- Pre-joining
- Establish a joining date and plan a strategy to achieve critical mating weight by that date.
- Identify cost-efective strategies to reach critical mating weights. For example:
1. Conservatively stock heifer paddocks and supplement if necessary during the dry season prior to joining.
2. Assess phosphorus status of the heifer paddocks and supplement during the growing season if deficient.
3. Monitor faecal egg counts and drench if required. - Purchase bulls or ensure home-grown bulls have had a Bull Breeding Soundness Examination and are vaccinated against vibriosis and pestivirus or are not a persistently infected animal. If dystocia is an issue, choose bulls with low EBVs for birth weight.
- Perform a risk assessment for all common diseases and vaccinate where necessary.
- Put bulls in either just before the wet season (where it’s difficult to get them out at the start of the joining period) or a month after the green date.
- Over-mate heifers i.e. join more than required and make final selection on foetal ageing results.
- Joining period
- Monitor bulls routinely for sickness, injuries or absenteeism.
- Post-joining
- Pregnancy test heifers about four to five months after the start of the joining period and insist on foetal ageing when the pregnancy diagnosis is performed.
- Select replacement heifers on temperament, then on stage of pregnancy. Attempt to retain as many as possible that conceived early in the joining period.
- Leptospirosis is a potential workplace health and safety issue. If implementing a program, it’s best to vaccinate pregnant replacement heifers at pregnancy diagnosis to ensure good immunity.
- If conception rate of first-calf cows is a major problem, consider a protein meal supplement for heifers during their last trimester of pregnancy. Aim for good nutrition but avoid over fat heifers.
- Calving
- Ensure heifers have shade in their paddock.
- Avoid mustering around calving as this can increase calf loss.
- Avoid handling animals during extremely hot weather.
- Prepare to wean early if seasonal conditions are poor and heifers are losing body condition.
Heifer management calendar
Above is a sample heifer management calendar for the northern tropics. To create your own calendar wheel, download the components HERE.