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1.
J Med Case Rep ; 17(1): 363, 2023 Aug 15.
Article in English | MEDLINE | ID: mdl-37580791

ABSTRACT

INTRODUCTION: Hydrocele, an abnormal fluid collection between parietal and visceral layers of the tunica vaginalis, is the commonest cause of scrotal swelling, and it affects all age groups. Calcification of hydrocele sac/wall is a rare clinical entity. The etiology of calcification of hydrocele sac is not clear, but most literature proposes that calcification is secondary to chronic irritation. Trauma and infectious diseases including Schistosoma haematobium, filariasis, and tuberculosis can also cause calcification of the hydrocele sac. CASE PRESENTATION: A 74-year-old Ethiopian male patient presented with left side scrotal swelling of 3 years duration, which was initially small but progressively increased. He had no history of trauma, and he had no history of swelling on the contralateral side. Scrotal ultrasound (US) showed a large echodebrinous left-side scrotal collection with calcifications, bilateral testis appear normal in size, echogenicity, and color Doppler flow with the index of likely chronic hematocele. Therefore, with a diagnosis of left-sided calcified hydrocele, the patient was operated on and the calcified sac was excised and sent for histopathology. Finally, the patient was discharged improved after 2 days of hospital stay. CONCLUSION: Calcification of the tunica vaginalis is very rare and is probably due to chronic irritation of the wall from the coexisting hydrocele. Surgical excision of calcified hydrocele sac is the treatment of choice.


Subject(s)
Calcinosis , Genital Diseases, Male , Testicular Hydrocele , Humans , Male , Animals , Aged , Egg Shell/pathology , Testicular Hydrocele/complications , Testicular Hydrocele/diagnostic imaging , Testicular Hydrocele/surgery , Genital Diseases, Male/complications , Scrotum/diagnostic imaging , Scrotum/pathology , Testis/pathology , Calcinosis/complications , Calcinosis/diagnostic imaging , Calcinosis/surgery , Inflammation/complications
2.
J Toxicol Sci ; 45(3): 131-136, 2020.
Article in English | MEDLINE | ID: mdl-32147636

ABSTRACT

Reproductive disorders in birds are the most characteristic effects of DDT contamination of wildlife. Experimental exposure of avian eggs to the estrogenic substance o,p'-DDT causes abnormal development of the reproductive tract (shortening of the left oviduct and aberrant development of the right oviduct) and eggshell thinning in mature birds, but it is still not known how eggshell thinning occurs in the abnormal oviduct. To fill this information gap, we examined the histology of the uterine part of the oviduct in Japanese quail treated in ovo with o,p'-DDT or a synthetic estrogen, diethylstilbestrol (DES), and we performed immunohistochemical staining for the calcium-binding proteins CALB1, SPP1, and TRPV6. Both o,p'-DDT-treated and DES-treated quail had few, and scattered, gland cells in the left uterus, unlike vehicle controls, in which gland cells tightly occupied the lamina propria. The aberrantly developed right uterus retained all the components of the normal left uterus, but in immature form. Immunostaining for CALB1, SPP1, and TRPV6 was greatly reduced by both o,p'-DDT and DES; SPP1 and TRPV6 immunostaining patterns, in particular, differed distinctly from those in the controls. These findings suggest that CALB1, SPP1, and TRPV6 are molecular factors, decreased production of which is responsible for eggshell thinning. Our findings also could contribute to understanding of the eggshell formation mechanism in birds.


Subject(s)
Calcium-Binding Proteins/metabolism , DDT/toxicity , Egg Shell/drug effects , Oviducts/drug effects , Oviducts/metabolism , Animals , Coturnix , Diethylstilbestrol/toxicity , Egg Shell/pathology , Female , Oviducts/pathology
3.
Avian Pathol ; 48(2): 98-110, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30484684

