We are now in mid-September, and the very poor weather of the last six weeks is uppermost in the minds of all farmers.
Many dairy herds have had to be fully or partly housed in recent weeks. A proportion of the good quality first and second cut silage made earlier in the year has already been consumed on numerous farms. Some third and indeed second cuts are still to be ensiled on farms in northern and western counties.
The winter fodder situation may yet still be affected by the weather and ground conditions over the next four to six weeks. Last year, there was significant silage harvested in the first week of October, following settled weather.
Farmers will benefit from completing a fodder supply calculation to check silage stocks against requirements within the next six weeks. An online calculator is available through DAERA Online Services to help with the calculations. For those who wish to do the calculations by hand, a worked example is given below.
For example a silo measuring 35 meters long by 12 meters wide with an average silage depth of 2.5 meters has a silage volume of 1,050 cubic metres (35 x 12 x 2.5).
To convert cubic meters of silage to tonnes of fresh weight the calculated volume is multiplied by the appropriate conversion factor from Table 1 below. Assuming the silage analysis has shown a Dry Matter of 25%, multiply the volume of 1,050m³ by 0.68 to get 714 tonnes fresh weight of silage in the pit.
|Silage dry matter (%)||Tonnes of silage per cubic meter|
|20||Multiply by 0.77|
|25||Multiply by 0.68|
|30||Multiply by 0.60|
|35||Multiply by 0.54|
|40||Multiply by 0.48|
|45||Multiply by 0.42|
|Wholecrop 40% dry matter||Multiply by 0.67|
|Forage maize 30% dry matter||Multiply by 0.75|
Once you have calculated how much silage you have, the next step is to calculate how much silage is needed. Table 2 below shows average silage requirements for a number of categories of dairy livestock.
|Dairy livestock category||Silage required per month (tonnes)|
|Heifers 1 to 2 years old||0.8|
|Heifers 0 to 1 year old||0.6|
To calculate the silage required, simply multiply the number of cattle to be fed by their monthly silage requirement and the number of months the animals are likely to be housed.
On completion of this calculation, for all stock on farm, you can compare the silage requirements with silage stocks. It is better to know if you are going to need additional forage early in the winter to secure additional supply before you actually need it, as prices will inevitably rise through the winter if there is a fodder shortage.
It is worth bearing in mind while doing your calculations that with many farms having made drier than normal first cuts back in early May, cows may eat more of this silage than in previous years.
It is very important in any winter feed plan to get your forages analysed. This will give you a prediction of the silage intake potential, metabolisable energy (ME), crude protein, and dry matter content of the forage.
While it is important to get an initial silage sample analysed, you should also remember to get subsequent, representative samples analysed during the winter, as silage quality will vary through the pit.
Concentrate feed efficiency
Milk prices have improved and are at a level where many farmers will be encouraged to increase concentrate feeding. However, as concentrates are the single biggest cost in milk production, it is important they are allocated to cows that will give the greatest response. Irrespective of the feeding system, whether it is Total Mixed Ration (TMR), out of parlour feeding, in parlour feeding, or a combination of all three, it is important that you know the milk production potential of your forage (M+). This will allow you to more accurately allocate concentrates.
Ways to improve concentrate feed efficiency:
- formulate a feed plan based on accurate forage analysis
- calibrate in parlour and out of parlour feeders regularly
- if feeding a forage wagon diet, group cows according to yield and stage of lactation
- formulate forage wagon rations to meet the requirements of the lowest yielding cow in the group
- feed parlour or out-of-parlour concentrates to yield above the forage wagon diet or forage M+ figure at a rate of 0.45kg concentrate/litre
- early lactation cows should have concentrate allocated on a gradual build up over 21 days with cows then lead fed to day 80-100 of lactation
- first lactation heifers cannot eat as much forage as the mature cows and thus should be expected to produce 3-4 litres less than the M+ figure for the forage or forage wagon ration.
Hopefully, weather conditions will improve through the remainder of the autumn allowing cows to be grazed and any remaining silage crops to be ensiled. However, fodder stocks may still continue to be an issue on some farms making fodder stock taking an essential practice in the coming weeks.
Notes to editors:
- Chief Vet calls for extra vigilance after further detection of Bluetongue in GB 15 October 2018
- Advice for farmers as closed spreading begins 15 October 2018
- Northern Ireland bathing waters amongst the best in Europe 11 October 2018
- Working together to improve our water quality 10 October 2018