At the Camel Reproduction Centre in Dubai, there are two adult female camels that are about 11 months pregnant, meaning they are due to give birth in March.
However, these are no ordinary pregnancies.
What makes them special is that the calves will be the first ones born at the CRC to females inseminated with semen that had been frozen.
It is the culmination of a four-year research programme to breed camels using frozen semen, something that has proved far more difficult than with many other large mammals.
While cattle, for example, are routinely bred using frozen semen, several factors have made success in dromedaries and other camel family members more difficult.
The CRC’s impending arrivals come hot on the heels of the first-ever camel produced from frozen sperm, a female calf named Bint Shaheen born at the Dubai Camel Breeding Centre earlier this month.
Efforts have taken place in parallel at the two centres as demand increases from the racing industry for new ways to generate offspring from prized racing camels. Indeed, Bint Shaheen’s name reflects that of her father, Shaheen, a champion animal whose semen was reportedly collected and frozen in late 2016. Other adult females at the Dubai Camel Breeding Centre are reportedly pregnant after being inseminated with frozen semen.
Dr Lulu Skidmore, scientific director at CRC that was founded by Sheikh Mohammed bin Rashid, Vice President and Ruler of Dubai, said it was “very exciting news” that a first live birth from frozen semen had happened at Dubai Camel Breeding Centre.
“It’s very good for the camel industry that we can freeze semen. We’ve got pregnancies coming,” she said.
“We’ve been working on it for the last four years or so. Because camels are becoming more important racing-wise and milk-wise, there’s more interest. That’s pushing more people into doing it. We’ve got a lot of clients now.”
Efforts to produce camels using frozen sperm have proved difficult for several reasons.
The volume of semen that camels produce is small, at 3ml to 8ml, a fraction of the quantity produced by some similarly sized animals such as horses. Also, the concentration of spermatozoa (male sex cells) in camel semen is low.
In addition, camel semen is gel-like and does not mix well with the substances added to it to ensure preservation during freezing, when the material is kept at -196C.
“We have to work on ways to reduce the viscosity [of the semen] and to keep them alive. You don’t want to treat them with enzymes,” said Dr Skidmore.
“We have investigated the use of different extenders, different cryoprotectants, such as glycerol and ethylene glycol, that protect the spermatozoa during the freezing process, and different freezing and thawing rates to get the best protocol for freezing semen.”
Dr Skidmore said the CRC, which lies off the Dubai – Hatta road, now achieves post-thaw spermatozoa motility (movement) rates close to 50 per cent. Pregnancy rates with frozen semen are about 25 per cent.
Efforts at the CRC to use frozen semen are spearheaded by Dr Clara Malo, senior scientist and head of andrology, and Dr Elizabeth Crichton.
Dr Claire Kershaw, a lecturer in farm animal health at Harper Adams University in the United Kingdom who has previously collaborated with the CRC, said it was “interesting” to hear that a camel had finally been born from frozen semen at the Dubai Camel Breeding Centre.
“I’m sure they’ve had these issues in optimising the media [the substances added to the semen] and trying to reduce the damage that occurs,” she said.
“As soon as you mix [camel semen] with anything, it doesn’t mix. You end up with blobs inside the gel; the sperm aren’t protected.”
There are a number of advantages linked to using frozen semen, instead of allowing the animals to mate.
It reduces the risk that disease will spread between the animals, and means that individuals that live far apart do not have to be brought together.
The libido of male camels “isn’t very good”, said Dr Skidmore, making it useful to be able to collect and freeze semen and inseminate multiple females. Frozen semen can be stored for many years and used after the male has died.
As well as freezing semen, the CRC also uses fresh semen for artificial insemination. In addition, it also works with chilled semen, in which the material is kept at 4C for up to 24 hours. This allows semen to be transported anywhere internationally that can be reached within a day. Pregnancy rates of 70 to 80 per cent have been achieved using chilled semen.
The CRC is among the centres in the UAE to use another technique, embryo transfer, in which multiple embryos produced from a cross between a particular male and female are inserted into surrogate females, who each carry and give birth to a calf. The technique allows a particular female to generate multiple offspring in a season. The embryos can, if necessary, be frozen and stored before implantation.
A 2012 scientific paper described how, between 1990 and 2010, nearly 11,500 embryos were transferred to recipient females as part of a breeding programme at a research centre in Swaihan. Between 1990 and 2009, these transfers led to the creation of more than 2,800 weaned calves.
Camels have also been cloned in the UAE, with the world's first produced by the CRC in 2009.
In another example of the UAE’s leading role in camel reproduction, the Reproductive Biology Centre in Dubai produced the first cloned Bactrian (two-humped) camel last year, although this calve did not survive long.