凤头麦鸡繁殖行为观察

2006～2009年在黑龙江省牡丹江地区对凤头麦鸡Vanellus vanellus繁殖生态习性进行了观察.凤头麦鸡在牡丹江属夏侯鸟,每年3月末4月初迁来,9月下旬迁走,居留期约6个月;4月底开始筑巢,繁殖期间的配偶关系为一雄一雌,营巢于沼泽草甸,也有个体将巢筑于田边或荒地中,个别将巢直接筑在农田的垄上.巢比较简单,在1～2 d内完成.巢筑成后的7～10 d开始产卵.每窝4枚,平均卵重25.2 g,最后一枚卵产出后即开始孵卵,孵化期为24～29 d, 孵化率50%～100%;幼鸟为早成鸟,育雏期30 d左右.     

人工巢箱条件下白眉姬鹟的繁殖参数

2005～2006年,在吉林省左家自然保护区的次生林中,对人工巢箱条件下白眉姬鹟(Ficedulazanthopygia)的繁殖参数开展了初步研究.结果表明,人工巢箱中自眉姬鹟的窝卵数为5～7枚,平均6.0枚;卵重平均为1.6 g.卵大小平均为17.0 mm×13.1 mm.孵化期平均为13.1 d,每巢平均出雏5.4只,育雏期平均为12.8 d,每巢平均出飞雏鸟5.3只.白眉姬鹟的营巢成功率为70.0%,繁殖成功率为81.3%.     

河北南大港黑翅长脚鹬繁殖习性观察

2001年3～10月,在河北省南大港湿地和鸟类自然保护区对黑翅长脚鹬(Himantopus himantopus)的繁殖习性做了研究。该鸟在本地区为夏候鸟,3月下旬迁来,9月中旬迁离,居留期约180d。栖息生境主要在盐场,平均种群遇见率为40．8只／km.平均窝卵数4．1枚,孵化期为20-21d,孵化率为89．7％,年繁殖力为1．86,孵化期卵平均失重率为16．0％,幼鸟为早成鸟。     

北红尾鸲在浙江清凉峰国家级自然保护区的繁殖记述

2015年和2016年的5—7月,在浙江清凉峰国家级自然保护区野外调查期间发现一处北红尾鸲Phoenicurus auroreus巢址,并对其繁殖习性进行了观察。结果表明:北红尾鸲在本地为冬候鸟,但首次发现该种鸟类夏季在此繁殖;北红尾鸲的繁殖期为5月下旬至7月中旬,5月下旬开始营巢,持续10 d左右,巢穴外径7.5 cm×5.8 cm、巢深3.2 cm,巢材由苔藓、体羽、禾本科杂草茎等组成;6月中旬产卵,窝卵数为4~5枚(2015年产卵4枚、2016年产卵5枚),孵化期11~12 d,巢内育雏14 d。推测冬候鸟北红尾鸲在此繁殖可能与气候变化有关。     

山西芦芽山自然保护区戴胜繁殖生态初步观察

2003～2005年,在山西芦芽山国家级自然保护区对戴胜Upupa epops的繁殖生态进行了观察.戴胜在本区为夏候鸟,多在林缘耕地栖息,巢多筑于树洞中或岩隙岸堤的洞穴里,窝卵数6～7枚,卵均重4.1 g.孵化期17～18 d,育雏期26～28 d.     

黑卷尾的繁殖生态行为观察

2007～2009年每年5～7月对四川省绵阳地区黑卷尾Dicrurus macrocercus的繁殖生态进行了观察.结果 表明,在绵阳,黑卷尾5月初迁入,5月中旬开始筑巢,巢深(6.73±1.41)cm、巢位高(6.38±1.27)m,巢内径为(9.88±1.54) cm,外径为(12.87±2.75) cm;5月底6月初产卵, 窝卵数多为3～5枚,平均卵重4.61 g,平均卵长径24.4 mm,平均卵短径17.4 mm;孵卵期(16±1) d,育雏期15～17 d,在幼鸟8～12日龄亲鸟育雏频次最高,平均为(8.23±2.13) 次/d.     

江西吉安灰头麦鸡的繁殖生态研究

灰头麦鸡Vanellus cinereus在江西吉安地区是夏候鸟.2010 ～2011年对当地灰头麦鸡的繁殖生态进行了调查研究.结果表明,当地灰头麦鸡最早2月20日迁入,最晚9月17日迁离,居留时间约为7个月;3月初开始产卵,平均窝卵数3.8枚(n=14),平均卵大小48.0 mm×34.5 mm,平均卵重28.8 g(n =38);产满窝卵后即开始孵卵,孵卵由雌雄鸟共同承担;孵卵期为28 ～31 d;孵化率为90.15％.     

甘肃莲花山黑冠山雀繁殖生态的初步研究

2017和2018年每年的4至8月在甘肃莲花山国家级自然保护区,对人工巢箱中黑冠山雀（Periparus rubidiventris）的繁殖生态进行了研究。共悬挂100个巢箱,两年共计招引到15巢黑冠山雀。此外,还记录到4个自然巢,分别位于干枯的糙皮桦（Betula utilise）树洞（1巢）、土坡的缝隙（1巢）和路边水泥护坡的出水管中（2巢）。黑冠山雀雌雄亲鸟共同筑巢,巢内壁为兽毛夹杂少量绒羽,外壁为草茎须根和苔藓。5月中下旬为黑冠山雀的产卵高峰期,清晨产卵,日产1枚,产下最后1枚卵后开始孵卵。平均窝卵数为6枚（4 ~ 7 枚,n = 15）,平均卵重（1.12 ± 0.02）g,卵长径（15.30 ± 0.10）mm,卵短径（12.09 ± 0.11）mm（n = 86）。孵卵由雌鸟承担,孵卵期为15 d（14 ~ 16 d,n = 5）。产卵期,雌鸟离巢时有用巢材盖卵的行为,开始孵卵后则不再盖卵。双亲共同育雏,育雏期为16 d和17 d（n = 2）。所记录的18巢黑冠山雀的繁殖成功率为83.3%,人工巢箱（15巢）中繁殖成功率为86.7%,巢捕食者主要为鼠类。     

山西芦芽山自然保护区灰头鵐的繁殖记述

1998～2000年4～9月,对芦芽山自然保护区灰头的繁殖生态进行了考察.该鸟每年4月11日～14日迁来,居留期150～151天,5月下旬进入繁殖盛期.营巢期5～6天,窝卵数4～5枚,孵卵期11～12天,孵化率77.8%,离巢率85.7%,巢内育雏8～9天,巢外育雏6～7天.     

高黎贡山白尾梢虹雉繁殖生态观察

2002-2004年连续3个春季在高黎贡山自然保护区对白尾梢虹雉(Lophophorus sclateri)的繁殖习性进行了观察,对白尾梢虹雉的巢、卵和雏鸟进行了详细描述.在高黎贡山南段,白尾梢虹雉的产卵孵化始于3月底,止于5月初,窝卵数为2～3枚,孵卵期为28 d.窝卵数低、适宜巢址缺乏有可能是白尾梢虹雉种群增长缓慢...     

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.     

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.     

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.     

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.