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1.
The effects of incubation temperature (+20°C vs +35°C) and media type on the ATP content and motility of spermatozoa were determined in fresh bovine semen in order to develop a method for assaying post-thaw quality. Semen was obtained from 3 bulls at 2 occasions. The spermatozoa were washed using a Ficoll-containing medium before being resuspended in each of 4 different media (I. 0.9 % NaCl; II. Trisbuffer solution; III. seminal plasma; IV. seminal plasma + Tris-buffer solution) and incubated for 6 h. The least-squares means for ATP content were higher (p ≤ 0.05) at +20°C than +35°C for all media except no. I. By contrast, the least-squares means for sperm motility were higher (p ≤ 0.05) at +35°C than at +20°C in media II and III. A decrease over time in ATP content and motility at both temperatures was also observed. The single most important factor responsible for changes in ATP content and sperm motility was the temperature and the medium, respectively.  相似文献   

2.
Control of sperm quality after commercial freezing/thawing of bull semen is still restricted to the subjective assessment of sperm motility, despite its low correlation to fertility (Söderquist et al. 1991, Kjaestad et al. 1993). Although no single in vitro method has yet been designed to predict the fertilizing ability of a given semen sample, the quantitation of viable spermatozoa (with intact plasma and acrosome membranes, and metabolically active) seems to be most promising (Woelders et al. 1991). The present report describes the use of a bioluminiscence technique to determine ATP-levels and a novel supravital stain (using fluorescent dyes) to assess the amount of viable spermatozoa in frozen/thawed semen from 3 A.I. dairy bulls with significantly different motility after thawing.  相似文献   

3.
4.
The onset of post partum ovarian activity, the number of artificial inseminations (AI) and the time of conception were monitored in 412 Icelandic dairy cows during a period of 3 years. Blood was sampled from the animals at various times after calving and the serum concentration of glucoce, urea, calcium (Ca) and magnesium (Mg) measured. A significant positive correlation was found between the levels of glucose, urea and Ca and the number of days from calving. A significant negative correlation was found between the level of urea and the time of first post partum ovulation. A significant positive correlation was found between the level of glucose and the time of conception. No correlation was found between the blood parameters and the number of AI per animal, the length of first post partum ovarian cycle or the ammount of progesterone found during that cycle. A distinct, although not statistically significant, tendency towards a negative correlation between the level of glucose and the time of first post partum ovulation was found. Our results show that the levels of glucose and urea shortly after parturition do indicate the time of onset of post partum ovarian cyclicity. Our findings indicate that low blood glucose and urea values early post partum lead to subclinical or clinical ketosis which can considerably delay the onset of ovarian activity.  相似文献   

5.
Dairy bulls, 322 Ayrshires (Ay) and 85 Friesians (Fr), were studied at the age of 11 months. Of the bulls, 286 Ay-bulls and 80 Fr-bulls produced semen of acceptable quality for use in A.I. Scrotal circumference, tonometer measure, scrotal fold thickness, 1-year body weight and testicular palpation were used to predict unsuitable bulls for A.I. Non-return rate was used as a measure of fertility. Scrotal fold thickness and 1-year weight had no significant correlation with fertility or semen quality. Scrotal circumference had a significant positive correlation with fertility. Tonometer ratio had a significant negative correlation with fertility. Testicular palpation was the best basis for predicting bulls with poor semen quality in this study. Twelve bulls were recorded as having testicles of different sizes, 1 testicle being more than 20 % bigger than the other. Only 2 of these 12 bulls produced semen of acceptable quality. One of these 2 bulls was, after slaughter, diagnosed as having a hereditary testicle disease. Friesians were shown to have significantly higher fertility than Ayrshires.  相似文献   

6.
Detailed semen evaluations were carried out on approximately 363 Santa Gertrudis, 5/8 Brahman and Brahman bulls on 12 different properties across northern Australia, as part of systematic breeding soundness examinations. A subset of bulls (n=245) were subsequently mated in groups, to cows and heifers at bull:female ratios of 2.5-6.0%, with the paternity of resulting calves being determined by microsatellite DNA testing. Motility traits of semen and spermatozoa were moderately repeatable and correlated with each other, but were unrelated to calf output. The percentage of morphologically normal spermatozoa in ejaculates was moderately to highly repeatable (e.g. r=0.10-0.64). The most common morphological abnormalities seen were mid-piece abnormalities, in particular, distal mid-piece reflex associated with a cytoplasmic droplet. Semen quality, particularly percent normal spermatozoa, was consistently related to calf output. In general, bulls with <50% normal spermatozoa sired few calves while bulls with the highest calf outputs had >70% normal spermatozoa. The presence or absence of heparin binding proteins in semen did not influence calf output. Semen from 93% of tested bulls was positive for heparin binding proteins. These results confirm that examination of semen, in particular, evaluation of percent morphologically normal spermatozoa, should be included in the breeding soundness examination of bulls.  相似文献   

