirds.


Assuntos
Mercúrio , Metais Pesados , Animais , Bovinos , Monitoramento Ambiental , Plumas/química , Hong Kong , Mercúrio/análise , Metais Pesados/análise
2.
Poult Sci ; 100(12): 101494, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34695634

RESUMO

The feather corticosterone concentration (fCORT) is increasingly used to assess long-term stress in birds as this indicator provides the potential to retrospectively evaluate the adrenocortical activity of a bird during the growth period of a feather over several weeks in one sample. However, there is still a lack of knowledge concerning external factors which can potentially influence fCORT in birds. The aim of the present study was to determine whether fCORT in laying hens is affected by previous fecal contamination of the plumage. Fully grown primaries 5 (P5s) of laying hens (n = 40) were used for the study. To test the effects of fecal contamination on fCORT, freshly defecated droppings from laying hens were collected and mixed manually. In order to simulate practical and at the same time standardized contamination, the upper surface of the previously determined middle third of the right P5 of each hen then was evenly coated with the paste prepared from fresh feces. The treated feathers were stored for 24 h protected from light at room temperature under a film cover to prevent evaporation. Thereafter, the applied layer of excreta was removed manually. Contralateral P5s of the same individuals were stored under identical conditions and served as controls. Both treatment and control feathers were washed in an aqueous soap solution, rinsed several times in pure water and air-dried subsequently. After pulverization and methanolic extraction, fCORT was analyzed by ELISA. The mean fCORT of treatment P5s (reference 'feather length': 12.88 ± 3.16 pg/mm; reference 'feather weight': 7.81 pg/mg ± 1.86 pg/mg) were significantly higher (P < 0.001) than those of control P5s (reference 'feather length': 9.76 ± 2.42 pg/mm; reference 'feather weight': 5.93 ± 1.44 pg/mg). Our results show that previous contamination with excreta can increase fCORT, which was detectable even after a washing procedure prior to analysis. In conclusion, fecal contamination of feathers is a significant influencing factor that has to be considered when applying fCORT measurements.


Assuntos
Corticosterona , Plumas , Animais , Galinhas , Fezes , Feminino , Estudos Retrospectivos
3.
Poult Sci ; 100(12): 101500, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34700097

RESUMO

Beak treatment is an effective method of reducing the damage inflicted by severe feather pecking (SFP) but there is significant pressure to eliminate these treatments and rely solely on alternative strategies. Substantial variation in beak shape exists within non-beak treated layer flocks and beak shape appears to be heritable. There is the potential to use this pre-existing variation and genetically select for hens whose beak shapes are less apt to cause damage during SFP. To do this, we must first understand the range of phenotypes that exist for both the external beak shape and the bones that provide its structure. The objective of this study was to determine the variation in premaxillary (within the top beak) and dentary (within the bottom beak) bone morphology that exists in 2 non-beak treated pure White Leghorn layer lines using geometric morphometrics to analyze radiographs. Lateral head radiographs were taken of 825 hens and the premaxillary and dentary bones were landmarked. Landmark coordinates were standardized by Procrustes superimposition and the covariation was analyzed by principal components analysis and multivariate regression using Geomorph (an R package). Three principal components (PCs) explained 85% of total premaxillary bone shape variation and showed that the shape ranged from long and narrow with pointed bone tips to short and wide with more curved tips. Two PCs explained 81% of total dentary bone shape variation. PC1 described the dentary bone length and width and PC2 explained the angle between the bone tip and its articular process. For both bones, shape was significantly associated with bone size and differed significantly between the two lines. Bone size accounted for 42% of the total shape variation for both bones. Together, the results showed a range of phenotypic variation in premaxillary and dentary bone shape, which in turn may influence beak shape. These bone phenotypes will guide further quantitative genetic and behavioral analyses that will help identify which beaks shapes cause the least damage when birds engage in SFP.


