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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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Growth Performance of Crocodile Fed with Chicken Intestine and Trash Fish at Smallholder Farm in Siem Reap Province,Cambodia
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作者 Sourloing Hor Kanan Dim +3 位作者 Sungchang Kang Kroesna Kang Kouch Theng Manay Ith 《Journal of Environmental Science and Engineering(B)》 CAS 2024年第2期86-91,共6页
The experiment was conducted at the smallholder crocodile farm at Pouk district,Siem reap province,and lasted 12 months,commenced from January 1st to December 31st,2023.The CRBD(Completely Randomized Block Design),was... The experiment was conducted at the smallholder crocodile farm at Pouk district,Siem reap province,and lasted 12 months,commenced from January 1st to December 31st,2023.The CRBD(Completely Randomized Block Design),was used in 3 treatments,such as T1(fed chicken intestine only),T2(fed chicken intestine+trash fish)and T3(fed trash fish only),with 4 replications in each treatment.The block was set by gender of crocodile,male and female.The 36 of local breed crocodiles 4 months old were allocated into each replication randomly.The result found that the length of crocodile gradually increased in the first semester,then it greatly increased from or for second semester for all treatments.In addition,the final body length of crocodile was significant different among treatments(p<0.001),the treatment of T2(fed chicken intestine+trash fish)had the longest one.Body length was also affected by gender,and male crocodile had longer body length(p<0.001).However,there were no significant differences for the interaction between types of feed with gender(p>0.05)(Table 1).The body weight of crocodile had gradually increased in the first semester,then it greatly increased from or for second semester for all treatments,while the final body weight of crocodile was also significant different among treatments(p<0.001)and the gender of crocodile(p<0.001).The average ADG(Daily Weight Gain)was significant different among treatments(p<0.001).Treatment of T2(fed chicken intestine+trash fish)had highest ADG,11.05 g,followed by T3(fed trash fish only),while the T1 had the lowest one.The gender of crocodile affected the ADG of crocodile,and male crocodile had higher ADG than female crocodile(p<0.001).However,there were no significant differences for the interaction between type of feed with gender(p>0.05).Feed intake was calculated based on amount of feed offer and measured in fresh basis.The amount of intake feed in all treatments was the same.FCR(Feed Conversion Ratio)was significant different among treatments(p<0.001)and also gender of crocodile(p<0.001).However,there were no significant differences for the interaction between types of feed with gender(p>0.05).In conclusion,the uses of trash fish and chicken intestine are an alternative feed source for crocodile to result in higher growth performance of crocodile. 展开更多