7.
Ninety ejaculates from a total of 76 AI boars were extended in Beltsville Thawing Solution (BTS). Boar identity, breed, weight of the ejaculate and sperm concentration were registered. Motility and acrosome integrity were assessed after storage at 16–18°C for 6, 30, 54, 78, and 102 h. Storage time had a significant influence on both motility (p < 0.01) and acrosome integrity (p < 0.001). The Least Square Means for percentage of motility showed a small decline from 79.8% after 6 h of storage to 78.4% at 102 h. Motility at 78 and 102 h was significantly different from motility at 6 h (p < 0.05). The percentage of sperm cells with normal acrosomes declined throughout the experiment. The Least Square Means for 6, 30, 54, 78, and 102 h of storage were 93.9%, 90.6%, 88.0%, 84.8%, and 78.2%, respectively. The decrease in acrosome integrity from one storage time to the next was highly significant throughout the trial (p < 0.001). There was a significant influence of boar (p < 0.001) and sperm concentration (p < 0.01) on motility, while acrosome integrity was affected only by boar (p < 0.001). Breed of the boars and weight of the ejaculate did not influence the dependent variables.  相似文献   

8.
Iodine 131 is among the biologically most important fission products. 131I decays with a half life of 8.05 days. The metabolism of 131I and especially its secretion into cow’s milk has been widely studied.  相似文献   

9.
A midpiece sperm defect with a frequency of 25-35% in ejaculates obtained from a Hereford bull with a 60 d non-retum rate of 76.4% after careful pre- and postfreeze semen selection was studied in light microscope and by transmission electron microscopy. The defect consisted in a folding and coiling of the distal midpiece characterized by disorganization and irregularity of mitochondria surrounding the axial fiber bundle, combined with retraction of doublet fibers and dislocation and fracturing of these elements and the corresponding dense fibers. Based on examination of the sper- matogenic epithelium it was concluded that the alterations in the axial fiber bundle were secondary to those in the mitochondrial sheath. The abnormality appeared to be related to the “Dag-like” defect earlier observed in different breeds.  相似文献   

10.
Diluted bull semen samples were bombarded with a 24 Mev proton beam. Dose response curves for the fraction of cells which survived the bombardment and for the average velocity of the surviving cells were measured. Target theory indicated a cross section of the sensitive volume of 2.1 × 10-10 cm2. Respiration measurements showed that the oxidative phosphorylation in the sperm remained coupled after the bombardments. The efficiency with which free energy from ATP hydrolysis was converted into mechanical work by the sperm was found to decrease after proton bombardment. The half-value dose for this effect was two and a half times higher than the half-value dose for motility damage. These respiration measurements indicate that the damage due to the bombardment is not to the metabolic system or to the contractile system in the sperm flagellum, but to a control system for the motility. The results of the target theory shows that this control system is localized in a small element of approximately 1600 A diameter. The centriole is tentatively proposed as being this control element.  相似文献   

11.
小麦旗叶Rubisco周转与籽粒含氮量的关系   总被引:3,自引:0,他引:3  
随着旗叶的衰老,Rubisco含量逐渐减少.延缓小麦旗叶的衰老进程(抽穗期施氮肥),可增加旗叶Rubisco的含量,提高籽粒的全氮含量.在小麦旗叶全展后28d内,Rubisco的15N丰度处于较高水平,表明仍有Rubisco的重新合成;而在28d以后,Rubisco的15N丰度处于低水平,表明无Rubisco的重新合成.但这时籽粒的15N丰度却上升.旗叶全展后14d内Rubisco的15N丰度高于旗叶中全氮的丰度,说明此时期Rubisco重新合成的速率高于其它蛋白质;旗叶衰老过程中Rubisco的15N丰度的净转移高于全氮,Rubi-sco净N转移也高于全氮,表明Rubisco向籽粒中转移的氮素多于其它蛋白质,对籽粒含氮量的影响最大.  相似文献   

