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First record of twin fetuses in a stranded Cuvier’s beakedwhale or goose-beaked whale(Ziphius cavirostris)
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作者 Angelico Jose C.Tiongson Jean Asuncion Utzurrum +1 位作者 Denzyl G.Divinagracia Jo Marie Acebes 《Current Zoology》 2025年第2期263-266,共4页
Cetaceans include the largest animals ever to have lived onearth and are uniparous(producing a single calf at each birth)across the infraorder.However,instances of multiple fetuseshave been observed naturally among un... Cetaceans include the largest animals ever to have lived onearth and are uniparous(producing a single calf at each birth)across the infraorder.However,instances of multiple fetuseshave been observed naturally among uniparous mammals,including cetaceans.Despite this,there is no known documented case of twins in cetaceans successfully carried to termin the wild(Perrin and Donovan 1984),and if such casesexist,they would be diffcult to detect. 展开更多
关键词 beaked whale CETACEANS marine mammals TWINNING ZIPHIIDAE
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Asymmetric expression of CA2 and CA13 linked to calcification in the bilateral mandibular condyles cause crossed beaks in chickens
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作者 Lei Shi Yanyan Sun +14 位作者 Yunlei Li Hao Bai Jingwei Yuan Hui Ma Yuanmei Wang Panlin Wang Aixin Ni Linlin Jiang Pingzhuang Ge Shixiong Bian Yunhe Zong Jinmeng Zhao Adamu MIsa Hailai HTesfay Jilan Chen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第7期2379-2390,共12页
Crossed beak is a complex mode of inheritance with prevalence ranging from 0.2 to 7.4% in at least 12 chicken strains worldwide.To reveal the intrinsic factors causing crossed beaks,genes expression patterns in bilate... Crossed beak is a complex mode of inheritance with prevalence ranging from 0.2 to 7.4% in at least 12 chicken strains worldwide.To reveal the intrinsic factors causing crossed beaks,genes expression patterns in bilateral mandibular condyle between affected and normal birds were characterized by RNA sequencing analysis in the present studies.Crossed beak was induced by short length of unilateral mandibular ramus,and a total of 110differentially expressed genes were up-or down-regulated in the affected(short)mandibular condyle side as compared to the normal side.Carbonic anhydrase 2(CA2)and Carbonic anhydrase 13(CA13)were enriched in the carbonate dehydratase activity,and high-expressed in mandibular condyle and osteoblasts(P<0.05).However,both were low-expressed in short mandibular condyle side of affected birds(P<0.05).The carbonate dehydratase inhibitor experiments confirmed that there is positive association between the calcification and carbonic anhydrase isoenzymes.Quantitative analysis with cetylpyridinium chloride showed a decrease in calcification when the cells were transfected with an anti-CA13 shRNA.Our research suggested that CA2 and CA13 are down-calcified in shortside mandibular condyle,and caused mandibular ramus to grow slowly.CA2 and CA13 have the critical role in crossed beaks by regulating calcification of mandibular condyle. 展开更多
关键词 CHICKEN crossed beak carbonic anhydrase CALCIFICATION CA2 CA13
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High Individual Variability in Beak Stable Isotopes of Jumbo Squid off Peruvian Exclusive Economic Zone(EEZ) Waters in the Analysis of Migratory and Foraging Ecology 被引量:5
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作者 LIU Bilin JIN Yue +4 位作者 CHEN Xinjun LI Jianhua QIAN Weiguo LIU Na HUAN Mengyao 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第1期232-238,共7页
Stable isotopes(δ^(13)C and δ^(15)N) have been widely used to track cephalopod habitat, migration and trophic structure. In this study, we analyzed the δ^(13)C and δ^(15)N values in 245 Dosidicus gigas beaks colle... Stable isotopes(δ^(13)C and δ^(15)N) have been widely used to track cephalopod habitat, migration and trophic structure. In this study, we analyzed the δ^(13)C and δ^(15)N values in 245 Dosidicus gigas beaks collected during 2009–2010 and in 2013 off Peruvian Exclusive Economic Zone(EEZ) waters. High individual variation in beak stable isotopes was shown with values ranging from-19.4‰ to-15.8‰ for δ^(13)C and from 5.0‰ to 15.1‰ for δ^(15)N. A generalized additive model(GAM) showed that latitude, mantle length and distance to shelf break significantly described the isotope variation with deviance ranging from 16.6% in δ^(13)C to 36.3% in δ^(15)N. Large variability in beak δ^(13)C values for a given size and sampling station indicated that D. gigas off the Peruvian EEZ waters migrate in different ways when they occupy a large range of habitats for their ontogeny. Low baseline δ^(15)N values suggested that spatial changes in diet trophic level may be the main determinative factor in beak δ^(15)N variation. We conclude that high variability in beak δ^(15)N values for a given set of explanatory variables indicated that D. gigas is an opportunistic predator with highly diverse dietary habitats. This study further develops our knowledge of the life history of D. gigas in such a highly dynamic region. 展开更多