关键词 Local breed body length body weight ADG FCR
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Dynamic genetic analysis for body weight and main length ratio in turbot Scophthalmus maximus
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作者 Xin’an Wang Aijun Ma 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第2期22-27,共6页
The objective of this study was to estimate genetic parameters of body width(BW)to body length(BL)ratio(BW/BL)and of body weight traits(BWT)in turbot,and to elucidate the genetic mechanism of the two traits during ont... The objective of this study was to estimate genetic parameters of body width(BW)to body length(BL)ratio(BW/BL)and of body weight traits(BWT)in turbot,and to elucidate the genetic mechanism of the two traits during ontogeny by dynamic genetic analysis.From 3 to 27 months,BW,BL and BWT of each communally stocked fish were measured every 3 months.The BW/BL ratio was measured at different sampling ages.A twotrait animal model was used for genetic evaluation of traits.The results showed that the heritability values of BW/BL ratio ranged from 0.2168 to 0.3148,corresponding to moderate heritability.The BWT heritability values ranged from 0.2702 to 0.3479 corresponding to moderate heritability.The heritability of BW/BL ratio was lower than that of BWT,except at 3 months of age.Genetic correlation between BW/BL ratio and BWT decreased throughout the measurement period.Genetic correlations were higher than the phenotypic correlations.The current results for estimating genetic parameters demonstrate that the BW/BL ratio could be used as a phenotypic marker of fast-growing turbot,and the BW/BL ratio and BWT could be improved simultaneously through selective breeding. 展开更多
关键词 TURBOT dynamic genetic analysis body weight main length ratio heritability genetic correlation
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Regulation of water quality and growth characteristics of indoor raceway culture of Litopenaeus vannamei 被引量:4
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作者 臧维玲 杨明 +3 位作者 戴习林 侯文杰 刘永士 丁福江 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第4期740-747,共8页
Two modes of regulating the water quality of experimental ponds in indoor raceway culture of Litopenaeus vannamei were evaluated using simple water treatment facilities. A self-made water purifying net, aeration stone... Two modes of regulating the water quality of experimental ponds in indoor raceway culture of Litopenaeus vannamei were evaluated using simple water treatment facilities. A self-made water purifying net, aeration stone, composite microbe preparation, and Ceratophyllum demersum were placed in the experimental ponds and the culture water was circulated along the raceway inside the pond using a paddle wheel aerator. In addition, the water quality in the experimental pond was improved by draining effluent from the pipeline at the bottom of ponds 7 and 8 (mode I) and exchanging the circulating water in pond 10 (mode Ⅱ) with the reservoir water in pond 