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1.
沼泽型水牛发情周期卵泡发育波的发育动态观察   总被引:1,自引:0,他引:1  
用B-型超声波观察9头沼泽型母水牛的卵泡发育动态,发现沼泽型母水牛的发情周期由2个或3个卵泡发育波(简称卵泡波)组成,以2个卵泡波为主。在2个卵泡波的母水牛中,波的长度为19.29d,青年牛第1、2波分别在发情周期的第1.25、9.75天出现,第1、2波征集、选择的卵泡数分别为6.25、3.25和5.725、3.5个;经产牛第1、2波分别在第1.0、第12.33天出现,其征集、选择的卵泡数分别为8.0、4.67和6.67、4.33个。3个卵泡波的母水牛,波的长度为23.5d,3个波分别在发情周期的第1.5、8.0和15.5天出现,征集、选择的卵泡数分别为11.0、4.0,12.5、4.5和12.0、5.5个。以上这些数据之间同类比较均无显著性差异(P>0.05)。左右卵巢上各类卵泡数量统计无显著差异(P>0.05),排卵优势卵泡出现在左卵巢的机率较大,占77.8%,青年牛发情后48h排卵多达66.7%,经产牛在24h内排卵较多。  相似文献   

2.
运用B超跟踪观察经同期发情处理后的沼泽型水牛的卵泡发育动态,并应用放射免疫测定法(RIA)测定其发情周期中血清促卵泡素(FSH)、促黄体素(LH)、雌二醇(E2)、孕酮(P4)等生殖激素的含量,分析了沼泽型水牛的卵泡波情况,并比较了四种生殖激素在发情周期不同时间段及不同卵泡波类型之间的差异性。发现沼泽型水牛的发情周期由2个或3个卵泡波组成,以2个卵泡波为主;2个或3个卵泡波中各个波征集、选择的卵泡数之间无显著差异;血清FSH、LH、E2、P4水平在表现为不同卵泡波类型的青年水牛无显著差异(P>0.05)。  相似文献   

3.
不同卵泡波类型水牛生殖激素变化的试验研究   总被引:1,自引:1,他引:0  
为了了解不同卵泡波类型水牛的生殖激素变化情况与卵泡波之间的关系,试验对已探明卵泡波类型的6头沼泽型水牛采集经同期发情处理后的血样,采用放射免疫测定法(RIA)测定其血清生殖激素浓度,分析比较不同卵泡波类型水牛的生殖激素变化情况。结果发现3个卵泡波青年水牛的促卵泡素(FSH)水平在发情周期第15 d后明显高于表现为2个卵泡波的青年水牛(P<0.05);黄体素(LH)水平则相反,在第15 d前,2波周期的青年水牛其黄体素(LH)水平明显高于3波周期的青年水牛。3波周期的青年水牛,其E2、P4水平要高于2波周期的青年水牛。血清促卵泡素(FSH)、黄体素(LH)、雌二醇(E2)、孕酮(P4)水平在表现为不同卵泡波类型的水牛中并不存在显著差异(P>0.05)。  相似文献   

4.
为了探讨免疫抑制素对水牛超排的作用,进一步揭示水牛超排机理,选取17头具有正常发情周期的母水牛,随机分为试验组(10头),对照组(7头),试验组首次免疫重组猪抑制素亚基融合蛋白1 mg/头,首免后第28和第56天分别进行加强免疫,剂量为0.5 mg/头,对照组牛同期注射矿物油与生理盐水混合佐剂。试验组牛在首免、二免和三免当天分别用B超仪进行卵泡大小监测和计数,在超排后第6天用B超仪进行卵泡和黄体数进行统计。用免疫抑制素组水牛平均卵泡数在加强免疫后,卵泡数量从8.8增加到15.0个,但与对照组相比差异不显著(P>0.05)。超排后,试验组的平均成熟卵泡数、黄体数和排卵率分别是12.2±0.79,9.0±1.06和73.77%,与对照组相比差异显著。胚胎回收总数和可用胚胎数差异不显著。结果表明,利用免疫抑制素免疫水牛,可提高水牛的超排效果。  相似文献   

