BIRTH OF A MALE LAMB DERIVED FROM AN IN-VITRO MATURED OOCYTE FERTILIZED BY INTRACYTOPLASMIC INJECTION OF A SINGLE PRESUMPTIVE MALE SPERM

The developmental competence of in vitro matured ovine oocytes, cytopl asmically injected with single male or female chromosome-bearing sperm , was investigated. Eighty-five unsorted, 92 'female-sorted' and 74 'm ale-sorted' ram sperm were injected into in vitro matured sheep oocyte s and, two to four hours later, placed into the oviducts of 28 oestrou s sheep, The sperm were separated according to sex by analysis of thei r DNA content with a now cytometer. One pregnancy was diagnosed by ult rasound after 55 days and a 3 kg male lamb was born after 150 days ges tation, This lamb was derived from an oocyte injected with 'male-sorte d' sperm.