9 using a pump and pipeline. The water quality in the experimental ponds was similar in response to regulation using mode Ⅰ or mode Ⅱ. Water quality parameters in the experimental ponds were controlled within a suitable range by simple facilities during culture period without using any chemical treatments. The rich content of dissolved oxygen was maintained by the circular flow and continuous aeration of the pond water. The respective average values of the main water parameters in experimental ponds 7 and 10 in response to regulation of the water quality using modes Ⅰ and Ⅱwere as follows: pH 8.17 and 7.99; DO 5.16 mg/L and 5.97 mg/L; CODMn18.45 and 12.61 mg/L; TAN (NH3-N) 0.854 mg/L (0.087 mg/L) and 0.427 mg/L (0.012 mg/L); NO2-N 0.489 mg/L and 0.337 mg/L. Moreover, the average body length and body weight of harvested shrimp of pond 7 and pond l0 were 7.56 cm and 8.99 cm, 5.10 g and 8.33 g, respectively. Furthermore, the survival rate, average biomass yield and average condition factor of the shrimp harvested were 70% and 60%, 2.54 kg/m2 and 2.14 kg/m2, and 0.675 g/cm and 0.927 g/cm, respectively. Linear equations describing the relationship between body length and culture time and cubic or power functions describing the relationship between body weight and body length were obtained based on evaluation of the growth data of shrimps throughout the culture period. 展开更多
关键词 Litopenaeus vannamei RACEWAY water purifying net body length body weight regressiveequation
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Ameliorating Effects of Thyroxine and Atropine in Phosphamidon Intoxicated Chick Embryos
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作者 CHATTALI GHOSH AND J.N.MEDDA (Department of Zoology, Burdwan University, Burdwan 713104,West Bengal, INDIA)J.N.MEDDA (To whom all corespondences should be addressed.E-mail:zoojnm@burdwan.ernet.in.) 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1999年第1期34-42,共9页
The effects of thyroxine and atropine in ameliorating phosphamidon intoxication in chick embryos was studied. Treatment of phosphamidon significantly enhanced the moriality and abnormalityrates, decreased the average ... The effects of thyroxine and atropine in ameliorating phosphamidon intoxication in chick embryos was studied. Treatment of phosphamidon significantly enhanced the moriality and abnormalityrates, decreased the average body weights, and cholinesterase activity in chick embryos. When thyroxine was administered to the phosphamidon intoxicated embryos, the above parameters changedsignificantly, indicating an ameliorating effect of thyroxine against phosphamidon intoxication in chick embryos. The combined thyroxine and atropine therapy did not further improve the ameliorating effect. Since in many respects chick embryo development parallels that of mammalian embryos,a short-term use of thyroxine as a protective agent against organophosphate toxicity might be useful 展开更多
