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Steps for dealing with working Immediate actions Next priorities Develop a flexible feed plan Monitor Stock Health Reduced milking frequency Body Condition Score Loss Factors that will affect BCS loss Managing SCC Downloadable documents

Heavy snow can be tough on farming families and staff, both physically and emotionally. When snow hits during early lactation, ensure the safety of your family, staff, and livestock. Move animals to safe areas with shelter and water, and ensure they can't wander. Check power, phones, and neighbours. Use generators to keep essential equipment running and monitor local radio for updates. Prioritise moving stock to appropriate areas, feeding them carefully, and ensuring they have clean water. Separate weaker animals for special care. Check access routes and communicate with neighbours and dairy companies. Adjust feeding plans and monitor stock health, especially when introducing new feeds. Consider reduced milking frequencies if needed and always monitor body condition scores and somatic cell counts.

Steps for dealing with working in heavy snow:

Bouts of heavy snow are hard physically and emotionally on farming families and staff as they worked in freezing conditions. Use the information below to deal with snow in early lactation.

Immediate actions:

  • Ensure safety of family and staff
  • Move stock to safety, shelter and water - preferably lighter land or a stand-off area. Break ice on troughs
  • Make sure stock can't wander. Don't rely on mains powered electric fences
  • Check power and phones. Report outages if possible. Check neighbours - is it just your power/phone?
  • Check dogs, poultry & pets
  • Are neighbours ok, or can they help you?
  • Use generators if available to keep pumps, electric fences and essential household appliances running. Source generators if you don't have them.
  • Monitor the local radio for news and information.

Next priorities:

  • Move stock to a stand-off or sacrifice area if they are not already on one. Ensure they have enough space to lie down - at least 3.5 sq.m per cow if on woodchip, sand or concrete for up to two days; at least 5 sq. m on woodchip or sand for more than two days; and 8 sq.m if on crops or sacrifice paddock.
  • Feedstock. They will be hungry and will eat whatever is put in front of them, so take great care when introducing different feeds
  • Ensure stock has access to ample clean water
  • Separate out any small, weak, sick, lame animals and put them in a separate mob for special attention. Provide shelter and additional feed if possible
  • Prioritise actions - if animals are down on the ground it may be better to humanely destroy them, for others seek advice
  • Check and clear driveways and access tracks. Report road and tanker track access problems to council and/or dairy company if appropriate.
  • Look after family and staff, check neighbours. Accept help if you need it and give it where you can. Communication is critical
  • Milk any lactating cows, but note that you may choose to delay milking or milk once a day to allow you time for other priorities. Monitor SCCs and watch for mastitis, and keep in touch with the dairy company as necessary
  • Watch the weather forecast like a hawk and be prepared to react.

Develop a flexible feed plan

Feeding to manage animal stress and to maintain as much condition as possible is critical in a snow situation. On most farms, at present, the major problem will largely be a feed one with most farms nearing the end of their first round.

Changing Feeds

Beware of introducing a different feed type too quickly. Changing from mainly pasture to high carbohydrate supplements like cereals can cause rapid changes in rumen fermentation and there is a risk of developing acidosis, sometimes called "grain overload", which can kill cows.

Slowly introduce similar feeds first

If your herd was on pasture, introduce pasture-based supplements first - hay, grass silage.

Gradually add others

Start with 2-3kg of grain or other supplements per day and very gradually increase the amount as necessary over at least two weeks. It may be possible to graze deteriorating (but not rotting) pastures after snow disappear, and this will allow quicker regrowth while providing some dilution of high carbohydrate supplements.

Low-risk feeds include:

  • Hay
  • PKE

High-risk feeds include:

  • Molasses
  • Vegetable starches (tapioca, potatoes, carrots)
  • Wheat
  • Barley
  • Oats
  • Maize
  • Silages (some fibre present)
  • Broll

Maintain Ca & Mg intakes

Keep up calcium and magnesium supplements. Magnesium is especially important early in lactation when cows are vulnerable to ketosis, particularly if they are underfed.

Monitor Stock Health

Animals will quickly get stressed when they have to deal with the physical effects of a heavy snowstorm. Ensure that they are monitored throughout the event.

