Preparing Transition Cows for Autumn Calving

The transition period has a major influence on cow health, feed intake, and post-calving performance. For cows due to calve in September and October, the challenge can be greater because the effects of prolonged summer heat may still be affecting appetite, rumen fill and feed quality.

The aim of a successful transition programme is to help cows maintain intake before calving and resume strong eating afterwards. This can help reduce the risk of metabolic disorders while supporting early lactation performance.

Hot conditions can reduce rumen fill in both dry and fresh cows, leaving autumn-calving animals less prepared for the demands of early lactation.

Data collected through Premier Nutrition’s TMS system during 2020 showed that rumen fill was lower during the summer than during the winter on the same farms. Dry cow rumen fill fell from 3.52 in January and 3.71 in February to 3.36 in July and 2.94 in August. Fresh cow rumen fill also declined as the average temperature humidity index increased.

This matters because rumen fill before calving is strongly associated with subsequent feed intake and performance. Cows entering lactation with poor rumen fill may struggle to consume enough dry matter to meet the rapid increase in energy and protein demand after calving.

Image description: A chart comparing average rumen fill scores in dry and fresh cows during January, February, July and August 2020, alongside average temperature humidity index. It shows rumen fill declining as summer heat and humidity increase.

Where facilities allow, using separate far-off and close-up dry cow groups makes it easier to manage the changing nutritional requirements as calving approaches.

The close-up period should ideally be set at around 28 days. Data collected on farm has shown that where the close-up group is set at 21 days, cows may actually spend only 14 to 15 days in the pen. This reduces the value of the nutritional programme applied during that period.

Within the close-up ration, the priorities should be to avoid excessive energy intake, maintain dry matter intake and rumen fill, supply adequate metabolisable protein, reduce the risk of milk fever and prepare the cow for the demands of early lactation.

Milk fever prevention may involve the use of DCAD technology or a phosphorus binder, depending on the ration and wider farm system.

Controlling energy intake is equally important. Excessive energy supply before calving can increase body condition and internal fat stores, placing additional pressure on liver function and increasing the risk of fatty liver after calving.

High-quality chopped straw can be a valuable part of the ration because it helps maintain dry matter intake and rumen fill without oversupplying energy. The target should be to keep rumen fill values at 4 or above wherever possible. Straw should be clean, palatable and consistently chopped to help reduce sorting.

Metabolisable protein supply also needs close attention. For a typical dairy cow, the target should be a minimum of around 1,200g per day, with 1,200g to 1,400g being more appropriate in many situations.

This level of supply can help cows maintain or build protein reserves ahead of lactation, supporting milk yield, milk solids and cow health after calving while helping reduce the period of negative protein balance. EnviroPro can be used where additional metabolisable protein is required within the transition ration.

Warm weather can increase the risk of TMR heating, particularly in smaller dry cow groups where feed is mixed less frequently or fed over multiple days.

As yeasts, moulds, and other spoilage organisms multiply, the ration can lose valuable nutrients and become less palatable, further pressuring dry matter intake.

Farmers seeing this issue should review feedout management and ration freshness. More detail is available in our blog, Is TMR Heating Costing You More Than You Think?, which explains the causes of heating and how Cool-It can help preserve feed quality and trough life.

Supporting liver function is another important part of transition management. Cholymet supplies choline, lysine, and methionine to help support liver function as cows approach calving and enter early lactation.

Research published in the Journal of Dairy Science found that including an omega-3 source from 28 days before calving to 28 days after calving increased dry matter intake both before and after calving.

Pre-calving intake increased from 11.6kg to 12.8kg per day, while post-calving intake increased from 17.8kg to 20.3kg per day. The higher intake also supported increased early lactation milk production while helping reduce the negative energy balance associated with early lactation.

Image description: A line graph comparing dry matter intake in control cows and cows receiving an omega-3 source from four weeks before calving to four weeks after calving. The omega-3 group shows higher dry matter intake before and after calving.

Omega-3 fatty acids are also relevant during late gestation because egg development occurs during this period and can be negatively affected by heat stress.

The aim is not simply to increase fat percentage, but to provide the right fatty acids for the required response. Different fatty acids perform different functions within the cow, which is why fatty acid profile matters.

Preparing autumn-calving cows means reviewing the whole close-up programme before the first cows calve. Time in the close-up group, energy supply, ration structure, rumen fill, metabolisable protein and liver support should all be considered together.

UFAC solutions, including Omega-3, Cholymet, EnviroPro and Cool-It can support specific areas of the transition programme, helping protect intake, liver function and nutrient supply around calving.