Autumn calving

To autumn calve, or not

By Cheyenne Nicholson

Dairy Trust Taranaki are gearing up to reveal the results of a trial comparing transitioning from one calving system to another.

Dairy Trust Taranaki will be revealing preliminary results of their autumn calving trial this month at an open day on their Kavanagh farm in Hawera.

Operations manager Debbie

McCallum says that the trial aims to identify implications of the transition period required to change the season of calving and compare an autumn calving system with a spring calving system.

Many farmers are opting for wholeherd autumn calving or split calving to mitigate the risks of summer dry and capitalise on the greater winter pasture growth the region has been seeing for the past decade.

“Autumn calving has become popular along coastal Taranaki,” McCallum says.

“Summer dry is common. More often than not there’s a big soil moisture deficit. Low pasture growth rates in summer and autumn along, with Debbie McCallum from the Dairy Trust Taranaki and Jake Jarman on one of the increased pasture growth rates over Trust farms where he had been researching the transition process to autumn winter make it a viable option for coastal calving for his thesis. farmers.

“There’s a bit of a lifestyle perk about it, too. Rather than battle through milking weren’t mated, but instead entered into increased BCS and a subsequently in summer, many would rather milk in an extended lactation through to the higher risk of metabolic issues and winter and have a break over the January following winter and mated in winter higher reproductive performance for a through March period.” 2018. season.

Calving in March and April when the During this extended lactation, the By doing a whole-herd transition weather is better is appealing for many autumn-calving cows averaged 661kg utilising an extended lactation, farmers with calf rearing easier in the dry, warmer MS/cow and 488 days in milk. Some cows can maintain their existing herd. On the weather. competed 577 days in milk, and 50% downside, there will likely be cows who

In 2017 the original 600-cow herd of the herd were still milking at drying are unsuited for extended lactations, residing at Kavanagh farm were split off. During the first autumn-calving which can lead to cows gaining aboveinto an official autumn-calving herd lactation, the milk production curve optimal body condition score post 300 and a spring-calving herd. The herd was flattened out and while they didn’t peak days in-milk. randomised on age, BW, PW, liveweight, as high as the spring herd, they displayed “We found a fairly notable increase in previous production and calving date to greater persistence. BCS in the transition cows. They packed create two equal herds for ease of data “One of the biggest drawbacks is on the pounds. They’re being fed as a comparison. that loss of production in that second normal-producing in-milk cow, but their

The farm was also split into two lactation. Per cow, production was actual milk production drops so that farmlets, randomised into location, soil negatively affected. This would be extra energy goes into body fat,” she says. fertility and distance from the shed. something for farmers to consider as it’s “We had some big variations in the

The first 18 months of the trial was a financial cost,” she says. herd, which indicates that we had some dedicated to the new autumn-calving This hard-and-fast transition process cows who were very well suited to herd transition from spring to autumn comes with pros and cons. extended lactations as their production calving. The first spring the autumn cows The two notable implications are was fairly good, and others who weren’t.”

“Some farmers are saying they don’t care if they break even, or even if it costs a bit more, as it’s worth it for the lifestyle aspect.”

Debbie McCallum

The biggest issue here is metabolic. To combat this, cows were given a restricted intake to help them mobilise body fat to minimise metabolic issues.

The autumn-calving herd displayed higher reproductive performance during the extended lactation, but not their first lactation calving in autumn. A high sixweek in-calf rate meant that the calving pattern was condensed, which put pressure on feed demand.

“This was largely expected due to the longer interval between calving and mating, and once the autumn-calving herd returned to a short interval, their reproductive performance got back on par with the spring herd,” she says.

The autumn-calving herd had a 16% better three-week submission rate, 16% better six-week in-calf rate and 8% better not-in calf rate than the spring herd in that first lactation.

While there are undoubtedly many benefits being noted from the trial, there are also some points to consider when thinking of making the switch. Many farms will need a higher input of nitrogen to support winter milking along with top-notch pasture management, laneways need to be good quality to reduce lameness issues and mating through winter can be tricky due to fewer daylight hours.

“Difficulty getting cows in calf over Dairy Trust Taranaki was formed merging three legacy entities; the Stratford demonstration farm, Waimate West Demonstration farm and Taranaki Agricultural Research Station.

winter was a trend this year, we didn’t have a very good empty rate,” she says.

“From a practical perspective having a good amount of feed on hand is important. “Dry cow management also becomes a whole different kettle of fish as you’re battling with facial eczema and ryegrass staggers at that time of year, too.”