ABSTRACT

An outbreak of low pathogenic avian influenza (LPAI) subtype H6N1 (intravenous pathogenicity index = 0.11) infection occurred in four productive brown layer flocks on three farms in the Netherlands within a period of two months. The farms were located at a maximum distance of 4.6 km from each other. The infections were associated with egg production drops up to 74%, pale eggshells and persisting high mortality up to 3.2% per week. Three flocks were slaughtered prematurely as they were not profitable anymore. Newcastle disease, infectious bronchitis, egg drop syndrome and Mycoplasma gallisepticum infections could very likely be excluded as cause of or contributor to the condition in the field. Also, the anticoccidial drug nicarbazin, which can cause egg production drops and eggshell decolouration, was not detected in eggs from affected flocks. Furthermore, post mortem examinations revealed no lesions indicative of bacterial infection. Moreover, bacteriological analysis of hens was negative. The condition was reproduced in commercial brown layers after intratracheal inoculation with virus isolates from affected flocks. It is concluded that the LPAI H6N1 virus is very likely the only cause of the disease. An overview of main manuscripts published since 1976 describing non-H5 and non-H7 avian influenza (AI) virus infections in chickens and their biological significance is included in the present study, in which once more is shown that not only high pathogenic AI virus subtypes H5 and H7 can be detrimental to flocks of productive layers, but also non-H5 and non-H7 LPAI viruses (H6N1 virus). RESEARCH HIGHLIGHTS LPAI H6N1 can be detrimental to productive layers Detrimental effects are severe egg drop and persistent high mortality LPAI H6N1 virus outbreak seems to be self-limiting.


Subject(s)
Chickens/virology , Disease Outbreaks/veterinary , Influenza A virus/pathogenicity , Influenza in Birds/epidemiology , Poultry Diseases/epidemiology , Animals , Egg Shell/pathology , Eggs , Female , Influenza in Birds/mortality , Influenza in Birds/pathology , Influenza in Birds/virology , Netherlands/epidemiology , Poultry Diseases/mortality , Poultry Diseases/pathology , Poultry Diseases/virology
4.
Viruses ; 10(8)2018 08 18.
Article in English | MEDLINE | ID: mdl-30126175

ABSTRACT

A disease with a sudden drop in egg production and shell-less eggs called, shell-less egg syndrome (SES) has been observed in Western Canada egg layer flocks since 2010. The etiology of this disease is not known. We hypothesize that SES is caused by an infectious bronchitis virus (IBV) strain since it is known that IBV replicates in the shell gland causing various eggshell abnormalities. In this study, we screened egg layer flocks, in the provinces of Alberta (AB) and Saskatchewan (SK), with and without a history of SES for the presence of IBV infection. During 2015⁻2016, a total of 27 egg layer flocks were screened in AB (n = 7) and SK (n = 20). Eighty-one percent of the screened flocks (n = 22) were positive for IBV infection. Thirty of these isolates were successfully characterized using molecular tools targeting the most variable spike (S) 1 gene. IBV isolates from this study clustered into three genotypes based on partial S1 gene variability. The majority of the IBV isolates (70%) were Massachusetts (Mass) type, and the rest were either Connecticut (Conn) type or an uncharacterized genotype with genetic characteristics of Mass and Conn types. Since the majority of the IBV isolates included within the Mass type, we used a Mass type IBV isolate to reproduce SES in specific pathogen free (SPF) white leghorn chickens in lay. Further studies are warranted to investigate whether other IBV isolates can cause SES, to clarify the pathogenesis of SES and to develop a vaccine in order to prevent SES as observed in Western Canadian layer flocks.


Subject(s)
Coronavirus Infections/veterinary , Egg Shell/virology , Infectious bronchitis virus/genetics , Poultry Diseases/epidemiology , Spike Glycoprotein, Coronavirus/genetics , Zygote/virology , Animals , Canada/epidemiology , Chickens , Coronavirus Infections/epidemiology , Coronavirus Infections/transmission , Coronavirus Infections/virology , Egg Shell/pathology , Farms , Female , Gene Expression , Genotype , Infectious bronchitis virus/classification , Infectious bronchitis virus/isolation & purification , Infectious bronchitis virus/pathogenicity , Phylogeny , Poultry Diseases/transmission , Poultry Diseases/virology , Specific Pathogen-Free Organisms , United States/epidemiology , Zygote/pathology
5.
PLoS One ; 12(3): e0164823, 2017.
Article in English | MEDLINE | ID: mdl-28273082