Assuntos
Bico , Galinhas , Animais , Galinhas/genética , Plumas , Feminino
4.
Braz J Biol ; 83: e252059, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34669810

RESUMO

The present study describes the haematological profile, feeding preference, and comparison of morphometric characters of blue rock pigeon (Columba livia) breeding pairs. For this purpose, 25 pairs (25 samples per sex) were sampled through Mist nets from district Okara and Bahawalnagar, Punjab, Pakistan. Birds were then anaesthetized with a combination of ketamine HCL (10 mg/kg) and diazepam (0.2 mg/kg) and subjected to morphometric measurements. 5µL blood also was taken from the jugular vein of each anaesthetized bird for haematological analysis. Few pairs were also dissected to remove gastrointestinal tracts (GITs) for food preferences. Results revealed that there are no significant differences in the haematological parameters and feeding preference of breeding pairs of Columba livia. The gut analysis further revealed, the major portion of gut contents consisted of pea and corn in most of the pairs. Regarding the mensural measurements, significant differences were recorded in the body weight, length of the longest primary feather, and chest circumference, whereas the rest of the studied parameters remain nonsignificant between sexes. So, it is concluded that apart from 3 morphometric parameters (body weight, length of longest primary feather and chest circumference), both sexes are alike in term of morphometry, haematology and food preference.


Assuntos
Columbidae , Preferências Alimentares , Animais , Plumas , Paquistão , Melhoramento Vegetal
5.
Int J Mol Sci ; 22(17)2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34502506

RESUMO

Poultry feathers are among the most abundant and polluting keratin-rich waste biomasses. In this work, we developed a one-pot microwave-assisted process for eco-friendly keratin extraction from poultry feathers followed by a direct electrospinning (ES) of the raw extract, without further purification, to obtain keratin-based bioplastics. This microwave-assisted keratin extraction (MAE) was conducted in acetic acid 70% v/v. The effects of extraction time, solvent/feathers ratio, and heating mode (MAE vs. conventional heating) on the extraction yield were investigated. The highest keratin yield (26 ± 1% w/w with respect to initial feathers) was obtained after 5 h of MAE. Waste-derived keratin were blended with gelatin to fabricate keratin-based biodegradable and biocompatible bioplastics via ES, using 3-(Glycidyloxypropyl)trimethoxysilane (GPTMS) as a cross-linking agent. A full characterization of their thermal, mechanical, and barrier properties was performed by differential scanning calorimetry, thermogravimetric analysis, uniaxial tensile tests, and water permeability measurements. Their morphology and protein structure were investigated using scanning electron microscopy and attenuated total reflection-infrared spectroscopy. All these characterizations highlighted that the properties of the keratin-based bioplastics can be modulated by changing keratin and GPTMS concentrations. These bioplastics could be applied in areas such as bio-packaging and filtration/purification membranes.


Assuntos
Plumas/química , Queratinas/química , Queratinas/isolamento & purificação , Ácido Acético/química , Animais , Varredura Diferencial de Calorimetria/métodos , Microscopia Eletrônica de Varredura/métodos , Micro-Ondas , Solventes , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
6.
Artigo em Inglês | MEDLINE | ID: mdl-34574839

RESUMO

Polar regions, symbols of wilderness, have been identified as potential sinks of mercury coming from natural and anthropogenic sources at lower latitudes. Changes in ice coverage currently occurring in some areas such as the Antarctic Peninsula could enhance these phenomena and their impacts on local biota. As long-lived species at the top of food chains, seabirds are particularly sensitive to this highly toxic metal with the capacity to be biomagnified. Specifically, their feathers can be useful for Hg monitoring since they mainly accumulate its most toxic and persistent form, methyl-Hg. To that end, feathers of gentoo (Pygoscelis papua), chinstrap (P. antarcticus), and Adélie penguins (P. adeliae) (n = 108) were collected by passive sampling in seven different locations throughout the Antarctic Peninsula area and analyzed by ICP-MS after microwave-digestion. More than 93% of the samples showed detectable Hg levels (range: 6.3-12,529.8 ng g-1 dry weight), and the highest ones were found in the feathers of chinstrap penguins from King George Island. Hg bioconcentration and biomagnification seem to be occurring in the Antarctic food web, giving rise to high but non-toxic Hg levels in penguins, similar to those previously found in Arctic seabirds.