Economic analysis of autumn calving will be done over the coming years, as the trial gets a few more lactations under its belt and will be a large part of Dairy Trust Taranaki work in the future. While the economics of autumn calving is important to a farm’s bottom line, there are other goals and values to consider.

“Some farmers are saying they don’t care if they break even, or even if it costs a bit more, as it’s worth it for the lifestyle aspect. Calving and calf-rearing in warmer weather is more pleasant, and many farmers get more enjoyment out of their farm,” she says.

“You do spend more on feed over that winter period, but you feed little over summer on the flipside of that.

“What we have seen overall is an increase per cow and per ha production for autumn compared to spring, and that’s likely due to a good number of days in milk compared to spring.

“We will have more results and statistics to share at our open day and, of course, over the coming years of the trial, to put some meaningful data in front of farmers to consider.” n

MORE:

Dairy Trust Taranaki will host an open farm at their Kavanagh farm on February 10, to discuss their findings to date. For more information, head to their website or Facebook page.

Dairy Trust Taranaki are partway through an autumn calving trial on their Hawera farm, investigating the economics of autumn calving.

One metabolic disease can increase the risk of other metabolic and infectious diseases and reduce milk production, health and reproduction.

The big three

By Cheyenne Nicholson

Metabolic diseases in the transition and early lactation stages can affect cow performance unless it is treated and managed carefully.

Good management through any changes slowly, the typical rule of bloodstream indicate that fat breakdown the transition period can thumb is the rumen takes about 14 days is occurring at a greater rate than the minimise metabolic issues to adapt to feed changes. cow can cope with. Ketosis will usually and maximise production and Ketosis, magnesium deficiency and present as rapid weight loss, reduced reproductive performance. milk fever round out the big three in milk production, a dry, rough coat and

Massey University associate professor metabolic disease of both transition and dry manure. Some cows will show off Dr Jenny Weston says poor transition early lactation cows. behaviour like aggression, chewing on management can result in decreased metal piping and rails, high stepping and herd performance and it can be hard Ketosis a wobbly gait. to regain that ground lost. One of the Ketosis is a condition of energy deficit. Overfat cows and high-producing cows key things is setting up the cow for Cows will always lose some weight post- are more susceptible to ketosis as their going from a lower level of maintenance calving due to a mismatch between energy needs are greater. As with most feeding to eating at capacity to fulfil the feed supplied to meet requirements and diseases, the number of clinical cases demands when she’s back in the milking what the cow can physically eat. Ketosis is just the tip of the iceberg. For every shed. is a step beyond this. When fat is broken one clinical case, there will be around

“It’s as if someone’s been on a strict down the waste products or metabolites 10 sub-clinical cases. Subclinical ketosis diet for a long period of time and their – ketone bodies or non-esterified fatty can affect the function of the ovary after stomach has shrunk somewhat and you acids – associated with this process are calving, which can contribute to nonsuddenly go ‘Here’s an all you can eat used by the body. When the cow is in cycling cows. buffet, go for it’. They are less able to cope a negative energy balance, she will use Preparing the cow for higher feeding with eating everything you put in front of more fat to provide energy to maintain levels and a change in diet composition them,” Weston says. health and production. is critical to preventing ketosis. Attention

However, this doesn’t happen “This excessive breakdown of fat to detail when it comes to mineral overnight as the rumen needs time overwhelms the metabolic pathways balance is also important along with to adapt to the dietary changes. Plan and causes a backlog of metabolites that avoiding having overfat cows at calving to be increasing feeding levels during accumulate in the blood system,” she and assessing if feed is supplying transition to build their intake back up says. sufficient energy. The key strategy for and consider what is in the diet. Make Excess ketone bodies in the treating ketosis is to boost their energy

“It’s hard to predict which ones are going to recover and which ones are going to stay down. Often, they just stand up and walk off after treatment, other times they don’t.” Dr Jenny Weston

through either oral supplementation with propylene glycol or dextrose given in the vein. A vet may administer an injection of corticosteroid to encourage the cow’s metabolism to boost glucose production. Reducing energy demands, for example, dropping to once-a-day milking can be effective also.

Magnesium deficiency

Cows don’t store enough magnesium (Mg) in the body, so it needs to be supplemented daily. Cows often aren’t efficient at absorbing Mg during times of stress – like drying off, feed shortages and bad weather – and their ability to absorb Mg decreases as they get older.

