原尾蜥虎的选择体温、热耐受性和食物同化的热依赖性

(Tsel)、热耐受性和体温对食物同化的影响。Tsel无显著的日时间变化,两性个体的Tsel、临界低温(CTMin)和临界高温(CTMax)无显著的差异。Tsel、CTMin和CTMax的平均值分别为30.9℃、3.2℃和43.3℃。体温对动物食物通过时间有显著的影响。在25℃-33℃范围内,食物通过时间随体温升高而缩短;体温超过33℃后,食物通过时间随体温升高而延长。温度对原尾蜥虎的摄食量、表观消化系数(ADC)和同化效率(AE)有显著的影响。在25℃-37℃范围内,动物在低体温下(25℃和27℃)的摄食量、ADC和AE小于更高体温下动物的对应数值。种间比较结果显示,原尾蜥虎是生活于南方的蜥蜴中具有较强耐受极端体温的种类。     

桂林地区克氏原螯虾对泽蛙蝌蚪的捕食

克氏原螯虾（Procambarus clarkii）已入侵我国江苏、湖北、江西、安徽等多个省（市）。为研究克氏原螯虾对其生境中主要两栖动物泽蛙（Rana limnocharis）的影响,我们于2006年5-6月对广西桂林地区自然生境中克氏原螯虾和泽蛙蝌蚪的数量和密度进行了调查,7月在室内进行了克氏原螯虾对泽蛙蝌蚪和饰纹姬蛙（Microhyla ornata）蝌蚪的捕食实验。野外调查结果表明克氏原螯虾的密度与泽蛙蝌蚪的密度呈显著负相关。室内实验结果表明克氏原螯虾对泽蛙蝌蚪的捕食强度与克氏原螯虾体长呈显著正相关,且对泽蛙蝌蚪的捕食强度高于饰纹姬蛙蝌蚪。表明克氏原螯虾对两栖类幼体有比较严重的危害,应加强监测,采取相应措施预防和控制其危害。     

杀虫剂敌敌畏和除草剂丁草胺对饰纹姬蛙蝌蚪的急性毒性实验

采用静态换水法研究了杀虫剂敌敌畏、除草剂丁草胺对饰纹姬蛙(Microhyla ornata)蝌蚪的急性毒性影响。结果表明,杀虫剂敌敌畏对饰纹姬蛙蝌蚪的24-h、48-h的半致死浓度(LC50)分别为3．91μl／l和1．97μ/l;除草剂丁草胺对饰纹姬蛙蝌蚪的24-h LC50和48-h LC50分别为3．37μl／1和1．88μl／1,饰纹姬蛙蝌蚪对丁草胺的敏感性稍大于敌敌畏。     

粤北山区饰纹姬蛙胚后发育的初步观察

初步观察记录了饰纹姬蛙Microhyla ornata胚后发育过程。饰纹姬蛙的卵采于广东韶关小坑国家森林公园,置于人工实验缸中自然孵化,在23.0～28.7℃水温条件下观察饰纹姬蛙蝌蚪胚后发育的过程。该蛙的胚后发育可以分为19期,历时31.1d,对其后肢芽、趾、前肢的发育,以及肛管及尾的变化等方面做了系统的描述,饰纹姬蛙蝌蚪的头长、体长、尾长和后肢长度随发育时间的增加而显著增长。     

饰纹姬蛙的人工驯养与繁殖

2015年7月—2017年5月,对饰纹姬蛙Microhyla fissipes的人工驯养体系(饲养环境和饵料选择等)和繁殖(繁殖行为和人工催产等)开展了相关研究。观察发现,饰纹姬蛙繁殖期为3—10月,其中,5—8月为繁殖高峰期;同一对亲本每年可繁殖5次,2次繁殖间隔时间最短为16 d;卵团含卵量为15~1 100枚(310枚±203枚,n=98),与雌性亲本的体质量显著正相关(R~2=0.44,P0.001,n=76)。在人工驯养过程中初步建立了良好的饲养管理体系,其中饵料体系是"熟蛋黄-螺旋藻粉(饲喂蝌蚪)-跳虫(饲喂刚变态的幼蛙)-残翅果蝇(饲喂亚成体和成体蛙)",同时获得了饰纹姬蛙人工催产的最佳实验条件。该成果不仅可为饰纹姬蛙的研究工作提供适宜的实验材料,促进该物种的模式化进程,也可为无尾两栖动物的实验室驯化提供参考。     

