March 2020 Monthly Management

Spring Feeding Options, Spring Fertiliser Advice, Fertiliser for First Cut Silage, Grass & Grazing

23 March 2020

Spring Feeding Options

Score Hi Maize Dairy Range

The current range of Hi Maize diets with Megalac have been hugely successful among customers for several years now. The range includes crude protein contents of 14%, 17% and 19% to cater for the varying dietary demands throughout the year.

The 17% and 19% are recommended when silage is the main forage source and little or no grazed grass is included in the diet of milking cows. The 14% Hi Maize is formulated to compliment dairy diets when cows are on grass full-time, particularly during the breeding season.

As milk protein is directly influenced by the energy supply in the cow’s diet, the fundamental characteristic of the Hi Maize feed range is its ability to support milk protein output on all forage types. In formulating a quality supplementary feed, the two main sources of energy to consider for dairy cows are the fibre components and optimum starch sources. This feed range contains a high level of maize as the principal ingredient – the best form of digestible starch to feed on a grass-based diet and the most suitable cereal to feed compared to other sources (Barley, wheat, etc..). High quality fibre levels are also included in this range to support rumen function. This also reduces the risk of acidosis and low milk-fat syndrome on low fibre lush spring grass. To further enhance energy content the Hi Maize range contains Megalac to improve milk yield, fertility and body condition score. A premium fertility booster mineral and cal-mag is included to balance nutritional requirements.

Score Super Graze plus Rumbuff & Yeast

Super Graze is a 16% diet (this will drop to 14% when conditions/growth improves) with a high inclusion of maize. It is almost a necessity to have a buffer included in your feed when cows are on full-time grass and growth rates are behind target. This is helpful towards eliminating acidosis/looseness that can lead to digestive complications and a reduction in the milk fat content in the milk. Cal-mag included.

Score Fertility Booster Nut

(this will be available shortly once conditions/growth improves)

An ideal diet for incorporating a fertility booster mineral and cal-mag when feeding levels fall to 2kgs per head per day. Maize based with protein at 14%. Added trace elements ensuring the cows daily requirements are met at lower feeding rates. Trace elements play a vital role in production and fertility during the breeding season. Balanced for 2kg feeding.

cows grazing

Score 16% Dairy Nut

A proven diet that works in all conditions. High inclusion of cereal, including maize and digestible fibre to help maintain rumen function on high quality spring grass. It is particularly useful when grass growth is poor and higher levels of meal feeding are required.

When growth rates increase, ration levels can return to lower levels. Cal-mag included and balanced for 4kg feeding.

Feeding Advice

When ground/growth conditions improve, and the currents levels of high feeding are no longer required it is important that supplementation is reduced gradually. Sudden changes to the diet will cause digestive upsets leading to impaired cow performance that should be avoid at all costs during the breeding season. Care should also be taken not to overestimate the amount of grazed grass in the cow’s diet. Regardless of the feeding regime, having cows on a rising plane of nutrition and improving body condition score leading up the incoming breeding season, will improve submission rates and conception rates.

For further information and advice contact your co- op advisor or nutritionist.

Spring Fertiliser Advice

As all farms have little or no nitrogen (N) out at this stage, it is worth revising the fertiliser plan. If no fertiliser has been spread to date, a recommended application rate of one bag of urea per acre should be applied as soon as possible. If some nitrogen had been applied in January or February, the same rate can be used also. Increasing N application rates now will stimulate grass growth and make up for some of the time lost due to the wet spring – see table below.

Table 1: Recommended rates of N fertiliser (kg/ha) for grassland during the year where approximately half of the farm is cut for first-cut silage and the amount of second-cut is kept to a minimum (0 - 30% of the grassland area)
March April May June July Aug Sept Total N
≤ 85

40 (32)
15 28 15 15
73 (58)
28 35 25 23
111 (89)
29 44 26 26 17 142 (114)
34 53 42 42 31 202 (162)
180 32 32 48 38 38 28 216 (173)
191 31 41 54 37 37 37 237 (190)
200 30 53 53 37 37 37 27 274 (219)
210 31 54 54 56 37 37 37 306 (245)
≥ 210 32 49 55 38 38 38 28 278 (222)

Phosphorus and Sulphur are two key elements in driving spring growth, along with soil pH, nitrogen and the age of the sward.

Spring Phosphorus (P) has the effect of kick-starting grass growth however the P availability to the plant can be lower due to cooler Spring temperatures.

Sulphur (S) is an important nutrient for grassland as it is closely associated with nitrogen uptake and efficiency. As grass grows both Sulphur and Nitrogen are used together so a Sulphur deficiency will decrease nitrogen use efficiency and so reduce yield. Grazing swards deficient in Sulphur require 16 units per acre per year, apply in a little and often approach beginning in Spring. Avoid excess S applications during the growing season, particularly around breeding as it can affect the selenium and copper levels in the grass.

Phosphorus and Sulphur in your second-round fertiliser application will help to push grass growth in late March/ April – a time of the year when any extra growth is always welcome.

Fertiliser for First Cut Silage

Nitrogen - the amount nitrogen required to spread for first cut silage will depend on the age of the sward, the planned cutting date and the grazing history. Recently reseeded swards (0-3 years) will have 25% higher N demand versus older swards. Typically, 100 units of N per acre are required for recently reseeded swards with older swards requiring 80-85 units (depending on cutting date). If nitrogen was applied in early spring, assume that 20% of this remains available for first cut silage.

Phosphorus and Potassium are essential to maximize grass yields, therefore adequate supply of these nutrients in the soil is critical. P and K requirement for a productive crop of silage are 20 units of phosphorous and 100 units of potassium per acre. Cattle slurry can provide a large proportion of P and K requirements at relatively low cost. 1,000 gallons of cattle slurry at 7% DM has a similar N-P-K value as one bag of 5-7- 30 fertiliser. Slurry and chemical fertiliser application should be kept one week apart. First cut silage also requires 16 units of Sulphur per acre. Contact the Drinagh Advisory team for further fertiliser plans and information.

Grass & Grazing

Grass and Grazing is a new section of the management notes where the grazing situation from a different Drinagh milk producer will be profiled each month.

Lawrence Hallihane
The first profile is Lawrence Hallihane from Lickowen, Castltetownsend.
Date 18/03/2020
Average farm cover 734 kg/ha
Yield (litres/cow) 23L
Fat% 4.49
Protein % 3.02
Ration (kg/cow) 3kg
Percentage grazed 55%
Planned start of second round April 10th

Grazing conditions are tough, generally cows are getting out every day for 2 or 3 hours depending on the day and are in by night on silage. Yield per cow dropped in the latest collection due to a combination of factors including low dry matter grass and having a high proportion of silage in the diet. Feed has just been increased from 3kg to 5kg to reduce the amount of silage in the diet when out by day and in at night.

Fertiliser: 70% of the grazing ground got a half a bag of urea and the rest got 2,500 gallons of slurry at the end of January. Planning to go with a full bag of urea per acre as soon as possible.