In boar studies, only about 50-60% of the sperm in the epididymis are ejaculated the first time. It is probably similar in dogs, and explains why a second ejaculate will have 70% of the amount of sperm that the first one did. If they are collected, say, every 24 hours for 10 days in a row, though, the count will drop dramatically because the epididymal reserves will have been depleted to a point that is representative of his daily sperm production. At this point of depletion, as Cathy mentioned, more immature sperm may be pushed through before they are ready. Once their epididymal reserves are totally depleted, it takes 6-7 days (in the pig, anyway) to build back up the supply in the epididymis.
In boar studies, there was greater volume obtained per unit of time when collections were every 72 hours or 3x per week, as opposed to every 24. But that is in boars that are being collected all year long for the purpose of artificial insemination. For those that are not collected at all, the dead ones just pass through the urine. I would say that if you have progesterone testing (or a very helpful stud dog or reliable bitch) and are only going to do 2 or 3 breedings, then breeding every 24 hours is fine. But if you are like some breeders, and breed over a period of nearly 2 weeks, then the optimum is probably every 48 hours, in order to avoid totally depleting the epididymal reserves. Leanne ========================================================= "Magic Commands": to stop receiving mail for awhile, click here and send the email: mailto:[EMAIL PROTECTED]?body=SET%20CKCS-L%20NOMAIL to start it up gain click here: mailto:[EMAIL PROTECTED]?body=SET%20CKCS-L%20MAIL E-mail [EMAIL PROTECTED] for assistance. Search the Archives... http://apple.ease.lsoft.com/archives/ckcs-l.html All e-mail sent through CKCS-L is Copyright 2002 by its original author.
