Managing Dairy Cows in Difficult Conditions

Greenmount like all other farms in Northern Ireland has suffered as a result of the very wet summer weather.  Compared to the 30 year average, July and August rainfall was 175 percent of the average with a total of 287 mm of rain.  This has left a legacy of lower livestock performance, poorer quality silage and damaged ground.  This article intends to highlight some of the actions being taken at Greenmount in the aftermath of summer 2009.

The dairy cows at Greenmount grazed as one group from the beginning of June when the weather and ground conditions were good.  Throughout July and August cows were fed to yield through the milking parlour.  To maximise feed efficiency and maintain milk from grazed grass the minimum feed setting was set at zero and only cows producing more than 17 litres got concentrate at a rate of 0.4 KG per additional litre up until mid August when the parlour setting was reduced to M+ 15 litres.  However, with better grazing conditions in previous seasons it was possible to use a M+ setting of 19 litres in July and 16 litres in August, improving both feed efficiency and milk from forage.   

As a result of the wet ground conditions, the cows have been housed at night since the end of August and are being fed a TMR of late first cut and wholecrop silage.  Around 25 cows have calved since the end of August and these are managed as a separate group, being housed both day and night.  Despite the recent improvement in weather conditions and forecast of a more settled period for the next week or so, it is unlikely that the main group of mid and late lactation cows will be out at night again.  This is due to the decrease in grass growth which has affected grass covers across the grazing area, but also due to the limitations of darker mornings and evenings and the need for cows to cross two roads to get to many of the drier paddocks.  GrassCheck results indicate that the grass growth rate at Greenmount this week was 18 KG DM/ha, considerably lower than that recorded in other parts of Northern Ireland and the 42 KG DM/ha recorded at Greenmount in the same week last year.

The availability of winter forage stocks is a changing feast on many farms throughout Northern Ireland and Greenmount is no different.  At the beginning of August a potential feed shortage was recognised so 2 ha of winter wheat originally intended for combining was cut as wholecrop silage.  With the improved weather last week 20 ha of third cut silage was cut, and 12 ha of maize will be harvested next month.  Most of the maize plants have two to three cobs.  The crop looks good and weather dependent should be better than that achieved last year.

At Greenmount there is around 65 t silage DM of early first cut silage with an ME of 11.7 MJ/KG DM and a further 170 t silage DM of later first cut with an ME of 10.9 MJ/KG DM.  If the best quality early first cut silage was fed to the early and mid lactation groups alongside maize, it is anticipated this would run out in December.  Instead, the early and mid lactation cows will be fed a TMR of 40 percent maize, 30 percent early first cut (11.7 MJ ME/KG) and 30 percent late first cut silage (10.9 MJ ME/KG) on a dry matter basis which should make the better quality first cut silage last until March with the expectation of turning some cows out then if weather conditions permit.

At Greenmount, cows in the Future Herd are three feeding groups based on stage of lactation.  The early lactation group is made up of fresh calvers up to 60 days in milk, the mid lactation group made up of cows 60 to 200 days in milk and the late lactation group made up of cows that are more than 200 days in milk.  Grouping of cows allows different TMR mixes to be fed to each group, improving feed efficiency and maximising milk from forage.  This avoids overfeeding, particularly late lactation cows which do not get any blend in the TMR.

With the prolonged period of spring housing and early housing again this autumn there was a lot of slurry and dirty water in the tanks at Greenmount FDC a few weeks ago at the time of year when they would normally be nearly empty.  Some of this slurry has already been spread with the aim being to apply the rest before the start of the closed period on 15 October.  The thicker slurry is being applied to around 20 ha of third cut silage ground while the thinner slurry is being applied to around 20 ha of ground cut for second cut silage and subsequently grazed.

It is likely that the improved weather and ground conditions of the last week will change the forage situation on farms this winter from a quantity issue to one of quality.  Culling will assist in controlling the availability of forage stocks this winter, helping to ensure that there are adequate supplies of the best quality silage available to maintain production.  Lower yielders, dry cows and youngstock may have to eat very poor quality forage.  Pregnancy diagnosis will be key, allowing identification of cows that are not in calf.  The final PD’ing of Greenmount’s Future Herd will be conducted at the end of September, eight weeks after the sweeper bull was removed.  Other cows that could be earmarked for potential culling are those with poor production and those with recurring health problems such as lameness or mastitis.  This will help to reduce the number of cows being carried through the forthcoming winter and help conserve forage stocks.

Pregnancy diagnosis is a useful tool, not only for identifying non-pregnant cows but together with good service records can be used to estimate the number of cows expected to calve each month throughout the winter.  This allows you to establish drying off dates and will help in targeting feed to those cows most responsive to quality forage this winter.  

While barley was harvested four weeks ago, the wet weather conditions delayed baling of the straw.  The weather also delayed ploughing and reseeding.  Areas of grass burned off almost a month ago were not ploughed until last week due to the difficult ground conditions.  In total, around 8.5 ha were reseeded week commencing 14 Sep with 50 percent of this area planted into cereal stubbles.

Feed planning and budgeting will be essential this winter if efficient use is to be made of the silage available.  CAFRE Advisers will be hosting a number of workshops to assist farmers develop and implement a winter feed plan to consider issues specific to their area.

Michael Graham (Farm Manager) discussing winter feed stocks with Philip Higginson (Stockman) and David Mackey (Dairying Technologist)