关键词 ANIMALS ATROPINE body weight Central Nervous System Chick Embryo Cholinesterase Inhibitors CHOLINESTERASES Dose-Response relationship Drug INSECTICIDES Kidney Liver Phosphamidon THYROXINE
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贵州北部云南光唇鱼野外和驯养种群的生长模式研究
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作者 肖贵榜 张浩然 +6 位作者 廖丽 陆武军 毛茜 陈兴科 周林 鲍娟 王礼节 《贵州农业科学》 CAS 2024年第5期68-75,共8页
【目的】探明贵州北部云南光唇鱼(Acrossocheilusyunnanensis)自然栖息环境和驯养条件下体长与体重的关系,分析其群体生长规律,为当地云南光唇鱼资源的保护和开发提供参考。【方法】测定野外种群和驯养种群个体的体长、体重,利用单因素... 【目的】探明贵州北部云南光唇鱼(Acrossocheilusyunnanensis)自然栖息环境和驯养条件下体长与体重的关系,分析其群体生长规律,为当地云南光唇鱼资源的保护和开发提供参考。【方法】测定野外种群和驯养种群个体的体长、体重,利用单因素方差分析、t检验、幂函数回归等方法分析有关指标。【结果】云南光唇鱼野外种群体长为80~171 mm,平均体长为(134.55±20.34)mm;驯养种群体长为150~245 mm,平均体长为(167.51±15.18)mm;平均体长驯养种群显著大于野生种群。云南光唇鱼野生种群体重为21~112 g,平均体重为(69.92±18.99)g;驯养种群体重为52.9~143.0 g,平均体重为(78.03±18.42)g;驯养种群平均体重显著大于野生种群。云南光唇鱼野外种群体长和体重均呈左偏分布,驯养种群均呈右偏分布。从变异系数看,云南光唇鱼野外种群体长和体重整齐度均低于驯养种群。云南光唇鱼体长-体重关系式野生种群为W=0.0011L^(1.9896)(n=100,R^(2)=0.9847),驯养种群为W=0.0002L^(2.2119)(n=100,R^(2)=0.7758)。野生种群与驯养种群体长与体重参数a值和b值分别为0.000005~0.009397和1.5176~2.8341。野生种群与驯养种群的参数a值呈由高到低的变化趋势,参数b值呈与a值相反的变化趋势。单因素方差分析表明,云南光唇鱼野外种群与驯养种群各阶段体长与体重关系参数a值、b值差异不显著。t检验表明,野外种群b值与3差异极显著,驯养种群b值与3差异不显著。【结论】贵州北部云南光唇鱼野外种群生长为负异速生长,人工驯养条件下为等速生长。贵州北部云南光唇鱼野生环境优于驯养试验环境,天然栖息环境和驯养环境的综合环境条件均较差。 展开更多
关键词 云南光唇鱼 野生种群 驯养种群 生长模式 体长-体重相关性(LWR) 芙蓉江
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黑棘鲷5个不同群体的生长性能比较
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作者 倪可雯 贾超峰 +3 位作者 徐大凤 孟乾 周堂建 陈淑吟 《水产科技情报》 2024年第5期273-282,共10页
为探究黑棘鲷不同群体间生长性能的差异,对其3个选育系(XY_(1)、XY_(2)、XY_(3))和杂交鲷(HF_(2),黑棘鲷Acanthopagrus schlegelii♀×真鲷Pagrus major♂杂交子二代)以及野生群体子一代(YS)的生长特性进行了初步研究和比较。从5个... 为探究黑棘鲷不同群体间生长性能的差异,对其3个选育系(XY_(1)、XY_(2)、XY_(3))和杂交鲷(HF_(2),黑棘鲷Acanthopagrus schlegelii♀×真鲷Pagrus major♂杂交子二代)以及野生群体子一代(YS)的生长特性进行了初步研究和比较。从5个群体中分别选取1000尾幼鱼(3月龄,体质量2.28~5.07 g,体长4.26~5.55 cm)进行养殖试验,并在0、30、60、90 d时测量各群体的生长数据。试验结果显示:养殖30 d时,黑棘鲷5个群体间的肥满度无显著性差异(P>0.05),HF_(2)群体的体质量、体长绝对增长率显著低于XY_(1)和XY_(2),YS群体的体质量、体长特定增长率及体长相对增长率均显著低于其他4个群体,其体质量相对增长率仅显著低于XY_(1)和XY_(2)群体(P<0.05);养殖60 d时,XY_(3)群体的体质量绝对增长率显著高于XY_(1)和YS群体,YS群体的体质量、体长特定增长率及相对增长率均显著低于其他4个群体(P<0.05);养殖90 d时,5个群体间的肥满度无显著性差异(P>0.05),HF_(2)群体的体质量、体长绝对增长率与体质量特定增长率显著高于XY_(1)、XY_(2)和YS群体,其体长特定增长率显著高于除XY_(2)外的另3个群体(P<0.05);体长-体质量幂函数关系式显示,5个群体试验鱼均处于异速生长状态(b<3)。研究结果表明:黑棘鲷5个群体的生长性能存在差异,其生长速度排序为HF_(2)>XY_(2)>XY_(1)>XY_(3)>YS,凸显出了选育系的遗传稳定性和HF_(2)的杂交优势。 展开更多
关键词 黑棘鲷 生长发育 体长 体质量
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黑龙江流域黑龙江茴鱼个体繁殖力研究
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作者 韩豪祥 金洪宇 +2 位作者 廉杰 薄永芳 马波 《湖南农业大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第3期89-93,共5页
在黑龙江流域呼玛河、额木尔河采集黑龙江茴鱼332尾,经鉴定,雄鱼180尾,雌鱼133尾,雌雄不辨19尾。对63尾性腺发育达到Ⅳ期的雌鱼测量体长、体质量、净体质量、卵巢质量、年龄,计算性腺成熟系数、肥满度等;取其卵巢前、中、后约0.25 g性... 在黑龙江流域呼玛河、额木尔河采集黑龙江茴鱼332尾,经鉴定,雄鱼180尾,雌鱼133尾,雌雄不辨19尾。对63尾性腺发育达到Ⅳ期的雌鱼测量体长、体质量、净体质量、卵巢质量、年龄,计算性腺成熟系数、肥满度等;取其卵巢前、中、后约0.25 g性腺组织称重、计数,计算个体繁殖力;运用SPSS 16.0将雌鱼个体绝对繁殖力(F)、体长相对繁殖力(FL)、体质量相对繁殖力(Fm)与生物学指标进行多元线性回归分析,获得全回归方程,从中筛选出P值小于0.05的指标,再次进行多元线性回归分析,最终建立标准化回归方程;将个体繁殖力与7项生物学指标分别进行拟合,从中筛选出拟合度最高的方程。结果表明:黑龙江茴鱼繁殖群体由2~4龄个体组成,个体绝对繁殖力为(2152.63±905.96)粒;体长相对繁殖力为(11.11±3.01)粒/mm;体质量相对繁殖力为(22.99±1.62)粒/g;多元回归分析表明,个体绝对繁殖力与卵巢质量呈正相关,且偏相关系数最高;从最佳拟合方程中可以看出,个体绝对繁殖力与卵巢质量(m0)的拟合度最高(R^(2)=0.9843),关系式为F=0.8126m0^(2)+234.09m0+520.14,可以用个体绝对繁殖力和卵巢质量的最佳拟合方程估算野生黑龙江茴鱼种群的繁殖力。 展开更多
