|Title||Effects of liveweight gain of 15-month-old Angus heifers during the first trimester of pregnancy on liveweight and milk intake of their calves|
|Publication Type||Journal Article|
|Year of Publication||2009|
|Authors||Hickson, R E., Kenyon P R., Lopez-Villalobos N., and Morris S T.|
|Journal||New Zealand Journal of Agricultural Research|
|Pagination||39 - 46|
|ISBN Number||00288233 (ISSN)|
Nutritional methods of manipulating birthweight of calves would be benefcial for managing dystocia in beef heifers. Sixty-five 15-month-old Angus heifers were managed under the following liveweight gain treatments for the frst 42 days and then from 42 to 90 days of pregnancy: treatment 1: high liveweight gain throughout (881 ± 59 g/day and 212 ± 45 g/day); treatment 2: low liveweight gain throughout (182 ± 60 g/day and -565 ± 47 g/ day); and treatment 3: low then high liveweight gain (217 ± 59 g/day and 379 ± 44 g/day). Heifers were managed in one herd from day 90 of pregnancy until parturition. Birthweight of calves was not affected by treatment, and was 32.3 ± 0.9 kg, 32.9 ± 0.9 kg and 32.5 ± 0.9 kg for treatments 1, 2 and 3, respectively. calves born to heifers in treatment 2 consumed less milk at 90 days of age than calves from heifers in the other treatments (P < 0.05). Liveweight gain restriction in the frst trimester of pregnancy did not reduce birthweight of calves, and therefore could not be used to manage dystocia in heifers.