Abstract
The mean length of the gestation period for 600 Angora does was 149.2 days. A three-year summary of the kidding records of 317 Angora does showed that 66% of the does kidded between the 8th and 12th day of the kidding season and further study of this data suggests that there was an interval of approximately 10 days between the placing of the male with the does on September 20 and the occurrence of the first estrus of the breeding season. The presence of the male with the does just prior to the start of the breeding season had a stimulating effect upon the initiation of estrus and ovulation. This was shown by slaughter studies in which 15 of 17 does which had run with males for 10 days had ovulated as compared to only 1 of 17 in a control group. This phenomenon was further demonstrated by breeding studies with 63 does. The exposure of one group to a vasectomized billy beginning 10 days prior to the start of the breeding season resulted in a significant difference in the mean kidding date between them and a similar control group. A grouping of births was observed in both the stimulated and control group, but the characteristic time lag experienced with the breeding flock in earlier years was absent from the control group. This fact suggests that possibly other factors as well as the presence of the male may serve to initiate and synchronize breeding activity of the does. Copyright © . .

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