12.
应用半薄切片法、高效液相色谱法(HPLC)和荧光显微镜研究了6种芦荟叶的结构、芦荟素的含量和储藏芦荟素的组织.结果表明,6种芦荟叶均由表皮、光合组织、储水组织和维管束组成,都表现出明显的旱生植物肉质叶的结构特征,表皮由一层扁平的细胞组成,其外壁加厚,并覆盖着厚的角质膜,气孔器凹陷,储水组织发达.6 种芦荟叶的结构存在显著差异.木立芦荟(Aloe arborescens Mill.)和易变芦荟(A. mutabilis Pillans)的光合组织细胞呈长柱状,类似栅栏薄壁组织.中华芦荟(A. vera L. var. chinensis Berg.)、库拉索芦荟(A. vera L.)、皂叶芦荟(A. saponaria Hawer)和绿芦荟(A. greenii Bak.)则为等直径薄壁细胞.木立芦荟、中华芦荟、易变芦荟和库拉索芦荟的维管束中有大型薄壁细胞,皂叶芦荟和绿芦荟的维管束中无大型薄壁细胞.木立芦荟、易变芦荟和库拉索芦荟在光合组织和储水组织之间有一层不含叶绿体的小型薄壁细胞,包围着储水薄壁组织,称之为储水组织鞘.中华芦荟、皂叶芦荟和绿芦荟则没有储水组织鞘.HPLC测量结果表明,木立芦荟叶芦荟素含量最高,库拉索芦荟和易变芦荟次之,中华芦荟、皂叶芦荟和绿芦荟含量最低.荧光显微镜观察结果表明,在紫外光和蓝光下,黄色和黄绿色小球体仅存在于维管束的大型薄壁细胞、维管束鞘和储水组织鞘中,而光合组织和储水组织中没有黄色和黄绿色小球体.因此,维管束中大型薄壁细胞、维管束鞘和储水组织鞘是芦荟素等蒽醌类物质的储藏场所.综上所述,芦荟素含量与维管束的大型薄壁细胞、维管束鞘和储水组织鞘的情况密切相关.  相似文献   

13.
六种芦荟叶的解剖结构及其与芦荟素含量的相关性   总被引:10,自引:0,他引:10  
应用半薄切片法、高效液相色谱法(HPLC)和荧光显微镜研究了6种芦荟叶的结构、芦荟素的含量和储藏芦荟素的组织。结果表明,6种芦荟叶均由表皮、光合组织、储水组织和维管束组成,都表现出明显的旱生植物肉质叶的结构特征,表皮由一层扁平的细胞组成,其外壁加厚,并覆盖着厚的角质膜,气孔器凹陷,储水组织发达。6种芦荟叶的结构存在显著差异。木立芦荟(Aloe arborescens Mill.)和易变芦荟(A.mutabilis Pillans)的光合组织细胞呈长柱状,类似栅栏薄壁组织。中华芦荟(A.vera L.var.chinensis Berg.)、库拉索芦荟(A.vera L.)、皂叶芦荟(A.saponaria Hawer)和绿芦荟(A.greenii Bak.)则为等直径薄壁细胞。木立芦荟、中华芦荟、易变芦荟和库拉索芦荟的维管束中有大型薄壁细胞,皂叶芦荟和绿芦荟的维管束中无大型薄壁细胞。木立芦荟、易变芦荟和库拉索芦荟在光合组织和储水组织之间有一层不含叶绿体的小型薄壁细胞,包围着储水薄壁组织,称之为储水组织鞘。中华芦荟、皂叶芦荟和绿芦荟则没有储水组织鞘。HPLC测量结果表明,木立芦荟叶芦荟素含量最高,库拉索芦荟和易变芦荟次之,中华芦荟、皂叶芦荟和绿芦荟含量最低。荧光显微镜观察结果表明,在紫外光和蓝光下,黄色和黄绿色小球体仅存在于维管束的大型薄壁细胞、维管束鞘和储水组织鞘中,而光合组织和储水组织中没有黄色和黄绿色小球体。因此,维管束中大型薄壁细胞、维管束鞘和储水组织鞘是芦荟素等蒽醌类物质的储藏场所。综上所述,芦荟素含量与维管束的大型薄壁细胞、维管束鞘和储水组织鞘的情况密切相关。  相似文献   

14.
To investigate the security of semen biologically, 15 bull semen samples were collected (of which 5 exhibited clinical signs of Foot-and-mouth disease) and identified by RT-PCR and virus isolation. The results indicated that the semen of the infected bulls were contaminated by Foot-and-mouth disease virus (FMDV), but FMDV was not detected in semen samples from those bulls not showing clinical signs of Foot-and-mouth disease (FMD). This is the first report of the presence of FMDV in bull semen due to natural infection in China. The analysis of the partial sequence of the VP1 gene showed that the virus strain isolated from semen has 97.9% identity with the virus isolated from vesicular liquid of infected bulls showing typical signs of FMD and belonged to the same gene sub-group.  相似文献   