5.
试验对水牛发情周期血清和唾液中雌二醇(E_2)和孕酮(P_4)的浓度变化规律、水牛唾液结晶与卵泡发育变化分别进行了分析研究,为进一步探讨水牛发情规律、指导生产提供依据。采用酶联免疫分析法(ELISA)测定发情母水牛血清和唾液中E_2和P_4的浓度变化,并对血清和唾液的激素变化规律进行相关性分析。结果表明,水牛血清和唾液中的E_2和P_4呈波动性变化。发情前期,唾液中P_4浓度一直维持在6.50~7.10 ng/mL,发情第13天达到11.09 ng/mL,随后快速下降。唾液中E_2浓度在发情第3~5天出现一个峰值178.53 pg/mL,在第14~17天唾液中E_2浓度显著升高,出现第二个峰值179.10 pg/mL。母水牛唾液中E_2和P_4浓度的变化趋势与其在血清中的变化趋势基本一致,均呈显著相关(P<0.05);唾液中E_2与P_4浓度呈极显著相关(P<0.01)。水牛发情当天唾液结晶呈现明显的蕨类作物形状且分维值显著低于其他时间点(P<0.05)。水牛发情周期唾液结晶图形的变化与卵巢卵泡发育基本同步,可作为监测水牛发情及预测排卵的可靠指标之一。  相似文献   

6.
选择从澳大利亚购进的2岁左右发情周期为21天的育成母牛10头,用放射免疫测定法(RIA)测定发情周期血清中孕酮(P_4)和17β-雌二醇(E_2)的浓度,用B-型超声波诊断仪检测发情周期卵巢卵泡发育变化,结果显示:E_2浓度在奶牛发情周期中主要表现出两个波峰,只是其中一个波峰较小,这与卵泡两个发育波态势相似,而P_4在发情周期中却只表现出一个波峰,与卵泡两个发育波部分相似。  相似文献   

7.
水牛活体采卵及体外受精研究   总被引:8,自引:0,他引:8  
应用B型超声波采卵法进行水牛活体采卵,42头3~17岁良种水牛间隔3 d采卵1次,连续采卵2~3次,共进行96次,穿刺卵泡762个,回收卵母细胞513枚,其中可用卵母细胞305枚,回收率67.3%,可用卵占回收卵总数59.5%,平均每头次获卵母细胞5.34±4.25枚,其中可用卵母细胞3.18±2.89枚.采集的可用卵母细胞以MC和SOF 2种系统培养,受精分裂率和囊胚率分别为45.2%、30.6%和70.8%、18.8%.用8枚胚胎移植受体母牛8头,妊娠2头,产下了世界第1例由沼泽型水牛孕育生产的河流型水牛.  相似文献   

8.
中国水牛 2 ,2 66 5万头 ,居世界前三位 ,属于沼泽型水牛。为了使水牛由役用转向乳、肉、役多用途发展 ,采用河流型的尼里 -拉菲、摩拉水牛与沼泽型水牛进行二个品种级进杂交方法或三个品种育成杂交方法。试验证明 :经杂交二代的尼杂二代和三品杂水牛的乳用性能已达到河流型的尼里 -拉菲 (P >0 0 5 )或超过摩拉水牛(P <0 0 5 ) ,而高于沼泽型水牛一倍多 (P <0 0 1)的泌乳水平。杂交水牛将是中国水牛乳业发展中乳畜的主要来源  相似文献   

9.
选择从澳大利亚购进的2岁左右、发情周期为21天的育成母牛10头,用放射免疫测定法(RIA)测定了发情周期血清中促卵泡素(FSH)和促黄体素(LH)的浓度,用B-型超声波诊断仪检测发情周期卵巢卵泡发育变化。结果显示:FSH和LH浓度在奶牛发情周期中主要表现出两个波峰,其中一个波峰较小,这与卵泡两个发育波态势相似。  相似文献   