Assuntos
Mercúrio , Spheniscidae , Animais , Regiões Antárticas , Plumas/química , Cadeia Alimentar , Mercúrio/análise
7.
Poult Sci ; 100(11): 101417, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34530230

RESUMO

This study was conducted to investigate the effect of stocking density on growth performance, feather quality, serum hormone, and intestinal development of geese from 1 to 14 d of age. A total of 450 one-day-old geese were randomly allotted to 45 battery cage (0.65 m × 0.62 m) pens according to 5 stocking densities (15, 20, 25, 30, and 35 birds/m2). The results showed that ADG and ADFI were reduced (P < 0.05) as stocking density increased from 15 to 35 birds/m2, but increasing stocking density did not influence (P > 0.05) feed conversion ratio (FCR) and body measurement traits. High stocking density significantly decreased (P < 0.05) the feather quality of back, thoracoabdominal, wing, and tail. No significant difference (P > 0.05) was found in serum concentration of adrenocorticotrophic hormone, cortisol, corticosterone, triiodothyronine, and thyroxine. The weight of cecum and intestine decreased (P < 0.05) as the stocking density increased. Increasing stocking density decreased (P < 0.05) jejunal villus height and villus height-to-crypt depth ratio, and increased (P < 0.05) jejunal crypt depth and ileal crypt depth in geese. Consequently, the high stocking density could depress the growth and impaired feather quality and intestinal development of geese. Under our experimental conditions, we recommend that the stocking density of geese from 1 to 14 d of age should not more than 20 birds/m2.


Assuntos
Plumas , Gansos , Criação de Animais Domésticos , Animais , Galinhas , Dieta , Tri-Iodotironina
8.
J Vet Med Sci ; 83(10): 1582-1589, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34470973

RESUMO

Marek's disease virus (MDV) is an oncogenic alphaherpesvirus that causes immunosuppression, T-cell lymphomas, and neuropathic disease in infected chickens. To protect chickens from MDV infection, an avirulent live vaccine of turkey herpesvirus (HVT) has been successfully used for chickens worldwide. Similar to MDV for natural infection in both chickens and turkeys, HVT also infects lung in the early stage of infection and then lymphocytes from lymphoid organs. Virus replication requires cell-to-cell contact for spreading and semi-productive lytic replication in T and B cells. Then, cell-free infectious virions matured in the feather follicle epithelium (FFE) are released and spread through the feather from infected turkeys or chickens. To understand the lifecycle of HVT in inoculated chickens via the subcutaneous route, we investigate the replication kinetics and tissue organ tropism of HVT in chickens by a subcutaneous inoculation which is a major route of MDV vaccination. We show that the progeny virus matured in lymphocytes from the thymus, spleen, and lung as early as 2 days post-infection (dpi) and bursa of Fabricius at 4 dpi, whereas viral maturation in the FFE was observed at 6 dpi. Furthermore, semi-quantitative reverse transcription-PCR experiments to measure viral mRNA expression levels revealed that the higher expression levels of the late genes were associated with viral maturation in the FFE. These data that tropism and replication kinetics of HVT could be similar to those of MDV through the intake pathway of natural infection from respiratory tracts.


