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Show About Sheep Breeding FROM the hreedlng records of 514 ewes It was determined that for ordinary animals and conditions the normal period of geiti-tion geiti-tion ranges from 144 to ISO days after the date of service and that more ewes will lamb 145 days after service than at any other time. There Is no appreciable difference In tho period of gestation for male and female offspring off-spring In sheep and there Is an apparent relation between tho duration of the period of gestation and the period required for reaching maturity. Quick-maturing breeds appear to carry their young for a shorter period than those breeds requiring more time I to mature. Large lambs are on the vcrnge carried In utero for an appreciable longer period than small or medium lambs. Lambs dropped before the 144th day and after tho 143th day of pregnoncy are lacking in strength and vitality at birth. Shropshire ewes were more prolific than any of the other breeds and crosses used except the fourth cross of Shropshire rams on a Merino ewe foundation From tjie data presented It Is apparent that twins are tho normal Increase for ew es of the mutton t pe. One-year-old rams arc not so prolific as thoe 2 or 3 years old. Ewes also average a larger percentage of Increase In lambs after thoy reach full maturity at 3 years of ago until after they are f, years old, when th rate of Increase diminishes. The amount of service required of the ram In breeding hai an Influence on the percentage of Increase Is. offspring of the ev.es that produce lambs. Fwe? bred early In tho season of mating to n sincle ram dropped a larger percentage of l.irohs than thoso near tho latter end of the season. |