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奶牛新鲜和冷冻胚胎分割移植试验 总被引：3，自引：0，他引：3
用简单方法,分割7～8日龄新鲜牛胚胎(1分为2),裸半胚成对移植给66头受体,90天妊检,移植妊娠率为56.1％(37/66)。除6头流产和尚有5头待产外,已有26头受体产犊35头,其中有9对同卵双胎,双胎率为34.6％(9/26),半胚产犊率为29.2％(35/120)。对影响成对半胚移植妊娠率和半胚产犊率的诸多因素如胚胎质量,胚胎在体外停留时间、胚胎发育阶段、受体牛品种、黄体状况等进行了较系统的研究。同时对冷冻胚胎进行了分割试验,移植妊娠率为45.5％(5/11),已产3头犊牛。对快速冷冻和常规冷冻胚胎分割后的移植妊娠率进行了比较,分别为25.0％(1/4)和57.4％(4/7)。 相似文献
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用简易分割方法,分割奶牛冷冻胚胎16枚,获得半胚32枚,分割成功率为100％(16/16),可移植半胚29枚,移植于16头受体牛,到第3个情期未返情者经直肠检查有6头妊娠,妊娠率为37.5％(6/16)。其中,在分割前或者分割后经恢复培养0.5～2h再移植的10头受体牛,5头妊娠;而未经恢复培养,分割后直接移植的6头受体牛中,只有1头妊娠。移植后3个月,直肠检查确定2头流产。已有1头受体黄牛生出1头奶牛牛犊(母)和1头受体奶牛产1头奶牛牛犊。其余的2头妊娠受体牛将于9月份产犊。此外,用简易分割法分割奶牛胚胎5枚,得到半胚10枚,裸半胚直接冷冻,解冻后回收可移植半胚5枚,移植于4头受体牛,无一头妊娠。结果表明,冷冻胚胎的分割半胚优于分割后冷冻半胚移植效果;冷冻胚胎分割前或者分割后恢复培养移植优于未经恢复培养而直接移植;简易分割法可应用于冷冻胚胎的分割。 相似文献
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用便携式分割仪在现场分割7日龄鲜胚。二枚半胚成对移植给172头黄牛受体．受体移植妊娠率50％(86／172），现已有68头受体产犊91头．其中23对为同卵双胎．双胎率33．8％(23／68)。对分割胚胎的移植妊娠率产犊率、妊娠期、季节、黄体状况等多种因素进行了研究和比较，结果表明差异皆不显著。 相似文献
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奶牛冷冻胚胎分割移植效果探讨 总被引：2，自引：0，他引：2
分割加拿大奶牛冷冻胚胎 ,借荷斯坦牛受体移植。共分割冷冻胚胎 1 5枚 ,分割为裸半胚 30个 ,分割成功率 1 0 0 %。移植受体 2 7头 (其中移植一对半胚的受体 3头 ) ,移植妊娠 1 4头 ,受体移植妊娠率51 .85% ,产犊 1 4头 ,半胚产犊率为 4 6 .6 7% ,按未分割的整胚计算 ,产犊率达到 93.34 % ,比整胚移植产犊率还提高 1 8.34个百分点。移植半胚生产 1头犊牛需胚胎 1 .0 7枚 ,比整胚减少 0 .2 6枚 ,降低成本1 51 0 .6 0元。说明胚胎分割是降低成本 ,扩大卵源 ,增加良种牛数量的有效方法。 相似文献
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2002-2004年,从饲养的812头奶牛群中,选择69头高产奶牛作供体进行超数排卵处理,63头供体牛共获胚胎495枚,超排成功率达91．3％(63／69),平均获胚胎7．17枚／头,可用胚胎402枚,平均可用胚胎5．82枚。其中采用加拿大生产的促卵泡素超排处理奶牛供体10头,获卵106枚,可用胚胎87枚,平均获可用胚胎8．7枚/头;采用鲜胚移植奶牛受体8l头,妊娠44头,妊娠率为54．3％,产犊28头,待产16头;采用冷冻胚胎移植黄牛受体278头,妊娠114头,妊娠率为41．0％。产犊22头,待产92头。 相似文献
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对解冻后品质优良的Ａ级囊胚进行分割，并将二分胚移植生产同卵双生犊牛。结果表明：９枚Ａ级囊胚切割成１８枚半胚，胚胎分割成功率１００％。单胚移植受体６头。妊娠２头，妊娠率３３．３％；双半胚移植６头，妊娠２头，妊娠率３３．３％。 相似文献
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N Seike M Teranishi S Yamada R Takakura Y Nagao H Kanagawa 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1989,51(6):1193-1199
A total of 132 embryos were recovered from 17 superovulated donor cows 7 d after estrus. Seventy-four embryos were selected and assigned to 2 treatment groups. The number of whole embryos that were directly transferred (Group A) and bisected (Group B) were 44 and 30 embryos, respectively. Sixty demi-embryos were produced from 30 morulae to blastocyst-stage embryos that were bisected. One hundred-three embryos, including whole and demi-embryos without zonae pellucidae, were nonsurgically transferred. Only one whole or demi-embryo was transferred to each recipients. The pregnancy rate for whole embryos (A) was 63.6% (28/44), while for demi-embryos (B) it was 74.6% (44/59). There was no significant difference between the pregnancy rates of whole embryos (A) and bisected embryos (B) transferred 7 d after estrus. Forty-three calves including the 14 sets of identical twins were obtained from 30 original embryos (143.3%) using the embryo bisection technique. 相似文献
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Techakumph M Sukavong Y Yienvisavakul V Buntaracha B Pharee S Intaramongkol S Apimeteetumrong M Intaramongkol J 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(8):849-852
To investigate the development of fresh and frozen swamp buffalo embryos after transfer to synchronized recipients, 14 fresh embryos and 28 frozen embryos, collected from Thai swamp buffalo cows of an elite herd at the Surin Breeding Center, were transferred nonsurgically to 31 synchronized recipients buffalo cows. One fresh embryo was transferred to each of 14 recipients. Twenty eight frozen embryos were transferred to 17 recipients of which 7 cows received I embryo, 9 cows received 2 embryos and 1 cow received 3 embryos. Pregnancy was diagnosed by real time B-mode ultrasonography one month after transfer and confirmed by rectal palpation one and two months later. The pregnant cows were kept under observation until calving. The results of fresh embryo transfer showed that 5/14 (35.7%) were pregnant after 30 days, 4/14 (28.6%) remained pregnant until the 3rd month and 2/14 (14.3%) calved. With the frozen embryos, only one cow which received three embryos became pregnant and remained so for 3 months although the embryo did not survive to full term. The overall pregnancy rate using frozen embryos was 5.9% (1/17). The study demonstrated the possibility of performing embryo transfer in elite buffalo herds for genetic improvement, however the use of frozen embryos needed further investigation. 相似文献