ABSTRACT

Ancient DNA (aDNA) analysis of extinct ratite species is of considerable interest as it provides important insights into their origin, evolution, paleogeographical distribution and vicariant speciation in congruence with continental drift theory. In this study, DNA hotspots were detected in fossilized eggshell fragments of ratites (dated ≥25000 years B.P. by radiocarbon dating) using confocal laser scanning microscopy (CLSM). DNA was isolated from five eggshell fragments and a 43 base pair (bp) sequence of a 16S rRNA mitochondrial-conserved region was successfully amplified and sequenced from one of the samples. Phylogenetic analysis of the DNA sequence revealed a 92% identity of the fossil eggshells to Struthio camelus and their position basal to other palaeognaths, consistent with the vicariant speciation model. Our study provides the first molecular evidence for the presence of ostriches in India, complementing the continental drift theory of biogeographical movement of ostriches in India, and opening up a new window into the evolutionary history of ratites.


Subject(s)
DNA, Ancient/analysis , Struthioniformes/genetics , Animals , Egg Shell/metabolism , Egg Shell/pathology , Fossils , India , Microscopy, Confocal , Mitochondria/genetics , Phylogeny , RNA, Ribosomal, 16S/chemistry , RNA, Ribosomal, 16S/genetics , RNA, Ribosomal, 16S/metabolism , Sequence Analysis, DNA , Struthioniformes/classification
6.
Theriogenology ; 91: 62-68, 2017 Mar 15.
Article in English | MEDLINE | ID: mdl-28215687

ABSTRACT

The aim of this study was to determine the mechanism by which Newcastle disease virus (NDV) affects eggshell quality. Thirty-week-old specific pathogen free (SPF) egg-laying hens were inoculated with the velogenic genotype VIId NDV strain (infected group) or with inoculating media without virus (control group) by combined intraocular and intranasal routes. The levels of CaBP-D28k mRNA expression in the uterus, a gene related to eggshell quality, were examined by quantitative reverse transcriptase polymerase chain reaction (RT-PCR). The quality of eggshells was analyzed by scanning electron microscopy (SEM). The infected group showed a marked decline in egg production when compared to the control group. The NDV antigen was found more abundantly in the glandular epithelium of the infected hens' uteri from 1 to 15 d post-inoculation (dpi). The levels of CaBP-D28k mRNA expression in the uteri of infected hens were significantly lower than in the control hens from 3 to 15 dpi (P < 0.05). The changes in the Ca concentrations in the eggshells were consistent with the expression of CaBP-D28k mRNA in the infected hens. Ultrastructural examination of eggshells showed significantly reduced shell thickness in the infected hens from 1 to 15 dpi (P < 0.05). Furthermore, obvious changes in the structure of the external shell surface and shell membrane were detected in the infected hens compared with the control hens. In conclusion, the current study confirmed that velogenic genotype VIId NDV infection is associated with the deterioration of the eggshell quality of the laying hens.


Subject(s)
Avian Proteins/metabolism , Calbindins/metabolism , Chickens/virology , Egg Shell/virology , Newcastle Disease/pathology , Animals , Avian Proteins/genetics , Calbindins/genetics , Calcium/metabolism , Egg Shell/pathology , Egg Shell/ultrastructure , Female , Microscopy, Electron, Scanning , Newcastle disease virus/genetics
7.
Avian Dis ; 60(4): 731-738, 2016 12.
Article in English | MEDLINE | ID: mdl-27902895

ABSTRACT

Fatigued walking condition (FWC) in ducks is an important welfare and processing issue during the loading/unloading to the processing plant that can be related to heart and bone development. An experiment was conducted to evaluate the effects of incubation conditions on duck embryo bone and heart development and their subsequent effects on ducks showing FWC at market age. Four groups of 2500 Pekin duck eggs were subjected to combinations of two incubation temperature profiles (elevated [E] and normal [N]) and two eggshell conductance profiles (G) (reduced [GR] and normal [GN]). At hatch 10 ducklings from each treatment combination were sampled for heart, liver, residual yolk, and total body weight as well as relative weights (organ percentage of whole body weight). Femur, tibia, and tarsus length and weight were also obtained, and relative asymmetry (RA) was calculated for each leg section. At 35 days of age during unloading of the truck at the slaughter plant, five hens and five drakes demonstrating normal walking and FWC were sampled. Body, heart, and ventricular weights were obtained along with femur, tibia and tarsus length, weight, and RA. Bone strength was evaluated using a three-point bending test, and tibia ash content was assessed. At hatch duckling bone characteristics and organ weights were found to be primarily affected by GR conditions, while heart development in older ducks was mainly impacted by E incubation temperatures. Tibia and relative weight at 35 days were also increased by GR and E. Fatigued ducks presented heavier tibias with more RA and cortical thickness but lower ash percentage. In conclusion, the changes in bone development during incubation and posthatch life were related to duck FWC presence during transportation to the processing plant.


