黑叉尾海燕繁殖及迁徙的研究

黑叉尾海燕是海洋性鸟类,青岛沿海岛屿是其主要繁殖地之一。本文着重记述了其迁徙、分布、活动规律、繁殖习性、雏鸟生长等。１９８６、１９８７年共环志黑叉尾海燕２８０２只,１９８７年共回收环志鸟３９５只,其中春季２４７只,秋季１４８只;１９８６年环志的２５８只中回收到１２３只。两年的观察,该鸟５月１７￣３０日先后迁来,７月开始产卵,８月出雏。     

山西省代县小PiTi繁殖生物学的研究

１９８５－１９９４年的３－１１月,在山西省代县对小ＰｉＴｉ的繁殖生物学进行了研究。该鸟在山西省为夏候鸟,每年最虫３月６日迁来,最晚１１月２４日迁离,居留期为２５５天左右。种群密度在繁殖前的４月为１．３７,繁殖后的９月为１．９５（只／ｈａ）。产卵始期为５月２７日,日产１枚,窝卵数５－８枚,产出第二枚卵时开始孵卵。观察到最早孵卵期为５月２８日,孵卵期为２０－２２ｄ。雏鸟出壳先后顺序与产卵先后顺序相一致     

山西省代县小鸊鷉繁殖生物学的研究

１９８５—１９９４年的３—１１月,在山西省代县对小鸊鷉的繁殖生物学进行了研究。该鸟在山西省为夏候鸟,每年最早３月６日迁来,最晚１１月２４日迁离,居留期为２５５天左右。种群密度在繁殖前的４月为１．３７,繁殖后的９月为１．９５（只／ｈａ）。产卵始期为５月２７日,日产１枚,窝卵数５—８枚,产出第二枚卵时开始孵卵。观察到最早孵卵期为５月２８日,孵卵期２０－２２ｄ。雏鸟出壳先后顺序与产卵先后顺序相一致,孵化率为９５．４５％,雏鸟为早成鸟。     

广西龙虎山猕猴种群生态特征

１９８８～１９９５年,采用定点观察法和绝对计数与相对计数结合法对龙虎山猕猴种群生态作了调查研究。１９９０年核心区有猕猴１４群,５００只左右,猴群密度１．６群／ｋｍ２,种群密度５５．６只／ｋｍ２．猴群大小平均３３．８±２３．１（ｎ＝６）只。一般每隔４～５年分群一次,猴群群体年均增长率１４．８％,种群年均增长率为９．７％。猴群中成年猴性比为７．６±６．５（ｎ＝１２）,１～３岁组的性比为０．７４±０．６１（ｎ＝４）,群内未成年猴比例为６７．７±３．１％（ｎ＝１２）。发情交配期最早１１月１２日,最晚次年１月２０日,高峰期１２月上旬,持续３个月．产仔期最早４月１日,最晚８月１４日,高峰期５月上旬,持续时间４个半月．繁殖率４５．５％～１００％,平均７５．４±１３．２％（ｎ＝２１）。新生猴死亡率较低,新生猴性比（雌：雄）平均０．７４±０．３４（ｎ＝５）。     

若尔盖沼泽夏秀涉禽游禽观察

１９９１年５月２２日－６月１９日,笔者的若尔盖沼泽观察到涉禽,游禽２６种,隶属６目８科,其中：白翅浮鸥等１３种属若尔盖沼泽夏季新记录;黑颈鹤等１２种为繁殖鸟,绿头鸭等５种为若尔盖沼泽繁殖新记录;赤麻鸭、红脚鹬、普通燕鸥、灰雁等７种为优势种。调查区内共观察到黑颈鹤２３９只,估计整个若尔盖沼泽有黑颈鹤６１０只。建议在此建立面积２３．９万公顷的湿地保护管理区。     

若尔盖沼泽夏季涉禽游禽观察

１９９１年５月２２日－６月１９日,笔者在若尔盖沼泽观察到涉禽、游禽２６种,隶属６目８科,其中：白翅浮鸥等１３种属若尔盖沼泽夏季新记录;黑颈鹤等１２种为繁殖鸟,绿头鸭等５种为若尔盖沼泽繁殖新记录;赤麻鸭、红脚鹬、普通燕鸥、黑颈鹤、灰雁等７种为优势种。调查区内共观察到黑颈鹤２３９只,估计整个若尔盖沼泽有黑颈鹤６１０只。建议在此建立面积２３．９万公顷的湿地保护管理区。     