关键词 黑龙江茴鱼 个体绝对繁殖力 体长相对繁殖力 体质量相对繁殖力
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东北兔(Lepus mandshuricun Radde)野外种群三种年龄鉴定指标的比较
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作者 周晓梅 周天 马建章 《东北师大学报(自然科学版)》 CAS CSCD 北大核心 2003年第4期57-61,共5页
 东北兔各年龄组间体重、体长均有极显著差异,表明随年龄增长东北兔的体重、体长也相应增长.对不同年龄组的东北兔晶体质量与体重、体长做相关分析,结果表明,Ⅰ,Ⅱ,Ⅲ龄组的东北兔晶体质量与体重、体长之间相关非常显著,可以认为它们...  东北兔各年龄组间体重、体长均有极显著差异,表明随年龄增长东北兔的体重、体长也相应增长.对不同年龄组的东北兔晶体质量与体重、体长做相关分析,结果表明,Ⅰ,Ⅱ,Ⅲ龄组的东北兔晶体质量与体重、体长之间相关非常显著,可以认为它们是同步增长的;Ⅳ龄组的东北兔晶体质量与体重、体长之间的相关不显著,可以认为它们不是同步增长的. 展开更多
关键词 东北兔 种群组成 晶体质量 体重 体长
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Population dynamics of Japanese threadfin bream Nemipterus japonicus from Pakistani waters 被引量:1
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作者 KALHORO Muhsan Ali LIU Qun +2 位作者 MEMON Khadim Hussain CHANG Mohammad Saleem ZHANG Kui 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第10期49-57,共9页
Japanese threadfin bream Nemipterus japonicus(Bloch, 1791) is among the most abundant and commercially important species in Pakistan. From the coast of Pakistan, four demersal trawl surveys in October–November 2009... Japanese threadfin bream Nemipterus japonicus(Bloch, 1791) is among the most abundant and commercially important species in Pakistan. From the coast of Pakistan, four demersal trawl surveys in October–November 2009 and May–June, August, October and November in 2010 were carried out. The purpose of this study is to estimate the population dynamics and status of the stock of the N. japonicus from Pakistani waters based on the research trawl surveys from the research area. The data consist of n=784 length-weight pairs and n=7 530 length frequency with the maximum length and weight of 29 cm and 358 g respectively. The length frequency data were analyzed using ELEFAN method in FiSAT computer package. The parameters of length and weight relationship were b=2.778, a=0.032 and R2=0.973. The estimated von Bertalanffy growth function parameters were L∞=30.45 cm, K=0.270 year-1. Based on length-converted catch curve analysis the total mortality(Z) during this study was estimated at 0.960 year-1. The natural mortality coefficient(M) was 0.74 year-1 using Pauly's equation(the annual average sea surface temperature was 27°C), therefore, the fishing mortality coefficients(F) were 0.22 year-1. The yield per recruit analysis indicated that when tc was 2, Fmax was estimated at 1.2 and F0.1 at 1.1. When tc was 1, Fmax was estimated at 0.95 and F0.1 at 0.8. Because current age at first capture is about 1 year and Fcurrent was 0.22, Fcurrent is smaller than F0.1 and Fmax, which indicated that the fishery is about in a safe condition. When using Gulland(1971) biological reference point, Fopt was equals to M(0.74). The current fishing mortality rate of 0.22 was smaller than the target biological reference point. 展开更多