15.
西部地区主要猪种和野猪H-FABP基因分子标记   总被引:12,自引:0,他引:12  
庞卫军  孙世铎  李影  陈国柱  杨公社 《遗传》2005,27(3):351-356
利用PCR-RFLP(Hinf I、Hae Ⅲ和Msp I 3种限制性内切酶)分子标记技术,检测了杜洛克猪、长白猪、大白猪、内江猪、荣昌猪、汉江黑猪、汉中白猪、八眉猪和野猪共计265头猪H-FABP基因5′-上游区和第二内含子区的遗传变异,并利用最小二乘模型分析了H-FABP基因对猪肌内脂肪含量的遗传效应。结果表明:(1)在Hinf I-RFLP位点上,上述品种和野猪均存在多态性,其中大白猪、八眉猪、汉江黑猪、汉中白猪和野猪表现为低度多态,杜洛克、长白猪、内江猪和荣昌猪为中度多态;除汉江黑猪(P<0.05)和野猪(P<0.01)外,其他猪种基因频率和基因型频率都处于Hardy-Weinderg平衡状态(P>0.05);而在Hae Ⅲ-RFLP和Msp I-RFLP位点上,仅内江猪、荣昌猪、汉江黑猪和八眉猪为单态;(2)9种基因型对肌内脂肪(IMF)含量的影响,HH>Hh>hh,DD相似文献   

16.
In grape must of high sugar concentration, yeast growth, the viability rate of “resting” yeast cells, and fermentation activity were stimulated under certain conditions of aeration and temperature. This stimulation might be interpreted as being a result of the yeast cell sterol content. The addition of certain sterols to the fermenting medium was able to increase this sterol content. According to aeration conditions of the medium, which determined the sterol content of yeasts, the sterols added in the medium acted as (i) growth factors, (ii) fermentation inhibitors, and (iii) survival factors for the yeast.  相似文献   

17.
土壤含水量与头季稻和再生稻产量的关系   总被引:2,自引:0,他引:2  
土壤含水量与头季稻和再生稻产量的关系熊洪SombatChinawong(四川省农科院水稻高粱所,泸州646100)(KasetsartUniversity,Bangkok73140)RelationshipBetweenSoilWaterConten...  相似文献   

18.
Conidia ofMetarhizium flavoviridewere hermetically stored at50 °C and 14 moisture contents between 2.5 and 31.8% (freshweight basis) for up to 146 d, and tested for germination onSabouraud Dextrose Agar at 25 °C for 24 h. Survival of conidiaconformed to cumulative negative normal distributions and all14 survival curves could be constrained to a common origin.There was a negative logarithmic relation between longevityand conidia moisture content, but limits to the relation weredetected: the lower-moisture-content limit was 4.6% [in equilibriumwith 10.7% relative humidity (RH) at 20 °C], below whichvalue further reduction in moisture content did not increaseconidia longevity; and an upper-moisture-content limit betweenabout 21.2 and 31.8% moisture content (between 77 and 90.0%equilibrium RH at 20 °C) above which conidia longevity nolonger decreased. The observations could also be described bya negative semi-logarithmic relation between conidia longevityand equilibrium relative humidity. In this model, each reductionin equilibrium relative humidity by 11.2% within the range 10.7to 80% RH doubled conidia longevity. The similarities in theserelations, and the limits to these relations, between the conidiaof this entomopathogenic fungus and the orthodox seeds of higherplants are discussed.Copyright 1998 Annals of Botany Company Conidia longevity, equilibrium relative humidity,Metarhizium flavoviride, moisture content, hermetic storage, viability equation  相似文献   

19.
应用三个种子含锌量不同的小麦品系为实验材料,研究了在缺锌和供锌条件下锌在小麦幼苗中的分配规律。实验证明在缺锌的条件下,小麦幼苗植株含锌量与种子的含锌量成正相关。锌在三个品系小麦不同叶位中的分配规律是一致的,但种子含锌量低的小麦向幼叶中分配的锌量比例大。在供锌的条件下,种子含锌量高的品系地上部的总锌量比低锌品系高。  相似文献   

20.
The increase in ATP and E.C. in the mung bean axes during imbibi- tion was accompanied by an increase in the rate of protein synthesis. When the axes were treated with 5×l0-5 M, and 5×10-4M 2,4-Dinitrophenol at the first 4 hours of imbibition respectively, the production of ATP was inhibited, and the E.C. value decreased; at the same time, the incorporation of 3H-leucine into the trichloroacetic acidinsoluble protein was inhibited also. CCCP (1×10-5M and 1×10-4M) had a similar effect as DNP on mung bean axes. Incubated with 0.2 μg. ml-1 cycloheximide for 4 hours, the protein synthsized reduced by 69% compared to the control, the ATP and E. C. were slightly higher than the untreated one; while incubated with 1 μg and 5 μg cycloheximide, the protein synthesis almost stopped, the content of ATP decreased slightly, and E. C. value remained constant. When the mung bean axes were incubated with 1 μg, and 10 μg. ml-1 of actinomycin D for 4 hours, the protein synthesis was inhibited 23%, and 48% respectively. On the other hand, ATP, E. C. and the adenylate pool were not affected. These results showed that protein synthesis in mung bean axes during im- bibition was highly sensitive to the changes of ATP level and E. C. value. In contrast, adenylate pool was not affected by the actinomycin D.  相似文献   

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