JUNE 2023 NEWSLETTER

Maintaining grass quality to support milk yield this summer

By Aisling Claffey (B. Agr. Sc, Ph. D, 086 031 7483)

Weather challenges persisted into mid-May and grazing conditions and residuals have suffered as a result, in advance of grass starting to head out in mid-late May and the stem fraction of the plant increasing considerably as a result.

Increasing stem proportions has a number of knock-on effects on production:

Reduced digestible leaf fraction therefore lower protein and sugar intakes
Higher levels of stem naturally act as a barrier to graze outs, affecting subsequent quality also
Affects intake due to the slower passage rate of fibrous material

Maintaining appropriate pre-grazing covers of 1300-1500 kg DM/ha and utilising Pasturebase data to take out paddocks and remove stemmy material from the sward where possible, will help to maintain sward quality and DMI. These bales will prove advantageous in periods of dry weather over the coming months and/or increase fodder reserves this winter.

Many farms will have 5-6 weeks of breeding done at this point and so will be starting to see the effects of IFN_T, the pregnancy hormone. While this is often associated with a drop in milk yield, this drop should be no more than 2.2% per week or 0.5-0.6 ltrs/week depending on herd average. Monitor your herd’s non-return rate, address late-calving and non-cycling cows and focus on maintaining grass quality to support milk yield and solids in the coming weeks.

Hi Phos Dairy 15% Nut

A number of farmers in recent years have observed PICA symptoms, whereby cows are grazing ditches, eating stones, chewing rubber/plastic etc. This is often associated with low fibre in the diet or poor Phosphorous absorption in the animal. Our Hi-Phos Dairy 15% nut has added Di-Calcium Phosphate to support the cow through this period and reduce signs of PICA within the herd. Chat a member of our team if you have any concerns about mineral requirements for your herd!

Start planning your fodder crops for next winter!

By Paul Mooney (B. Agr. Sc, 086 353 2342)

Our damp, mild climate is ideal for growing high yields of fodder brassicas. Yields of 10-12 tonne of dry matter/ha can be achieved on a kale crop sown in June. Provided crop husbandry is good, fodder crops offer considerable savings. These crops can also be beneficial in terms of their ability to breakdown the sod of old pastures in advance of reseeding. This facilitates much easier levelling and seed bed preparation for the new ley and allows more options in the control of perennial weeds.

Kale should be sown from June to mid-July. Broadcast seed at 2-3 kg per acre or direct drill at 0.5-1.5 kg per acre.

Redstart is a Hybrid crop, a cross between kale and rape. This gives some of the yield traits of kale with the rapid growth traits of rape. Sow from July to mid-August. Broadcast 3.5kg of seed per acre.

Fodder Rape is usually sown from August to September. With a good back end to the year and good husbandry, this crop can generate a large bulk of material in a short space of time. Broadcast at 4kg per acre.

Best suited to light stock.
The earlier you sow, the higher the yield will be (1 extra day's growth in July could deliver more than the whole month of October.)
Provide access to a lie-back. (e.g. Stubble field or one in line for reseeding)
Brassicas are highly responsive to Nitrogen and depending on sowing date they can utilize up to 100units of Nitrogen/ac.

Why you should measure the Organic Carbon, CEC and Base Saturation of your soils at least once!

By Aaron Kealy (B. Agr. Sc, 086 199 9148)

Standard soil analysis tells us the soil pH and how much P and K are available. Usually, these results are taken at face value and fertiliser applied accordingly. However, to really get the best out of our soils, there are other factors that should be considered.

Most important of these is the Soil Organic Carbon (SOC). Higher SOC promotes good soil structure and is the basis for soil fertility and is in effect the lynchpin of all agricultural productivity. In the same way crop removal results in the offtake of P and K, carbon is also taken from the soil during this process. If it is not replaced, the carbon cycle will be broken and SOC will dwindle over time, leading to lower productivity – a situation that many farmers now face, but don’t fully know the extent of. As the old saying goes ‘you can’t manage what you don’t measure’. SOC takes years to build up, so a SOC soil test this year will be the start of your journey to improved productivity.

In addition to SOC, Cation exchange Capacity (CEC), which is correlated to soil texture, is an indication of your soils ability to hold and exchange nutrients. Base Saturation (a measure of Macro Elements) is a better predictor of nutrient availability than total nutrient content.

Adding SOC, CEC and Base Saturation to your standard soil test will help you get the best from your soil... Giving us the info to formulate custom blends to suit your soil requirements and maximise productivity.

Winter Fodder Budget

It is critical to assess current fodder reserves in the yard after first cut silage has been made and plan ahead for next winter. Silage reserves are significantly depleted on many farms with buffer feeding observed right through to mid-May on heavier farms. Reduced fertiliser applications and poaching damage throughout the spring will also have reduced production to date on farms.