10.
利用微卫星DNA标记分析槟榔江水牛群体遗传特征   总被引:2,自引:0,他引:2  
槟榔江水牛是近年在我国云南西部发现的第一个本土河流型水牛.为了揭示其群体遗传多样性、群体遗传组成、其与河流型和沼泽型水牛的遗传关系及沼泽型水牛对该水牛的基因渗入等重要遗传背景信息,本研究采用30个微卫星DNA标记对141份槟榔江水牛样品和对照群体24份河流型水牛(摩拉水牛)样品、41份沼泽型水牛(滇东南水牛)样品进行了检测分析.结果,在槟榔江水牛群体中共检测到253个等位基因,其中,54个为3个群体所共享的等位基因,58个为只在槟榔江水牛与摩拉水牛间共享的等位基因,73个为只在槟榔江水牛与滇东南水牛间共享的等位基因,其余68个等位基因为该群体所独有.槟榔江水牛平均等位基因数、平均表观杂合度、平均期望杂合度和多态信息含量等参数均显著高于对照组群体,分别为8.433 3、0.640 5、0.600 9和0.594 7.该水牛群体近交系数FIS值为0.061 9.槟榔江水牛与摩拉水牛间的DA遗传距离为最小(0.114 4),在NJ树上聚为一支;而滇东南水牛与槟榔江水牛和摩拉水牛间的遗传距离较大(分别为0.382 9和0.555 3),其在NJ树上单独聚为一支.群体遗传结构分析显示,槟榔江水牛遗传组分为河流型与沼泽型2种类型水牛混合的模式(当K=2时),整个群体中有相当数量的个体存在沼泽型水牛的遗传渗入(群体中沼泽型水牛遗传组分为0.067 2).结果揭示,槟榔江水牛遗传资源独特,群体遗传多样性丰富,但该群体杂合子缺乏,且存在一定沼泽型水牛的基因渗入.  相似文献   

11.
This study characterized follicular activity and oestrous behaviour from 5 to 9 days post‐calving up to the 4th ovulation postpartum (pp) in 16 multiparous (range 2–7 parities) Thai swamp buffalo cows (Bubalus bubalis), aged 4–12 years and weighing from 432 to 676 kg. Ovarian follicular activity was examined by transrectal ultrasonography (TUS) every morning. Oestrous detection was performed twice daily by direct personal observation of behaviour and for presence of clear cervical mucus discharge and indirectly by video camera recording during 21 h/day. A follicular wave‐like pattern was present before the 1st ovulation leading to short oestrous cycles. Growth rates and maximum diameters of the ovulatory follicles did not differ between the 1st and 4th ovulations. However, growth rate for non‐ovulatory dominant follicles (DF) before the 1st ovulation was lower than for the ovulatory follicle (p < 0.05). In addition, the diameter of all ovulatory follicles (14.3 ± 0.46 mm, n = 39) was significantly larger (p < 0.01) than those of the preceding last but one non‐ovulatory DF (10.8 ± 0.20 mm, n = 5), but similar to the last preceding non‐ovulatory DF diameter (12.92 ± 0.96 mm, n = 14). Short oestrous cycles were most common between the 1st and 2nd ovulations (93.75%, 15/16 cows, 10.2 ± 0.38 days) decreasing in prevalence thereafter (50%, 3/6 buffaloes, 12.0 ± 1.53 days). Oestrous signs were relatively vague around the 1st ovulation pp to become more easily detectable thereafter. This study suggests that properly fed swamp buffaloes could be mated successfully within 2 months pp, at their 2nd spontaneous ovulation, provided oestrous detection is at least performed daily at 06:00–08:00 hour.  相似文献   

12.
The hypothesis of the present study is that active immunization of cows against inhibin would neutralize endogenous inhibin, increase circulating levels of follicle stimulating hormone, and subsequently affect follicular dynamics and the ovulation rate during the estrous cycle. Thirteen cows were immunized against inhibin alpha-subunit and, 6 cows were immunized with a placebo. Both groups were given 4 booster immunizations 7, 14, 21, and 34 weeks after the primary injection. Ovaries were examined daily after the 2nd, 3rd, and 4th booster immunizations by transrectal ultrasonography for 25 days. After the 4th booster immunization, blood samples were collected daily for one complete estrous cycle to measure FSH and LH. The results showed that the immunized cows generated antibodies against inhibin, and that they had higher FSH levels compared with the controls. The number of follicular waves during the estrous cycle was higher in the immunized cows (3 or 4 waves) than in the controls (2 or 3 waves). Moreover, the immunized cows had a greater number of follicles during the estrous cycle compared with the control cows. The maximum number of follicles was 14.8 +/- 1.7 vs 5.4 +/- 0.2 in inhibin-immunized and control cows, respectively, during the first follicular wave and 13.9 +/- 1.9 vs 5.6 +/- 0.7, respectively, during the ovulatory wave. Multiple ovulations were increased in the immunized cows. However, the ovulation rate varied greatly in the immunized animals. In conclusion, immunization against inhibin increased FSH secretions during the estrous cycle in the cows. Moreover, the immunized cows had a greater number of follicular waves during the estrous cycle and a greater number of follicles, and this could be used as a potential source of oocytes for use in IVF/embryo transfer programs.  相似文献   