  • Cold, wet stock will lose condition quickly. Provide shelter, adequate feed and water.
  • Aim to minimise CS loss over the next 3 weeks as this will minimise the impact on reproductive performance.
  • Monitor residuals to ensure intakes are being achieved. Colostrum cows aim for 1500 kg DM/ha; milkers target no less than 1400kg DM/ha but minimise pugging damage using on-off grazing.
  • Restrict the dries, especially the late calving cows up to 50% of their target energy requirements (no less than 5 kg DM/dry cow)
  • Consider standing cows on a sacrifice area, cow yards or wintering pads (preferably with shelter and not by the road) during the day and allow them to graze at night. Cows can consume their daily intake in 6-8 hours.
  • Watch for cow space
  • A 400 cow yard would only accommodate 200 cows as a standoff area
  • Cows need to lie for at least 8 hours a day. If lying is restricted they will lie in preference to grazing when put onto pasture, resulting in underfeeding.
  • Cows don't like lying on concrete so try and minimise the amount of time they are stood off on yards.
  • Milkers must be offered a minimum of 10 kg DM/cow Friesians and 8 kg DM/cow Jerseys. These feeding levels will reduce subsequent milk production. The extent of the carry over effect on milk production from underfeeding depends on the length of time cows are restricted. The longer the period of underfeeding, the greater the loss
  • Feed quality is paramount - don't feed mouldy hay/baleage to pregnant or lactating stock.
  • Magnesium supplementation is good insurance, especially if feed is restricted. Use 70-100g magnesium oxide dusted on feed or 50g of magnesium chloride or sulphate through water, however water intake will be lower in cold, wet conditions.
  • Watch for bloat and nitrate poisoning when starting stock back on kale - feed a fibre source first
  • Remove any cows that abort from the main mob in case it is contagious.

Missed milkings through power loss

Power cuts will probably mean that some milkings will be missed, but cows are resilient. DairyNZ research has shown that delays of up to a week can be tolerated by mid-lactation herds, and with careful handling, they can return to full or near-full milk production...read more

Reduced milking frequency

OAD Milking

Once A Day (OAD) milking is an option to reduce pressure on the staff but it comes at the cost of reducing the potential milk production for the season. OAD cows in early lactation will consume the same amount of feed as TAD milked cows, therefore this should not be seen as a strategy to save the feed.

3 times in 2 days (16-hour milking)

For high-producing herds (>1.7 kg MS/cow/day) 16 hours or 3 milkings in 2 days may be a better option than OAD milking. Recent research is not available on the impact of this milking regime on subsequent milk production however farmer experience would suggest that carryover effects are less than those experienced with OAD milking.

Read more on milking intervals

Body Condition Score Loss

The BCS in which a cow calves, the amount of BCS she loses post calving and the BCS she falls to before starting to gain condition (nadir BCS) are all associated with milk production, reproduction and health.

Cows that lose the most condition in early lactation OR are the thinnest at mating are less likely to be submitted for AI and less likely to become pregnant.

4 to 5% less pregnant at 6 weeks and 3 to 4% less pregnant at 12 weeks if:

  • Cows lose 2.0 BCS units instead of 1 post calving
  • Cows are a 3.5 at mating rather than a 4.5

In comparison, cows that are gaining live weight before mating are more likely to get pregnant, however, this effect is small:

  • 2% more pregnant in 6 weeks and 1% more pregnant in 12 weeks if cows gain 0.2 kg Lwt/day compared with losing 0.2 kg Lwt/day.

Feeding to minimise BCS loss prior to mating is therefore a higher priority than feeding cows well during the mating period.

Factors that will affect BCS loss in early lactation

Genotype and breed of cow

Increased overseas genetics in the herd results in increased BCS loss in early lactation, especially in pasture-only systems.

Supplementary feeds

Most research shows no linkage between supplementary feeds (grain, molasses) and improved BCS in early lactation or fertility in dairy cows. Supplementing cows with 3 or 6 kg DM of concentrates did nothing to the amount of BCS lost during the first 6 weeks of lactation

Supplementing cows with energy supplements from around 6 weeks after calving can increase the rate of BCS gain and may improve fertility in cows that would otherwise be underfed.

OAD milking

Milking cow's OAD in early lactation does little to alleviate BCS loss early lactation, but it improves the rate of live weight gain after 6 weeks in milk.

Managing SCC

Expect high somatic cell counts (SCC) and clinicals

Due to missed milkings or a short-term move to OAD farmers should expect big fluctuations in SCC and the likelihood of increased clinicals. Farmers can expect their bulk tank SCC to potentially double from their pre-snow levels.

Downloadable documents

Last updated: Aug 2023

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