关键词 isotopes variability TROPHIC level beak Dosidicus GIGAS Peru GAM
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Ontogenetic difference of beak elemental concentration and its possible application in migration reconstruction for Ommastrephes bartramii in the North Pacific Ocean 被引量:5
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作者 Zhou Fang Bilin Liu +1 位作者 Xinjun Chen Yong Chen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第10期43-52,共10页
The migration route of oceanic squid provides critical information for us to understand their spatial and temporal variations.Mark-recapture and electronic tags tend to be problematic during processing.Cephalopod hard... The migration route of oceanic squid provides critical information for us to understand their spatial and temporal variations.Mark-recapture and electronic tags tend to be problematic during processing.Cephalopod hard structures such as the beak,containing abundant ecological information with stable morphology and statolithlike sequences of growth increments,may provide information for studying spatio-temporal distribution.In this study,we developed a method,which is based on elemental concentration of beaks at different ontogenetic stages and sampling locations,to reconstruct the squid migration route.We applied this method to Ommastrephes bartramii in the North Pacific Ocean.Nine trace elements were detected in the rostrum sagittal sections(RSS)of the beak using laser ablation inductively coupled plasma mass spectrometry(LA-ICP-MS).For those elements,significant differences were found between the different ontogenetic stages for phosphorus(P),copper(Cu)and zinc(Zn).Sodium(Na),P and Zn were chosen as indicators of sea surface temperature(SST)and a regression model was estimated.The high probability of occurrence in a particular area represented the possible optimal squid location based on a Bayesian model.A reconstructed migration route in this study,combining all the locations at different ontogenetic stages,was consistent with that hypothesized in previous studies.This study demonstrates that the beak can provide useful information for identifying the migration routes of oceanic squid. 展开更多
关键词 Ommastrephes bartramii beak TRACE element ONTOGENETIC stage MIGRATION route
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Using Different Standardized Methods for Species Identification:A Case Study Using Beaks from Three Ommastrephid Species 被引量:4
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作者 HU Guanyu FANG Zhou +3 位作者 LIU Bilin CHEN Xinjun STAPLES Kevin CHEN Yong 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第2期355-362,共8页
The cephalopod beak is a vital hard structure with a stable configuration and has been widely used for the identification of cephalopod species. This study was conducted to determine the best standardization method fo... The cephalopod beak is a vital hard structure with a stable configuration and has been widely used for the identification of cephalopod species. This study was conducted to determine the best standardization method for identifying different species by measuring 12 morphological variables of the beaks of Illex argentinus, Ommastrephes bartramii, and Dosidicus gigas that were collected by Chinese jigging vessels. To remove the effects of size, these morphometric variables were standardized using three methods. The average ratios of the upper beak morphological variables and upper crest length of O. bartramii and D. gigas were found to be greater than those of I. argentinus. However, for lower beaks, only the average of LRL(lower rostrum length)/LCL(lower crest length), LRW(lower rostrum width)/LCL, and LLWL(lower lateral wall length)/LCL of O. bartramii and D. gigas were greater than those of I. argentinus. The ratios of beak morphological variables and crest length were found to be all significantly different among the three species(P < 0.001). Among the three standardization methods, the correct classification rate of stepwise discriminant analysis(SDA) was the highest using the ratios of beak morphological variables and crest length. Compared with hood length, the correct classification rate was slightly higher when using beak variables standardized by crest length using an allometric model. The correct classification rate of the lower beak was also found to be greater than that of the upper beak. This study indicates that the ratios of beak morphological variables to crest length could be used for interspecies and intraspecies identification. Meanwhile, the lower beak variables were found to be more effective than upper beak variables in classifying beaks found in the stomachs of predators. 展开更多