13.
The aim of the present study was to test the hypothesis of wave pattern of follicular growth and to monitor the ovarian follicular dynamic in Iraqi buffalo cows. Reproductive tracts were collected at random intervals slaughtered at Mosul abattoir. According to morphological appearance of the corpus luteum, the estrous cycle was divided into four stages. The number of subordinate follicle (<5 mm in diameter) was higher during stage 1 (metestrous) and stage (proestrous and estrous) than during other stages of the estrous cycles, 13.5 ± 6.08 and 4 9.41 ± 3.94, respectively. There were fewer follicles (5–8 mm in diameter) during early diestrous and proestrous, 1.66 ± 1.42 and estrous, 0.69 ± 0.47 than during metestrous, 4.53 ± 3.23 and late diestrous, 3.66 ± 2.23. Follicles > 8–12 mm in diameter were more numerous during early diestrous, 1.62 ± 1.29 and late diestrous, 1.03 ± 0.72. A total 38 (64.6%; 82/127) animals examined showed follicles larger than 8 mm during early and late diestrous (stage 2 and stage 3). This indicated that these buffaloes developed two follicular waves in their cycle. Buffaloes did not show follicles larger than 8 mm during early and late diestrous were 45 animals (35.4%; 45/127), but all of these presented one large follicle during the following stage. These buffaloes develop only one follicular wave in their cycle. It could be concluded that, 64.6% of Iraqi buffalo cows develop two patterns of follicular waves, and 35.4% showed one wave of follicular dynamics.  相似文献   

14.
Follicular and hormonal dynamics during the estrous cycle in goats   总被引:3,自引:0,他引:3  
Transrectal ultrasonography of ovaries was performed daily in 6 goats for 3 consecutive estrous cycles. Blood samples collected daily were measured for concentrations of FSH, inhibin A, and estradiol-17beta. Follicular and hormonal data were analyzed for associations between the follicular waves and hormonal concentrations. During the interovulatory intervals, follicular growth and regression occurred in a wave like pattern (2-5 waves), and the predominant patterns were three and four follicular waves. In addition, there was no significant difference among the diameters of dominant follicles during the growth phase of the follicular waves. The number of 3 mm follicles peaked on days 0, 7, and 11 in interovulatory intervals that had three follicular waves and on days -1, 5, 11, and 15 in those that had four follicular waves. Plasma concentrations of FSH increased around the day of follicular wave emergence and declined with the growth of follicles. Circulating FSH increased again concomitant with regression of dominant follicles in the anovulatory wave, whereas FSH levels remained low in the ovulatory wave. Inhibin A was negatively correlated with FSH, while it was positively correlated with estradiol-17beta, suggesting that inhibin A is a product of healthy growing follicles and that it contributes to the suppression of FSH secretion. In conclusion, the growth of ovarian follicles in goats exhibits a wave-like pattern, and follicular dominance is less apparent in goats. Moreover, inhibin A may be a key hormone for regulation of the follicular wave through suppression of FSH secretion in goats.  相似文献   

