Using Herd Testing to make OAD & Dry-Off decisions
Maximising New Year production while cutting farm working expenses is a delicate balance, especially in the face of dry on-farm conditions. Reducing bought-in feed costs will usually require a corresponding reduction in feed demand. This can be achieved to varying degrees through reducing stock numbers, converting all or part of the herd to Once-a-day (OAD) milking, or drying off less productive animals early.
Look at the data – Not all cows are equal
- The average herd tested cow produced 1.38kgMS per day between January and March 2015
- The bottom 25% of cows produced an average of 1.08kgMS/day during the same period
- Adjusted for liveweight, that means an average cow produced 0.29kgMS/day more than a cow in the bottom 25%
What are some typical options?
- Cull a selection of older, lower PW cows, particularly those with high SCC
- Place part or all of the herd on OAD (beware of initial spikes in BMSCC and cases of clinical mastitis after placing cows on OAD)
- Dry off low LW cows early, along with heifers and low BCS cows
Consider the potential gains:
- Feeding the remaining (better producing) milking cows more provides an opportunity to yield more production, giving greater bang for your feed buck
- Alternatively, reduced feed intake of dried off animals can be ‘banked’ in the form of savings on supplements
- Switching part of the herd to OAD, or drying some off completely will deliver operational savings through less milkings and/or fewer cows to milk
- OAD milking can help maintain body condition score and extend lactation, setting the farm up to maximise days in milk from autumn growth
- Better cow condition can be achieved by a move to OAD or dry off, setting cows in good stead for the reproductive period and season ahead, and reducing the need for winter supplement to recondition cows over the dry period
- Less milking naturally means less pressure on (and less need for) staff
- Less time in the milking shed generally means less stress for staff and cows
What tools are available?
- Milk On vs Dry-Off Calculator - This newly developed calculator from Dairy NZ will be available on the Dairy NZ website from 1 February 2016. It is recommended that farmers use this with support from trained users such as DNZ consulting officers, farm consultants and some veterinarians. It evaluates the financial merit of potential culling, OAD and dry-off decisions, given available pasture and supplements. The effects of making these management changes on different dates can be analysed relative to desired BCS and pasture covers at a fixed PSC.
- MINDApro – Drying Off Guide
- Located in MINDApro under Reports > Management Reports, the Drying Off Guide allows a range of criteria to be selected and thresholds to be specified. Wherever an animal meets a criteria/threshold, they will be highlighted in the report. Try sorting by ‘Criteria Met > Descending’ to identify the animals that meet the most drying off criteria
- MINDA Milk – Animal Detail
- Use the Animal Detail tab in MINDA Milk (located at minda.co.nz) to hone in on low LW (Lactation Worth) animals. If your herd’s LWs have been informed by herd testing in the current season, they will be a good indicator of which cows are struggling to convert feed to profit this season, and may be candidates for early dry off or a move to OAD
- Clean, query free records
- These will help generate a reliable and well-informed Drying Off Guide. The LIC Customer Experience Centre (0800 2 MINDA) and Field Assist team can support you with this
Good decisions require good information
- Regardless of what decisions get made to alleviate feed demand, data around the performance of individual animals is essential to maximising herd productivity and profitability
- Criteria such as production, LW and SCC are important in making OAD and dry off decisions, and can be derived from your herd test data. It’s important to ensure that the information you’re making decisions on is complete and up to date so regular herd testing is key
- Remember, switching to OAD can result in SCC spikes and increased mastitis cases. Knowing who your at risk cows are with recent Herd Test information is key to managing BMSCC