关键词 beak standardized METHODS DISCRIMINANT analysis Illex argentinus Ommastrephes bartramii Dosidicus GIGAS
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Morphological beak differences ofloliginid squid, Uroteuthis chinensis and Uroteuthis edulis, in the northern South China Sea 被引量:5
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作者 JIN Yue LIU Bilin +1 位作者 CHEN Xinjun Kevin STAPLES 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第2期559-571,共13页
The mitre squid(U roteuthis chinensis) and the swordtip squid( U. edulis) are Indo-Pacific cephalopod species that are abundant in the western Pacific Ocean. They are currently exploited in the East and South China Se... The mitre squid(U roteuthis chinensis) and the swordtip squid( U. edulis) are Indo-Pacific cephalopod species that are abundant in the western Pacific Ocean. They are currently exploited in the East and South China Seas and make up a significant portion of the Chinese neritic squid catch. Beaks, the feeding organs of squid, are important for individual size and biomass estimation because of their high resistance to degradation in predator stomachs and consistent dimensions. In this study, 104 U. chinensis and 143 U. edulis individuals were sampled from northern South China Sea with mantle length from 70 to 260 mm and 96 to 284 mm, respectively. The results indicated that morphological beak values were greater for U. edulis, compared to U. chinensis, for upper hood length(UHL), upper crest length(UCL), upper lateral wall length(ULWL), lower crest length(LCL), and lower lateral wall length(LLWL). According to principal component analysis, UHL/ML, UCL/ML, ULWL/ML, LCL/ML, LLWL/ML and LWL/ML could represent the characteristics of beaks for U. chinensis, while UHL/ML, UCL/ML, ULWL/ML, LHL/ML, LCL/ML and LLWL/ML could represent it for U. edulis. According to Akaike's information criterion(AIC) values, a power function was the most suitable model for U. chinensis, while a linear function was the most suitable model for U. edulis. The beak variable-mantle length ratio(beak variable/mantle length) declined with the increasing of mantle length and declined sharply at the early stage of growth in both beaks and species. The ratio changed quickly after achieving the mantle length of 140 mm for U. chinensis, while the ratio changed quickly after 170 mm for U. edulis. Beaks in both species experienced sharper changes through maturity stage I to II than other maturity stages. This study gives us basic beak morphology information for U. chinensis and U. edulis in the East and South China Seas. Geometric morphological methods combined with dietary analysis should be used in the future. 展开更多
关键词 beak morphology Uroteuthis chinensis Uroteuthis edulis northern South China Sea
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Relationship Between Beak Morphological Variables and Body Size and Mantle Length of Male and Female Argentine Shortfin Squid(Illex argentinus) 被引量:7
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作者 CHEN Xinjun LU Huajie +1 位作者 LIU Bilin FANG Zhou 《Journal of Ocean University of China》 SCIE CAS 2012年第4期539-546,共8页
Beak of cephalopod is an important hard tissue. Understanding the morphology of beak can yield critical infor- mation on the role of cephalopods in the ecosystem. The south patagonic stock of the Argentine shortfin sq... Beak of cephalopod is an important hard tissue. Understanding the morphology of beak can yield critical infor- mation on the role of cephalopods in the ecosystem. The south patagonic stock of the Argentine shortfin squid, Illex argentinus, is not only one of the most important fishing targets, but also one of the most important species in the marine eco-system of the southwest Atlantic. A total of 430 samples ofL argentinus, including 229 females 103-346mm in mantle length (ML) and 201 males 140-298mm in ML, were collected from the area off the Exclusive Economic Zone of Argentinean waters by Chinese squid jigging vessels during February to May 2007. The morphology of