金线侧褶蛙和泽陆蛙的两性异形与生育力

比较金线侧褶蛙和泽陆蛙的两性异形和生育力,首次通过种间比较来验证生育力选择理论是否能解释两栖动物两性异形的进化。金线侧褶蛙和泽陆蛙均为雌体大于雄体的两性异形类型,其两性异形程度存在显著差异,金线侧褶蛙两性异形程度指数为0 .30 ,而泽陆蛙仅为0 .0 8。然而,两者的怀卵量无显著差异。因此,结果与生育力选择理论预测不一致。此种不一致性可能由下述原因导致:选择压力作用于雄体而非雌体、能量分配策略和死亡率的种间差异、以及系统发育历史的种间差异。金线侧褶蛙和泽陆蛙雄体的身体状态指数显著高于雌体。金线侧褶蛙的头,眼和四肢都显著大于泽陆蛙;两者雌体的前后肢长度显著大于雄体。两性金线侧褶蛙的前后肢随体长呈同速生长,而泽陆蛙的前后肢随体长呈异速生长     

温度对饰纹姬蛙蝌蚪生长的影响

为揭示温度对饰纹姬蛙(Microhyla fissipes)蝌蚪生长的影响,将同一家系发育至28期的45只蝌蚪随机均分为3组,每组15只,分别置于水温25、28、30℃条件下饲养,测定其全长、体宽、眼距、吻长及头体长5项形态指标,分析不同温度下各项形态指标的变化。结果显示,5项形态特征有基本一致的变化趋势,其中全长最易表征蝌蚪的生长状况。从全长看,25℃组蝌蚪生长发育缓慢,但在12 d后有加快的趋势;30℃组在饲养第3~12 d,生长最迅速(增长率β=50.05%),但在12 d后生长明显变缓(β=9.42%),而到28 d时,已有较多蝌蚪死亡(5/15);28℃组的蝌蚪生长发育态势最好,且在饲养第28 d均超过30℃组,其在3 d后加快的生长趋势也强于25℃组。其他4项指标与全长有类似的结果。综合结果分析表明,30℃下蝌蚪在后期(21 d后)的成活率明显降低,而25℃下其生长缓慢,提示28℃是饰纹姬蛙蝌蚪比较适合的饲养温度。     

河南省发现合征姬蛙

报道了采自河南商城县的一种姬蛙科标本,与河南已记载的饰纹姬蛙(Microhyla arnata)比较差异显著,经鉴定为合征姬蛙(M.mixtura)。该蛙在河南商城的发现,说明其分布范围不仅仅限于几个地区,可能为连续的带状分布。     

泽蛙、日本林蛙、饰纹姬蛙不同地理居群的核型多样性

本文研究了温州地区的泽蛙、日本林蛙、饰纹姬蛙的核型,并分析了9个地理居群泽蛙的核型、4个地理居群日本林蛙的核型和3个地理居群饰纹姬蛙的核型。结果表明,不同地理居群的同种蛙均有相同的染色体数和核型模式。泽蛙、日本林蛙都为 2n=26,NF=52,核模式5＋8;饰纹姬蛙 2n=24,NF=48,核模式6＋6。但同一种蛙的不同地理居群之间在SM数目和顺序、次缢痕或随体的位置等都有所不同,说明不同地理居群的同种蛙的染色体具有丰富的多样性。故保护蛙品种资源多样性,不仅要从整个群体上考虑,而且要针对每个品种（或类群）进行保护。 Abstract：The karyotypes of Rana limmocharis boie,Rana j.Japonica,and Microhyla ornata from Wenzhou were studied.The karyotypes of nine populations of Rana limmocharis boie,four populations of Rana j.Japonica and three populations of Microhyla ornata from different geographical regions were compared.The results demonstrated that the same species of different geographical populations have the same amount of chromosome and karyotypic formulae. Rana limmocharis boie and Rana j.Japonica have 2n=26,NF=52 and 5＋8 karyotypic formulae.Microhyla ornata has 2n=24,NF=48 and 6＋6 karyotypic formulae.But some dissimilarities were found among them.First,the number and sequence of submetacentric chromosome were different among them,and then the secondary contriction （SC）or satellite （Sat）were also different.It was showed that the chromosomes of same species of different geographical population have diversities.Conservation of frog genetic diversity must be considered of not only the genetic diversity conservation of the total frog population but also that of every frog breed.     

