|Title||Profitability of calving heifers at 2 compared with 3 years of age and the effect of incidence of assistance at parturition on profitability|
|Publication Type||Journal Article|
|Year of Publication||2010|
|Authors||Hickson, R E., Lopez-Villalobos N., Kenyon P R., Ridler B.J., and Morris S T.|
|Journal||Animal Production Science|
|Pagination||354 - 358|
|ISBN Number||18360939 (ISSN)|
There is potential to increase the profitability of beef-breeding cows in New Zealand by calving heifers for the first time at 2 instead of 3 years of age; however, calving at this earlier age is often associated with an increase in assistance at calving. This study used a simulated farm system within the Grazing Systems Model to estimate the profitability of calving heifers at 2 years of age with various incidences of assistance at calving. Annual profit from the beef cattle herd was greater for primiparous 2-year-old heifers than for 3-year-old primiparous heifers when the incidence of assisted calving in 2-year-old heifers was less than 89%. Replacement rate increased with increased assistance at parturition. These results indicated that a considerable gain in profitability could be made by calving heifers for the first time at 2 instead of 3 years of age, and further gains could be made in herds already calving heifers at 2 years of age by reducing the incidence of assistance at calving. © 2010 CSIRO.