关键词 Pakistan Nemipterus japonicus length-weight relationship growth MORTALITY
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Intersexual plasticity in aspects of the biology of the mudskipper Periophthalmus barbarus (Gobhdae) in the mangrove swamps of IMO Estuary, Nigeria
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作者 Mfon T. Udo (Department of Fisheries and Aquaculture University of Uyo, PMB 1017, Uyo Akwa Ibom State, Nigeria.) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2002年第1期95-101,共7页
Between April 1992 and March 1993, intersexual plasticity in aspects of the biology of the mudskipper, Periophthalmus barbarus was studied. Sex was differentiated on the basis of the genital papillae, it was broa... Between April 1992 and March 1993, intersexual plasticity in aspects of the biology of the mudskipper, Periophthalmus barbarus was studied. Sex was differentiated on the basis of the genital papillae, it was broader in females than males. Sexually active females were slightly heavier than similarly sized males. Sex ratio was strongly female biased. Length weight relationship of the sexes was isometric. There was no significant difference in the feeding intensity of both sexes; uniformity was also apparent in diet breadth. There was no named sex based difference in hepatosometic index but condition index was higher in males than females. The uniformity in intersexual plasticity of P.barbarus is consequent upon homogeneity of the mangrove ecosystem, which can only be altered anthropogenically. 展开更多
关键词 intersexual plasticity Periophthalmus barbarus mangrove swamp length weight relationship feeding intensity
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大渡河理县高原鳅体长体重关系、遗传多样性和分化水平 被引量:1
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作者 赖见生 陈叶雨 +7 位作者 颜涛 林珏 黄颖颖 赵凤麒 陈永胜 周启红 刘晓欢 何斌 《西南农业学报》 CSCD 北大核心 2023年第11期2544-2552,共9页
【目的】为研究理县高原鳅不同地理种群的遗传多样性和群体结构,进一步利用理县高原鳅的遗传种质资源并对其野生群体进行保护,获取长江流域理县高原鳅种群结构信息。【方法】对大渡河理县高原鳅体重和体长组成、体长-体重关系进行研究,... 【目的】为研究理县高原鳅不同地理种群的遗传多样性和群体结构,进一步利用理县高原鳅的遗传种质资源并对其野生群体进行保护,获取长江流域理县高原鳅种群结构信息。【方法】对大渡河理县高原鳅体重和体长组成、体长-体重关系进行研究,并利用线粒体DNA控制区D⁃loop序列,对理县高原鳅4个地理种群共117个个体进行遗传结构变异分析。【结果】理县高原鳅体重和体长的回归方程为y=0.0123x2.9734,b值为2.9734,接近3,表明目前理县高原鳅生长状态良好。利用线粒体分子标记,在4个种群个体中共扩增获得878 bp的D⁃loop同源序列,包含28个单倍型和32个多态性位点,4个种群之间无共享单倍型。4个理县高原鳅群体的单倍型多样度在0.637~0.921,核苷酸多样性在0.00091~0.00570。通过分析遗传距离发现,金川县和丹巴县、泸定县和石棉县之间的理县高原鳅群体未发生遗传分化,而泸定县与金川县或丹巴县、石棉县与金川县或丹巴县之间的理县高原鳅群体均存在显著的遗传分化。通过构建NJ进化树发现,117个理县高原鳅个体在进化树上形成2个独立分支,与各地理种群的遗传分化结果一致。【结论】建议将大渡河金川县和丹巴县理县高原鳅种群作为一个整体进行管理和保护,石棉县和泸定县也作为一个整体进行管理和保护,而金川县和丹巴县、石棉县和泸定县的种群建议分开管理和保护。 展开更多
关键词 理县高原鳅 体长体重关系 遗传多样性 D⁃loop
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尿素清除率K 作为影响血液透析患者透析充分性重要指标的临床研究
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作者 张洪利 朱强 +2 位作者 廖永平 田冲 高宁 《中国血液净化》 CSCD 2023年第10期744-748,共5页