Northern grass lizards (<Emphasis Type="Italic">Takydromus septentrionalis</Emphasis>) from different populations do not differ in thermal preference and thermal tolerance when acclimated under identical thermal conditions

We acclimated adults of Takydromus septentrionalis (northern grass lizard) from four localities (populations) under identical thermal conditions to examine whether local thermal conditions have a fixed influence on thermal preference and thermal tolerance in the species. Selected body temperature (Tsel), critical thermal minimum (CTMin), and critical thermal maximum (CTMax) did not differ between sexes and among localities in lizards kept under identical laboratory conditions for ∼5 months, and the interaction effects between sex and locality on these measures were not significant. Lizards acclimated to the three constant temperatures (20, 25, and 35°C) differed in Tsel, CTMin, and CTMax. Tsel, CTMin, and CTMax all shifted upward as acclimation temperature increased, with Tsel shifting from 32.0 to 34.1°C, CTMin from 4.9 to 8.0°C, and CTMax from 42.0 to 44.5°C at the change-over of acclimation temperature from 20 to 35°C. Lizards acclimated to the three constant temperatures also differed in the range of viable body temperatures; the range was widest in the 25°C treatment (38.1°C) and narrowest in the 35°C treatment (36.5°C), with the 20°C treatment in between (37.2°C). The results of this study show that local thermal conditions do not have a fixed influence on thermal preference and thermal tolerance in T. septentrionalis.     

Critical thermal maxima and minima of Macrobrachium rosenbergii (Decapoda: Palaemonidae)

1. Critical thermal maxima (CTMax) and minima (CTMin) were determined for postlarvae and juveniles of Macrobrachium rosenbergii acclimated at 20, 23, 26, 29 and 32±1°C. 2. At each acclimation temperature the CTMax and CTMin for postlarvae were 37.3, 38.3, 39.0, 41.0, 41.6°C and 10.0, 11.0, 13.0, 14.8, 16.8°C respectively and for juveniles 36.5, 38.4, 39.2, 41.5, 42.0 and 10.5, 11.3, 13.3, 14.6, 16.4°C respectively. 3. We found no indication of significant differences (P>0.05) in the CTMax and CTMin of the prawn postlarvae and juveniles. 4. The zone of thermal tolerance base on the CTMax and CTMin boundaries for postlarvae was 821.2°C² and 816.9°C² for juveniles, showing a high degree of eurythermality. To cultivate this species it should be done in no less than 16°C (CTMin) and below 42°C.     

Thermal tolerance of European Sea Bass (Dicentrarchus labrax) juveniles acclimated to three temperature levels

This study was carried out to determine upper (CTMax) and lower (CTMin) thermal tolerance, acclimation response ratio (ARR) and thermal tolerance polygon of the European sea bass inhabiting the Iskenderun Bay, the most southeasterly part of the Mediterranean Sea, at three acclimation temperatures (15, 20, 25 °C). Acclimation temperature significantly affected the CTMin and CTMax values of the fish. At 0.3 °C min⁻¹ cooling or heating rate, CTMin ranged from 4.10 to 6.77 °C and CTMax ranged from 33.23 to 35.95 °C in three acclimation temperatures from 15 to 25 °C. Thermal tolerance polygon for the juveniles at the tested acclimation temperatures was calculated to be 296.14 °C². In general, the current data show that our sea bass population possesses acclimation response ratio (ARR) values (0.25-0.27) similar to some tropical species. The cold tolerance values attained for this species ranged from 4.10 to 6.77 °C, suggesting that cold winter temperatures may not pose danger during the culture of European sea bass in deep ponds or high water exchange rate systems. Upper thermal tolerance is more of a problem in the southern part of the Mediterranean as maximum water temperature in ponds may sometimes exceed 33-34 °C, during which underground cool-water should be used to lower ambient water temperature in the mid-summer. For successful culture of sea bass in ponds, temperature should be maintained around 25 °C throughout the year and this can be managed under greenhousing systems using underground well-waters, commonly available in the region.     

