![]() ![]() To test this theory, canine semen was collected in a split ejaculate. 9 In theory, protecting semen from both temperature and pH shock upon collection would extend the functional life and fertilizing capability of the spermatozoa. While attempts are sometimes made to warm the collection container, the containers are still dry. In some species, such as the canine, zero percent motility can be reached in less than one hour. 4‒8 This shock to the sperm can result in loss of motility and fertilizing capability, rendering it virtually useless in a matter of a few minutes to a few hours. Sperm are especially susceptible to changes in temperature and pH. While this method does work, it may not be the most efficient method of extension. The common thread with the use of semen extenders and collection techniques is that the extenders have traditionally been added post-collection. Extended semen can be maintained for days (times vary depending on the species) and with the addition of a cryoprotectant, extended semen can also be frozen and remain viable (i.e., produce a pregnancy) for up to 20years. Semen extenders provide nutrients for sperm metabolism, carry additives such as antibiotics and cryoprotectants (for storage at lower temperatures), and provide multiple breedings from one semen sample. 2 These extenders were created in an attempt to hold sperm in a favorable environment for cellular survival while biochemically placing the cells in suspended animation (delaying their progression toward final maturity) until time for their use. The first successful, and by far still the most common, way to preserve semen for later use was with semen extenders. In order for AI to develop to its full potential, a method had to be discovered to preserve semen for use at a later date. 1 Realizing early on that raw, unprocessed semen lost fertilizing capability rapidly after ejaculation, it was discovered that the collected semen had to be used the same day (and in cases such as the dog, almost immediately in order to achieve good results- i.e. Since artificial insemination’s (AI) inception, in the 1300’s, and its first documented use in the 1780’s, AI has continued to be developed as a tool in both animal and human reproduction. Keywords: artificial insemination, canine, semen collection Abbreviations The data suggest the described collection technique can yield significantly more motile sperm by placing the sample into a physiologically favorable environment (eliminating pH and cold shock and allowing osmoregulation to begin), thus providing more available sperm for breeding. Modification of the semen collection/extension procedure resulted in improved semen parameters for extended time-periods post-collection. ![]() There was a difference between the treatment and control groups for Motility (P.05). Data analysis was performed with SPSS using the general linear model and appropriate t-tests. ![]() Standard semen parameters, available sperm pool, and number of inseminations were evaluated at specific time intervals and evaluations continued until samples reached zero percent motility. The control half was collected into a dry container and no attempts to maintain temperature was used. The treatment half of the sample was collected into a measured amount of warmed extension media. Ten canine semen samples were collected with a modified artificial vagina to allow for a true split collection into to collection containers at one time. The objective of this study was to determine if modifying the method of collection/extension of semen to include a warmed media environment would improve semen parameters by lessening cold and pH shock. To date, the common thread in the use of semen extenders/collection techniques, whether they are being used for fresh extended semen, chilled semen, or cryopreserved semen, is that the extenders have all traditionally been added post-collection. ![]()
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