青海湖地区蓑羽鹤秋季迁徒的观察

１９８８年９月－１０月在青海湖泉湾观察迁飞蓑羽鹤５２群、６６４８只。迁飞途经该区始于９月１９日、终于１０月５日、历经１７天。迁飞时间主要集中在６：１０－１０：４０时、１６：００－２０：３０时,但以傍晚居多,占迁飞总数的５７．１３％。结群数在１７－３３４只之间,以５０－２３０只居多。迁飞方向为北东、北北东向西南、西南南和正南。鹤群排列成“人”、“Ｍ”字形,队形相对稳定并发出鸣叫。天气状况与迁飞的数量     

草兔繁殖生物学的初步研究

本文分析了１９９１年１－１０月获自山西省东南部丘陵山区以及１９９０－１９９３年１０月至翌年１月获自该省各地草兔的有关繁殖特征。草兔的繁殖季节为１－９月,雄性进入性活动的时间早于雌性。生殖腺测度有明显的季节变化,其峰值在４月和５月。当年兔３－４月龄时性可成熟,但达到性成熟月龄的当年兔只有５１．７％在７、８月参加繁殖。怀孕个体见于２－９月,３月怀孕率最高,此后逐渐下降。胎仔数１－７只,５月最多,年均值３．６只,每只雌兔年产幼兔１２．９只。     

洞庭平原黑线姬鼠繁殖特性研究

１９８６年１０月－１９９０年１０月在湖南省桃源县和汉寿县的稻作区逐月调查,夹捕黑线姬鼠长江亚种２７６８只,雌性占４５。６％。主要繁殖期３－１１月,研究期内的月平均怀孕率为４８．６±４．０％、平均胎仔数为５．３±０．２只。繁殖指数为２．３６±０．２９。以上３个参数及种群性性比有季节性变化,４－５月和７－１０月为２个妊娠高峰;雄性睾丸下位率和雌性怀孕率有同步变动的趋势。５年龄组之间,其性比、怀孕率和繁     

小毛足鼠繁殖生态研究

１９９１￣１９９５年每年４￣１０月的各月中旬,在内蒙古伊克昭盟达拉特旗沙地草场上,不同生态环境中共布放１０１８４５个夹日,捕获鼠６３２５只,其中小毛足鼠（Ｐｈｏｄｏｐｕｓ ｒｏｂｏｒｏｖｓｋｉｉ）２２１７只,占３５．０５％。根据胴体重划分成４个年龄组,５年总的性比为４９．６１％,接近１：１,无季节差异。雄性繁殖期为９个月（２￣１０月）,有年间差异。雌性繁殖力随着年龄的增长而增高,亚成年组、成年Ⅰ组     

Changes in lactate dehydrogenase activity in chicken tissues in hyperthyreosis in ontogenesis

The lactate dehydrogenase activity in reactions of lactate oxidation and synthesis was studied in subfractions of the chicken brain, heart and liver at the embryonal, early postembryonal and adult stages of development after thyroxine administration. It has been shown that during embryogenesis thyroxine predominantly enhanced the rate of lactate oxidation in the mitochondrial tissues. A marked increase in the lactate synthesis was found in cytoplasm of the adult chicken tissues. Specificity of enzyme activity alterations was detected in the chicken brain during ontogenesis after thyroxine administration.     

Scurvy in capybaras bred in captivity in Argentine

In order to determine if the absence of vitamin C in the diet of capybaras (Hydrochoerus hydrochaeris) causes scurvy, a group of seven young individuals were fed food pellets without ascorbic acid, while another group of eight individuals received the same food with 1 g of ascorbic acid per animal per day. Animals in the first group developed signs of scurvy-like gingivitis, breaking of the incisors and death of one animal. Clinical signs appeared between 25 and 104 days from the beginning of the trial in all individuals. Growth rates of individuals deprived of vitamin C was considerably less than those observed in the control group. Deficiency of ascorbic acid had a severe effect on reproduction of another population of captive capybaras. We found that the decrease in ascorbic acid content in the diet affected pregnancy, especially during the first stages. The results obtained suggest that it is necessary to supply a suitable quantity of vitamin C in the diet of this species in captivity.     

