Looking beyond the long Irish lockdown

BUSINESS METHANE RESEARCH

Katie Starsmore and Jacob Sievwright.

Beyond the long Irish lockdown

Words by: Katie Starsmore and Jacob Sievwright

It’s finally starting to warm up here in Ireland and Covid-19 restrictions are looking to be lifted in the coming months. It’s been a long time coming! At the end of March/early April we had a few weeks of cold frosty mornings which stunted grass growth. Following that we have had lots of warm dry weather and haven’t had much rain over April so we are currently praying for the rain. Who would’ve thought you would ever say that in Ireland? We’re now in the full swing of breeding with plenty to keep an eye on. Our mating start date (MSD) is May 1 and we plan to artificial insemination (AI) for 11 weeks while using 8 teaser bulls on rotation within 300 cows. Each of the teaser bulls is fitted with a halter that has a chin ball. The chin ball marks on the cows along with tail paint that we use to identify bulling cows. Tail paint is topped up twice a week and any cows seen to be bulling are written on a

whiteboard at the front of the herringbone pit to be drafted for AI.

Cows are inseminated by Munster Bovine AI technicians around 10am every morning and only conventional semen is used. The first eight weeks of mating dairy semen is used, however the following three weeks of mating beef semen is only used. Our target is to have 95% of the cows served to AI within the first 24 days of mating.

Leading up to mating we check for premating heats for three weeks before MSD. Any cows that had a heat in the week prior to MSD will receive 2ml of prostaglandin (PG) seven days after the recorded pre-mating heat to bring them forward to make a more compact calving. On May 18 (Day 18 of mating) all cows that haven’t cycled are scanned for any cysts, metritis or other issues that would be causing them not to cycle. Also cows that had a difficult calving, had twins, retained placenta, or were sick/down during the calving season are metri-checked. This means that any infection or endometritis can be identified and treated to increase their chances of cycling and holding a pregnancy.

Any cows that haven’t visibly come into heat by the end of the fourth week of mating will be synchronised using the CIDR program. Also, any late calvers (calved after April 1) as well as any cow that has lost 0.5 of a condition score since the start of the year are milked once a day until breeding to increase the likelihood of starting to cycle faster. The goal is to have all cows served by the end of the fourth week of mating.

We also carry out pregnancy scanning numerous times during the mating season to ensure we are able to have the highest in-calf rate possible. Cows that were served in the first week of mating are then scanned on June 7.

Cows that were served in the second week of mating are then scanned on June 14. This identifies if the cows have held the pregnancy or not. Any cows that are confirmed not in calf by July 1 are synchronised for the one last serve before the mating end date of 16th July. We are trying to minimise any issues before and during mating that would lead to a decreased fertility for each cow.

The dairy mating season has begun. Katie Starsmore and Jacob Sievwright plan to AI for 11 weeks.

METHANE EMISSIONS TRIAL

Katie recently finished a trial measuring methane emissions from early lactation cows with two different diets; grass only and grass with 3kg silage per day. This trial began as soon as cows calved and they were out at grass which was within the first week of February.

The trial followed the cows every day since and she has methane emission values for each cow over this period. There were a total of 80 cows in this trial and they will continue to be measured for residual effects of the different feeding strategies until the end of June. The importance of this research is the effect that different farm strategies have on methane emissions in early spring. As the winters are relatively wet and cold, cows are housed inside during the winter which means there is little grass growth over this period. That means different farms across the country will have different amounts of grass onfarm and may need to supplement silage if there isn’t enough. That’s where this research will come in, milk production, grass production and methane production are all considered and they will know the impact of it all.

Katie also started another trial in the middle of April which is testing another feed additive.

This feed additive will be trialled for 10 weeks and if there is a response with either methane reduction or milk production increase, there could be scope to increase the trial length to a full lactation in future years. At the beginning of this trial, there needed to be individual intakes for each grazing animal taken. The way they did this was to orally dose the cows with an alkane bolus for 11 days and on day seven of the dosing, faeces for each cow was collected before each morning and afternoon milking for the remaining five days. So that means Katie has to be at work for 5.30am to collect these samples every day for a week. Once this is done a 20g faeces sample is then taken into an individual cup for each cow which is then frozen until all 10 samples for each cow are taken during the week. The faeces will be analysed for alkane content to estimate the amount of kgDM eaten per cow. This will also be done at the end of the 10 week study to investigate if the feed additive has an effect on intake as well as methane and milk production.

Testing times: Katie Starsmore is using faecal samples from cows to test a new feed additive.

• Katie Starsmore and Jacob Sievwright are expat New Zealanders working in dairy in Ireland. They were profiled in Dairy

Exporter, February 2021. The couple will be contributing a regular Milking Platform column for the Dairy exporter. • www.nzfarmlife.co.nz/kiwi-skills-soughtafter-in-ireland