The relationship between sperm function and diet: toms are what they eat

Authors: Long, Julie; LIU, JIANAN - US Department Of Agriculture (USDA)

Submitted to: Midwest Poultry Federation Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 3/15/2016
Publication Date: 3/18/2016
Citation: Long, J.A., Liu, J. 2016. The relationship between sperm function and diet: toms are what they eat. Midwest Poultry Federation Proceedings. 1-12.

Interpretive Summary: The fertility rates of frozen/thawed turkey semen is highly variable and, although ongoing research has identified some physiological basis for the poor fertility, there are turkey lines considered to be “at-risk” which would benefit from immediate cryobanking. In this study, a different strategy was investigated to improve the fertility of frozen/thawed semen from four unique turkey research lines. Males were fed diets containing different types of oils for three weeks prior to semen freezing. It was found that diets containing fish oil, soybean oil or a combination of these two oils changed the type of lipid in the sperm membrane and improved the fertility of frozen/thawed semen. Studies are underway to further investigate the merit and feasibility of this approach.

Technical Abstract: It is well known that cryopreserved semen could be used to regenerate commercial or research poultry lines; however, fertility rates from poultry semen frozen with current methods are not reliable enough for germ-line retrieval, especially from lines with low reproductive efficiency. As part of a long-term research plan to determine how and why poultry sperm lose functional competence during hypothermic semen storage, several factors have been identified that may help to improve poultry sperm cryopreservation (Long, 2006; Long and Guthrie, 2006; Peláez and Long, 2007; Blanco et al., 2008; Peláez and Long, 2008; Long et al., 2010; Blanco et al., 2011; Peláez et al., 2011; Long and Conn, 2012). This systematic approach to delineate the physiology responsible for poor sperm cryosurvival, and thus provide mechanisms to improve sperm cryopreservation, does not address the immediate need for preservation of germplasm from poultry stocks that are currently “at-risk”. To provide a short-term solution for preservation of semen from “at-risk” poultry lines, we are investigating an alternative strategy in the form of temporary dietary modification and/or in vitro manipulation of membrane cholesterol that also should be useful for the long-range goals of improving poultry sperm cryopreservation. Specifically, the goals are to: 1) alter the fat source in the diet to improve cryosurvival of turkey sperm by modifying the sperm membrane lipid composition; 2) change the cholesterol:phospholipid (C:P) ratio in the sperm membrane to improve sperm cryosurvival; and 3) determine if the combination of diet modification and in vitro manipulation of cholesterol content has a synergistic effect on sperm cryosuvival.