目的通过联机清除率监测(online clearance monitoring,OCM)实时动态监测,探讨透析过程中尿素清除率(urea clearance,K)的变化规律、影响因素及与透析充分性之间的量化关系。方法应用OCM观察152例血液透析患者透析中不同时段的K值,采用... 目的通过联机清除率监测(online clearance monitoring,OCM)实时动态监测,探讨透析过程中尿素清除率(urea clearance,K)的变化规律、影响因素及与透析充分性之间的量化关系。方法应用OCM观察152例血液透析患者透析中不同时段的K值,采用重复测量方差分析探究透析过程中K变化规律;采用多元线性回归分析平均K值的影响因素;采用Pearson进行相关性分析。结果K随时间变化呈线性下降(F=447.552,P<0.001)。血流量(β=0.706,95%CI:0.403~0.526,P<0.001)、超滤系数(β=0.183,95%CI:0.074~0.223,P<0.001)与K呈正相关,红细胞比容(HCT)(β=-0.242,95%CI:-0.877~-0.405,P<0.001)、年龄(β=-0.106,95%CI:-0.209~-0.011,P=0.030)与K呈负相关。K与3倍干体质量的差值和Kt/V之间存在显著相关性(r=0.808,P<0.001)。结论透析过程中K呈线性缓慢下降。提高K的手段是增加血流量、使用高通量透析器,控制HCT在33%~36%。若透析充分性达标,K应大于干体质量的3倍。 展开更多
关键词 尿素清除率 透析充分性 联机清除率监测 透析时间 干体质量
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波尔山羊ACVRⅡB基因5′调控区多态性及其与初生体重体尺的关联分析
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作者 张晨俭 李隐侠 +5 位作者 钱勇 张俊 孟春花 王慧利 仲跻峰 曹少先 《畜牧与兽医》 CAS 北大核心 2023年第8期1-5,共5页
旨在探讨波尔山羊激活素受体ⅡB(activin A receptor typeⅡB,ACVRⅡB)基因5′调控区多态性及其对初生体重体尺的影响。从103只波尔山羊耳组织中提取基因组DNA,扩增ACVRⅡB基因5′调控区序列,测序鉴定SNPs位点,分析遗传多态性,并与波尔... 旨在探讨波尔山羊激活素受体ⅡB(activin A receptor typeⅡB,ACVRⅡB)基因5′调控区多态性及其对初生体重体尺的影响。从103只波尔山羊耳组织中提取基因组DNA,扩增ACVRⅡB基因5′调控区序列,测序鉴定SNPs位点,分析遗传多态性,并与波尔山羊初生体重、体尺进行关联分析。结果显示,鉴定到g.-1776C>G、g.-1725G>A、g.-1697C>T、g.-1604G>A、g.-1569G>C 5个SNPs位点,其中g.-1725G>A位点AA型在群体中频率为0.049,AG型为0.359,GG型为0.592,PIC为0.29,处于中度多态;g.-1569G>C位点CG型在群体中频率为0.167,GG型为0.833,PIC为0.14,处于低度多态。连锁分析发现g.-1725 G>A与g.-1697C>T、g.-1569G>C完全连锁(相关性为100%)。关联分析发现,g.-1725G>A位点AG型初生重、初生体长均显著高于GG型(P<0.05);g.-1569G>C位点CG型初生体高显著高于GG型。综上,g.-1725G>A位点可作为波尔山羊早期生长选育的候选分子标记。 展开更多
关键词 波尔山羊 ACVRⅡB基因 基因多态性 初生体重 初生体长
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新生儿重症监护病房极低出生体质量儿发展性照顾方法及其临床疗效
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作者 唐雯 刘山 《当代医学》 2023年第10期183-185,共3页
目的探讨新生儿重症监护病房(NICU)极低出生体质量儿发展性照顾方法及其临床疗效。方法选取2018年11月至2021年6月本院收治的74例极低出生体质量儿作为研究对象,其中2018年11月至2019年6月入院的患儿为对照组,2019年7月至2021年6月入院... 目的探讨新生儿重症监护病房(NICU)极低出生体质量儿发展性照顾方法及其临床疗效。方法选取2018年11月至2021年6月本院收治的74例极低出生体质量儿作为研究对象,其中2018年11月至2019年6月入院的患儿为对照组,2019年7月至2021年6月入院的患儿为实验组,每组37例。对照组采用常规护理,实验组采用发展性照顾,比较两组护理相关指标及护理前后生长发育情况。结果实验组平均睡眠时间长于对照组,恢复正常体质量时间、达到全肠内喂养时间均短于对照组,差异有统计学意义(P<0.05)。护理前,两组体质量、头围、身长比较差异无统计学意义;护理后,两组体质量高于护理前、身长均长于护理前,头围均大于护理前,且实验组体质量高于对照组、身长长于对照组,头围大于对照组,差异有统计学意义(P<0.05)。结论在NICU应用发展性照顾护理极低体质量儿,可缩短恢复正常体质量时间及达到全肠内喂养时间,延长睡眠时间,促进患儿身体正常发育,护理应用价值高,值得临床推广应用。 展开更多
关键词 新生儿重症监护病房 极低出生体质量儿 发展性照顾 体质量 头围 身长
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基于LSSA-XGBOOST改进算法的高体鰤鱼类体质量预测模型 被引量:1
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作者 俞国燕 左仁意 +2 位作者 严俊 罗樱桐 朱琪珩 《渔业研究》 2023年第5期427-437,共11页
为构建利用体质量判断的精准投喂模型,需实时获取鱼群体质量状态,基于LSSA-XGBOOST算法,通过对工船养殖实测的高体鰤(Seriola dumerili)体长、体宽和体质量数据进行分析,构建以体长、体宽两项体态特征数据为输入、体质量数据为输出的高... 为构建利用体质量判断的精准投喂模型,需实时获取鱼群体质量状态,基于LSSA-XGBOOST算法,通过对工船养殖实测的高体鰤(Seriola dumerili)体长、体宽和体质量数据进行分析,构建以体长、体宽两项体态特征数据为输入、体质量数据为输出的高体鰤体质量预测模型。结果显示,与常规数学模型拟合相比,LSSA-XGBOOST模型拟合的相关性系数R^(2)提高约10%;与传统BP神经网络和粒子群优化BP相比,LSSA-XGBOOST模型误差平方和R^(2)提升约3%,这为构建基于体质量判断的高体鰤精准投喂模型提供了理论依据。 展开更多
关键词 LSSA-XGBOOST 高体鰤 体长 体质量 关系
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鲇繁殖生物学特征分析
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作者 韩庆 刘可可 +3 位作者 黄艳飞 田汉 王文彬 刘良国 《南方水产科学》 CAS CSCD 北大核心 2023年第5期154-161,共8页