Thermal acclimation and hardening in tadpoles of the bullfrog, Rana catesbeiana

1. 1.|Critical thermal maxima (CTMax) and minima (CTMin) were measured to evalute thermal hardening in Rana catesbeiana.

2. 2.|Tadpoles show heat hardening and CTMax acclimation, and both responses are influenced by developmental stage.

3. 3.|The first evidence of cold hardening in vertebrates is reported here.

4. 4.|Heat hardening significantly reduces cold tolerance, but there is otherwise no evidence of a cross-hardening effect.

华北丽斑麻蜥食物同化和疾跑速的热依赖性

作者研究山西阳泉丽斑麻蜥(Eremias argus)成体的选择体温、热耐受性及食物同化和疾跑速的热依赖性。选择体温、临界低温和临界高温无显著的两性差异,分别为36·0℃、1·0℃和44·9℃。在实验温度范围内,体温显著影响食物通过时间、日摄食量、日粪尿排量、表观消化系数和同化效率。食物通过时间在26 -34℃范围内随体温升高而缩短,在更高的体温下则延长。蜥蜴在30、32、34和36℃体温下明显摄入较多的食物、排出明显较多的粪尿。34℃和36℃下的表观消化系数和同化效率大于其它更低或更高温度下的对应数值,但这两个变量未因体温变化而呈现清晰的规律性变化。疾跑速在18 -36℃范围内随体温升高而加快,在38℃体温下则减缓。36℃或附近体温最适合疾跑速。疾跑速最适体温接近蜥蜴的选择体温,表明蜥蜴疾跑速的最适温度可能与其选择体温密切相关[动物学报52 (2) : 256 -262 , 2006]。     

Thermal tolerance of Litopenaeus vannamei (Crustacea: Penaeidae) acclimated to four temperatures

Critical thermal minima (CTMin) and maxima (CTMax) values were determined for the Pacific white shrimp Litopenaeus vannamei post-larvae and juveniles at four different acclimation temperatures (15, 20, 25, and 30 °C). The CTMin of shrimp at these acclimation temperatures were 7.82, 8.95, 9.80, and 10.96 °C for post-larvae and 7.50, 8.20, 10.20, and 10.80 °C for juveniles, respectively, at 1 °C h⁻¹ cooling rate. The CTMax values were 35.65, 38.13, 39.91, and 42.00 °C for post-larvae and 35.94, 38.65, 40.30, and 42.20 °C for juveniles at the respective acclimation temperatures. Both acclimation temperature and size of the shrimp affected CTMin values of L. vannamei (P<0.01). Overall, juveniles displayed significantly lower CTMin values than the post-larvae (P<0.0001). However, the CTMax response by post-larvae and juveniles were not significantly different from each other and no interaction was determined between the acclimation temperature and development stage (P>0.01). The area of the thermal tolerance polygon over four acclimation temperatures (15, 20, 25, and 30 °C) for the post-larvae of L. vannamei was calculated to be 434.94 °C². The acclimation response ratio (ARR) values were high ranging from 0.35 to 0.44 for both post-larvae and juveniles. L. vannamei appears to be more sensitive to low temperatures than other penaeid species and its cold tolerance zone ranged from 7.5 to 11 °C. In successful aquaculture temperature must never fall below 12 °C to prevent mortalities. Upper thermal tolerance is less of a problem as in most subtropical regions maximum water temperature rarely exceeds 34 °C, but care should be given if shallow ponds with low water renewal rate are being used.     

