Genetic parameters for chronic progressive lymphedema in Belgian Draught Horses

Genetic parameters for chronic progressive lymphedema (CPL)‐associated traits in Belgian Draught Horses were estimated, using a multitrait animal model. Clinical scores of CPL in the four limbs/horse (CPL_clin), skinfold thickness and hair samples (hair diameter) were studied. Due to CPL_clin uncertainty in younger horses (progressive CPL character), a restricted data set (D_3+) was formed, excluding records from horses under 3 years from the complete data set (D_full). Age, gender, coat colour and limb hair pigmentation were included as fixed, permanent environment and date of recording as random effects. Higher CPL_clin certainty (D_3+) increased heritability coefficients of, and genetic correlations between traits, with CPL_clin heritabilities (SE) for the respective data sets: 0.11 (0.06) and 0.26 (0.05). A large proportion of the CPL_clin variance was attributed to the permanent environmental effect in D_full, but less in D_3+. Date of recording explained a proportion of variance from 0.09 ± 0.03 to 0.61 ± 0.08. Additive genetic correlations between CPL_clin and both skinfold thickness and hair diameter showed the latter two traits cannot be used as a direct diagnostic aid for CPL. Due to the relatively low heritability of CPL_clin, selection should focus on estimated breeding values (from repeated clinical examinations) to reduce CPL occurrence in the Belgian Draught Horse.     

抑食肼对大型溞的急慢性毒性效应研究

选择21%抑食肼可湿性粉剂为受试农药,研究其对大型溞(Daphnia magna)的急性毒性和21 d慢性毒性效应,观察大型溞各个繁殖和生长指标变化,建立毒物剂量-反应关系,并寻找其中的敏感生物学指标。急性毒性试验结果表明,21%抑食肼可湿性粉剂对大型溞的48 h-EC50为0.94 mg·L-1;慢性毒性试验结果表明,抑食肼对大型溞的初次蜕壳时间、蜕壳次数、产卵时间、产幼溞数和产幼溞胎数等都有显著的影响,其中,0.135 mg·L-1的暴露浓度可以显著减少大型溞蜕壳次数、产幼溞总数量和产幼溞胎数,综合各个繁殖毒性终点指标,21 d无可见效应浓度(NOEC)为0.045 mg·L-1。此外,研究还发现低至0.015 mg·L-1的抑食肼暴露21 d可以使母溞体长显著性下降。研究结果表明,抑食肼胁迫在一定程度上对大型溞的生长和繁殖具有抑制效应。     

AQP-4在抑郁模型大鼠海马区含量的改变

目的探讨抑郁模型大鼠海马区AQP-4含量的改变．方法通过采用慢性不可预见性刺激和孤养相结合的方法,在应激前1天和应激第22天后对大鼠行为学观测,快速断头取海马组织,通过半定量PCR方式观察海马区AQP-4含量的变化．结果发现抑郁大鼠海马区AQP4mRNA的相对含量增加．结论AQP-4既参加调节抑郁模型大鼠海马区内环境,同时对抑郁模型大鼠海马区神经元的凋亡发挥作用,为研究抑郁症的发病机制奠定基础．     

Recording cerebellar neuron activities in swimming goldfish

ABSTRACT:   Neuronal activities were investigated in the cerebellum of immobilized and swimming goldfish Carassius auratus . Extracellularly recorded neural activities of the cerebellum in immobilized goldfish were characterized and classified into five types. Based on the waveforms and recording depths, these five neural activity types were estimated to originate from three identified classes of cerebellar neurons: Purkinje cells, eurydendroid cells, and granule cells. Chronic recording of cerebellar neuron activities in unrestrained goldfish was performed for more than 100 h. During the chronic recordings, a submersible amplifier attached to the goldfish head, and a multielectrode array developed for the present study were used. Neuronal activities in the cerebellum of free-swimming fish could also be classified into five types as in the immobilized condition. Firing patterns of two neurons identified as Purkinje cells and eurydendroid cells were analyzed during turning movements of the goldfish. The firing patterns of these neurons changed in relation to turning movements. Although some improvements are required, the chronic recording method developed in the present study can be applied to further investigations concerning the direct relationship between brain neural activities and certain behavior.     

以鲥为瘟:古代长江鲥鱼的污名化

鲥鱼在明清一些著作中被称为瘟鱼。历来关于瘟鱼的解释主要围绕鲥鱼本身来阐发,但这些观点不能很好地解释鲥鱼为何会在江西、两湖以及四川一带被称作瘟鱼,而在盛产鲥鱼的江东却没有这种指称。明人的“瘟鱼”观点源自唐人孟诜“发疳、痼”的说法,李时珍所说的蜀地瘟鱼并不是鲥鱼。一些清人认为瘟鱼并非来自鲥鱼本身。《见闻录》中记载了一个鲥鱼被虚构成瘟鱼的故事,揭示出瘟鱼是后人将瘟疫附会到鲥鱼身上的结果。显然,鲥鱼在特定地点被称为瘟鱼,是鲥鱼与地方文化结合的产物。     

实验性慢性氟中毒家兔肝、肾动态超微病理学研究

２４只２０～３０日龄体重０．７～１．２ｋｇ新西兰白兔随机分为实验组１５只（每日每只随饮水摄取ＮａＦ４５ｍｇ／ｋｇ体重）及健康对照组９只（饮用自来水）．两组在相同饲养管理条件下实验观察．分别在实验第３０，６０．９０ｄ时迫杀，对肝和肾进行超微病理学研究．结果表明，肝和肾实质细胞膜系统损伤明显，胶原原纤维再生增多，且有再生障碍及再生后的损伤性变化．     

Combined decongestive therapy including equine manual lymph drainage to assist management of chronic progressive lymphoedema in draught horses

Equine chronic progressive lymphoedema (CPL) is a disabling disorder of draught horse breeds. Combined decongestive therapy (CDT) is the treatment of choice for lymphoedema in man and has been adapted for use in horses. Equine CDT, which includes manual lymph drainage (MLD) and subsequent bandaging with short stretch bandages, was expected to improve the signs of CPL in draught horses because CPL resembles primary lymphoedema in man. Five affected horses ‐ Gypsy cob (n = 1), Clydesdale (n = 1), Shires (n = 3) ‐ were included. Lesions were documented pre‐ and post treatment. Percentage volume loss of the distal legs was calculated using the disc model. Initial plans for daily CDT had to be adapted; intermittent treatment of Chorioptes infections required alternating between CDT and MLD in 4/5 horses. Concurrent pyoderma (1/5 horses) was treated throughout the study. Development of unrelated lameness (hoof abscess) allowed limited CDT treatment only in one horse. Marked softening of previously firm tissue indicated the change from ‘brawny’ to pitting oedema in 2/5 horses. Fibrotic nodules and folds in the pasterns became markedly softened and smaller in 2/5 horses. Skin surface notably improved in all horses: hyperkeratosis decreased, erosions and ulcerations healed completely and crusts disappeared. After 2 weeks, a mean volume reduction of 11.25% was seen, ranging from 4.75–21.74% and quality of movement improved. This pilot study documents evidence that CDT assists management of CPL. Current CPL management is limited to palliative treatments of secondary infections. Whilst not a permanent treatment, CDT offers a promising tool to manage horses with CPL, improving their quality of life and potential usefulness. More extensive and prolonged studies with a larger number of horses are warranted to evaluate the full potential of CDT.