their beaks was evaluated. The relationships between beak morphological variables and ML differed significantly among males and females. They could be best described by loga- rithmic functions for females and linear functions for males except for upper wing length (UWL) and lower rostrum length (LRL), which followed exponential functions in their relationships with ML. The results showed the sexual dimorphism in the relationship between ML and beak morphology for the south patagonic stock ofL argentinus. However, no significant differ- ence was found between males and females in the relationships of beak morphological variables (except for UWL) versus body weight (BW), suggesting that the relationship between beak morphological variables and BW can be used for estimating the biomass consumed by their predators. 展开更多
关键词 Illex argentinus beak morphological variables mantle length body weight sexual dimorphism
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Impacts of El Nino on the somatic condition of Humboldt squid based on the beak morphology 被引量:4
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作者 HU Guanyu YU Wei +4 位作者 LI Bai HAN Dongyan CHEN Xinjun CHEN Yong LI Jianhua 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第4期1440-1448,共9页
The Humboldt squid Dosidicus gigas has a short life span, and environmental variability plays a significant role in regulating its population dynamics and distribution. An analysis of 1 096 samples of D. gigas collect... The Humboldt squid Dosidicus gigas has a short life span, and environmental variability plays a significant role in regulating its population dynamics and distribution. An analysis of 1 096 samples of D. gigas collected by the Chinese commercial fishing vessels during 2013, 2014, and 2016 off the Peruvian Exclusive Economic Zone, was conducted to evaluate the impacts of El Nino events on the somatic condition of D. gigas. This study indicates that the slopes of all beak variables in relation to mantle length (ML) for females were greater than those of males during 2013, 2014, and 2016, and slopes of the upper crest length and the lower rostrum length significantly differed between females and males in 2013 (P<0.05). Variation in the slopes for beak variables among years was studied;no significant difference was observed (ANCOVA, P>0.05). The Fulton's condition coefficients (K) of females and males in 2013 and 2014 were significantly greater than those in 2016 (P<0.01). The K values of females were greater than those of males in 2013, 2014, and 2016, and K values significantly differed between females and males in 2013. In normal years, the chlorophyll a (Chl a) concentration showed an N-shaped variability from January to December. However, in the El Nino period, it tended to weaken the upwelling coupled with warm and low Chl a concentration waters. We suggest that the poor somatic condition of D. gigas during the El Nino year was resulted from the low Chl a concentration in the waters, and the abundance of D. gigas would decrease due to the unfavourable environment and the lack of prey items in the El Nino year. 展开更多
关键词 El Nino event Dosidicus gigas somatic condition abundance beak morphology
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δ13C and δ15N in Humboldt squid beaks: understanding potential geographic population connectivity and movement 被引量:1
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作者 Bilin Liu Xinjun Chen +2 位作者 Weiguo Qian Yue Jin Jianhua Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第10期53-59,共7页
We quantified theδ^13C andδ^15N values in the lower beaks of Humboldt squid,Dosidicus gigas,collected from international waters off Costa Rica,Ecuador,Peru and Chile by Chinese squid jigging vessels during 2009,2010... We quantified theδ^13C andδ^15N values in the lower beaks of Humboldt squid,Dosidicus gigas,collected from international waters off Costa Rica,Ecuador,Peru and Chile by Chinese squid jigging vessels during 2009,2010 and 2013.There was a significant difference in the isotopic values among regions with the lowest value off Ecuador and the highest off Chile,which were interpreted as a function of trophic effects as well as baseline values.However,constant trophic level of D.gigas across its geographic range showed that spatial variation in the baseline of primary production is the main driver responsible for the observed geographic isotope variability.Inter-regional difference and intra-regional convergence of isotope values indicated squid off Costa Rica,Ecuador and Chile belong to different geographically segregated populations,which were previously proved by integrated population identifying method.In contrast,the higher variations inδ^13C andδ^15N values in a given size group suggest the squid off Peru move and forage in different places.Moreover,potential population exchange could be responsible for the overlap of the isotope values between the squid off Peru and off Chile.On the whole,the spatial difference in isotopic values of Humboldt squid beaks improves our understanding of potential geographic population connectivity and movement. 展开更多
