The Stimulation of Fertile Oestrus following Spring Lambing in Machine Milked Border Leicester X Merino Ewes
نویسندگان
چکیده
Groups of adult lactating Border Leicester cross Merino ewes which had lambed in the spring and had been milked mechanically after the lambs had been weaned at birth, were joined with Dorset Horn rams approximately 60 days after parturition. The ewes had been treated with progestogen sponges and pregnant mare’s serum gonadotrophrin (750 and 1500 I.U.) prior to the time of first or second expected oestrus.
منابع مشابه
Lamb Production from Booroola X Collinsville Ewes
Booroola Merino, Border Leicester and Collinsville Merino rams were joined in three successive years to Collinsville ewes and ewe progeny from all three groups were subsequently joined with Dorset Horn rams at Leeton Agricultural Research Station. When data were analysed for performance at up to five joinings and lambings, there were significant differences among the ewe groups in ovulation rat...
متن کاملThe Effect of Post-lambing Interval on Fertilisation in Lactating Ewes Treated with Progestagen Impregnated Sponges and Gonadotrophin
For Border Leicester x Merino ewes joined in October in their normal anoestrous period at 5 and 8 weeks post partum, the percentages raddled by rams within seven days after sponge removal were 78 and 82. The percentages of ewes with fertilised eggs (of raddled ewes yielding eggs) were 27 and 70. In Merino ewes joined at 4 and 8 weeks post partum, in July, the percentages of raddled ewes were 97...
متن کاملAn Effect of Previous Nutritional Treatment on the Ovulation Rate of Merino Ewes
The expression of oestrus in ewes may be influenced by previous nutritional *history. Smith (1966) reported that restricted nutrition during the spring delayed or reduced the expression of oestrus in Merino ewes during the following autumn, even though nutrition had been improved and ewe live weights had recovered before the rams were introduced. Hunter (1962) and Smith (1962) have also suggest...
متن کاملThe Influence of Time of Lambing on the Performance of Fine Wool Merino Ewes
Observations were carried out at Lismore in western Victoria on the performance of two groups of 250 fine wool Merino ewes mated in spring (November) and autumn (May) respectively. A greater proportion of ewes lambing in spring lambed within 150-170 days after the introduction of the rams than ewes lambing in autumn. The duration of lambing was shorter in spring. There were no significant diffe...
متن کاملA Comparison of the Reproductive Performance of Javanese Thin-tail and Border Leicester X Merino Ewes in Indonesia
Lamb production was measured over an 18 month period from 30 Javanese thintail (JTT) and 30 Border Leicester x Merino (BLM) ewes run continually with rams of several breeds. The study was carried out in West Java, Indonesia. One hundred and forty-eight lambs were born to JTT and BLM ewes respectively, the difference being associated with both a larger number of lambings and a higher incidence o...
متن کامل