Role for dopamine in malonate-induced damage in vivo in striatum and in vitro in mesencephalic cultures

Defects in mitochondrial energy metabolism have been implicated in the pathology of several neurodegenerative disorders. In addition, the reactive metabolites generated from the metabolism and oxidation of the neurotransmitter dopamine (DA) are thought to contribute to the damage to neurons of the basal ganglia. We have previously demonstrated that infusions of the metabolic inhibitor malonate into the striata of mice or rats produce degeneration of DA nerve terminals. In the present studies, we demonstrate that an intrastriatal infusion of malonate induces a substantial increase in DA efflux in awake, behaving mice as measured by in vivo microdialysis. Furthermore, pretreatment of mice with tetrabenazine (TBZ) or the TBZ analogue Ro 4-1284 (Ro-4), compounds that reversibly inhibit the vesicular storage of DA, attenuates the malonate-induced DA efflux as well as the damage to DA nerve terminals. Consistent with these findings, the damage to both DA and GABA neurons in mesencephalic cultures by malonate exposure was attenuated by pretreatment with TBZ or Ro-4. Treatment with these compounds did not affect the formation of free radicals or the inhibition of oxidative phosphorylation resulting from malonate exposure alone. Our data suggest that DA plays an important role in the neurotoxicity produced by malonate. These findings provide direct evidence that inhibition of succinate dehydrogenase causes an increase in extracellular DA levels and indicate that bioenergetic defects may contribute to the pathogenesis of chronic neurodegenerative diseases through a mechanism involving DA.     

SSTR5 ablation in islet results in alterations in glucose homeostasis in mice

Somatostatin (SST) peptide is a potent inhibitor of insulin secretion and its effect is mediated via somatostatin receptor 5 (SSTR5) in the endocrine pancreas. To investigate the consequences of gene ablation of SSTR5 in the mouse pancreas, we have generated a mouse model in which the SSTR5 gene was specifically knocked down in the pancreatic beta cells (betaSSTR5Kd) using the Cre-lox system. Immunohistochemistry analysis showed that SSTR5 gene expression was absent in beta cells at three months of age. At the time of gene ablation, betaSSTR5Kd mice demonstrated glucose intolerance with lack of insulin response and significantly reduced serum insulin levels. Insulin tolerance test demonstrated a significant increase of insulin clearance in vivo at the same age. In vitro studies demonstrated an absence of response to SST-28 stimulation in the betaSSTR5Kd mouse islet, which was associated with a significantly reduced SST expression level in betaSSTR5Kd mice pancreata. In addition, betaSSTR5Kd mice had significantly reduced serum glucose levels and increased serum insulin levels at 12 months of age. Glucose tolerance test at an older age also indicated a persistently higher insulin level in betaSSTR5Kd mice. Further studies of betaSSTR5Kd mice had revealed elevated serum C-peptide levels at both 3 and 12 months of age, suggesting that these mice are capable of producing and releasing insulin to the periphery. These results support the hypothesis that SSTR5 plays a pivotal role in the regulation of insulin secretion in the mouse pancreas.     

2018年中国植物科学若干领域重要研究进展

2018年中国植物科学继续呈现快速发展的态势, 我国科学家在国际植物科学主流学术刊物发表论文数量大幅增加, 取得了多项具有重要影响的成果。调控植物生长-代谢平衡实现可持续农业发展入选2018年度中国科学十大进展; 中国被子植物区系进化历史研究入选2018年度中国生命科学十大进展。以水稻为代表的农作物和果蔬等经济作物研究在国际上已呈现出明显的优势, 若干领域已从“追赶”状态跨越到“领跑”地位。该文对2018年中国科学家在植物科学若干领域取得的重要研究成果进行了概括性评述, 旨在全面追踪和报道当前中国植物科学领域的发展前沿和热点, 展示中国科学家所取得的杰出成就。