Subject(s)
Poultry Diseases/pathology , Animals , Bone and Bones/embryology , Bone and Bones/pathology , Ducks/embryology , Egg Shell/chemistry , Egg Shell/embryology , Egg Shell/pathology , Female , Heart/embryology , Male , Poultry Diseases/embryology , Temperature
8.
Vet Res ; 47: 35, 2016 Feb 25.
Article in English | MEDLINE | ID: mdl-26915662

ABSTRACT

This study aimed to determine the mechanism by which H9N2 avian influenza virus (AIV) affects eggshell quality. Thirty-week-old specific pathogen free egg-laying hens were inoculated with the chicken-origin H9N2 AIV strain (A/Chicken/shaanxi/01/2011) or with inoculating media without virus by combined intraocular and intranasal routes. The time course for the appearance of viral antigen and tissue lesions in the oviduct was coincident with the adverse changes in egg production in the infected hens. The viral loads of AIV have a close correlation with the changes in the uterus CaBP-D28k mRNA expression as well as the Ca concentrations in the eggshells in the infected hens from 1 to 7 days post inoculation (dpi). Ultrastructural examination of eggshells showed significantly decreased shell thickness in the infected hens from 1 to 5 dpi (P < 0.05). Furthermore, obvious changes in the structure of the external shell surface and shell membrane were detected in the infected hens from 1 to 5 dpi as compared with the control hens. In conclusion, this study confirmed that H9N2 AIV strain (A/Chicken/shaanxi/01/2011) infection is associated with severe lesions of the uterus and abnormal expression of CaBP-D28k mRNA in the uteri of the infected hens. The change of CaBP-D28k mRNA expression may contribute to the deterioration of the eggshell quality of the laying hens infected with AIV. It is noteworthy that the pathogenicity of H9N2 AIV strains may vary depending on the virus strain and host preference.


Subject(s)
Chickens , Egg Shell/pathology , Influenza A Virus, H9N2 Subtype/physiology , Influenza in Birds/pathology , Poultry Diseases/pathology , Animals , Avian Proteins/genetics , Avian Proteins/metabolism , Calbindin 1/genetics , Calbindin 1/metabolism , Egg Shell/ultrastructure , Egg Shell/virology , Female , Gene Expression , Influenza in Birds/virology , Microscopy, Electron, Scanning/veterinary , Oviducts/virology , Poultry Diseases/virology
9.
Prev Vet Med ; 106(1): 75-8, 2012 Sep 01.
Article in English | MEDLINE | ID: mdl-22459486

ABSTRACT

Mycoplasma synoviae (M. synoviae) can cause respiratory disease, synovitis, or result in a silent infection in chickens and turkeys. The importance of M. synoviae is well established in broilers but only a few studies have been conducted in layers. In the present study, the prevalence of M. synoviae in commercial layer flocks was estimated using ELISA. For this study, 19 commercial layer flocks were selected randomly from New South Wales and Queensland region of Australia from producers who were willing to participate in the survey. Sixty eggs per flocks were randomly collected, out of these 30 eggs were used for ELISA and remaining 30 eggs were used to estimate various egg shell quality parameters. Subsequently, association between the serological status of eggs for M. synoviae and egg shell quality was studied. In the flocks under study, seroprevalence of M. synoviae was found to be high at 69% (95% confidence interval (CI)=41.3-89.0). Statistical analysis showed an association between serological status for M. synoviae and egg quality parameters such as translucency, shell breaking strength, % shell reflectivity and shell deformation. On the other hand, there was no significant association between serological status for M. synoviae and other egg quality parameters such egg weight, egg shell weight, % egg shell or shell thickness.