对沅江干流水域鲇(Silurus asotus)的生长与繁殖特征进行研究,为其种质资源的保护及合理利用提供科学依据。2018年5月至2020年4月在湖南省常德市沅江凌津滩库区采集到鲇738尾,对其体长体质量关系及繁殖特性进行分析。结果显示,鲇体长和... 对沅江干流水域鲇(Silurus asotus)的生长与繁殖特征进行研究,为其种质资源的保护及合理利用提供科学依据。2018年5月至2020年4月在湖南省常德市沅江凌津滩库区采集到鲇738尾,对其体长体质量关系及繁殖特性进行分析。结果显示,鲇体长和体质量呈幂函数关系,关系式为W=0.056L^(2.57)(R=0.97),幂指数b值为2.57,与理论匀速生长值3之间差异显著(P<0.05),群体生长为异速型,群体雌雄性比为1.21∶1。鲇群体肥满度平均为0.88,雌性平均0.94,雄性平均0.81,雌性极显著高于雄性(P<0.01)。性成熟系数雌性极显著高于雄性(P<0.01),雌性平均7.51,雄性平均1.85,均为5月最高、9月最低,雌、雄性成熟系数的周年变化趋势基本同步。卵径5月最高,达1626.5μm;5—8月逐步下降,其变化与实际产卵高峰期一致。个体平均绝对怀卵量为(29677±18174)粒,个体平均相对怀卵量为(107±65)粒·g^(−1)。绝对怀卵量与体质量和体长均成直线相关,关系式分别为:F=437.36W+945.09(R^(2)=0.93,P<0.01)和F=1205.38L−21285.27(R^(2)=0.87,P<0.01),从性成熟系数的周年变化推测,鲇的产卵高峰期为5月中旬至8月上旬。 展开更多
关键词 繁殖特性 体长体质量关系 生物学特性 沅江
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两个凡纳滨对虾家系体重与体长的关系 被引量:22
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作者 张灵侠 沈琪 +5 位作者 胡超群 张吕平 任春华 陈偿 梁泽廉 陈文林 《热带海洋学报》 CAS CSCD 北大核心 2006年第1期23-26,共4页
凡纳滨对虾Litopeneaus vannamei家系的培育是遗传选育种的基础,其生长特性包括生长速度、体重与体长的关系等,是家系的表型特征。报道了凡纳滨对虾2个家系的体长与体重的关系。通过回归分析,凡纳滨对虾家系1体重(W)与体长(L)的关系为:W... 凡纳滨对虾Litopeneaus vannamei家系的培育是遗传选育种的基础,其生长特性包括生长速度、体重与体长的关系等,是家系的表型特征。报道了凡纳滨对虾2个家系的体长与体重的关系。通过回归分析,凡纳滨对虾家系1体重(W)与体长(L)的关系为:W=0.0059L3.2809(R2=0.9931);家系2体重与体长的关系为:W=0.0059L3.2974(R2=0.9940),2个家系体重与体长的关系没有明显的变化,得出凡纳滨对虾体重与体长的关系为:W=0.0059L3.2895(R2=0.9934)。 展开更多
关键词 凡纳滨对虾Litopeneaus vannamei 家系 体长 体重 相互关系
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关于肥满度指数的讨论 被引量:71
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作者 戴强 戴建洪 +2 位作者 李成 刘志君 王跃招 《应用与环境生物学报》 CAS CSCD 北大核心 2006年第5期715-718,共4页
肥满度指数,也称身体状况指数,广泛应用于各个动物类群和生态学、生理、生化、遗传学以及养殖业.至今已有多种肥满度指数提出,从计算公式结构上,肥满度指数可以划分为比值法和残差法两大类.通过对各种肥满度指数的分析,Le Cren相对状态... 肥满度指数,也称身体状况指数,广泛应用于各个动物类群和生态学、生理、生化、遗传学以及养殖业.至今已有多种肥满度指数提出,从计算公式结构上,肥满度指数可以划分为比值法和残差法两大类.通过对各种肥满度指数的分析,Le Cren相对状态指数Kn、log10(体重)与log10(身体大小指数)线性回归的(标准化)残差这两种肥满度指数系统误差相对较小.实际应用中最好根据所考察的问题分别计算不同年龄段、性别的个体的肥满度指数来分析肥满度指数.由于定义的模糊性及其前提假设缺乏广泛验证,因此,肥满度指数在实际应用中需要谨慎考察其前提假设是否满足. 展开更多
关键词 肥满度 身体状况指数 体重-体长关系
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小黄鱼体长-体质量关系和肥满度的年际变化 被引量:71
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作者 李忠炉 金显仕 +1 位作者 单秀娟 戴芳群 《中国水产科学》 CAS CSCD 北大核心 2011年第3期602-610,共9页
根据1960-2010年渤海和黄海南部春季(4-5月)14个航次底拖网调查资料,采用体长对应平均体质量的方法和相对体质量法,按性别逐年拟合小黄鱼黄海北部-渤海群系和黄海南部群系雌雄群体的体长-体质量关系,计算肥满度,并分析其影响因子。结果... 根据1960-2010年渤海和黄海南部春季(4-5月)14个航次底拖网调查资料,采用体长对应平均体质量的方法和相对体质量法,按性别逐年拟合小黄鱼黄海北部-渤海群系和黄海南部群系雌雄群体的体长-体质量关系,计算肥满度,并分析其影响因子。结果显示,在多数年份内,小黄鱼雌雄个体间体长-体质量关系参数b无显著性差异(P>0.05);参数a和b呈极显著负相关关系(P<0.01),lga与b的比值受环境影响较小,可能与鱼体密度有关。小黄鱼黄海北部-渤海群系雌雄群体从1960年到2004年以等速生长为主,与1960年相比,参数b在资源严重衰退期和资源恢复初期(1982-1993年)有所增大;黄海南部群系雌雄群体从1960年到2010年以负异速生长为主,参数b在资源严重衰退期和资源恢复初期(1986-1994年)呈减小趋势,20世纪90年代后期开始逐渐升高。小黄鱼黄海北部-渤海群系雌雄群体的肥满度从1960年到2004年总体呈减小趋势;黄海南部群系雌雄群体1986年的肥满度极显著小于对应群体1960年的肥满度(P<0.01),此后略有升高,但年间差异不显著(P>0.05)。分析认为,在较好的饵料条件下,相对较低的捕捞压力是20世纪80-90年代初期小黄鱼黄海北部-渤海群系雌雄群体呈等速生长的主要原因;而持续的高捕捞压力引起群体中低龄鱼比例增加、体长生长速度加快是黄海南部群系呈负异速生长的主要原因。个体性成熟年龄减小是小黄鱼肥满度呈下降趋势的主要原因,但黄海伏季休渔管理和春季南黄海较高的水温,可能是20世纪90年代中期开始小黄鱼黄海南部群系各群体肥满度略有升高的原因。 展开更多
关键词 小黄鱼 体长-体质量关系 肥满度 年际变化 影响因子
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