פירוש על ויקרא 3:6

זכר או נקבה, “male or female.” In connection with the flocks the Torah writes זכר או נקבה, whereas in connection with the sacrificial animal בן בקר, a young bull, we have the wording אם זכר אם נקבה. The reason for the different wording is that the word או is necessary to include the פלגס, a sheep thirteen months old, so that a plural mode is needed here. The word אם does not allow for use in a plural mode.