15.
The well-documented phenomenon of reduced conception rate in dairy cows during the hot season involves impaired functioning of the ovarian follicles and their enclosed oocytes. Three experiments were performed to examine the administration of low doses of follicle-stimulating hormone (FSH) to induce turnover of follicles that are damaged upon summer thermal stress and to examine whether this FSH administration has beneficial effects on preovulatory follicles. In experiment 1, synchronized heifers were treated with 100 mg of Folltropin-V (n = 7) or 4.4 mg of Ovagen (n = 6) on day 3 of the estrous cycle. Treatment with both FSH sources resulted in greater (P < 0.05) numbers of follicles than in control animals (n = 12) on day 6 of the estrous cycle, indicating that low doses of FSH can increase the number of emerging follicles in a follicular wave. In experiment 2, milking cows were assigned to a control group (n = 4) or treated with 2.2 mg (FSH-2.2; n = 6) or 4.4 mg (FSH-4.4; n = 5) Ovagen. Follicle-stimulating hormone was administrated on day 3 or 4 and day 10 or 11 of the estrous cycle, coinciding with emergence of the first and second follicular waves, respectively. The number of follicles emerging during the first wave tended to be higher (P < 0.1) in FSH-4.4-treated cows than in controls. The second-wave dominant follicles emerged 2 d later in the treated cows and were smaller in diameter (P < 0.05) than controls, 2 d before aspiration. Despite being younger, the preovulatory follicles of FSH-4.4 cows expressed a steroidogenic capacity that was similar to controls with a tendency toward greater insulin concentrations (P < 0.09). In experiment 3, milking cows were assigned to a control group (n = 6) or treated with 4.4 mg Ovagen (FSH-4.4; n = 6). Follicle-stimulating hormone was administrated on day 3 and day 12 or 13 of the estrous cycle. The number of emerging follicles was higher (P < 0.05) in the treated vs control cows. However, the features of the preovulatory follicle developed in the subsequent cycle did not differ between groups. In summary, low doses of FSH can efficiently induce follicular turnover accompanied by a modest effect on the preovulatory follicle of the treated cycle. It appears that the administration of low doses of FSH, precisely timed to synchronize with the emergence of follicular waves, might have a beneficial effect on the preovulatory follicle and its enclosed oocyte.  相似文献   

16.
Based on different surveys, dairy farmers are concerned about extensive use of exogenous oxytocin in buffaloes, which is being held responsible for reproductive problems including irregular oestrous cycle and delayed ovulation. For these concerns, effects of oxytocin injection on postpartum follicular dynamics, postpartum oestrous interval (PEI), oestrous length, the interval from onset of estrus to ovulation and blood progesterone (P4) were studied in Nili-Ravi buffaloes. For this purpose, 23 animals within 1 week after calving were randomly divided into three groups: without oxytocin (CON; n = 7), 10 i.u. oxytocin (LOW; n = 8), 30 i.u. oxytocin – (HIGH; n = 8) and used to record the PEI for the study period of 154 days. At subsequent estrus, three buffaloes from each group (not served) were selected randomly to monitor two cycles for 6 weeks. Transrectal ultrasonography was performed to evaluate follicular and corpus luteum (CL) development, and blood sampling was done for progesterone (P4) analysis. These results revealed that postpartum oestrous interval (PEI) decreased significantly in oxytocin-treated groups. The number of small, medium and total follicles on the left ovary was significantly higher in the HIGH group. However, an overall number of small and total follicles on both right and left ovaries was significantly higher in CON and HIGH groups. On the other hand, there was no difference in the number of follicles on the right ovary among all treatment groups. The same was true for the size of pre-ovulatory follicles, CL, P4 concentrations and oestrous cycle length. The intervals from onset of estrus to ovulation and from standing estrus to ovulation were increased considerably in the HIGH group. It is concluded that exogenous oxytocin administration resulted in the shortening of PEI but triggered a delay in ovulation. Moreover, a higher dose of oxytocin could stimulate the growth of small, medium, and total follicles in postpartum Nili-Ravi buffaloes.  相似文献   

17.
Factors that affect ovarian follicular dynamics in cattle.   总被引:1,自引:0,他引:1  
Studies of ovarian follicular dynamics in cattle may lead to methods for improving fertility, for synchronizing estrus with more precision, and for enhancing superovulatory responses. Within an estrous cycle, two or three large (> 10 mm) follicles develop during consecutive waves of follicular growth. The last wave provides the ovulatory follicle, whereas preceding wave(s) provide follicles that undergo atresia. The life span of large follicles seems to depend on the pulsatile secretion of LH; decreased frequency of LH pulses results in atresia of large follicles. Aromatase activity in the walls of the largest follicles is greatest during the first 8 d of the estrous cycle and decreases by d 12. Steroidogenesis of the largest and second-largest ovarian follicles differs on d 5, 8, and 12 of the estrous cycle. Follicular dynamics are altered by negative energy balance and lactation. The number of large follicles and concentration of estradiol during the preovulatory period differs between postpartum lactating and nonlactating cows. Dietary fats stimulate follicular growth when they are fed to increase energy balance. Administration of bovine somatotropin decreases energy balance and has a differential effect on ovarian follicular responses; growth of the largest follicle does not change, but growth of the second-largest follicle is stimulated by somatotropin. Studies of follicular dynamics in lactating cows demonstrate changes in ovarian function associated with energy balance that may be related to inefficient reproductive performance of cows producing high yields of milk.  相似文献   