关键词 stable ISOTOPE Dosidicus GIGAS beaks GEOGRAPHIC variability TROPHIC level the eastern Pacific Ocean
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Beak Measurements of Octopus (Octopus variabilis) in Jiaozhou Bay and Their Use in Size and Biomass Estimation 被引量:2
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作者 XUE Ying REN Yiping +4 位作者 MENG Wenrong LI Long MAO Xia HAN Dongyan MA Qiuyun 《Journal of Ocean University of China》 SCIE CAS 2013年第3期469-476,共8页
Cephalopods play key roles in global marine ecosystems as both predators and preys.Regressive estimation of original size and weight of cephalopod from beak measurements is a powerful tool of interrogating the feeding... Cephalopods play key roles in global marine ecosystems as both predators and preys.Regressive estimation of original size and weight of cephalopod from beak measurements is a powerful tool of interrogating the feeding ecology of predators at higher trophic levels.In this study,regressive relationships among beak measurements and body length and weight were determined for an octopus species(Octopus variabilis),an important endemic cephalopod species in the northwest Pacific Ocean.A total of 193 individuals(63 males and 130 females) were collected at a monthly interval from Jiaozhou Bay,China.Regressive relationships among 6 beak measurements(upper hood length,UHL;upper crest length,UCL;lower hood length,LHL;lower crest length,LCL;and upper and lower beak weights) and mantle length(ML),total length(TL) and body weight(W) were determined.Results showed that the relationships between beak size and TL and beak size and ML were linearly regressive,while those between beak size and W fitted a power function model.LHL and UCL were the most useful measurements for estimating the size and biomass of O.variabilis.The relationships among beak measurements and body length(either ML or TL) were not significantly different between two sexes;while those among several beak measurements(UHL,LHL and LBW) and body weight(W) were sexually different.Since male individuals of this species have a slightly greater body weight distribution than female individuals,the body weight was not an appropriate measurement for estimating size and biomass,especially when the sex of individuals in the stomachs of predators was unknown.These relationships provided essential information for future use in size and biomass estimation of O.variabilis,as well as the estimation of predator/prey size ratios in the diet of top predators. 展开更多
关键词 Octopus variabilis Jiaozhou Bay beak measurement body size hood length crest length
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Identification and Characterization of a Distinct Strain of Beak and Feather Disease Virus in Southeast China 被引量:1
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作者 Yanmei Ma Xiaoyong Chen +7 位作者 Keyuan Chen Xiancheng Zeng Shili Yang Wei Chang Yao Tang Xiaoli Chen Song Wang Ji-Long Chen 《Virologica Sinica》 SCIE CAS CSCD 2020年第1期43-51,共9页
Beak and feather disease virus(BFDV) is an infectious agent responsible for feather degeneration and beak deformation in birds. In March 2017, an epidemic of psittacine beak and feather disease(PBFD) struck a farm in ... Beak and feather disease virus(BFDV) is an infectious agent responsible for feather degeneration and beak deformation in birds. In March 2017, an epidemic of psittacine beak and feather disease(PBFD) struck a farm in Fuzhou in the Fujian Province of southeast China, resulting in the death of 51 parrots. In this study, the disease was diagnosed and the pathogen was identified by PCR and whole genome sequencing. A distinct BFDV strain was identified and named as the FZ strain.This BFDV strain caused severe disease symptoms and pathological changes characteristic of typical PBFD in parrots, for example, loss of feathers and deformities of the beak and claws, and severe pathological changes in multiple organs of the infected birds. Phylogenetic analysis showed that the FZ strain was more closely related to the strain circulating in New Caledonia than the strains previously reported in China. Nucleotide homology between the FZ strain and other 43 strains of BFDV ranged from 80.0% to 92.0%. Blind passage experiment showed that this strain had limited replication capability in SPF Chicken Embryos and DF-1 Cells. Furthermore, the capsid(Cap) gene of this FZ strain was cloned into the p GEX-4 T-1 expression vector to prepare the polyclonal anti-Cap antibody. Western blotting analysis using the anti-Cap antibody further confirmed that the diseased parrots were infected with BFDV. In this study, a PBFD and its pathogen was identified for the first time in Fujian Province of China, suggesting that future surveillance of BFDV should be performed. 展开更多