Assuntos
Plumas , Herpesvirus Meleagrídeo 1 , Animais , Galinhas , Epitélio , Cinética
9.
Sci Rep ; 11(1): 17499, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34471152

RESUMO

Maternal effects can shape the phenotypes of offspring, but the extent to which a layer breeder's experience can affect commercial laying hens remains unclear. We aimed to investigate the effects of maternal age and maternal environment on laying hens' behaviour and stress response. In our first experiment (E1), commercial hybrid hens were reared either in aviary or barren brooding cages, then housed in aviary, conventional cages or furnished (enriched) cages, thus forming different maternal housing treatments. Hens from each treatment were inseminated at three ages, and measures of response to manual restraint and social stress were assessed in offspring. In experiment 2 (E2), maternal age effects on offsprings' stress response were further investigated using fertile eggs from commercial breeder flocks at three ages. In E1, maternal age affected struggling and corticosterone during manual restraint, feather pecking and pulling and comb wounds. Additionally, maternal rearing and housing in aviary systems showed positive effects on measures of behaviour and stress response in offspring. Effects of maternal age were not replicated in E2, possibly due to methodological differences or higher tolerance to maternal effects in commercial breeders. Overall, we recommend researchers report parent stock age to increase comparison across studies and thus our understanding of maternal age effects.


Assuntos
Comportamento Animal/fisiologia , Meio Ambiente , Plumas/fisiologia , Idade Materna , Comportamento Social , Estresse Psicológico , Criação de Animais Domésticos , Animais , Animais Recém-Nascidos , Galinhas , Ovos , Feminino , Masculino , Restrição Física
10.
Biol Lett ; 17(8): 20210190, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34428957

RESUMO

Hummingbirds are perhaps the most exquisite bird species because of their prominent iridescence, created by stacks of melanosomes in the feather barbules. The feather colours crucially depend on the nanoscopic dimensions of the melanosome, and the displayed iridescence can distinctly vary, dependent on the spatial organization of the barbs and barbules. We have taken the genus Coeligena as a model group, with species having feathers that strongly vary in their spatial reflection properties. We studied the feather morphology and the optical characteristics. We found that the coloration of Coeligena hummingbirds depends on both the Venetian-blind-like arrangement of the barbules and the V-shaped, angular arrangement of the barbules at opposite sides of the barbs. Both the nanoscopic and microscopic organization of the hummingbird feather components determine the bird's macroscopic appearance.


Assuntos
Plumas , Iridescência , Animais , Aves
11.
Development ; 148(18)2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34344024

RESUMO

How dermis maintains tissue homeostasis in cyclic growth and wounding is a fundamental unsolved question. Here, we study how dermal components of feather follicles undergo physiological (molting) and plucking injury-induced regeneration in chickens. Proliferation analyses reveal quiescent, transient-amplifying (TA) and long-term label-retaining dermal cell (LRDC) states. During the growth phase, LRDCs are activated to make new dermal components with distinct cellular flows. Dermal TA cells, enriched in the proximal follicle, generate both peripheral pulp, which extends distally to expand the epithelial-mesenchymal interactive interface for barb patterning, and central pulp, which provides nutrition. Entering the resting phase, LRDCs, accompanying collar bulge epidermal label-retaining cells, descend to the apical dermal papilla. In the next cycle, these apical dermal papilla LRDCs are re-activated to become new pulp progenitor TA cells. In the growth phase, lower dermal sheath can generate dermal papilla and pulp. Transcriptome analyses identify marker genes and highlight molecular signaling associated with dermal specification. We compare the cyclic topological changes with those of the hair follicle, a convergently evolved follicle configuration. This work presents a model for analyzing homeostasis and tissue remodeling of mesenchymal progenitors.


Assuntos
Galinhas/fisiologia , Derme/fisiologia , Células Epidérmicas/fisiologia , Plumas/fisiologia , Folículo Piloso/fisiologia , Regeneração/fisiologia , Células-Tronco/fisiologia , Animais , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Cabelo/fisiologia , Muda/fisiologia , Transdução de Sinais/fisiologia
12.
J R Soc Interface ; 18(181): 20210252, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34343456

