Percentage of Ubiquitinated Spermatozoa does not Correlate with Fertilizing Capacity of Thawed Bovine Semen     

I Rodríguez‐Lozano  A Ávalos‐Rodríguez  H Castillo‐Juárez  F Borderas‐Tordesillas  JJ Roa‐Vidal  AM Rosales‐Torres 《Reproduction in domestic animals》2014,49(1):27-31

In the spermatozoa of some species, the ubiquitin–proteasome system detects altered proteins and tags them for elimination by the proteasome. In some species' ejaculates, a high proportion of ubiquitinated spermatozoa (i.e. those having ubiquitin bound to the altered or damaged membrane proteins) has been related to infertility. The aim of this study was to assess whether the percentage of ubiquitinated spermatozoa relates to fertility of dairy bulls and whether ubiquitination increases during protein remodelling that occurs during in vitro spermatic capacitation. Thirty‐two frozen semen straws from four high‐fertility (ReproMax^®) and four normal‐fertility (Normal) Holstein‐Friesian sires were evaluated. Ubiquitinated and capacitated spermatozoa were quantified by sperm ubiquitin tag immunoassay and chlortetracycline stain, respectively. Fertilizing capacity of sires was assessed by in vitro fertilization. No differences were found between Normal and ReproMax^® sires with regard to the observed percentage of ubiquitinated spermatozoa (42.97 ± 3.69% and 49.68 ± 9.27%, respectively; p > 0.05). Additionally, no differences were found in the percentage of ubiquitinated spermatozoa as a consequence of spermatic capacitation in either Normal (42.97 ± 3.69% before capacitation vs 44.67 ± 7.5% after; p > 0.05) or ReproMax^® sires (49.68 ± 9.27% before vs 45.05 ± 7.51% after; p > 0.05). The percentage of ubiquitinated spermatozoa in a thawed sperm samples did not correlate with its in vitro fertilizing capacity; thus, this assay does not prove useful to detect in vivo fertility differences between sires. Additionally, protein degradation occurring during remodelling of the spermatozoon plasma membrane during the capacitation process does not seem to involve the ubiquitin–proteasome system.  相似文献   

Seeking Mathematical Strategies in Sperm Function Analysis: Between Scylla and Charybdis?     

AM Petrunkina  A-R Günzel-Apel  E Töpfer-Petersen 《Reproduction in domestic animals》2003,38(2):125-133

During the last decades, essential progresses in reproductive biotechnology were achieved, implying development of special spermatological techniques. The major problem was to set up simple, rapid, precise and adequate evaluation methods. The key aspect to be considered in all assays of sperm fertilizing function is capacitation. As not all spermatozoa respond to fertilizing conditions in a similar manner, it seems to be logical to assess samples via their response to these specific conditions. For the spermatological practice, the sensitivity of methodology for assessment and analysis of data with respect to differences in individual response, in heterogeneity of the population, and proper temporal characterization of the response is crucial for the improvement of evaluation procedures. Currently, most used statistical analytical tools in spermatology do not always fulfil these essential sensitivity requirements. We structured our paper concerning different fields of mathematical science (distribution analysis, fractal geometry, functional approximation and differentiation) related to the modern insights in sperm function analysis. The spectrum of methods we are going to review in this paper is restricted to basic ideas to illustrate how the accuracy and sensitivity of sperm evaluation assays may be improved by applying adequate elementary tools of the mathematical analysis.  相似文献   

Dicoumarol toxicity in cattle associated with ingestion of silage containing sweet vernal grass (Anthoxanthum odoratum)     

DJ RUNCIMAN  AM LEE  KFM REED  JR WALSH 《Australian veterinary journal》2002,80(1):28-32

A diagnosis of dicoumarol toxicity in a herd of Friesian cattle was made following investigation of the deaths of three mature cows and eleven yearling heifers. Affected stock had been fed wrapped, bailed silage containing approximately 90% sweet vernal grass ( Anthoxanthum odoratum ). Sweet vernal grass contains coumarin, which can be converted to dicoumarol, a vitamin K antagonist, through the action of moulds. Most deaths were preceded by lethargy, severe anaemia and subcutaneous and internal haemorrhage. Dicoumarol toxicosis was suspected based on clinical signs, necropsy findings and prolonged prothrombin and activated partial thromboplastin times. Dicoumarol analysis of blood from affected animals and silage confirmed the diagnosis.  相似文献   

崩岗堆积土体渗透特性及剖面水分特征——以广东省五华县莲塘岗崩岗为例   总被引：2，自引：0，他引：2  

张大林  刘希林 《水土保持通报》2015,35(2):251-256,262

[目的]崩岗内部堆积土体是侵蚀的主要物质来源。通过对其渗透过程进行研究,揭示其中的规律性,探索崩岗的侵蚀机理。[方法]采用自制双环渗水试验装置,结合PR2/6土壤剖面水分测定仪,在广东省五华县莲塘岗崩岗野外现场进行渗水试验。[结果](1)崩积锥稳渗率在0.58~2.41mm/min之间,3个试验点平均稳渗率为1.37mm/min,沟道土体平均稳渗率高达5.58mm/min,渗透过程以重力流为主,土体结构稳定;(2)入渗速率与时间成负指数幂函数关系,符合Kositakov模型;(3)初始含水率越高,湿润锋移动速度越快,影响范围越深,稳渗时湿润锋深度在600~1 000mm及以上;(4)土体剖面含水率分布受土体非均质性的影响,自上而下呈波动式下降。[结论]崩岗堆积土体最大失稳深度至少为600~1 000mm,甚至可以达到1 000mm以上,崩积锥的非均质性具有阻渗作用,易形成滞水层并发生潜蚀,对崩岗侵蚀过程产生影响,是渗透研究的重点。  相似文献   

