Progesterone- remain high during pregnancy and form by c. lutinum and maintains the pregnancy.
Relaxin – produced by the placenta, appears about 14 days. Only found if have implantation. Peak about day 40/50 and will remain high untill they give birth. (it soften and relaxing of ligaments)
Prolactin – produced in the pituitary so produce mammary development/ milk development and peaks at parturition.
reproductive question answers
Pros – permits disease control as able to pull animals genes that are known not to have the disease. Reduces the possibility of injury to the mare and/or stallion. Able to use on animals which have a poor breeding technique or are injured. Permits evaluation of the semen at each collection point and are able to check quality for each animal. Aid in identifying reproductive problems. Prevents overuse of an animal. Permits use in older animal or animals with abnormalities. Increase the gene pool of an animal. Results in higher pregnancy rates.
Cons- technology is involved, operators need to be well trained with specialist equipment, requires more time than natural services. Improper cleaning of the equipment can lead to lower fertility, spreading of diease can be increase if testing is not done. Need to know heat period of the animal. The semen has to be stored correctly otherwise it will be no longer viable, may lose genetic varation.
Advantage- possible to have an increased conception rate, mare and stallions can be breed together that would other wise be geographical impossible to do, mares and foal not subject to transport stress, mare can remain in training/ work owner will save money in transport cost, reduction in the spread of some diseases. Disadvantages- veterinary costs are higher, mare owner must tease mares, arrange semen collection and transport and communicate with the veterinary surgeon and the stud farm, repeat inseminations lead to increase semen cost, frozen semen conception rates can be poor. (gift) gamete intra-fallopian tube transfer. Gift has been successful and is offered commercially by a few institutes. Gift involves the surgical deposition of an oocytes and sperm into the oviduct of a recipient mare. It seems the oviduct plays a crucial role in providing the correct enviroment for conception. advantage- reduces the requirments to transport the animal, it is a way to overcome some quarantine restrictions, increase gene poolavaliable to an indavidual breeding within a country, reduces the diease risk that is present when an unknowen animal enters a kennel for mating, may be useful when natural mating is difficult. Disadvantage
