COMPOSITIONS AND METHODS FOR REDUCING AGGLUTINATION AND IMPROVING HEALTH OF SEX-SORTED SPERM CELLS

1 . A method of reducing agglutination and improving health of sperm cells having an altered ratio of viable X chromosome-bearing sperm cells to viable Y chromosome-bearing sperm cells comprising:

staining a sperm cell sample comprising viable X chromosome-bearing sperm cells and viable Y chromosome-bearing sperm cells with a staining media comprising a DNA selective dye;

contacting the stained sperm cell sample with a sheath fluid in a flow path;

altering a ratio of the viable X chromosome-bearing sperm cells to the viable Y chromosome-bearing sperm cells to form at least one altered sperm cell population; and

collecting the altered sperm cell population in a collection media comprising egg yolk at a wt./vol. concentration of 10% or less and a low-density lipoprotein additive, thereby reducing agglutination and improving health of the sperm cells in the collected sperm cell population.

2 . The method of claim 1 , wherein the step of altering a ratio of the viable X chromosome-bearing sperm cells to the viable Y chromosome-bearing sperm cells to form at least one altered sperm cell population comprises i) removing at least a portion of one of either the viable X chromosome-bearing sperm cells or the viable Y chromosome-bearing sperm cells from the sperm cell sample or ii) photo-damaging at least a portion of one of either the viable Y chromosome-bearing sperm cells or the viable X chromosome-bearing sperm cells.

3 . The method of claim 1 , further comprising the steps of injecting the stained sperm cell sample into a flow of sheath fluid;

exposing the stained sperm cell sample in the flow of sheath fluid to an electromagnetic radiation source that causes a detectable response in the DNA selective dye;

detecting the response of the DNA selective dye to the electromagnetic radiation exposure;

analyzing the detected response; and

classifying sperm cells in the sperm cell sample based on the analysis of the detected response.

4 . The method of claim 1 , wherein the egg yolk is at a wt./vol. concentration between 0.01% to 10%.

5 . The method of claim 1 , wherein the egg yolk is at wt./vol. concentration of between 0.01% to 5%.

6 . The method of claim 1 , wherein the egg yolk is at a wt./vol. concentration of between 0.01% to 1%.

7 . The method of claim 1 , wherein the egg yolk is at a wt./vol. concentration of between 0.01% to 0.5%.

8 . The method of claim 1 , wherein the egg yolk is at a wt./vol. concentration of between 0.01% to 0.05%.

9 . The method of claim 1 , wherein the egg yolk is at a wt./vol. concentration of 0.01%.

10 . The method of claim 1 , wherein the egg yolk is at a wt./vol. concentration of 0%.

11 . The method of claim 1 , wherein the low-density lipoprotein additive is extracted from pasteurized egg yolk.

12 . The method of claim 1 , wherein the low-density lipoprotein additive is at a wt./vol. concentration of between 0.5% to 30%.

13 . The method of claim 1 , wherein the low-density lipoprotein additive is at a wt./vol. concentration of between 0.5% to 10%.

14 . The method of claim 1 , wherein the low-density lipoprotein additive is at a wt./vol. concentration of between 0.5% to 5%.

15 . The method of claim 1 , wherein the low-density lipoprotein additive is at a wt./vol. concentration of between 1% to 5%.

16 . The method of claim 1 , wherein the low-density lipoprotein additive is at a wt./vol. concentration of 2.5%.

17 . The method of claim 1 , wherein the low-density lipoprotein additive is at a wt./vol. concentration of between 1% to 5% and the egg yolk is at a wt./vol. concentration of between 0.01% to 1%.

18 . The method of claim 1 , wherein the sperm cells are porcine sperm cells or bovine sperm cells.

19 . The method of claim 1 , wherein the step of collecting is conducted at a temperature less than 37° C.

20 . The method of claim 1 , wherein the step of collecting is conducted at a temperature less than 22° C.

21 . The method of claim 1 , wherein the low-density lipoprotein additive is extracted using polyethylene glycol.

22 . The method of claim 1 , wherein the collection media further comprises vitamin B or alpha-ketoglutarate.

23 . A composition comprising:

egg yolk at a wt./vol. concentration of between 0.01% to 0.05%;

a low-density lipoprotein additive at a wt./vol. concentration of between 1% to 5%; and

a sperm cell sample comprising an altered ratio of viable X chromosome-bearing sperm cells to viable Y chromosome-bearing sperm cells.

24 . The composition of claim 23 , wherein the low-density lipoprotein additive is extracted from pasteurized egg yolk.

25 . The composition of claim 23 , wherein the sperm cell sample in the composition has an agglutination rank of 2 or less.