关键词 beak and FEATHER disease virus(BFDV) PARROT FZ STRAIN CAPSID protein(Cap) PHYLOGENETIC analysis
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Effect of Beak Trimming Stress on the Apoptosis and Its Related Protein Expression of Chicken Spleen
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作者 SUN Gui-rong LI Yan +3 位作者 KANG Xiang-tao TIAN Ya-dong ZHANG Hu LI Kui 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第4期639-645,共7页
Beak trimming was a part of routine husbandry for poultry industry,which was the most efficient and economic way to reduce the incidence of cannibalism.However,the controversy about young chicken trimming still exits ... Beak trimming was a part of routine husbandry for poultry industry,which was the most efficient and economic way to reduce the incidence of cannibalism.However,the controversy about young chicken trimming still exits and it was drawing more concern recently along with the popular of animal behavior and welfare theory.To evaluate the influence of beak trimming on young chicken spleen development and find the key regulators of the spleen development,in this study,the electron microscope technique,flow cytometry and immunohistochemical techniques were used to investigate the effects of beak trimming stress on the spleen development.The result of electronic microscope showed that significant stress response could be found in chicken spleen cells after beak trimming.Cell volume became larger,chromatin of cell nuclear agglutinated conglobation,cytoplasm formed more vacuole,and mitochondria emerged vacuolization phenomenon in splenic lymphocyte after beak trimming.From the flow cytometry,the lymphocyte of spleen in the control group and experimental group were mainly in G1 phase,and the remaining small amount was in S and M phases.Of interest,the number of the lymphocyte which are in G1 phase within immune organ in the experimental group were more than that in the control group,but the number of cells in S and M phases were less than that in the control group.And beak trimming decreased the lymphocytes proliferation index of spleen.Inmmuohistochemical result showed that the beak trimming stress did not affect the expression sites of two apoptosis-related genes,Bcl-2 and Bax,in the spleen.But the expression level of Bcl-2 decreased while Bax increased in chicken immune organs after beak trimming.Furthermore,the beak trimming increased spleen cell apoptosis with a time-dependant style.Our findings may make a contribution to the active precaution of stress response. 展开更多
关键词 CHICKEN beak trimming stress reaction SPLEEN APOPTOSIS
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The structures of eye and surrounding tissues of Longman's beaked whale,Indopacetus pacificus
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作者 祝茜 山田格 李响 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第2期219-221,共3页
Observations were made on one eye from a Longman’s beaked whale Indopacetus pacificus, which was probably one of the least known extant cetaceans. The whale died shortly after swimming aground on the coast in the Nis... Observations were made on one eye from a Longman’s beaked whale Indopacetus pacificus, which was probably one of the least known extant cetaceans. The whale died shortly after swimming aground on the coast in the Nishikata Beach, Sendai-shi, Kagoshima-ken Prefecture, Japan, on July 26, 2002. It was a mature female with body length 6.45 m. This paper documented the basic structural characteristics of her visual organ of the whale in order to better understand this animal. 展开更多
关键词 Longman's beaked whale lndopacetuspacificus eye structure ANATOMY MORPHOLOGY
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Axial compression physical testing of traditional and bird beak SHS T-joints
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作者 陈誉 王江 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第6期2328-2338,共11页