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Cattle embryos at the compact morula and blastocyst stages were bisected by two different methods. In some embryos the embryo bisection was performed outside of the zona pellucida and both halves were replaced into it. Other embryos were bisected within the zona pellucida and no pipetting of the halves was required. They were transferred to synchronized recipient cows and the pregnancy rates and twinning rates were evaluated. 相似文献
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山羊胚胎分割及同卵双生试验 总被引：10，自引：1，他引：10
选择山羊晚期桑椹胚、囊胚、孵出囊胚和孵出增大胚泡,用简化分割法二分。将19对裸半胚移植于18只受体羊,结果有12只妊娠,其中两只胚胎消失,两只流产,其余8只足月分娩,共产半胚羔11只。晚期桑椹胚、囊胚、孵出囊胚和孵出增大胚泡各组的半胚发育为羔羊的发育率分别为12.5％(1/8)、20％(2/10)、25％(3/12)和62.5％(5/8)。前三组均未获得同卵双生羔羊。在第四组,将4对裸半胚移植于4只受体,有3只妊娠,足月分娩半胚羔5只,其中两对为同卵双生。本研究证明,对称分割山羊孵出增大胚泡,不仅其半胚在体内仍可继续发育形成正常胎儿,而且不装透明带移植其裸半胚,仍能获得较高的同卵双生率。山羊孵出增大胚泡更适宜用简化分割法分割。 相似文献
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Sixty-five chromosomal preparations from bisected bovine embryos were examined and 43 embryos (66.2%) with metaphase plates were observed; however, only 25 embryos (38.5%) were sexed. Fifteen of the bisected embryos sexed by chromosomal analysis were transferred to each of the 15 recipients, and 5 recipients became pregnant. Female calves were born on December 28, 1985, August 2, 1986 and July 18, 1988. The first female calf born from a sexed-bisected embryo (December 28, 1985) was the first case in Japan. The gestation lengths and birth weights of these calves were 277, 278 and 274 days, and 42.0, 44.0 and 37.0 kg, respectively. These two calves grew within the range of the "Standard developmental growth curve of the Holstein heifer" of the Japanese Holstein Association. The milk yield from 2 sexed-bisected cows were recorded. In the first cow (Case 1), she produced 8,575 kg of milk, 5.0% fat and 9.4% solids-non-fat (SNF) per year. In the other cow (Case 2), her expected milk volume was 7,800 kg per year. Confirmation of parentage was done by blood typing, and certified by the Japanese Livestock Animal Improvement Association. 相似文献
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Experiments were conducted in 1985 and 1986 at the Eastern Ohio Resource Development Center, Belle Valley, to examine the feasibility of using embryo transfer to induce twinning and to examine the influence of twinning on traits of the cow and calf. Embryos were collected from a total of 14 superovulated Angus donors on two dates each in 1985 and 1986 and were transferred to Angus recipients. A total of 124 embryos were transferred to 79 recipients, with 43 (34.7%) calves born alive. Seven of 45 (15.6%) recipients implanted with two embryos produced twins. In no case did both halves of the 15 embryos that were split to produce identical twins and implanted in the same recipient survive to birth. Proportion of calves born alive did not differ among transfer codes 3 (nonsplit embryos from two different donors implanted in separate uterine horns of the same recipient), 6 (nonsplit embryos from one embryo flush implanted in separate uterine horns of the same recipient) and 7 (nonsplit embryos from two different donors implanted in the same uterine horn of one recipient). Surgical transfers tended to result in a higher proportion of embryos surviving to birth (.43 vs .21; P = .16) and a higher twinning rate (.29 vs .04; P = .36) than did nonsurgical transfers. Age of recipient did not influence embryo survival (P = .98) or twinning rate (P = .99). Gestation length was 5 d shorter (P less than .01) for twin calves than for singles. Singles were 9 kg heavier (P less than .01) at birth and 32 kg heavier (P less than .01) at weaning than twins. However, cows raising twins produced 108 kg (51%) more total weaning weight than did cows raising singles. 相似文献
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Production of sexed calves from frozen-thawed embryos 总被引：2，自引：0，他引：2