Subject(s)
Antibodies, Bacterial/blood , Chickens , Egg Shell/microbiology , Mycoplasma Infections/epidemiology , Mycoplasma synoviae/immunology , Poultry Diseases/epidemiology , Animals , Egg Shell/pathology , Enzyme-Linked Immunosorbent Assay/veterinary , Female , Mycoplasma synoviae/isolation & purification , New South Wales/epidemiology , Queensland/epidemiology , Seroepidemiologic Studies
11.
Avian Dis ; 54(2): 961-4, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20608549

ABSTRACT

Eggshell abnormalities were seen in the apex of eggs in two of three flocks of multi-age, Hy-Line layer chickens housed on a farm in Northern Italy. Approximately 1.3% to 1.8% of eggs in one flock were affected, amounting to 300-400 eggs per day; the abnormalities resulted in a great deal of breakage and spoilage of healthy eggs. The mean weight of eggs was also reduced. Egg abnormalities in a second flock were less severe. Mycoplasma synoviae was detected in birds from both of the affected flocks by serologic, cultural, and molecular techniques, but not in a third, adjacent flock where no eggshell abnormalities were seen. Treatment with tylosin, administered in the drinking water for 5 days, resulted in an immediate improvement of eggshell quality and egg weight. There was no evidence of infectious bronchitis virus in the flocks.


Subject(s)
Chickens , Egg Shell/pathology , Mycoplasma Infections/veterinary , Mycoplasma synoviae/isolation & purification , Oviposition , Tylosin/therapeutic use , Animals , Anti-Bacterial Agents/therapeutic use , Female , Mycoplasma Infections/drug therapy , Mycoplasma Infections/pathology
12.
Berl Munch Tierarztl Wochenschr ; 123(3-4): 111-8, 2010.
Article in German | MEDLINE | ID: mdl-20329643

ABSTRACT

Hens laying eggs with egg-pole shell defects (EPS) were examined in a clinical prospective study. 86 hens with EPS and 72 hens without EPS from three flocks were selected for this study. It could be proven serologically that hens with EPS had significant (p < 0.05) higher titers against Mycoplasma (M.) synoviae then hens without EPS. PCR tested cloacal swabs for M. synoviae were more frequently positive from hens with EPS (87%; n=72) then from hens without EPS (18%; n=13). Furthermore, M. synoviae could be cultivated from the oviduct of five hens with EPS. Additionally, M. synoviae-DNA was detectable in the albumen of nearly all eggs with EPS (n=48; 98%), contrary to the eggs without EPS (n=11; 26%). Ultrastructural investigation revealed that eggs with EPS showed considerable differences of the egg shell structure as well as the cross section dimension according to eggs without EPS. Due to the significantly more frequent detection of M. synoviae-DNA from the cloaca of chickens with EPS, is an involvement of M. synoviae in laying of EPS in the surveyed herds likely. Further infection experiments with the isolated M. synoviae were not perfomed, therefore about the causal pathogenic role of M. synoviae in the development of eggs with EPS in the surveyed herds can only be speculated.


Subject(s)
Chickens/microbiology , Egg Shell/microbiology , Mycoplasma synoviae/isolation & purification , Animals , Antibodies, Bacterial/blood , Egg Shell/pathology , Egg Shell/ultrastructure , Eggs/microbiology , Female , Microscopy, Electron, Scanning , Mycoplasma synoviae/immunology , Oviposition
13.
Ecotoxicology ; 18(7): 802-13, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19513829