The static tests of nine traditional and bird beak square hollow structure(SHS) T-joints with different β values and connection types under axial compression at brace end were carried out. Experimental test schemes, ... The static tests of nine traditional and bird beak square hollow structure(SHS) T-joints with different β values and connection types under axial compression at brace end were carried out. Experimental test schemes, failure modes of specimens, jack load-vertical displacement curves, jack load-deformation of chord and strain intensity distribution curves of joints were presented. The effects of β and connection types on axial compression property of joints were studied. The results show that the ultimate axial compression capacity of common bird beak SHS T-joints and diamond bird beak SHS T-joints is larger than that of traditional SHS T-joint specimens with big values of β. The ultimate axial compression capacity of diamond bird beak SHS T-joints is larger than that of common bird beak SHS T-joints. As β increases, the increase of the ultimate axial compression capacity of diamond bird beak SHS T-joints over that of common bird beak joints grows. The ultimate axial compression capacity and the initial axial stiffness of all kinds of joints increase as β increases, and the initial axial stiffness of the diamond bird beak SHS T-joints is the largest. The ductilities of common bird beak and diamond bird beak SHS T-joints increase as β increases, but the ductility of the traditional SHS T-joints decreases as β increases. 展开更多
关键词 bird beak SHS T-joints axial compression property physical testing ultimate axial compression capacity initial axial compression stiffness strain intensity distribution DUCTILITY
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Prevalence of Psittacine Beak and Feather Disease Virus and Avian Polyomavirus in Captivity Psittacines from Costa Rica
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作者 Gaby Dolz Jessica Sheleby-Elías +3 位作者 Juan J.Romero-Zuniga Bernardo Vargas-Leiton Gustavo Gutiérrez-Espeleta Kenneth Madriz-Ordenana 《Open Journal of Veterinary Medicine》 2013年第4期240-245,共6页
Psittacine beak and feather disease virus (PBFDV) and avian polyomavirus (APV) are the most common viral diseases in psittacine birds, both affecting feathers and physical appearance of birds. Between 2005 and 2009, a... Psittacine beak and feather disease virus (PBFDV) and avian polyomavirus (APV) are the most common viral diseases in psittacine birds, both affecting feathers and physical appearance of birds. Between 2005 and 2009, a total of 269 samples were collected from birds presented at veterinary clinics, shelters and rescue centers of wildlife in Costa Rica. They belonged to 19 species of psittacine birds. The most representative species in the sample were Ara macao (157), Ara ambigua (37), Amazona autumnalis (24), Amazon ochrocephala (21) and Ara ararauna (8). A prevalence of 19.7% (53/269) for PBFDV and 4.8% (13/269) for APV was determined using Polymerase Chain Reaction (PCR). In 3.3% (9/269) of the birds mixed infections were detected. Statistical analysis determined that psittacines living in shelters and rescue centers had a greater risk to be positive to PBFDV and APV than birds that were presented at veterinary clinics, while only for PBFDV it was determined, that it is more likely to detect it in feathers than in blood. Finally, birds infected with PBFDV had 6.24 times more probability to become infected with APV, than non-infected birds. This is the first report of prevalence of PBFDV and APV in captive psittacines from Costa Rica. 展开更多
关键词 Psittacine beak and Feather Disease Virus Avian Polyomavirus Psittacine Birds Costa Rica
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基于Sf9细胞培养表达鸭短喙侏儒综合征病毒VP2蛋白的工艺优化
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作者 甘辉群 王永娟 +3 位作者 吴双 傅宏庆 谭菊 刘明生 《畜牧与兽医》 北大核心 2025年第9期87-92,共6页
旨在获得高表达的鸭短喙侏儒综合征病毒VP2抗原蛋白。本试验通过对接毒与表达工艺中pH值、Sf9细胞密度、接毒量、收获时间、搅拌转速和溶氧值等参数进行优化,考察VP2重组杆状病毒的增殖情况,收获病毒液,测定病毒含量变化;同时,对培养物... 旨在获得高表达的鸭短喙侏儒综合征病毒VP2抗原蛋白。本试验通过对接毒与表达工艺中pH值、Sf9细胞密度、接毒量、收获时间、搅拌转速和溶氧值等参数进行优化,考察VP2重组杆状病毒的增殖情况,收获病毒液,测定病毒含量变化;同时,对培养物进行VP2蛋白SDS-PAGE和Western blot分析,并采用SDS-PAGE灰度扫描测定蛋白含量。结果:在pH值维持6.8~7.2,接毒密度为1.0×10^(6)~2.0×10^(6)个/mL,感染复数(MOI)值为0.01~0.1,收获时间为接种后5~7 d,转速100~140 r/min,溶氧度控制在40%~80%时,重组杆状病毒生长较好,含量较高,达10^(7.7)~10^(8.5) TCID_(50)/mL;均出现约65 kDa目的条带,蛋白表达量基本一致,达57μg/mL以上。根据优化的工艺参数在5 L反应器进行5批抗原生产验证,VP2蛋白表达量达58~63μg/mL,蛋白生产稳定,表达量高。 展开更多
关键词 鸭短喙侏儒综合征 重组杆状病毒 SF9细胞 接毒工艺 表达生产工艺
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鸭短喙矮小综合征病毒抗体间接ELISA检测方法的建立与初步应用
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作者 朱小丽 王劭 +5 位作者 董慧 程晓霞 江丹丹 肖世峰 陈少莺 陈仕龙 《福建农业学报》 北大核心 2025年第7期649-655,共7页
