This is the second article discussing transition cow management. In the first article (January 1, 2010), I discussed the importance of tracking the many complex cow issues associated with parturition. In this article, I will discuss a few approaches to manage cows during the transition period to minimize the long-lasting effects of ‘parturition complex’ on cow performance. With milk prices better than last year and cow inventories generally low, now is an excellent time to maximize production per cow by managing the transition period.

There are three critical time periods to manage transition cows. The first is calving day. On calving day, dry matter intake can decline 40 percent, making it impossible to meet the cow’s nutritional needs. The cow faces short-term calcium deficiency as she begins to produce milk. Tremendous hormonal and metabolic stresses also spike on calving day. Health issues associated with calving must be well-managed for individual cows during this one- to three-day period.

The other two periods last longer than a couple of days. One is the two to three weeks prior to calving. During this period, dry matter intake levels are a critical factor in future performance of the cow. Maintaining intake is the paramount goal for this period.

The last period is the 30 to 60 days after calving. During this period, dry matter intake cannot keep up with the huge energy demands of high milk production and cows mobilize large amounts of bodyweight reserves, fat and muscle, in order to compensate for negative energy balance. Minimizing ketosis is the major goal for this period.

To manage these three crucial periods, I recommend a two-pronged approach. First, I recommend an individual cow management plan at calving. More on this later. Second, I recommend a management plan for groups of cows implemented through the ration for the latter two periods (three weeks before calving through 30 to 60 days in milk).

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Prior to calving, a nutritionally sound ration:

1. limits potassium consumption (the primary factor for hypocalcemia at calving) or balances cations using anionic salts if excess potassium is present;

2. provides proper energy balance (both deficiencies and excesses are a problem);

3. maintains high levels of pounds of intake leading up to calving day (Bulkier rations can often help maintain physical intake because at this stage, energy intake seems to be the major driving force of consumption for cows.);

4. introduces the feeds the rumen microorganisms will encounter in the lactation ration to allow for the approximately two weeks required to shift rumen populations and produce the absorptive papillae on the rumen wall; and

5. yields enough propionate or provides other glucose precursors in order for the cow to maintain proper blood glucose levels at calving.

During early lactation, energy balance is the most limiting ration factor. Higher-energy-density rations are required. Two important concepts for these rations include making sure that the rations do not induce sub-acute ruminal acidosis (SARA) and that they still provide precursors to maintain proper blood glucose levels. Often fat is added to rations to increase energy density. However, we must keep in mind that added ration fat is metabolized through the same pathways as body fat that the cow mobilizes and thus can lead to accumulation of ketone bodies. It is important to shift enough energy supply to glucose precursors to maintain adequate blood glucose levels. This is often done by maximizing propionate yield, which primarily comes from grain under normal ration conditions, without creating SARA.

One of the most useful technologies I know of for these two ration periods is an effective direct-fed microbial (DFM). Effective DFMs often include yeast, lactic acid- producing bacteria, enzyme-producing bacteria or fungi, and select strains of propionibacteria, or combinations thereof. These technologies have been shown to improve intake, improve digestive efficiency, maintain digestive tract microflora balance, reduce the effects of SARA, and in some cases, increase the propionate yield from the ration. All of these effects can provide maximum return at these stages of a cow’s production cycle.

Numerous studies on the effects of yeast have been conducted. Studies have shown the effects of lactic acid- producing bacteria on maintaining microbial balance and one study indicates they possibly help cows cope with acidotic rations. Research showed that propionibacteria (strain P63) actually directly metabolizes rumen lactic acid to propionate and reduces rumen acidosis. Research shows another propionibacteria (strain P169) increases propionate yield, which improves blood glucose supply from a given ration. P169 research also showed increased milk production or improved efficiency improved energy balance as indicated by reduced ketosis levels and better bodyweight maintenance post-calving, improved reproductive performance as indicated by increased pregnancy rates, and improved immune status as indicated by a reduction in retained placenta/metritis complex.

For managing cows individually at calving, I also recommend DFMs along with key nutritional components such as readily available calcium (chloride, propionate forms), glucose precursors (propionate, propylene glycol), supplemental niacin, high levels of antioxidant vitamins (A and E), B complex vitamins and chelated trace minerals, including selenium. These are often administered to cows as boluses, pastes, and low- or high-volume drenches once or twice daily for one to three days. Each administration method has its advantages and disadvantages and should be analyzed for which best fits your operation. This is a targeted program to address the likely nutritional deficiencies present due to low feed intake and to get cows back onto full feed intake as rapidly as possible.

One example of implementing such a program is a field trial from a California dairy with no history of clinical ‘parturition complex’ diseases. This dairy administered an effective capsule program, on calving day only, to every other cow that calved (125 treatment cows, 125 control cows). After four months of lactation, the treatment cows had produced an average of 327 pounds more milk for a net return on investment of almost $40 per cow.

Another example is the results from field trials run on two large New Mexico dairies with hospital pen incidence rates of 11 percent and 15 percent. These dairies implemented a volume drench program featuring readily available calcium, glucose precursors and DFMs administered once on calving day and once the following day. On both dairies, hospital incidence rates dropped to 4 percent, milk production increased five pounds per cow and conception rates increased about 10 percent over the eight-month duration of the trial, which included the hot summer months. The net return from these improvements was calculated at $90 to $196 per cow.

Even if you do not identify ‘parturition complex’ as an issue on your dairy, incorporating the aforementioned supplements into your routine calving protocol can produce excellent economic returns. Coupling them with using DFMs in rations around calving time will produce even better animal production, reproduction and health. These simple programs are great profit centers on most dairies, and yet they are often overlooked. I recommend that you take advantage of them. PD

William Zimmer is a veterinarian and president of Bio-Vet, Inc., in Blue Mounds, Wisconsin.

References omitted due to space but are available upon request by sending an email to editor@progressivedairy.com .

William Zimmer