Uterine and vaginal insemination optimised in brushtail possums (Trichosurus vulpecula) superovulated with pregnant mare serum gonadotrophin and porcine luteinising hormone

2007 ◽  
Vol 19 (4) ◽  
pp. 521 ◽  
Author(s):  
F. C. Molinia ◽  
J. V. Myers ◽  
A. M. Glazier ◽  
J. A. Duckworth ◽  
J. C. Rodger
Keyword(s):  
Adjuvant Treatment ◽  
Artificial Insemination ◽  
Luteinising Hormone ◽  
Fertility Control ◽  
Blastocyst Stage ◽  
Trichosurus Vulpecula ◽  
Vaginal Route ◽  
New Methods ◽  
Treatment Changes ◽  
Pregnant Mare Serum Gonadotrophin

Artificial insemination of brushtail possums (Trichosurus vulpecula) is being developed as an assisted breeding model for endangered marsupials, as well as a bioassay for testing fertility control vaccines to manage overabundant populations. Procedures were optimised in animals superovulated with pregnant mare serum gonadotrophin (PMSG) and porcine luteinising hormone (pLH). Of three intervals examined, yields were maximal following uterine insemination at 27–29.5 h after pLH treatment (four eggs, two to three embryos per female). Compared with no insemination, uterine-inseminated animals ovulated 30–36 h rather than 28–34 h after pLH treatment. For the vaginal route, yields were maximal following insemination at 10–13 h after pLH treatment (six to seven eggs, four embryos per female) than at five other intervals, and when using acclimatised females during the autumn breeding season. This protocol was suitable for testing fertility control vaccines in April–June and was influenced by the housing location of animals, the presence of an active corpus luteum and PMSG batch, but not other factors (year of trial, Freund’s adjuvant treatment, changes in bodyweight, dose of PMSG kg–1). Embryos developed to the eight- to 16-cell or unilaminar blastocyst stage after uterine or vaginal insemination, respectively. With the timing of artificial insemination optimised, new methods to synchronise or induce oestrus and ovulation are required to achieve year-round testing of fertility control vaccines or birth of offspring.

Brushtail possums (Trichosurus vulpecula) in metropolitan Sydney: population biology and response to Suprelorin contraceptive implants

2013 ◽  
Vol 61 (1) ◽  
pp. 78 ◽  
Author(s):  
J. Eymann ◽  
D. W. Cooper ◽  
C. A. Herbert
Keyword(s):  
Urban Areas ◽  
Population Biology ◽  
Local Population ◽  
Fertility Control ◽  
Main Peak ◽  
Brushtail Possum ◽  
Trichosurus Vulpecula ◽  
Management Options ◽  
Contraceptive Implants ◽  
Over Time

The cohabitation of the common brushtail possum (Trichosurus vulpecula) with people in urban areas often causes conflict. Basic biological parameters are needed to evaluate potential new management options such as fertility control. This study investigated the biology of an urban brushtail possum population and the effects of Suprelorin contraceptive implants on individual females within that population. Trapping success remained constant over time, with 2.8 ± 0.2 individuals trapped per residential property. Recapture rates for males declined rapidly over time, with only 30% of males recaptured on the same property 12 months after initial capture (n = 30) and no males recaptured after 18 months (compared with female recapture rates of 58% after 18 months, n = 33). These data, combined with the preponderance of males observed within the lower age classes, suggests that male possum turnover is high within urban areas. This may be partially compensated for by the male-bias (1.8 : 1) observed in pouch young. Breeding was seasonal with the main peak of births in autumn, and a secondary smaller peak in spring. Suprelorin contraceptive treatment effectively inhibited reproduction in adult females for a minimum duration of 519 ± 7 (n = 5) and ≥700 ± 20 (n = 5) days after administration of one or two 4.7-mg implants, respectively, with no negative side-effects obvious. The concurrent collection of data on contraceptive efficacy and population-specific life-history parameters provides a unique opportunity to highlight the importance of understanding local population dynamics when evaluating the likely efficacy and implementation of fertility control programs to manage problem wildlife.