18.
Relatively few studies have been reported regarding the reproductive physiology of female Thai native cattle. Therefore, the objective of the present study was to evaluate the follicular dynamics and concentrations of follicle stimulating hormone (FSH), estradiol (E2) and progesterone (P4) during the estrous cycle in Thai native heifers (TNH) and to compare obtained results with those of European and Indian cattle breeds previously reported. For the detection of estrus, ovaries of all 20 heifers were examined twice daily (12 h intervals) by ultrasonography for three consecutive estrous cycles. From data of 60 estrous cycles (n = 60 estrous cycles from 20 heifers), it was found that 14 (70%) and 6 heifers (30%) had two (42 estrous cycles collected from 14 heifers) and three follicular waves (18 estrous cycles collected from 6 heifers), respectively. The days when estrus was detected, interovulatory intervals, life‐spans of corpus lutea (CL), and days for growing and regression of CLs were shorter in the two follicular waves than those in the three follicular waves (P < 0.05). In both two and thre follicular waves, larger maximum diameters and higher growth rates of the dominant follicle (DF) in an ovulatory wave were observed than those of the preceding waves without ovulation (P < 0.05). There was a progressive increase in follicular size and FSH and E2 production during follicular growth in each follicular wave. In addition, the FSH and E2 peak concentrations during the ovulatory wave were higher than those of the anovulation waves (P < 0.05). Moreover, although the ovarian follicular dynamic patterns in Thai native heifers were similar to those previously reported for European and Indian cattle breeds, the diameter of the largest preovulatory follicle (OF), subordinate follicles (SF) and CLs were smaller than those in European and Indian cattle breeds. In conclusion, when compared with European and some breeds of Indian cattle, the length of interovulatory intervals was shorter, and the sizes of dominant SF and CLs were smaller in Thai native heifers.  相似文献   

19.
Ovarian follicular dynamics of cattle were examined during the estrous cycle, early pregnancy and in response to PMSG. Number and size of follicles were monitored by ultrasonographic examinations. During the estrous cycle, distinct periods of follicular dominance (measured by the increase in difference in size between the largest and second largest follicle) occurred in both the luteal (Days 6-8) and proestrus (18-22) phases of the estrous cycle (two follicular waves). Associated with the well timed development of the first dominant follicle was a change in distribution of follicle numbers in small (less than 5 mm; increased on Days 2-4), medium (6-8 mm; increased on Days 3-5) and large (greater than or equal to 9 mm; increased on Days 6-9) follicular size classes. Follicular development was greater on the ovary bearing the CL for the period that the CL was present. The dominant follicle formed during the first follicular wave was capable of ovulating (6 of 8 heifers) following an injection of a synthetic analogue of prostaglandin F-2 alpha on Day 9 of the estrous cycle. During early pregnancy (Days 6-34), follicular development (size of largest follicle, number of follicles and total accumulated size of all follicles) on the ovary bearing the CL was suppressed between Days 24 and 34 of pregnancy. This was a local effect in that follicular development was sustained on the contralateral ovary. Therefore, the CL or conceptus may be regulating follicular development in a manner to help prevent luteolysis. Associated with the injection of PMSG was an initial increase in the number of small follicles followed by their recruitment into medium and large size classes leading to ovulation. Number of follicles greater than 5 mm on the Day of estrus was related (r = .97) to the number of subsequent embryos and oocytes collected. Ultrasonography is a valuable technique to monitor ovarian follicular dynamics in cattle, and can thereby be used to infer changes in physiological and endocrine states.  相似文献   

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