ABSTRACT

Spatial and temporal assessments and reports of polybrominated diphenyl ether (PBDE) flame retardants in birds remain sparse. In the present study, PBDEs were detected in all 120 osprey (Pandion haliaetus) eggs collected. The eggs were collected from nests along the Columbia, Willamette and Yakima rivers of Oregon (OR) and Washington (WA) and in Puget Sound (WA) between 2002 and 2007. PBDE congeners: 17, 28, 47, 49, 66, 85, 99, 100, 138, 153, 154 (possible coelution with brominated biphenyl 153 [BB153]), 183, 190 (detected in one egg), 209 (not detected), and BB101 (only detected in 2006 and 2007) and total-alpha-hexabromocyclododecane (only detected in five eggs) were analyzed for in the egg samples. Eggs from reservoirs in the forested headwaters of the Willamette River (2002) contained the lowest concentrations of SigmaPBDEs (geometric mean [range], 98 [55.2-275] ng/g wet weight [ww]), while those from the middle Willamette River (2006) contained the highest (897 [507-1,880] ng/g ww). Concentrations in eggs from the Columbia River progressively increased downstream from Umatilla, OR (River Mile [RM] 286) to Skamokoa, WA (RM 29), which indicated additive PBDE sources along the river. In general, regardless of the year of egg collection, differences in PBDE concentrations reported in osprey eggs along the three major rivers studied (Columbia, Willamette and Yakima) seem to reflect differences in river flow (dilution effect) and the extent of human population and industry (source inputs) along the rivers. PBDE concentrations increased over time at two locations (Seattle, WA; Columbia River, RM 29-84) where temporal patterns could be evaluated. Only during 2006 (on the middle Willamette River, RM 61-157) and 2007 (on the lower Columbia River, RM 29-84) did SigmaPBDE concentrations in osprey eggs exceed 1,000 ng/g ww with negative relationships indicated at both locations between productivity and SigmaPBDE concentrations in eggs (P = 0.008, P = 0.057). Osprey eggs from Everett, WA contained nearly twice the SigmaPBDE concentration (geometric mean 239 vs. 141 ng/g ww, range 124-384 vs. 22.2-819 ng/g ww, P < or = 0.05) as double-crested cormorant (Phalacrocorax auritus) eggs collected at the same location and time, which is likely due to dietary differences. No significant relationship (all Ps > 0.147) was indicated between PBDE congeners (including SigmaPBDEs) and eggshell thickness at the concentrations observed in this study.


Subject(s)
Environmental Pollutants/toxicity , Falconiformes , Flame Retardants/toxicity , Halogenated Diphenyl Ethers/toxicity , Ovum/drug effects , Reproduction/drug effects , Animals , Egg Shell/drug effects , Egg Shell/pathology , Environmental Monitoring , Environmental Pollutants/analysis , Environmental Pollutants/metabolism , Flame Retardants/analysis , Flame Retardants/metabolism , Halogenated Diphenyl Ethers/analysis , Halogenated Diphenyl Ethers/metabolism , Oregon , Ovum/chemistry , Ovum/metabolism , Washington
14.
J Forensic Sci ; 53(3): 694-8, 2008 May.
Article in English | MEDLINE | ID: mdl-18471217

ABSTRACT

The following study examines the reliability of physically matching fragments of bone and other mineral-based biological materials such as shells and teeth. Participants with varying education, training, and experience were asked to complete a matching exercise consisting of intentionally fragmented specimens. Success rates were very high; the positive association (correct match) rate was 0.925, while the nonassociation (overlooked match) rate was 0.075, and negative associations (incorrect matches) occurred at a rate of just 0.001. Results also indicate that those with more education and related experience tended to have higher positive association rates, although not significant statistically. Experienced osteologists, however, completed the matching exercise in significantly less time. Low error rates among both experienced and inexperienced individuals support the reliability and validity of performing physical matches of these materials, and suggest that performance may also be related to an individual's aptitude for spatial tasks or other factors.


Subject(s)
Bone and Bones/pathology , Egg Shell/pathology , Forensic Anthropology , Tooth/pathology , Animals , Educational Status , Humans , Professional Competence , Time Factors
15.
Ecotoxicol Environ Saf ; 68(1): 79-83, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17081607

ABSTRACT

Contaminant analyses in animal eggs have illustrated the benefit of wildlife as indicators of xenobiotic contamination in natural habitats. In 2002, concentrations of 16 organochlorine insecticides were measured in egg yolk and the reproductive success of the little egret, Egretta garzetta, was studied in a population at Wat Tan-en non-hunting area Bang Pahan District, Phra Nakhorn Si Ayuthaya Province, Thailand. Only 4,4'-dichloro diphenylethane (4,4'-DDE) was detected in the yolk of all samples (n=12) at the concentrations ranging from 33.4 to 116.0 ng/gwetwt. Mean eggshell thickness (n=24) was 0.261+/-0.005 mm. Relationships between the concentrations of 4,4'-DDE and eggshell thickness as well as the reproductive success at all stages were not found (P>0.05). Rather, major factors potentially influencing the decline of reproductive success observed during the field study may include strong wind, predators, intraspecific and interspecific competitions.