四川桃树螺旋线虫的记述     

兰庆渝  赵学谦 《河北农业大学学报》1996,19(3):18-23

记述了四川７种桃树螺旋线虫，其中除Ｈｅｌｉｃｏｔｙｌｅｎｃｈｕｓｄｉｇｉｔｉｆｏｒｍｉｓ已有报道外，其余６种国内未见正式报道。  相似文献   

A Field Study on Group Housing of Lactating Sows with Special Reference to Sow Health at Weaning     

F. Hultn  N. Lundeheim  A.-M. Dalin  S. Einarsson 《Acta veterinaria Scandinavica》1995,36(2):201

Four farms that group-housed sows from 2 weeks of lactation until weaning (G-farms) and 3 farms that kept the sows individually penned throughout the 5 to 6-week-long lactation period (C-farms), were compared in terms of sow health. All sows were crossbred Swedish Yorkshire × Swedish Landrace. The daily food ration was similar on all farms except during the group-housing period, when G-farm sows were fed ad libitum. Sows were grouped in the breeding section and kept grouped on deep litter in the dry sow section on all farms. Individual health examinations were performed at the time of weaning (±4 days) on 179 G-farm sows and on 167 C-farm sows. Teat- and udder skin wounds occurred less frequently (p<0.001) in G-farm sows than in C-farm sows. In addition, preweaning atrophy of all mammary glands occurred in 6.6% of the G-farm-sows but not in a single C-farm sow (p<0.001). This indicates that sow-piglet interactions decrease when sows are group housed. However, these differences did not occur in primiparous sows, suggesting that the relation between the primiparous sow and her litter is not affected. Mastitis frequency was the same in the 2 systems. Moreover, the frequency of locomotor disorders was the same in the 2 groups, and hoof overgrowth was common in both systems. These similarities could be due to the fact that all farms group housed dry sows on deep litter. A strong relation (p<0.001) between hoof overgrowth and locomotor disorders was evident. Low access to food due to low rank among primiparous group-housed sows was indicated by a lower (p<0.05) backfat thickness compared with multiparous sows, and a higher (p<0.001) frequency of skin wounds compared with individually housed primiparous sows.  相似文献   

低温胁迫下番石榴叶片生理生化变化的探讨   总被引：3，自引：0，他引：3  

刘大林 《林业科学》2003,(Z1)

通过不同低温对台湾引进的珍珠番石榴、无籽番石榴及福建省乡土番石榴的处理 ,测定其在低温胁迫下叶片若干生理生化变化 ,以探求番石榴不同品种的抗寒性与忍受的临界低温。结果表明 ,番石榴忍受的临界低温为 -3～ -4℃ ,因品种和低温持续时间而异。番石榴不同品种间耐寒性差异与叶片束缚水 自由水比值以及可溶性蛋白质、可溶性糖含量相关。乡土番石榴的抗寒性高于从台湾引进的两个品种。  相似文献   

An attempt to prevent acute toxoplasmosis in macropods by vaccination with Hammondia hammondi     

GL REDDACLIFF  SJ PARKER  JP DUBEY  PJ NICHOLLS  AM JOHNSON  DW COOPER 《Australian veterinary journal》1993,70(1):33-35

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Ovarian Activity at Naturally Attained Oestrus in the Sow. An Ultrasonographic and LH Study     

A. M. Dalin  T. Nanda  F. Hultn  S. Einarsson 《Acta veterinaria Scandinavica》1995,36(3):377

In 6 multiparous crossbred sows (2nd to 4th parity, Swedish Landrace x Swedish Yorkshire), 15 proosestrous-oestrous periods during 2 oestrous cycles were studied after weaning. The animals were controlled for oestrus, and the follicular growth and ovulation in their ovaries were followed by transrectal ultrasonography. Blood was sampled through indwelling catheters for analyses of LH and progesterone (P₄).The duration of oestrus (standing reflex) was 47 ± 12.4 h, and the interval from onset of standing reflex until the end of ovulation was 39 ± 12.4 h (range 20-64 h). The LH peak concentration was 3.7 ± 0.8 μg/1, and the interval from LH peak level until ovulation was 23 ± 8.4 h (range 8-32 h). The onset of standing reflex occurred in average 13 h before the LH peak level (range -4 - +36 h).The peripheral plasma concentration of P₄ showed a normal cyclic pattern in all animals. Low levels (mean levels, 1.1-1.3 nmol/1) were seen during prooestrus and oestrus, high mean levels were found on days 10-16 (45-75 nmol/1) in the oestrous cycle. It was concluded that for an accurate determination of ovulation, each animal has to be examined repeatedly. Ultrasonography is a most valuable tool for this purpose.  相似文献   

川南柑桔叶溃疡病的发生规律     

赖传雅  李隆华  黄治远  邓大林  范世澳 《植物病理学报》1984,14(3):152

 本病在四川省只是局部甜橙产区发生,为了查明病害在川南地区的发生规律,为防治本病提供理论依据,我们于1972~1974年每年在富顺县怀德镇蔬菜社果园选定7~9年生实生甜橙20株共400枝新梢,观察春、夏、秋梢自抽芽到老熟的叶溃疡发病规律。  相似文献