What is CCN or PEM in calves?

By Joe Naughton (B. Agr. Sc, 086 145 2586)

CCN (Cerebro-cortical necrosis) or PEM (Polioencephalomalcia) is a neurological disease affecting young growing cattle predominantly in the 3-9 month age bracket, whereby ruminal synthesis of Vitamin B1 (thiamine) is impaired resulting in the degradation of brain tissue.

This can occur due to:

Bacterial infection in the rumen producing thiaminase (destroys Vitamin B1/thiamine)
Ruminal acidosis or sulphur toxicity in the rumen can alter the functioning of rumen bacteria resulting in poorer synthesis of Vitamin B1.
Access to high Sulphur water sources or forages. Have you ever completed a herbage mineral analysis to assess plant Sulphur levels? Discuss with your rep if interested!
Bracken/fern poisoning – contains thiaminase

Common symptoms include staggering, dullness, blindness and head movements pushing up and back. You will find calves away from the group in a stressed state. Calves can rapidly go off feed and if left untreated will have convulsions and die. Calves with CCN will need to be quickly rehoused with easy access to water, forage (straw or hay) and meal to try and encourage intakes.

Veterinary advice will be necessary as calves will need to be treated with B1 Vitamins regularly until the animal has recovered. Antibiotics may be necessary for secondary rumen infections due to ulcers. Anti-inflammatories may be beneficial to reduce damage to the brain due to swelling and inflammation in the rumen and intestine if acidosis/scouring occurs, in addition to buffering agents to reduce acidosis pressure.

Here in Ireland, it seems that CCN is most often associated with sub-acute ruminal acidosis (SARA) that occurs when calves have access to lush, fast growing grass containing high levels of sugars and nitrogen with low levels of structural fibre.

If you have any history of CCN on your farm, it's vitally important to consider the grazing management of calves in the 1st grazing season.

Graze heavier covers of grass 1300-1500kgDM/ha (10-15cm) to ensure adequate fibre intake.
Avoid high levels of Nitrogen applications on calf paddocks and excess Sulphur usage.
Make straw available to calves if grazing lush paddocks.
Test water and forages for Sulphur content
Avoid grazing fields with bracken or ferns as higher incidence of CCN in grazing calves where these plants are present.
Supplementing with Grennan’s Early Graze Calf Nuts over summer months at 1-2kgs/head/day. This will assist in reducing the incidence of SARA within your calves

Grennan’s Early Graze calf nuts also contain high levels of live Yeast and Acid Buff to create the optimum rumen environment for bacteria to synthesis Vitamin B1. They also contain a full complement of B Vitamins, most importantly Vitamin B1 to help reduce the risk of CCN.

Importance of mineral supplementation of lambs pre & post weaning

By Damien Conboy (B. Agr. Sc, 087 212 4036)

Overall lamb performance is affected by various factors and mineral nutrition is a crucial aspect. The main minerals that are of concern from a sheep point of view are Calcium, Magnesium, Cobalt, Copper, Iodine and Selenium. However, Cobalt is the most commonly diagnosed mineral deficiency in sheep mainly due to their inability to store cobalt and requirement for daily supplementation.

Cobalt is required by sheep for the synthesis of vitamin B₁₂in the rumen.
Cobalt levels in grass can be particularly low during the summer.
Generally, requirements for lambs are 1mg of cobalt/head/day and 2mg/head/day for adult sheep.
Symptoms of deficiency: loss of body condition, poor fleece quality, ears become dry and scaly (photosensitisation), loss of appetite, runny eyes with tear staining on the face, and raised worm counts (immune suppression).
Sheep farmers experiencing cobalt/B12 deficiency find it difficult to get a finish on lambs and sales are often reduced over the high-risk period for cobalt deficiency (summer).
It is also generally accepted that many flocks lambing in late Feb/March will commence weaning lambs in June/July which puts further stress on lambs. Therefore, it is important to build the mineral and immune status of lambs now.

Creep feed: Lambs that have access to a good quality creep feed (Elite Lamb Pellets) containing Cobalt at 2.5mg/kg should not require any other mineral supplementation as their requirements would be met once their intakes exceed 400g/head/day.

Nugget 4-way sheep buckets contain maximum permitted levels of Cobalt and Zinc, while delivering optimum levels of Selenium and Iodine. This bucket also includes high levels of Vitamin E, D3, A, B1 and B12. Such high levels make them a very good cost-effective way of supplementing Cobalt in a grass-based system as small daily intakes will meet lambs' requirements for both Cobalt, and other minerals and vitamins.