The transition period for a dairy cow is generally from 3 weeks before calving to 3 weeks post-partum. This period is extremely challenging for dairy cows, so managing this time correctly is vital to achieving optimum cow health and is heavily linked to the overall success of the farm. The successful management of the transition period can determine, future lactations, milk production and quality, calving ease, and longevity in the herd.
The energy demand on dairy cows in the days before calving is immense. The transition cow needs to have the access to the correct nutrition to meet their energy requirements, enabling them to calve down with ease and produce high-quality milk, whilst maintaining their own homeostasis and resistance to any infections.
The poor transition of cow management can often leave cows in an energy deficit and exposed to metabolic diseases and other complications. To combat this, a number of proactive steps can be taken around the time of drying off, pre-calving and post-calving, such as body condition scoring, limiting stress factors and ensuring the best nutrition is available.
Body Condition Scoring (BCS)
At drying off , the ideal is a BCS 3, on a 1 to 5 scale. This should remain the same throughout the transition period. Look at your cows eight weeks before drying off , assess their condition and adjust feeding to arrive at the right BCS on drying off . Cows that lose 1 BCS in transition had greater incidence of milk fever, ketosis, D.A, retained placenta than cows that maintained their BCS in dairy transition (Kim and Suh 2003). Over conditioned cows carry a higher risk of ketosis and fatty liver.
Dry Period
It is necessary to have a minimum of 21 days and some prefer a 42 day period. Either is fine, provided you do not allow the cows to gain or lose weight during this period and that you have dried them off at condition score 3/3.5.
Diet
The diet should be designed to maximise intake and should be a controlled energy diet rather than a high-energy diet. Feeding a low-energy diet prepartum results in increased DMI post-partum, increased milk yield and alleviation of Negative Energy Balance (NEB)” (Huany et al 2014). Dry Matter Intake (DMI) is crucial during the dry period, allowing both time and space for feeding is essential, low DMI will lead to fat mobilization, ketosis, impaired liver function and poor immune function. Dr. Gordie Jones’ “Goldilocks” diet is generally accepted as the standard high-fibre diet, an example is:
- 5kg Dry Matter (DM) whole crop cereal
- 3.5kg DM chopped straw
- 3.5kg DM grass silage
- 75g calcined magnesite
- 1.25kg specialized dry cow mineral
The diet should be supplying a crude protein content of 13- 14%, with a starch level of 12% and an energy density of 10mj/kg/dm. Within the Dry Cow mineral, due to the suppression of the cow’s immune system at this time, it is recommended that a high level of vitamin E be fed, 2000iu’s, along with selenium; shortages of these two minerals have shown to cause retained placentas, fresh cow mastitis or elevated somatic cell count (SCC). Additionally, it is now well proven that both Protected Choline and Protected Methionine are essential for transitioning cows well.
- Rumen Protected Choline decreases fatty liver, increases milk production, decreases Reactive Oxidation Species (ROS) and serves as a methyl donor for methionine regeneration
- Rumen Protected Methionine is required for protein synthesis, and DNA, and is the start (Codon) of every protein generated in the body. Importantly Protected Methionine plays numerous roles in cell structure, protein synthesis, milk production and embryo viability. White (2016)
Nutritionists should target an MP flow of 1,300g per day in close-up cow diets. Van Saun and Sniff en (2014) Adequate MP benefits are:
- Improved disease prevention
- Improved reproduction performance
- Improved milk component yield
- Improved colostrum quality
It is also important that the feed fence is never empty as this will compromise the cow’s immune system and lead to metabolic disorders post-calving. Always aim for 5% refusals for the transition cow fence, and ensure they are pushed up throughout the day. Also, be mindful of feeding rates, they differ for heifers and cows. Pre-partum feeding rate for a heifer is 66g/DM/min and, for a cow 95g/DM/min, and very little difference post-calving; 78.8g/DM/min for a heifer and 106.7g/ DM/min for a cow. So, feed space is vitally important for the heifers to ensure they have time to eat to maximise both yield and growth.
Stressors
- Minimise cow movements, especially five to seven days prior to calving
- Regrouping a cow can be compared to the most stressful event in our lives
- Overcrowding in a close-up pen decreases yield
- Primiparus cows: 2.95kg/d increase in yield (1st 83DIM) when stocked @ 80% v.120%
- For each 10% increase in close-up stocking density above 80% there was a 73 kg/d decrease in milk yield
Attention to detail and you can put “Your” name on the plate above the transition pen!