【目的】建立一种快速检测鸭短喙矮小综合征病毒(Short beak and dwarfism syndrome virus,SBDSV)抗体的血清学方法。【方法】以蔗糖密度梯度离心纯化的SBDSV流行株M15,以此灭活全病毒作为固相包被抗原,通过系统性优化反应参数,构建一... 【目的】建立一种快速检测鸭短喙矮小综合征病毒(Short beak and dwarfism syndrome virus,SBDSV)抗体的血清学方法。【方法】以蔗糖密度梯度离心纯化的SBDSV流行株M15,以此灭活全病毒作为固相包被抗原,通过系统性优化反应参数,构建一种高特异性的间接ELISA检测方法,用于鸭短喙矮小综合征病毒(SBDSV)血清抗体的定性分析。【结果】建立的间接ELISA检测方法的最佳反应条件为:抗原包被浓度0.1 mg·mL^(−1),37℃孵育2 h后再4℃过夜包被;1%BSA 37℃封闭2 h;血清样本1∶200稀释;阴阳性临界值为0.3214。该检测方法特异性好,与其他常见水禽病毒阳性血清均无交叉反应;敏感性高,阳性高免血清(LPAI效价2^(8))1∶204800倍稀释时检测结果仍为阳性;批内、批间重复性好,变异系数均小于6%;利用所建立的ELISA方法对70份SBDSV疑似感染病鸭的血清样品进行检测,检测结果与LPAI检测结果符合率为90%。对福建省648份临床送检1日龄雏鸭血清样品进行检测,抗体阳性率约为48.30%,显示福建省养鸭场存在不同程度的SBDSV感染。【结论】本研究建立的SBDSV血清抗体间接ELISA检测方法,该方法特异性高,适合大规模血清学检测,可为监测SBDSV在我国的流行情况以及雏鸭母源抗体水平评价提供技术支撑。 展开更多
关键词 鸭短喙矮小综合征 间接ELISA 抗体检测
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First live sighting of Deraniyagala’s beaked whale(Mesoplodon hotaula)or ginkgo-toothed beaked whale(Mesoplodon ginkgodens)in the western Pacific(South China Sea)with preliminary data on coloration,natural markings,and surfacing patterns 被引量:2
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作者 Massimiliano ROSSO Mingli LIN +7 位作者 Francesco CARUSO Mingming LIU Lijun DONG Anna BORRONI Wenzhi LIN Xiaoming TANG Alessandro BOCCONCELLI Songhai LI 《Integrative Zoology》 SCIE CSCD 2021年第4期451-461,共11页
Beaked whales represent around 25%of known extant cetacean species,yet they are the least known of all marine mammals.Identification of many Mesoplodon species has relied on examination of a few stranded individuals.P... Beaked whales represent around 25%of known extant cetacean species,yet they are the least known of all marine mammals.Identification of many Mesoplodon species has relied on examination of a few stranded individuals.Particularly,the ginkgo-toothed beaked whale(Mesoplodon ginkgodens)and Deraniyagala’s beaked whale(Mesoplodon hotaula)are among the least-known of beaked whale species,without confirmed sightings of living individuals to date.We present a sighting of 3 free-ranging individuals of M.ginkgodens/hotaula whale from a dedicated marine mammal vessel survey carried out in the South China Sea in April and May 2019.Photographic data(301 photographs)from the sighting were compared to photos of fresh stranded ginkgo-toothed beaked whale and Deraniyagala’s beaked whale from both historical and unpublished records.We found that free-ranging M.ginkgodens and M.hotaula individuals can be easily distinguished from other Mesoplodon species due to differences in melon and gape shapes and coloration patterns.However,accurate at-sea differentiation of M.ginkgodens and M.hotaula may not be possible due to high similarity in both coloration and scarring patterns.In addition to our photo-identification data,we collected what we believe to be the first preliminary descriptions of surfacing behavior and diving patterns of one of these species.Finally,the presence of scars possibly caused by fishing gear or marine litter raises concerns about anthropogenic impacts and conservation of these poorly known species. 展开更多
关键词 Deraniyagala’s beaked whale ginkgo-toothed beaked whale marine litter Mesoplodon South China Sea
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天津地区首例虎皮鹦鹉喙羽症合并幼雏病的诊断
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作者 徐国栋 杨丹 +4 位作者 张颖 王健春 蒙晓雷 赵静 周永燚 《中国兽医卫生》 2025年第4期81-86,共6页
为诊断天津地区某养殖场虎皮鹦鹉幼雏出现的以羽毛生长发育障碍、高病死率为主要临床特点的疾病,笔者从鹦鹉发病概况、典型临床症状和病理剖检变化、细菌学和病毒学检测结果等方面进行了综合诊断,最终确诊该群鹦鹉幼雏合并发生鹦鹉喙羽... 为诊断天津地区某养殖场虎皮鹦鹉幼雏出现的以羽毛生长发育障碍、高病死率为主要临床特点的疾病,笔者从鹦鹉发病概况、典型临床症状和病理剖检变化、细菌学和病毒学检测结果等方面进行了综合诊断,最终确诊该群鹦鹉幼雏合并发生鹦鹉喙羽症(Psittacine Beak and Feather Disease,PBFD)和虎皮鹦鹉幼雏病(Budgerigar Fledgling Disease,BFD)。上述两种疫病是天津地区首次公开报道的病例,提醒养殖者关注这两种疫病的防治。 展开更多
关键词 天津 鹦鹉 喙羽症 幼雏病 诊断
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人工养殖曼氏无针乌贼的角质颚形态特征与生长特性研究
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作者 徐晓萱 隋宥珍 +7 位作者 张涛 刘连为 徐开达 朱文斌 徐汉祥 周永东 LIU Shuhan ZHU Kai 《海洋湖沼通报(中英文)》 北大核心 2025年第3期98-105,共8页
作为浙江沿岸重要经济头足类之一,曼氏无针乌贼(Sepiella maindroni)在生态系统中扮演重要角色,其硬组织角质颚可作为渔业生态学研究的重要材料。本文基于人工养殖条件下曼氏无针乌贼494对角质颚,开展其形态特征及生长特性研究。由主成... 作为浙江沿岸重要经济头足类之一,曼氏无针乌贼(Sepiella maindroni)在生态系统中扮演重要角色,其硬组织角质颚可作为渔业生态学研究的重要材料。本文基于人工养殖条件下曼氏无针乌贼494对角质颚,开展其形态特征及生长特性研究。由主成分分析结果可知,上头盖长(UHL)、上脊突长(UCL)、下脊突长(LCL)、下侧壁长(LLWL)可作为曼氏无针乌贼角质颚外部形态特征参数。协方差分析结果显示,角质颚外部形态参数UHL、UCL、LCL与LLWL在雌雄性别间存在着显著差异(P<0.01)。选择的雌性个体角质颚上头盖长、雌雄个体角质颚上脊突长、雌雄个体角质颚下侧壁长参数与胴长呈幂函数关系,雄性个体角质颚上头盖长、雄性个体角质颚下脊突长参数与胴长呈对数函数关系,雌性个体角质颚下脊突长参数与胴长呈指数函数关系。角质颚生长情况表明,雌雄个体角质颚形态参数绝对增长率与相对增长率随着日龄的增加总体上呈下降趋势,最小值均出现在86~95日龄期间。角质颚外形特征参数及其与胴长函数关系的确定可用于曼氏无针乌贼种群判别,其生长特性为曼氏无针乌贼规模化养殖摄食生态学研究提供科学依据。 展开更多
关键词 曼氏无针乌贼 人工养殖 角质颚 外部形态参数 生长特性
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