Clinical symptoms of Mg deficiency will be familiar to most farmers. The uncoordinated stagger of overstimulated muscles is distinctive. Aggressive behaviour, fast heart rate, twitching and, in severe cases, convulsion and down cows can occur. Subclinical symptoms are more subtle – reduced appetite, reduced milk production, kicking cups off and flicking their tail.

“Treatment can be frustrating, so prevention really is critical. Ensuring cows are supplemented with Mg every day is key. The form of Mg will depend on what sort of system each farm has,” he says.

Avoiding feed with high levels of potassium and nitrogen is important as these reduce the absorption of Mg. When it comes to treatment a range of products are around to elevate Mg in the blood, but improvement involves getting enough Mg into the fluid around the brain, which is difficult to achieve.

“It’s hard to predict which ones are going to recover and which ones are going to stay down. Often, they just stand up and walk off after treatment, other times they don’t,” she says.

Milk fever

Milk fever is low blood calcium (Ca). Ca is required for muscle contraction and is stored in the body (in the bones). Ca levels are regulated by the body and when the diet is low in Ca, efficiency of absorption from the gut will increase and the amount lost through excretion will be decreased. It will also be mobilised from the bone during times of high demand, however, this process is not instantaneous and many cows will go down or die before the body has a chance to right itself.

“If you continue to feed high levels of Ca pre-calving, you lull the cow into a false sense of security. Then she calves and starts lactation, Ca demand increases and she can’t keep up,” she says.

Nearly all cows will go into a subclinical phase of low Ca that is considered to be normal immediately post-calving. It’s the cows whose blood Ca drops even further that will progress to clinical cases.

Many symptoms of milk fever are the opposite of Mg Staggers. The early stages are often seen as an odd gait and overly excitable cows. Muscles are affected so cows can’t stand, and this can progress onto not being able to lift their head. The heart muscle becomes weak and it can’t pump as much blood around. The muscles in the gut then stop working, resulting in bloat as the rumen stops moving and gas cannot eructate.

Intravenous milk fever treatments act quickly, but any product that contains Ca or Mg carries a slight risk when being administered into the vein.

“Both can affect muscle contraction and stop the heart, and occasionally a cow dies while treating them. Under the skin treatments are slower to act, especially on a cold day. Typically, I’d advise only severe cases to be treated via the vein, with mild cases it’s best to err on the side of caution,” she says.

Cows do not store enough magnesium (Mg) in the body so it needs to be supplemented daily.

Getting enough Ca into a cows system to keep them going for 12-24 hours is important to give the body time to enable Ca mobilisation from bone. Oral treatments are also available but should only be used in mild cases as severe cases affect swallow reflex.

Getting a vet to show everyone onfarm how to give metabolic solutions in the vein is important, as is keeping metabolic solutions in flexi packs on the quad or ute for instant access. n

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One last word …

Back in January 2018, I wrote a column about a drought gripping parts of the country. By January 2019, the weather had done a complete 180 and farmers had grass coming out of their ears and were busy making supplementary feed to restock the hay sheds and silage pits.

This time last year, some regions were experiencing another severe drought.

Hot and dry conditions had caused pasture growth to stall and paddocks frizzled away to dirt. Crops were basically non-existent. The lack of rain and soil moisture saw farmers dip into their feed reserves, dry off stock – some as early as

December – or switch to once-a-day or 16-hour milking, while others sent stock to the works or at least tried to with processors coming under huge pressure.

Farmers from all over the country rallied to help those most affected and donated feed.

Not so this year.

Mother Nature has come to the party and given farmers perfect conditions, and now many are well into making supplementary feed. Some farmers are telling me they are on their third or fourth cut. They have grass coming out their ears once again, and not enough mouths to keep up.

The number of tractors, balers and machinery and trucks on the road has certainly increased over the past few months and does not seem to be slowing down. I have been told some of the maize crops around Waikato are phenomenal and driving around Manawatu and Tararua, I have seen a number of paddocks that have been a sea of wrapped bales.

I know many farmers who treat this time of the year as a big social event where everyone pitches in to help cart and stack, finishing with a barbeque. As one farmer put it, “It is the best time of the year.

One of my old farming friends tells me that he spent “bugger all” last year on harvesting costs because there was nothing to harvest.

No one is really too stressed, the sun is shining, the grass is growing and the kids are on holiday, meaning this is something we can do as a family and with friends and neighbours. We all pitch in and help each other out.”

