The Effect of Ram Percentage on the Fertility of Maiden Ewes
نویسندگان
چکیده
The effect of ram percentage on the fertility of maiden ewes joined in autumn was examined on ten properties in New South Wales. On four of these properties a group of maiden ewes was joined to one per cent of rams and another group to three per cent. On another two properties the design was similar, but a third group containing maiden and mature ewes was also joined to one per cent of rams. On the other four properties two mixed flocks containing maiden and mature ewes were joined to 1 or 3 per cent of rams. Experienced rams were used in all treatments and a total of 4,900 ewes were involved. Raddle marks were recorded fortnightly during a six week joining period, and the number of dry ewes was determined after lambing.
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