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Embryo transfer at Coolaroo Alpaca Stud

By Earl Barnes,2014-05-08 21:49
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Embryo transfer at Coolaroo Alpaca Stud

    Embryo transfer at Coolaroo Alpaca Stud

    By Janie Hicks

    Introduction:

    Embryo Transfer has produced a revolutionary change in breeding results since the first successful implantation of embryos into recipient females at Coolaroo in 2003. This was the beginning of a fascinating programme, shared by Coolaroo clients and ongoing at Coolaroo with some 100 plus births to date and a further 90 in utero and due by November 2007.

    Coolaroo’s stud breeding began in the US transferring to Australia in 1988, but it was not until 1995,

    with some 400 breeding females that we adopted advanced breeding methods with the employment of Dr Jim Watts. Prior to alpacas our family had run livestock as their livelihood, principally 38,000 merino sheep so working with a breeding consultant was paramount to our future as fleece producers. Trials began as the direct result of accumulative knowledge of specialists in breeding selection adopting the SRS? Breeding strategy and trialling embryo transfer initially with Dr Peter Howe who collected our first embryos in 1997. However it was not until 6 years later that Drs Jane Vaughan and David Hopkins successfully implanted embryos into recipient dams at Coolaroo birthing healthy cria in the following year.

    I hasten to add that much of the content of this paper is attributed to the expertise of those mentioned above and thank them for it.

    The first embryos looked spherical but there has been an assortment of shapes and sizes that have grown into normal shaped cria too.

    What is Embryo Transfer (ET)?

    Not pretending to be an expert I shall provide the background notes kindly supplied to me by Dr Jane Vaughan

    Embryo transfer (ET) is the process by which embryos are harvested from valuable female alpacas and transferred into less valuable females for incubation and nurturing. Each donor female is mated naturally by a male, which (a) induces her to release an egg into the oviduct and (b) deposits sperm in

    the female reproductive tract. The union of the egg and sperm (fertilisation) in the oviduct results in

    the development of an embryo, which can be harvested from the uterus about a week after mating.

    Donor females are lightly sedated and flushed non-surgically. Embryos are transferred into

    reproductively-sound recipient females of lesser genetic merit. The donor female can be mated and

    flushed in subsequent weeks to allow more embryo collections and transfers. Thanks Jane

    Why ET in the Coolaroo herd?

    1. Coolaroo’s skin testing research in line with SRS?breeding principles quickly established

    a vast difference of follicle density between one alpaca and another. How could we infuse qualities of

    greater genetic merit into our herd?

    2. Alpaca’s gestation is a long (relatively speaking) 11.5 months, 6 months longer than a

    sheep, and they do not as rule, multiple birth. Breeding programmes are slow relative to other

    livestock such as goats and sheep. How to fast track upgrading our herds?

    3. Coolaroo’s alpaca population, imported initially from low density herds in Northern Chile,

    had unpredictable colour genetics, browns, blacks, spots and white faces to name a few. Many of

    these early imports were dated. Already progeny, a result of rigorous breeding selection, exhibited

    and tested twice the follicle density to their dams. Colour outcomes had become more predictable.

    The question would arise, what is to be done with these grand dams?

    4. In a shipment in 1991 we had inadvertently imported 3 animals that carried genetic thdisorders which resurfaced every second generation. Some of these lines were now into their 4

    generation. What could be done with these lines not welcome in the herd’s genetic pool?

    5. And culls……..all stud masters have culls or those animals which do not meet with the

    breed selection criteria. In Peru and in other livestock we send them to market for human

    consumption. However, without this option in the current industry in Australia, how do you cull stock

    with blue eyes, lines carrying susceptibility to rye grass, those with poor disease resistance or other

    negative traits.

    6. Infertility due to scarring or damage to the uterus. A female of considerable genetic merit

    that cannot give birth naturally may be worth persevering with if the successful collection of embryo is

    achievable. We have had mixed results with these females.