One of my old farming friends tells me that he spent “bugger all” last year on harvesting costs because there was nothing to harvest. This year, he has spent all of what he saved and probably even more than what he budgeted for this season, but hopes he won’t need to buy any feed in. He reckons he will have enough feed to get through even if he runs into a dry spell.

Pastures were just starting to dry out in early January when Mother Nature delivered the rain.

And the good news keeps coming with rises in the first two Global Dairy Trade auctions this year showing that global demand is high, leading to banks and other outlets to lift their payout forecast to between $7/kg MS and $7.20/kg MS.

My farming friend says he expects to do record production thanks to the perfect summer conditions and is on cloud nine.

“I have a hay barn and silage pit full of insurance and is as good as money in the bank and if the payout goes up, I will be a very happy man,” he says.

Thanks to Arohaina Le Comte who sent us the picture of the Ninja Turtle-themed bales. She and her husband have been farming for 20 years and were on their way to Christchurch when they passed these creative and colourful characters on the outskirts of Ashburton on State Highway 1.

“I thought that I would share this with the farming community. (When I saw it, I) thought, ‘What an innovative way to use silage bales’. Cowabunga, dudes.”

Cowabunga indeed. Sonita

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Dairy Diary S February 2021 M T W T F S February 2021 1 2 3 4 5 February 2 – DairyNZ Tiller Talk Manawatu hosts a specialist pasture group. Topics will include forage value index, regrassing, summer supplements and analysis on cost, and benefit to business 6 13 7 14 8 15 9 16 10 17 11 18 12 19 and winter crops. Info at www.dairyevents.co.nz 20 21 22 23 24 25 26 February 4 – Lincoln University Lincoln University Dairy Demonstration Farm (LUDF) 27 28 29 30 31 Focus Day is aimed at dairy farmers and dairy industry professionals. Come along and hear about season to-date performance, and research and development updates. February 16 – Smash Info at http://www.siddc.org.nz/lu-dairy-farm/ Positive Planning For the Future, Invercargill. Topics include keeping a lid on costs, breeding to fit your goals and February 9 – DairyNZ succession planning. Lower North Island rural professional’s Know Your Numbers Info at www.smallerherds.co.nz workshop. Network and exchange ideas on how to achieve better outcomes for our farmers. February 17 – Dairy Women’s Network Registration essential. Info at www.dairyevents.co.nz Join us for a practical on-farm workshop about body condition scoring in Kaihere, Hauraki Plains. We’ll be out in February 10 – DairyNZ a paddock with Ilyse Jennens from Franklin Vets (DairyNZ Reach your goals faster with DairyNZ’s Biz Start event in accredited) as she shows us how to condition score cows. Ashburton. This standalone event is part of our Biz Start Info at www.dwn.co.nz/events series and packed full of great information about business structures, taxation and budgeting. February 23 – DairyNZ Info at www.dairyevents.co.nz Succeed in business group is a forum for like-minded farmers, developed for those who want to enhance their February 10 - SMASH skills and career options. A series of five events covering: Weighing Up Your Options, Karamea. Darren and Jennifer goal setting, contracts, running an efficient office, budgets Hislop will host this field day, where they will be looking and cashflows, compliance and self-employment. into some of the features of their farm, including their new Info at www.dairyevents.co.nz effluent and in-shed feeding systems. Info at www.smallerherds.co.nz February – Dairy Women’s Network Your farm business future, various dates and locations. February 11 – DairyNZ ASB and NZ CA Limited workshop focused on succession Reach your goals faster with DairyNZ’s Biz Start event in planning and preparing the next generation into farming Glenavy. It will focus on the various business structures, and farm ownership. considerations around taxation and personal and cashflow Info at www.dwn.co.nz/events budgeting. Info at www.dairyevents.co.nz March – Dairy Women’s Network Make time for your people, various dates and locations. Free February 11 – DairyNZ workshop and webinar series funded by New Zealand Dairy Farmers and rural professionals are welcome to sign- Farmers through the DairyNZ levy. up for the Good Yarn event in Manawatu. Good Yarn is Attendees will gain knowledge about employment a hands-on workshop that will give you the practical contracts and rosters, salary packages, accommodation tools and confidence to be able to talk to people in rural requirements, as well as growth opportunities, wellbeing communities about mental health. and building strong team relationships. Info at www.dairyevents.co.nz Info at www.dwn.co.nz/events