R E P R O D U C T I V E
M A N A G E M E N T
J When conducting A.I., emphasis should be placed on depositing semen in the uterine body.
Semen Deposition
The uterine body has been the accepted site for semen deposition during A.I. The following table, modified from Williams, B.L., et al. (1988), shows the overall conception for semen deposited in the uterine body or the cervix. From the table, it is clear semen deposited in the cervix has lower conception ability. Some research attributes this lower conception to the issue of sperm being trapped, resulting in sperm loss. Therefore, emphasis should be made to ensure new breeders have no trouble passing the pipette through the cervix to deposit semen in the uterine body. o Table 1. Comparison of conception when semen is deposited into the uterine body or the cervix
Semen Deposit
Uterine Body
Cervix
%, conception (n) = breeding animals
48.1 (975)
39.4 (66)
Another example from Graves, et al., (1991) from the University of Tennessee describes that 502 animals were inseminated either in the uterine body or the semen was deposited in both horns. The results shows that conception for semen deposited in the uterine body was 62.9% compared with 54.2% conception for semen deposited in both uterine horns. The researchers agree with the A.I. industry recommendation that deposition of semen should occur in the uterine body. In conclusion, according to the literature, depositing semen in the horns may not increase the conception compared with depositing semen in the uterine body. However, consistency in depositing the semen in the body of the uterus and not in the cervix will deliver better results. Also consider other recommendations for semen handling and proper A.I. technique that must be followed to increase the chances of getting more cows pregnant. Contact your local Genex representative for more information or for A.I. training.
Adapted from: Williams, et al., 1988. J Dairy Sci.71:2278-2283
References k
As I mentioned previously, it is a popular belief that depositing semen directly into the uterine horns will increase conception rate because the semen has made it past the mucous barrier of the cervix and is positioned closer to the uterine ampulla where semen attaches to its wall and waits until ovulation occurs. This concept sounds logical, however literature does not completely agree. A literature review from Dejarnette, et al., (2004) analyzed 17 studies conducted from 1944 to 1999 which compared the effects on fertility from semen deposited in the uterine horns or the uterine body. Twelve studies, accounting for 26,828 breedings (13,413 in the uterine body and 13,415 in the uterine horns), did not find any statistical difference between either location for semen deposit. In conclusion, the extra effort and training for depositing the semen in both horns will not be compensated with an increase in conception. It is not clear why a few studies show an advantage from depositing semen in the horns. One possible explanation is related to depositing semen in the horns to minimize the semen being deposited in the cervix.
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DeJarnette, J. M., C. E. Marshall., R. W. Lenz., D. R. Monke., W. H. Ayars and C. G. Sattler. 2004. Sustaining the fertility of artificially inseminates dairy cattle: the role of the artificial insemination industry. J Dairy Sci. 87: 93-104 Graves, W. M., H. H. Dowlen., G. A. Kless and T. L. Riley. 1991. Evaluation of the uterine body and bilateral uterine-horn insemination techniques. J Dairy Sci. 74:10 3454-3456 O’Connor M. L. Artificial Insemination Technique. The Pennsylvania State University. Dairy Integrated Reproductive Management Williams, B. L., F.C. Gwazdauskas., W. D. Whittier., R. E. Pearson and R. L. Nebel. 1988. Our industry today: Impact of site of inseminate deposition and environmental factor that influence reproduction of dairy cattle. J Dairy Sci. 71: 2278-2283
A Author Bio: Gustavo Peña earned his master’s degree in dairy management from Utah State University and a doctorate of veterinary medicine from Mexico State University. He completed his residency at the University of Florida. Gustavo served as a Genex National Account Specialist in Texas until early 2013 and now works for Animal Diagnostics.
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