RESUMO

The diverse colours of bird feathers are produced by both pigments and nanostructures, and can have substantial thermal consequences. This is because reflectance, transmittance and absorption of differently coloured tissues affect the heat loads acquired from solar radiation. Using reflectance measurements and heating experiments on sunbird museum specimens, we tested the hypothesis that colour and their colour producing mechanisms affect feather surface heating and the heat transferred to skin level. As predicted, we found that surface temperatures were strongly correlated with plumage reflectivity when exposed to a radiative heat source and, likewise, temperatures reached at skin level decreased with increasing reflectivity. Indeed, nanostructured melanin-based iridescent feathers (green, purple, blue) reflected less light and heated more than unstructured melanin-based colours (grey, brown, black), as well as olives, carotenoid-based colours (yellow, orange, red) and non-pigmented whites. We used optical and heat modelling to test if differences in nanostructuring of melanin, or the bulk melanin content itself, better explains the differences between melanin-based feathers. These models showed that the greater melanin content and, to a lesser extent, the shape of the melanosomes explain the greater photothermal absorption in iridescent feathers. Our results suggest that iridescence can increase heat loads, and potentially alter birds' thermal balance.


Assuntos
Plumas , Passeriformes , Animais , Cor , Iridescência , Pigmentação
13.
Ecotoxicology ; 30(9): 1929-1940, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34383236

RESUMO

Saltmarsh sparrows (Ammospiza caudacuta) and seaside sparrows (A. maritima) are species of conservation concern primarily due to global sea-level rise and habitat degradation. Environmental mercury (Hg) contamination may present additional threats to their reproductive success and survival. To assess site-specific total mercury (THg) exposure and identify environmental correlates of THg detection, we sampled blood from adult male saltmarsh and seaside sparrows at 27 sites between Maine and Virginia, USA. The mean THg concentration (±1 SD) throughout the entire sampling range was 0.531 ± 0.287 µg/g wet weight (ww) for saltmarsh sparrows and 0.442 ± 0.316 µg/g ww for seaside sparrows. Individual THg concentrations ranged from 0.135-1.420 µg/g ww for saltmarsh sparrows and 0.153-1.530 µg/g ww for seaside sparrows. Model averaging from a suite of linear mixed models showed that saltmarsh sparrows averaged 20.1% higher blood THg concentrations than seaside sparrows, potentially due to differences in diet or foraging behavior. We found no evidence for a relationship between sparrow THg concentrations and land cover surrounding sampled marshes or average precipitation-based Hg deposition. Overall, our results suggest considerable, unexplained variation in tidal marsh sparrow blood THg concentrations over their co-occurring breeding ranges.


Assuntos
Poluentes Ambientais , Mercúrio , Pardais , Animais , Monitoramento Ambiental , Poluentes Ambientais/análise , Plumas/química , Masculino , Mercúrio/análise , New England , Áreas Alagadas
14.
Sci Total Environ ; 791: 148322, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34412380

RESUMO

It remains unclear how sub-lethal effects of contaminants play out in relation to other stressors encountered by free-ranging populations. Effects may be masked or influenced by interactions with field stressors such as food availability. We predicted that (1) including food availability, and particularly its interaction with Hg, would reveal or enhance associations between Hg and breeding endpoints. We further predicted that (2) breeding impairment associated with Hg would be higher under food stress conditions. We monitored Hg and nest success of great egrets (Ardea alba) in eight breeding colonies in the Florida Everglades over 11 years. We characterized variation in local food availability among colonies and years using fish biomass and recession range -a proxy to fish vulnerability. We used two Hg exposure indicators (egg albumen Hg and nestling feather Hg) and six breeding endpoints (clutch-size, brood-size, fledged-size, hatching success, post-hatching success and fledglings per egg) to assess whether variation in food availability influenced associations between Hg and these endpoints. Accounting for interactions between Hg and food availability, we identified statistically significant associations in all 12 indicator-endpoint combinations, while only three were detectable without food. Further, 10 combinations showed interactions between Hg and components of food availability. Our results also indicated an endpoint-specific affinity, with albumen [Hg] explaining more variation in hatching success while nestling feather [Hg] explained more variation in post-hatching survival. Both Hg indicators accounted for relevant (6-10%) amounts of variation in fledglings produced per egg laid, an integrative endpoint. Increased Hg exposure resulted in overall reduced reproductive success when food availability was low, but our models predicted low or no effects of increasing Hg exposure when food availability was high. Our results indicate that Hg induced impairment is strongly driven by food availability, providing a framework that accommodates previously contradictory results in the literature.