Subject(s)
Birds/physiology , Egg Yolk/chemistry , Hydrocarbons, Chlorinated/analysis , Insecticides/analysis , Reproduction/physiology , Water Pollutants, Chemical/analysis , Animals , Clutch Size/drug effects , Dichlorodiphenyl Dichloroethylene/analysis , Dichlorodiphenyl Dichloroethylene/toxicity , Egg Shell/drug effects , Egg Shell/pathology , Environmental Monitoring , Female , Hydrocarbons, Chlorinated/toxicity , Insecticides/toxicity , Reproduction/drug effects , Thailand , Water Pollutants, Chemical/toxicity
16.
Poult Sci ; 85(11): 2001-8, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17032836

ABSTRACT

An experimental program of mechanical testing has shown that microcracks initiate in hens' eggs at loads less than that necessary to cause total structural failure. In contact loading, computational modeling and numerical analysis show that very high stress levels develop on the inner surface of the eggshell as it conforms to a hard contact surface. This causes a series of microcracks to initiate at the inner surface of the shell and radiate out from the load site. A series of concentric circumferential microcracks also develop beneath the cuticle from the edge of the contact zone. Calculations relating to the eggshells' dynamic response indicate that microcracks have a little effect on the structural stiffness and resonant frequencies of the egg. As a result, microcracks are unlikely to be detected by online crack detection systems, which rely on mechanical excitation. Eggs in retail outlets are likely to contain microcracks as a result of insults experienced during the collection, grading, and packing processes. Because the eggshell forms the first line of defense against potentially pathogenic microorganisms entering the egg contents, microcracks could potentially compromise egg safety.


Subject(s)
Egg Shell/ultrastructure , Eggs , Animals , Chickens , Consumer Behavior , Consumer Product Safety , Egg Shell/pathology , Eggs/standards , Female , Food Contamination/prevention & control , Microscopy, Electron, Scanning/veterinary , Oviposition , Stress, Mechanical , Tensile Strength
17.
Reproduction ; 128(4): 455-61, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15454640

ABSTRACT

Eggshell thinning among wild birds has been an environmental concern for almost half a century. Although the mechanisms for contaminant-induced eggshell thinning are not fully understood, it is generally conceived to originate from exposure of the laying adult female. Here we show that eggshell thinning in the domestic hen is induced by embryonic exposure to the synthetic oestrogen ethynyloestradiol. Previously we reported that exposure of quail embryos to ethynyloestradiol caused histological changes and disrupted localization of carbonic anhydrase in the shell gland in the adult birds, implying a functional disturbance in the shell gland. The objective of this study was to examine whether in ovo exposure to ethynyloestradiol can affect eggshell formation and quality in the domestic hen. When examined at 32 weeks of age, hens exposed to ethynyloestradiol in ovo (20 ng/g egg) produced eggs with thinner eggshells and reduced strength (measured as resistance to deformation) compared with the controls. These changes remained 14 weeks later, confirming a persistent lesion. Ethynyloestradiol also caused a decrease in the number of shell gland capillaries and in the frequency of shell gland capillaries with carbonic anhydrase activity. These data suggested that a disrupted carbonic anhydrase expression was involved in the mechanism for the oestrogen-induced eggshell thinning found in this study. The results support our hypothesis that eggshell thinning in avian wildlife can result from a structural and functional malformation in the shell gland, induced by xeno-oestrogen exposure during embryonic development.


