Early Lactation Management - Key to Successful Breeding

Getting the cow off to the best possible start in early lactation is obviously one of the main goals for any dairy farmer. Poor management of the cow during this critical phase in the cow’s life cycle can be attributed to a lot of the fertility issues and body condition loss associated with dairy cows particularly at grass.

The following are some basic tips to help reduce body condition loss and improve fertility in early lactation cows.

1. Monitor body condition score

Peak milk yield occurs before the peak in dry matter intake (DMI) in early lactation. Between these peaks, lactation demand for energy exceeds energy intake and the cow mobilizes body reserves to meet this deficit. Cows that lose a great deal of body condition in early lactation may also suffer impaired reproductive performance. Cows that calve down in the correct body condition score (BCS) at a score of 3 – 3.25 and calve down with minimal metabolic issues are statistically proven to have improved fertility and conception rates at breeding. Minimising body condition loss in early lactation and presenting cows for breeding at a minimum BCS of 2.75 will all aid to improve conception rates during the breeding season.

2. Close the energy gap

Feeding the cow to maximise dry matter intake and energy intake in early lactation can help to reduce the severity of weight loss and improve reproductive efficiency. The more milk a cow produces the more energy she must ingest to minimise negative energy balance in early lactation. For grazing cows you can assume that a 600kg cow will need roughly 6.0 UFLs for maintenance and 0.43 UFLs for every kg of milk. For example, if you have a cow producing on average 25kgs of milk in March, the average requirement for energy is 6 + (25 X 0.43) = 16.75 UFL per day. If you assume average pasture grass contains 0.95 UFL per kg of dry matter (DM) and that cows at this time are ingesting 15kg of DM per head per day (depending on farm specific grazing management and grazing conditions) then the cow ingests 14.3 UFL from grass and requires 2.5 UFL from concentrate (approximately 3kg per day). 

3. Be prepared to react to changes in grass supply

Farmers must note that feeding levels at grass assume a base level of grazed grass intake.  Farmers need to be prepared for a period of low grass growth rate or low grass DM %.  In this case, grass DM intake will fall and cows will lose condition if their energy requirements are not supplied. The best way of predicting these periods is by using the grass wedge technology and measuring pasture covers weekly on your farm with checks made for grass DM %.

4. Don’t overfeed protein

Feeding excess protein to dairy cows is expensive and may have a negative effect on fertility. This excess protein usually ends up in the urine. Also feeding too much protein in early lactation tends to increase the cow’s milk production which leads to a higher energy demand in early lactation during a period when the cows dry matter intake is already lower than her energy demands. The strategy employed should be to use low protein compounds with high energy ingredients for grazing cows. Developing this strategy to limit milk production in early lactation, which favours the cow having a good energy status, is especially useful in a scenario where milk prices are not buoyant and where milk quota issues arise.

5. Look after the rumen

The rumen supplies most of the energy and protein for the dairy cow and can be seen as the engine that drives the machine. The rumen is not designed for abrupt changes so when cows are going to grass too soon or immediately after calving, difficulties can arise as grasses are very digestible and often create an acidic rumen. It is recommended that cows are brought in at night for the first 7-10 days after calving and presented with palatable forage to encourage rumination and allow for gradual dietary changes. Also, cows should start off being fed no more that 2kgs of concentrate in the parlour at one milking. The use of ruminal buffers, such as the live yeast Yea-Sacc® from Alltech®, has been proven to reduce the number of hours that rumen pH is below the critical level of 5.8.

6. Major minerals and trace elements

It is very important to ensure supplementation of adequate amounts of major and trace minerals before and after calving. Trace minerals such as Selenium play a key role in maintaining a healthy immune system in the period around calving. This is important as most dairy cows have pathogens in the womb on day one after calving. A strong immune system is needed for a healthy womb which is critical for optimal fertility. Other trace minerals such as Copper and major minerals such as Phosphorus, play key roles in ovulation or cycling, if there is a deficiency of either then anoestrus is a real possibility. Research has proven that feeding these trace minerals in their organic form such as Bioplex® Copper and Zinc and Sel-Plex®, an organic form of Selenium, leads to these minerals being better absorbed, stored and utilised by the animal.

7. Pre-breeding fertility examinations

It is advisable that all cows receive pre-breeding veterinary examinations one month post-calving to check for residual uterine infections (endometritis) and ovarian pathology. It has clearly been shown that fertility performance improves in herds where cases of endometritis are detected and successfully treated by six weeks post-calving. Similarly, the treatment of ovarian cysts and the management of the anoestrus non-cycling cow are crucial to optimal reproductive performance. Cows that are particularly at risk of uterine infections include cows that had retained placenta and metritis after calving. Uterine infections and ovarian problems are much more prevalent in herds where the transition period was less than optimal and where significant negative energy balance occurs in the post-calving period.

Management of the dairy cow in early lactation is a challenging aspect of dairy farming but managing these seven key areas carefully will lead to a reduction in body condition loss and improved fertility in dairy cows.