虎纹蛙选择体温和热耐受性在个体发育过程中的变化

体温是影响变温动物表现的最重要生理学变量。检测了国家二级保护动物虎纹蛙的雌性亚成体、雄性亚成体、幼体和蝌蚪这4个发育阶段的选择体温和热耐受性。单因子方差分析表明,虎纹蛙选择体温、耐受低温、耐受高温和温度耐受范围的组间差异均显著,幼体的选择体温(24.13℃)显著低于雌性亚成体(28.06℃)、雄性亚成体(29.27℃)和蝌蚪(28.23℃),雌性亚成体、雄性亚成体和蝌蚪之间差异不显著;幼体的耐受低温(13.85℃)显著高于雌性亚成体(11.27℃)、雄性亚成体(10.84℃)和蝌蚪(10.74℃),雌性亚成体、雄性亚成体和蝌蚪之间差异不显著;幼体具有显著低的耐受高温(35.48℃)、蝌蚪具有显著高的耐受高温(43.31℃),雌性亚成体(39.55℃)和雄性亚成体(39.02℃)的耐受高温差异不显著;幼体(21.62℃)具有显著小的温度耐受范围、蝌蚪(32.58℃)具有显著大的温度耐受范围,雌性亚成体(28.28℃)和雄性亚成体(28.18℃)的温度耐受范围差异不显著。虎纹蛙幼体和亚成体体温和水温之间在降温速度和升温速度的相关关系均显著。用回归剩余值去除水温变化速度对体温变化的影响,双因子方差分析(降温和升温速度为重复检验设置)表明,幼体的体温变化速度显著大于亚成体,两性亚成体间差异不显著;温度变化类型(降温和升温)和两因子的交互作用对体温变化的影响不显著。基本热生态位分离和体温调节能力的发育限制是形成上述现象的最可能的原因。     

Effect of Body Size on Reef Fish Tolerance to Extreme Low and High Temperatures

Understanding the thermal physiology of tropical marine organisms has become an issue of major interest due to the potential impact of current global changes in temperature. In this study we report the effect of body size on the thermal tolerance (as critical thermal maximum (CTMax) and minimum (CTMin)) of seven reef fish species from Gorgona Island (tropical eastern Pacific Ocean). Within the studied species we found little variation in CTMax and CTMin among fishes ranging from juveniles to adults. This suggests that thermal tolerance of small tropical reef fishes is not significantly affected by differences in body size. The reduced intra-specific variation in thermal tolerance found in these species also suggests a limited capability to adapt to extreme thermal conditions and raises concerns regarding current global changes in temperature.     

Thermal sensitivity of a Neotropical amphibian (Engystomops pustulosus) and its vulnerability to climate change

A species’ thermal sensitivity and its exposure to climate variation are key components in the prediction of its vulnerability to climate change. We tested the thermal sensitivity of a tropical amphibian that lives in a mild constant climate in which the thermal tolerance range is expected to closely match the experienced environmental temperature. The air temperature that this species is exposed to varies between 21.9 and 31.6°C with an annual mean of 27.2°C. We estimated the microhabitat water temperature variation under vegetation shade, which buffers the temperature by 1.8°C in relation to that of the air, and with open canopy, where the water was 1.9°C warmer than the air temperature. With broods of tadpoles split into five treatments (15°C, 21°C, 28°C, 31°C, and 33°C), we estimated the critical thermal maximum (CTMax) and critical thermal minimum (CTMin) after at least 7 days of acclimation. Both CTMax (42.3°C) and CTMin (11.8°C) were more extreme than the temperature range estimated for the field. We estimated the optimum temperature (T_o = 28.8°C) and the thermal performance breadth (range: 23.3–34.1°C) based on growth rate (g/day). The animals were able to acclimate more extensively to cold than to warm temperatures. These performance curve traits closely matched the air temperature. The estimated vulnerability varied according to the microhabitat prediction model used. The combination of tadpole data on thermal sensitivity and macro‐ and microhabitat variation provides a necessary framework to understand the effects of climate change on tropical amphibians.