Some reproductive patterns in sheep under desert conditions

l- :Blood ’S~T.UlIl vitamjn A concentrations o:f eighty~eight ewes (20 Alvassi, 16 ~xki~ 20 Merino, 15 Awassi~Barki and 17 -Mer:ino-J3arki ewes) were det.arm:”tned, us fug theCa~c-.Pr1.u~ method, but an al.tc:rne;te chzomogen, ’bhe tri-fluoro-acetlc ac td was r.oeomm~ded.2- T.he Lowes t (13.,4 p.g) and the highest (54000. p.gper 100 - ml.) values WeJJ:a ~cordGd :for an:ima1.s belo.ng:ingto. the same group o.f ovarian a.ctivity, that is ovaz Leawith both GT-aa£ian ~OLlicleE and corpora lutea. Furtba:r~more, a range o~ 24.9 and 38 9 p.g/100 ml.. reporte.d :foxthe group of ovaries having no s tzuo’tuz-e , :i.ndlcated thatovarian inactivity in the$e ewes is caused by’ £actorsother ~than Low leve1 of v1tamin As3- A very wide :range was noted in al.1. breeds stu.died.Absence of a statisticaU.y significant b:t:aed di:f:fe:r€lIl.cesund ez the same environmental. conditions :LudicateJi thatewes z-es ponded similarly witl1 :regard to vitamin .A metabo-lism