{"Procedure":"<ol>\r\n\t<li>\r\n\t\tHomozygous mice (minimum age of 8 weeks, maximum age of 14 weeks) are mated for 4-6 weeks. Strains that produce no progeny or pregnant dams after 4 to 6 weeks progress to secondary screening.</li>\r\n\t<li>\r\n\t\tSecondary Male Infertility Screen:\r\n\t\t<ol type=\"a\">\r\n\t\t\t<li>\r\n\t\t\t\tSet up 2 separate matings: male Hom x female WT or Het\r\n\t\t\t\t<ol type=\"i\">\r\n\t\t\t\t\t<li>\r\n\t\t\t\t\t\tObserve matings for 4 to 6 weeks;</li>\r\n\t\t\t\t\t<li>\r\n\t\t\t\t\t\tMatings that result in visibly pregnant females (confirmed by dissection) or pups will be scored MALE FERTILE.</li>\r\n\t\t\t\t\t<li>\r\n\t\t\t\t\t\tMatings that do not result in pregnancy will be scored MALE INFERTILITY.</li>\r\n\t\t\t\t</ol>\r\n\t\t\t</li>\r\n\t\t</ol>\r\n\t</li>\r\n\t<li>\r\n\t\tSecondary Female Infertility Screen\r\n\t\t<ol type=\"a\">\r\n\t\t\t<li>\r\n\t\t\t\tSet up &nbsp;2 separate matings: female Hom x male WT or Het</li>\r\n\t\t\t<li>\r\n\t\t\t\tObserve matings for 4 to 6 weeks;\r\n\t\t\t\t<ol type=\"i\">\r\n\t\t\t\t\t<li>\r\n\t\t\t\t\t\tMatings that result in visibly pregnant females (confirmed by dissection) or pups will be scored FEMALE FERTILE.</li>\r\n\t\t\t\t\t<li>\r\n\t\t\t\t\t\tMatings that do not result in pregnancy will be scored FEMALE INFERTILITY.</li>\r\n\t\t\t\t</ol>\r\n\t\t\t</li>\r\n\t\t</ol>\r\n\t</li>\r\n</ol>\r\n","Purpose":"<p>\r\n\tTo assess the fertility of homozygous knockout mice.</p>\r\n","Experimental Design":"<ul>\r\n\t<li>\r\n\t\tMinimum 1 hom x hom mating for fertile mice and minimum of 2 failed hom x hom matings attempts to proceed to secondary screen.\r\n\t\t<ul>\r\n\t\t\t<li>\r\n\t\t\t\tSecondary screen: &nbsp;Minimum 2 Hom x 1 WT or Het (Male) , Minimum 2 Hom x 1 WT or Het (<a>Female)</a></li>\r\n\t\t</ul>\r\n\t</li>\r\n\t<li>\r\n\t\tMinimal age at test = minimal age at start of procedure = 8 weeks.</li>\r\n\t<li>\r\n\t\tMaximum age at test = To be confirmed, proposed 14 weeks</li>\r\n\t<li>\r\n\t\tMinimum length of test (time mice left in mating) 4 - 6 weeks</li>\r\n</ul>\r\n","Notes":"<p>\r\n\tPregnancies should be confirmed.</p>\r\n<p>\r\n\tAll annotations are based on yes/no scores.</p>\r\n"}