Assuntos
Aves , Mercúrio , Animais , Plumas , Alimentos , Reprodução
15.
PLoS One ; 16(7): e0253469, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34242251

RESUMO

The endangered Black-faced Spoonbill (Platalea minor) strictly breeds in marine environments and is threatened by the rapid loss of coastal wetlands within its breeding range. Adults with chicks are thought to gradually switch feeding sites from freshwater wetlands to coastal mudflats as the chicks' osmoregulatory system develops. We investigated age-dependent shifts in the diet of Black-faced Spoonbill chicks at four breeding colonies with varying freshwater habitat availability by examining stable isotopes (δ13C, δ15N) between the tip (grown at the age of 10 days) and middle (grown at the age of 22 days) portions of their primary feathers. The δ13C value of the middle portions was significantly higher than that of the tips, which suggested that the ratio of marine resources increased with the growth and development of chicks. A Bayesian isotope mixing model revealed that the diet proportion of marine prey in the early-chick rearing season was slightly higher than in the late-chick rearing season at three colonies in inshore areas, although this proportion was approximately 60% even in the early chick-rearing period. In contrast, isotopic values and reconstructed diet composition suggested that chicks in an offshore colony with limited freshwater wetlands relied more heavily on freshwater diets for both chick-rearing periods (>80%). Our results suggest that the shifts in feeding sites seen in previous studies might be related to the age-dependent dietary shift of chicks, highlighting the importance of freshwater wetlands for spoonbills on offshore islands without an inflow of freshwater in nearby intertidal mudflats. These findings emphasize the importance of freshwater prey and wetlands even for the endangered marine-breeding spoonbills, even though the negative impact of salt stress remains inconclusive.


Assuntos
Aves/fisiologia , Animais , Teorema de Bayes , Doenças das Aves/fisiopatologia , Dieta , Ecossistema , Meio Ambiente , Plumas/fisiologia , Áreas Alagadas
16.
Poult Sci ; 100(9): 101327, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34329988

RESUMO

Adequate pullet nutrition is essential to reach BW and suitable body composition for reproduction. An experiment was conducted to determine the effects of 4 dietary amino acid (AA) levels on BW, flock uniformity, body conformation, organ, leg, and feathering development of broiler breeder pullets during the rearing phase from 5 to 24 wk. A total of 1,360 Cobb-500 slow-feathering (SF) pullets were randomly placed in 16-floor pens with 85 females per pen. Diets with corn, soybean meal, and wheat-midds were formulated without protein restriction maintaining minimum ratios between essential AA and Lys on a digestible (dig) ideal basis. Treatments consisted of 4 dietary AA levels with 80% (low-AA), 90% (moderate-AA), 100% (standard-AA), and 110% (high-AA) of the Cobb-Vantress recommendations guided by dig Lys using balanced protein. Up to 4 wk, all pullets were fed a common starter crumble diet. Grower and developer mash diets were fed to pullets from 5 to 15 wk and from 16 to 24 wk, respectively. Pullets fed standard-AA and high-AA diets were heavier (P < 0.001) than those fed low-AA diets at 10, 15, and 20 wk of age. High-AA diets resulted in better (P = 0.040) flock uniformity at 10 wk. Pullets fed a high-AA diet had the highest (P = 0.041) relative breast weight at 20 wk of age and the lowest (P = 0.044) deposits of abdominal fat at 15 wk of age. Fleshing increased (P < 0.05) as AA content rise in the diet, while the relative shank length (P < 0.001) and the number of wing juvenile feathers (P = 0.004) decreased. Pullets fed the lowest dietary AA level had the longest (P = 0.007) small intestine relative to BW at 10 wk of age, but a smaller (P = 0.001) liver than those fed moderate and standard-AA diets at 20 wk of age. Dietary AA levels have important effects on pullet BW, fleshing, and organ development during rearing with potential reproductive performance impacts.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Galinhas , Aminoácidos , Ração Animal/análise , Animais , Peso Corporal , Dieta/veterinária , Plumas , Feminino
17.
Poult Sci ; 100(9): 101361, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34320452