Subject(s)
Carbonic Anhydrases/metabolism , Chickens/metabolism , Egg Shell/pathology , Estradiol Congeners/adverse effects , Ethinyl Estradiol/adverse effects , Prenatal Exposure Delayed Effects , Animals , Carbonic Anhydrases/analysis , Estradiol Congeners/pharmacology , Ethinyl Estradiol/pharmacology , Female , Histocytochemistry/methods , Image Processing, Computer-Assisted , Pregnancy
18.
Vaccine ; 21(21-22): 2761-6, 2003 Jun 20.
Article in English | MEDLINE | ID: mdl-12798616

ABSTRACT

In this study, the effectiveness of antibodies against the hexon, fiber or a fiber fragment of an avian adenovirus egg-drop syndrome (EDS), in neutralizing the virus was tested. The fiber protein is responsible for binding the virus to the target cell. The fiber fragment knob-s comprises the carboxy-terminal knob domain and 34 amino acids of the immediately adjacent shaft domain of the adenovirus fiber protein. The hexon, fiber capsid protein and knob-s were produced in E. coli and injected into chickens. Antibodies that were produced against the whole fiber protein showed some hemagglutination inhibition (HI) activity. Antibodies produced against the knob-s protein showed HI activity and serum neutralization (SN) activity similar to the positive control-whole virus vaccine. We assume that production of only part of the fiber enables the protein produced in E. coli to fold correctly. Antibodies produced against the hexon protein showed no SN activity. In summary, knob-s induced SN and HI antibodies against EDS virus at a rate similar to the whole virus and were significantly more efficient than the full-length fiber. The recombinant knob-s protein may be used as a vaccine against pathogenic adenovirus infections.


Subject(s)
Adenoviridae Infections/veterinary , Capsid Proteins/immunology , Egg Shell/pathology , Poultry Diseases/prevention & control , Viral Vaccines/immunology , Adenoviridae Infections/immunology , Adenoviridae Infections/prevention & control , Animals , Capsid Proteins/biosynthesis , DNA/genetics , Ducks , Escherichia coli/metabolism , Poultry Diseases/immunology , Recombinant Proteins/biosynthesis , Recombinant Proteins/immunology , Vaccination , Vaccines, Subunit/immunology
19.
Br Poult Sci ; 40(5): 585-91, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10670668

ABSTRACT

1. This study investigated relationships between the timing of stress, duration of oviposition delays and consequences for eggshell quality, in 2 experiments with ISA Brown hens. 2. Periods of up to 6 h of environmental stress (relocation from an individual cage to a larger one containing 3 unfamiliar hens), commencing up to 4.5 h before predicted oviposition time, reliably induced oviposition delays. Many hens still retained their egg when stress ended. 3. Ovipositions that occurred during stress were never delayed for more than 3.0 h beyond the expected time. Ovipositions that occurred after the period of stress ended usually did so after <1 h if the delay at the end of stress was less than about 2.4 h. Delays that ended either during stress or <2 h after stress ended were classified as short-term. 4. If an oviposition delay was more than about 2.4 h when stress ended, the egg concerned was usually laid much later, after a delay of 7 to 15 h. Delays that ended >5 h after stress ended were classified as long-term. 5. Eggs delayed long-term were white-banded and the subsequent egg was slab-sided, or occasionally soft-shelled. Short-term delays often caused eggshell dusting with varying amounts of superficial calcification. Hence, duration of oviposition delay affects both the number of abnormal eggshells and the degree of abnormality. 6. The present findings are of potential importance to both the egg industry and breeders, because abnormal eggshells cause downgrading and can impair embryonic development. Also, numbers of abnormal eggshells and degree of abnormality can be used as indicators of environmental stress.


Subject(s)
Chickens , Egg Shell/pathology , Oviposition , Poultry Diseases/pathology , Stress, Physiological/veterinary , Animals , Female , Poultry Diseases/physiopathology , Stress, Physiological/pathology , Stress, Physiological/physiopathology , Time Factors
20.
Onderstepoort J Vet Res ; 58(4): 309-10, 1991 Dec.
Article in English | MEDLINE | ID: mdl-1664076

ABSTRACT

A drop in egg production associated with loss of pigment and soft-shelled eggs was experienced on a farm in the Western Cape. Investigations revealed high levels of antibodies against adenovirus 127, the causative agent of egg drop syndrome (EDS) in chickens which were not vaccinated against EDS. A cytopathic agent was subsequently isolated in chicken embryo liver cell cultures and identified as EDS virus by haemagglutination inhibition and neutralization tests.


Subject(s)
Adenoviridae Infections/veterinary , Aviadenovirus/isolation & purification , Chickens , Poultry Diseases/microbiology , Adenoviridae Infections/microbiology , Animals , Egg Shell/pathology , South Africa , Syndrome
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