Three experiments have been conducted with the aim of producing calves from frozen, sexed embryos by combining embryo splitting and cytogenetic methods. In the first experiment, the efficacy of the bisection technique was assessed by transcervical transfer of 10 monozygotic pairs of half embryos to 10 synchronised heifers. Thirteen calves were produced, including four sets of identical twins. In the second experiment, one of the halves of each of eight split embryos was transferred while the other was processed for sexing by identification of the sex chromosomes. In the third experiment, one of the halves from each of 28 embryos was frozen while the other half was used for sexing. Eleven of the 16 which were sexed have been transferred with the production of three calves of the predicted sex. The overall sexing rate was 60 per cent and the calving rate following transfer of sexed embryos was 60 per cent and 23 per cent for fresh and frozen halves respectively. 相似文献
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An economic assessment of twin births in British dairy herds. 总被引：2，自引：0，他引：2
The effect of twinning on the subsequent health, production and reproductive performance of dairy cattle was studied by analysing the data derived from 19,755 calvings which occurred during three years on 37 farms. The data formed part of the database of a veterinary practice operating the DAISY dairy cow recording scheme for its dairy farmer clients. The average twinning rate was 2.5 per cent. For first calf heifers the rate was 0.9 per cent, and the rate increased with increasing parity to over 5 per cent for cows calving for their sixth and subsequent lactations. Although they produced more milk than their contemporaries, twin-bearing cows suffered an increased incidence of retained placenta and vulval discharges and their calving to conception interval was extended by 33 days. Furthermore, 35 per cent of these cows were culled compared with 21 per cent of their contemporaries. The benefit of having more calves for sale was reduced owing to 15 per cent of them being born dead. It is calculated that producing twins resulted in an average loss of income of 74 pounds/cow, a deficit of 15 per cent compared with cows having single calves. 相似文献
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W.J.A. Hanekamp 《Reproduction in domestic animals》1999,34(6):459-463
Contents
On three experimental farms 205 deep frozen Blonde d'Aquitaine embryos were transferred into Holstein dairy cows 7 days after a spontaneous heat. The aim of the study was firstly to examine the influence of recipient and embryo quality on pregnancy rate and secondly to study the calving performance of dairy cows carrying beef embryos. Recipients were divided into three groups based on the quality of the corpus luteum (unsuitable, moderately suitable and suitable) established by rectal palpation. Embryos classified as fair, good and excellent, were randomly distributed over the recipients, including those classified as being unsuitable. The overall pregnancy rate was 36% (standard deviation (SD) = 3.3), dystocia occurred in 48% of births (SD = 5.9), gestation was 297 days (SD = 1.2) and birth weight was 52 kg (SD = 2.0). No statistical differences were found in pregnancy rates and calving performance between the groups of recipients or between the classes of embryos. It is concluded that there is no justification to reject recipients on the basis of the quality of the corpus luteum. Furthermore there is no reason to reject fair embryos for transfer. Beef embryos in dairy cows resulted in much dystocia because of high birth weight, and in long gestation periods. 相似文献
On three experimental farms 205 deep frozen Blonde d'Aquitaine embryos were transferred into Holstein dairy cows 7 days after a spontaneous heat. The aim of the study was firstly to examine the influence of recipient and embryo quality on pregnancy rate and secondly to study the calving performance of dairy cows carrying beef embryos. Recipients were divided into three groups based on the quality of the corpus luteum (unsuitable, moderately suitable and suitable) established by rectal palpation. Embryos classified as fair, good and excellent, were randomly distributed over the recipients, including those classified as being unsuitable. The overall pregnancy rate was 36% (standard deviation (SD) = 3.3), dystocia occurred in 48% of births (SD = 5.9), gestation was 297 days (SD = 1.2) and birth weight was 52 kg (SD = 2.0). No statistical differences were found in pregnancy rates and calving performance between the groups of recipients or between the classes of embryos. It is concluded that there is no justification to reject recipients on the basis of the quality of the corpus luteum. Furthermore there is no reason to reject fair embryos for transfer. Beef embryos in dairy cows resulted in much dystocia because of high birth weight, and in long gestation periods. 相似文献