Effect of type of intravaginal progestagen on the outcome of fixed-time artificial insemination

1981 ◽  
Vol 96 (1) ◽  
pp. 243-245 ◽  
Author(s):  
P. A. Smith ◽  
M. P. Boland ◽  
I. Gordon
Keyword(s):  
Artificial Insemination ◽  
Present Experiment ◽  
Fixed Time ◽  
Field Trials ◽  
Oestrous Cycle ◽  
Conception Rates ◽  
Natural Service ◽  
Dose Levels ◽  
Pregnant Mare Serum Gonadotrophin

It is now possible to synchronize the cycle of ewes at all times of the year (Gordon, 1975). Conception rates approaching those obtained following natural service have been reported following double (Colas & Brice, 1970; Colas et al. 1973; Barlow, Pryce-Jones & Reed, 1974; Gordon, 1975) or single (Smith, Boland & Gordon, 1978) set-time inseminations. In France, synchronization of ewes' oestrous cycle is based on the use of a Cronolone pessary (Colas, 1975), while field trials conducted in Britain have used the 60 mg Medroxy progesterone acetate (MAP) sponge (Barlow et al. 1974). Robinson et al. (1967) in an evaluation of different progestagen treatments found MAP to be less predictable than Cronolone. The purpose of the present experiment therefore was to evaluate the use of a 30 mg Cronolone or a 60 mg MAP intravaginal treatment when used in conjunction with fixed-time inseminations. In addition, two dose levels of pregnant mare serum gonadotrophin (PMSG) were compared.

Development of a porcine follicle-stimulating hormone and porcine luteinizing hormone induced ovulation protocol in the seasonally anoestrus brushtail possum (Trichosurus vulpecula)

2002 ◽  
Vol 14 (8) ◽  
pp. 453 ◽  
Author(s):  
A. M. Glazier ◽  
F. C. Molinia
Keyword(s):  
Luteinizing Hormone ◽  
Single Injection ◽  
Polar Body ◽  
Follicle Stimulating Hormone ◽  
Brushtail Possum ◽  
Trichosurus Vulpecula ◽  
Cell Stage ◽  
Nuclear Maturation ◽  
Pregnant Mare Serum Gonadotrophin ◽  
Stimulating Hormone

Monovulatory brushtail possums (Trichosurus vulpecula) were stimulated with exogenous hormones during seasonal anoestrus to overcome ovarian insensitivity and induce ovulation. Seasonal ovarian insensitivity to pregnant mare serum gonadotrophin (PMSG) was overcome by a new porcine follicle-stimulating hormone/porcine luteinizing hormone (pFSH/pLH) protocol. This protocol was refined because the original treatment produced oocytes with abnormal morphology. Possums (n = 12 per group) received eight injections of pFSH of 1.5, 3.0 or 6.0 mg per injection (at 12-h intervals for 4 consecutive days). Ovulation was induced 12 h after the final pFSH injection with a 4-mg injection of pLH. Control animals were treated with the established protocol of a single injection of 15 IU of PMSG, followed 48 h later with an injection of 4 mg of pLH. All females responded to pFSH/pLH treatment, although optimal stimulation occurred in those receiving 8 × 3 mg pFSH, with 13–14�ovulations and recovery of 11–12 oocytes per female (8 × 1.5 mg pFSH: 13 ovulations, 8–9 oocytes; 8�×�6�mg pFSH: 7–8 ovulations, 4–5 oocytes). In contrast, only seven of 12 females responded to PMSG/pLH and, of those responding, only 2–3 ovulations occurred and only 1–2 oocytes per female were recovered. However, around 80% of oocytes recovered after PMSG/pLH treatment had undergone nuclear maturation (metaphase II/1st polar body) compared with around 60% of oocytes from pFSH/pLH-treated animals. In possums killed from 27 to 39 h after pLH treatment, ovulation onset was first observed from 30 h and by 31.5 h, all animals had completed ovulation. Laparoscopic artificial insemination (LAI) was performed on pFSH/pLH-treated animals to determine whether the oocytes produced were capable of fertilization. Uterine LAI performed 27.5–28.5 h after pLH treatment yielded 11/26 fertilized oocytes (up to 4-cell stage), whereas vaginal LAI performed 13–14 h after pLH treatment yielded 21/53 fertilized oocytes. A proportion of oocytes generated from the refined pFSH/pLH protocol are thus properly mature and capable of fertilization. Further refinement of the protocol is now needed to improve the yield of fully matured oocytes.

scholarly journals Selection of breeding roosters during artificial insemination by the reaction of tonic immobility