    Further advantages and pitfalls

    ; ET allowed us to produce a lifetime of cria from any one female in a matter of a year or

    two. This enables a stud master to make a breeding decision quickly and effect a change of joining or

    a reclassification up to elite donor level or down to natural stud reproduction.

    For example: In 2004/5 we trialled a highly prolific young female carrying a single spot on her neck.

    How would this spot affect the colour of her progeny? Both her dam and sire had been registered as

    solid white of Peruvian origin but, as with most alpacas that are imported, we had no further genetic

    history. We involved her in 4 programmes changing the sire on each occasion. The results were:

    Two multi cria and two solid coloured cria by the same male. All other eight cria by other males were

    solid coloured. In a single year we were alerted to the importance of actively diluting that multi gene

    by careful selection of joining sires. Such information is normally accrued over years of breeding. ; Fast tracking the breeding programme identified the flaws in donor selection but having

    done so it allowed us to move to rectify selection for the next programme. Conversely it identified

    sound’ donors equally efficiently.

    ; ET ensures the reproductive tract of the donor alpacas is regularly examined. In a larger herd, unless ultra sounded specifically it may take years to learn a female has a reproduction flaw such as undersized ovaries, found last year in one of the ‘elite’ females, now culled.

    ; Costs versus risk needs careful analysis per individual breeder’s circumstances but suffice to say that, whilst ever quality alpacas are rare in the world’s market place ET, even its developmental

    stage, is well worth promoting to ensure its continued development to greater commercial merit. Costs are variable depending on the result 12 months after fees are paid depending on your male/female ratios and birthing rates. Costs to consider are drugs, travel costs for the vets, flushing and implantation costs as well as sire stud fees. There may be agistment costs if you are ‘borrowing or

    leasing your recipients but these all vary from operator to operator.

    In summary the advantages of ET to Coolaroo and to Coolaroo clients are:

    ; ET is a powerful tool to genetically improve a herd

    ; It has lessened the distance to the goalposts

    ; It has shifted the entire stud breeding female base to a new level

    ; It has increased the impact of genetically superior bloodstock

    ; It has harnessed genetically inferior stock which may have otherwise become redundant.

    ; It has culled ‘without slaughter’ genetically inferior stock

    ; It harnesses genetically superior females which may not either wise able to breed due to

    past birthing damage.

    ; Identifies reproduction problems in individual females

    Selection of Donors and Recipients

    Selection of recipients and donors has been by trial and error. It is risky to purchase a female as a donor when only 1 in 3 or thereabouts react to the treatment and this needs to be taken into account when you evaluate your purchase females. Equally, whilst recipients are of lesser value it is also paramount the animal has an excellent breeding history, amongst other things.

    The right Donor

    Only exceptional animals of high impact genetic merit should be donors or the programme will be ineffective and breeding results will not be satisfactory given the extra cost to land your cria on the ground. Worthwhile animals in donor programmes should have advanced wools and other genetic merit according to the SRS? Breeding criteria.

    The right Recipient

    Its easy to underrate the recipient but it is highly costly to do so. Females that do not conceive easily cause losses post transfer. Later, females that are of poor maternal merit i.e. small in frame that could experience birthing problems, poor doers, poor milkers or showing signs of age or fall back to low body scores when feeding their young, all increase the risk of loss

    Coolaroo’s ET programme

    With some years of trial and error I would hesitate to recommend this advanced breeding procedure to the faint hearted. It has its risks but it is balanced by significant benefits.

    Coolaroo provides this service to clients keen to access our donor and sire genetics as well as a tried and tested pool of recipients. Our best results, (up to 13 embryos in a single flush) that

    survived through to weaning as crias, came from healthy donors and recipients that were carefully selected for the role.

    For more information about the Embryo Transfer programme for your stud, at Coolaroo contact Janie Hicks or Neil Parker. Mob: +61 (0) 419 99 555 3 or land line + 61 (0) 2 48785 266 or E-mail:coolaroo@hinet.net.

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