RESUMO

The measurement of feather corticosterone concentrations (fCORT) is a comparatively new method for the evaluation of stress in wild and captive birds and may be a useful indicator in animal welfare research. The aim of this study was to assess the suitability of fCORT as an indicator of stress, and for this purpose a prolonged stress period was experimentally simulated by oral intake of corticosterone via drinking water and corticosterone concentrations were analyzed in feathers grown during this period. Layer pullets of both a control group (n = 20) and a CORT group (n = 20) were offered drinking water ad libitum throughout the entire experimental phase. The drinking water of the CORT group was supplemented with corticosterone at a concentration of 20 mg/l from the 64th to the 114th day of life. The vaned parts of the primaries 5 (P5s) were clipped on d 114 and fCORT was analyzed by ELISA after extraction. Body weights increased from day 64 until d 114 in both groups, however, at the end of the experiment, mean body mass in the CORT group was significantly lower than in the control group (P < 0.001). Pullets of the CORT group also showed shorter and lighter P5s as well as a retarded molt of the primaries. The supplementation of drinking water with corticosterone increased the average fCORT in the P5s of the CORT pullets compared with the control group (median: 110.3 pg/mm [interquartile range (IQR): 47.2] vs. 10.0 pg/mm [IQR: 2.5], P < 0.001). The results show that experimentally increased systemic corticosterone concentrations over a period of seven weeks in layer pullets are reflected in corticosterone concentrations of feathers grown during that time. This indicates that the measurement of fCORT may be a useful and minimally invasive tool for the evaluation of long-term stress in chicken and provides the basis for further investigations on its use in animal welfare research.


Assuntos
Água Potável , Plumas , Animais , Galinhas , Corticosterona , Suplementos Nutricionais , Feminino
18.
Poult Sci ; 100(9): 101360, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34320453

RESUMO

Under commercial conditions turkeys are housed in large groups in poorly structured environments. This leads to stress and subsequently to pecking and cannibalism. Environmental enrichment is suggested to reduce stress and feather pecking, thus leading to an increase of the overall flock health. However, the effect of increasing age on the use of enrichment elements and on the behavior repertoire as well as its correlation with health parameters has scarcely been studied. Therefore, our objective was to investigate the influence of environmental enrichment on the behavioral repertoire and on health parameters of turkeys. In 3 consecutive trials, female turkeys were housed up to 12 wk either in an unstructured (control group) or enriched environment (EE group) featuring elevated plateaus at different levels ("turkey tree"). Behavior parameters, clinical health, and immune parameters were determined at selected time points. The percentage of birds using the turkey tree increased with age up to 55 to 77% at 22 to 30 d post hatch (dph). Thereafter, the number of birds located on the turkey tree decreased to 25 to 32% at 73 to 79 dph. Feather pecking and fighting was significantly lower in the EE group compared to the control group in 2 and 3 trials, respectively (P < 0.05). The integrity of feathers and integument, scored in the head/neck, wing, and tail regions was repeatedly better in the EE birds compared to control birds at most investigated time points (P < 0.05), suggesting a reduction in stress related aggression by the use of the turkey tree. Head pecking, running and flying activity, foraging, and preening were overall comparable between the EE and the control group (P > 0.05). Humoral immunity as determined by vaccination-induced anti-Newcastle disease virus antibody titers was not affected by the turkey tree use. The flow cytometric evaluation of blood monocyte and T-lymphocyte numbers showed no repeatable difference between control and EE groups. Interestingly, compared to the control groups, EE birds displayed significantly higher numbers of circulating MHC class II+ lymphocytes and lower numbers of thrombocytes at various time points compared to controls (P < 0.05). This study provides clear evidence that environmental enrichment with plateaus not only leads to an altered behavioral repertoire but also modifies some of the investigated immune parameters, implying that EE may have a modulatory effect on turkeys' immunity and overall fitness. Further studies are needed to understand the correlation between behavior and health parameters in birds more closely.