2020 ◽  
Vol 2 (1) ◽  
pp. 29-38
Author(s):  
Igor I. Popov ◽  
Svetlana A. Shabanova ◽  
Yulia V. Shoshina
Keyword(s):  
Artificial Insemination ◽  
Small Volume ◽  
Tonic Immobility ◽  
The Body ◽  
Phenotypic Characteristics ◽  
Main Attention ◽  
Immobility Reaction ◽  
New Methods ◽  
Genetic Potential ◽  
Selection Of

The profitability increase of using laying hens is associated with an increase in their productivity and reduction of maintenance costs. This problem can be solved by two approaches: new methods for increasing the genetic potential of economically useful traits of chickens are being developed, and methods of ensuring the fullest realization of this potential are being sought. The main attention is paid to the selection of roosters, whose breeding qualities largely determine the “saturation” of the flock with the desirable genotypes. Analysis of the results of our research shows that roosters, especially in the maternal form, allocate very small amounts of ejaculate when massaging; most males have a difficult reaction to the massage. Moreover, by the age of 240 days, under the influence of long training, the number of such roosters decreased to 20-25%. However, the roosters, who later began to respond to the massage, often released ejaculates with volumes up to 0.2 cm3. Studies have shown that in the group of roosters with a small volume of ejaculate, the highest percentage (29.2%) of roosters was with a bad reaction to the massage and only 8.3% of roosters was with a good reaction. In the group with a large volume of ejaculates, there are 64.8% more roosters with a good response to the massage compared to the I group and 67.8% compared to the II group. When describing the duration of tonic immobility reaction of roosters, who release ejaculates with different volumes during the massage, which, as indicated earlier, reflects the level of arousal and inhibition processes, it turned out that the least duration of the state of tonic immobility reaction was found in roosters that give small volumes of sperm (60%) and only 10% of males had a duration of tonic immobility reaction within 409-900 seconds. There is a violation of the normal flow of neuroreflective processes in the body in the roosters with an increased process of arousal, which is manifested, for example, during natural mating. Such roosters have a bad reaction to massage and give small amounts of sperm. Therefore, determining the level of hypnotic state in roosters, that is, identifying the degree of balance between arousal and inhibitory processes can serve as an additional criterion for the phenotypic characteristics of breeding roosters with a certain response to massage and the volume of ejaculate.

scholarly journals The incompletely fulfilled promise of embryo transfer in cattle—why aren’t pregnancy rates greater and what can we do about it?

2020 ◽  
Vol 98 (11) ◽  
Author(s):  
Peter J Hansen
Keyword(s):  
Embryo Transfer ◽  
Artificial Insemination ◽  
Blastocyst Stage ◽  
Pregnancy Rates ◽  
Bovine Embryos ◽  
Uterine Receptivity ◽  
Stage Of Development ◽  
Stage Embryo ◽  
Repeat Breeder ◽  
In Pregnancy

Abstract Typically, bovine embryos are transferred into recipient females about day 7 after estrus or anticipated ovulation, when the embryo has reached the blastocyst stage of development. All the biological and technical causes for failure of a female to produce a blastocyst 7 d after natural or artificial insemination (AI) are avoided when a blastocyst-stage embryo is transferred into the female. It is reasonable to expect, therefore, that pregnancy success would be higher for embryo transfer (ET) recipients than for inseminated females. This expectation is not usually met unless the recipient is exposed to heat stress or is classified as a repeat-breeder female. Rather, pregnancy success is generally similar for ET and AI. The implication is that either one or more of the technical aspects of ET have not yet been optimized or that underlying female fertility that causes an embryo to die before day 7 also causes it to die later in pregnancy. Improvements in pregnancy success after ET will depend upon making a better embryo, improving uterine receptivity, and forging new tools for production and transfer of embryos. Key to accelerating progress in improving pregnancy rates will be the identification of phenotypes or phenomes that allow the prediction of embryo competence for survival and maternal capacity to support embryonic development.

Ultrastructural observations on in vivo fertilisation in the brushtail possum, Trichosurus vulpecula, following PMSG/LH superovulation and artificial insemination

Zygote ◽  
1999 ◽  
Vol 7 (4) ◽  
pp. 307-320 ◽  
Author(s):  
M.K. Jungnickel ◽  
A.J. Harman ◽  
J.C. Rodger
Keyword(s):  
Artificial Insemination ◽  
Acrosome Reaction ◽  
Brushtail Possum ◽  
Trichosurus Vulpecula ◽  
Chromatin Decondensation ◽  
Large Hole ◽  
Enzymatic Action ◽  
Acrosomal Membrane ◽  
Sperm Penetration

Information on the dynamics of gamete interaction in marsupials is very limited and not available for any species from the major Australian Order Diprotodontia which includes most of the more familiar animals such as kangaroos, possums and the koala. This study addressed this deficiency by examining the ultrastructure of in vivo fertilised eggs from common brushtail possums (Trichosurus vulpecula). Females were superovulated by treatment with 15 IU PMSG and then 4 mg porcine LH 3 days later, and inseminations were performed 910-13 h after LH) using epididymal spermatozoa. Between 33 and 39 h after LH injection females were killed, reproductive tracts excised and the oviduct ampulla segment flushed for eggs. Three of the six eggs examined were fertilised as judged by the presence of sperm remnants in the cytoplasm. On the basis of these eggs it was found that sperm penetration left a large hole in the zona pellucida (ZP), suggesting that sperm zona penetration occurs primarily by the enzymatic action of acrosomal enzymes. Sperm lying within the perivitelline space were lacking both an outer acrosomal membrane and the associated acrosomal contents, while both these structures were found on sperm embedded within the mucoid layer, which is consistent with induction of the acrosome reaction by binding to the ZP. Once inside the egg cytoplasm, the sperm head travelled only a short distance before chromatin decondensation occurred. Fertilised eggs showed signs of cytoplasmic activation including cytoskeleton association with apparently dividing mitochondria and prominent rough endoplasmic reticulum. Unfertilised eggs appeared to be undergoing degenerative changes and lacked any evidence of activation. This study has demonstrated that superovulation and laparoscopic intravaginal artificial insemination provide a system through which perifertilisation events in the possum and other monovular Australian marsupials can be examined experimentally.

122. PRODUCTION OF EMBRYOS IN SUPEROVULATED EWES USING FROZEN - THAWED, SEX-SORTED AND REFROZEN - THAWED SPERM

2010 ◽  
Vol 22 (9) ◽  
pp. 40
Author(s):  
K. H. Beilby ◽  
Y. B. Kaurivi ◽  
W. M. C. Maxwell ◽  
G. Evans ◽  
S. P. De Graaf ◽  
...  
Keyword(s):  
Y Chromosome ◽  
Artificial Insemination ◽  
Blastocyst Stage ◽  
Corpora Lutea ◽  
Treatment Control ◽  
Embryo Production ◽  
Recovery Rates ◽  
Embryo Recovery ◽  
Flow Cytometric

Flow cytometric sex-sorting of sperm that has previously been cryopreserved allows sex-sorting technology to be applied more widely. While offspring have been produced following artificial insemination of synchronised ewes with frozen-thawed, sex-sorted and refrozen-thawed (FSF) sperm (1), the fertility of FSF-sperm in superovulated ewes has not been reported. The aim of this study was to determine the effect of cryopreservation prior to sperm sex-sorting and freezing on embryo production in superovulated ewes. Several ejaculates from 2 rams were either frozen-thawed, then sex-sorted and re-frozen (FSF X- and Y-chromosome enriched sperm), or immediately sex-sorted before freezing (SF X- and Y-chromosome enriched sperm). A portion of each ejaculate was also cryopreserved without sex-sorting (control). Thirty-one ewes were superovulated and inseminated (15 ×106 sperm per insemination dose) with either SF X, SF Y, FSF X, FSF Y or control sperm as previously described (2). Embryos were recovered 6 d after insemination and assessed. The superovulatory response (mean number of corpora lutea per ewe: 11.8 ± 1.3) and the embryo recovery rates (72.0 ± 5.9%) did not differ significantly among the groups. The fertilisation rates tended to differ (P=0.068) as a result of sperm treatment (control: 33%; SF: 54%; FSF: 18%) and were unaffected by sperm sex (X: 33%; Y: 37%). Of the embryos that were recovered, those derived from FSF-sperm were predominantly at the blastocyst stage (65%), whereas those derived from SF-sperm were evenly distributed among the blastocyst (30%), morula (38%) and arrested (32%) stages, suggesting that fertilisation lifespan of SF-sperm was greater than that of FSF-sperm. A greater proportion of embryos derived from Y-sperm were at the blastocyst stage compared with embryos derived from X-sperm (53% vs. 26%; P < 0.05). This study is the first to demonstrate that FSF-sperm is capable of fertilising oocytes of superovulated ewes. (1) de Graaf et al (2007) Theriogenology 67: 391–8.(2) de Graaf et al (2007) Theriogenology 67: 550–5.

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