Assuntos
Abrigo para Animais , Perus , Animais , Comportamento Animal , Galinhas , Plumas , Feminino , Contagem de Leucócitos/veterinária
19.
Integr Comp Biol ; 61(3): 1111-1121, 2021 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-34272860

RESUMO

Urbanization drives phenotypic variation in many animal species. This includes behavioral and physiological traits such as activity patterns, aggression, and hormone levels. A current challenge of urban evolutionary ecology is to understand the environmental drivers of phenotypic variation in cities. Moreover, do individuals develop tolerance to urban environmental factors, which underlie adaptative responses and contribute to the evolution of urban populations? Most available evidence comes from correlative studies and rare experiments where a single urban-related environmental factor has been manipulated in the field. Here we present the results of an experiment in which we tested for differences in the glucocorticoid (CORT) response of urban and rural blue tits nestlings (Cyanistes caeruleus) to artificial light at night (ALAN). ALAN has been suggested to alter CORT response in several animal species, but to date no study has investigated whether this effect of ALAN differs between urban and rural populations. Immediately after hatching, urban and forest broods were either exposed to 2 lux of ALAN (using an LED source mounted inside the nestbox) or received no treatment (dark control). The experiment lasted until the chicks fledged. When the chicks were 13 days old plasma samples were collected to measure baseline CORT concentrations, and feather samples to provide an integrative measure of CORT during growth. Forest birds had higher plasma CORT (pCORT) concentrations than their urban counterparts, irrespective of whether they were exposed to ALAN or not. Conversely, we found population-specific responses of feather CORT to ALAN. Specifically, urban birds that received ALAN had increased feather CORT compared with the urban dark controls, while the opposite was true for the forest birds. pCORT concentrations were negatively associated to fledging success, irrespective of population and treatment, while feather CORT was positively associated to fledging success in broods exposed to ALAN, but negatively in the dark control ones. Our results demonstrate that ALAN can play a role in determination of the glucocorticoid phenotype of wild animals, and may thus contribute to phenotypic differences between urban and rural animals.


Assuntos
Plumas , Glucocorticoides/química , Luz , Aves Canoras , Animais , Cidades , Poluição Ambiental , Plumas/química , Plumas/efeitos da radiação , Florestas , Glucocorticoides/sangue
20.
Braz J Biol ; 83: e246389, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34320050

RESUMO

Poultry industry is expanding rapidly and producing million tons of feather waste annually. Massive production of keratinaceous byproducts in the form of industrial wastes throughout the world necessitates its justified utilization. Chemical treatment of keratin waste is proclaimed as an eco-destructive approach by various researchers since it generates secondary pollutants. Keratinase released by a variety of microbes (bacteria and fungi) can be used for the effective treatment of keratin waste. Microbial degradation of keratin waste is an emerging and eco-friendly approach and offers dual benefits, i.e., treatment of recalcitrant pollutant (keratin) and procurement of a commercially important enzyme (keratinase). This study involves the isolation, characterization, and potential utility of fungal species for the degradation of chicken-feather waste through submerged and solid-state fermentation. The isolated fungus was identified and characterized as Aspergillus (A.) flavus. In a trial of 30 days, it was appeared that 74 and 8% feather weight was reduced through sub-merged and solid-state fermentation, respectively by A. flavus. The pH of the growth media in submerged fermentation was changed from 4.8 to 8.35. The exploited application of keratinolytic microbes is, therefore, recommended for the treatment of keratinaceous wastes to achieve dual benefits of remediation.


Assuntos
Galinhas , Plumas , Animais , Fermentação , Fungos , Resíduos Industriais , Queratinas/metabolismo
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