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Incomplete milking challenges early-lactation health woes

Andrea Haines for Progressive Dairyman Published on 08 March 2019
tiestall milking

It’s no surprise that dairy producers are always looking for ways to improve herd health, especially within the fresh cow members of the group. After all, the benefits of investing in healthy practices almost always outweigh the work.

An Agriculture and Agri-Food Canada (AAFC) researcher from the Sherbrooke Research and Development Centre, Dr. Pierre Lacasse, has dedicated much of his time to improving health in early-lactation dairy cows. His discovery of an “incomplete milking” during the first five days of lactation has resulted in much more positive health outcomes for the cow. This method has provided the cow’s metabolism time to adapt, and the result is a sharp drop in metabolic and immune disruptions.



Lacasse began his studies in 2006, initially prompted by the vast transition from “non-milking” to calving and then to a “milking” status. The researcher felt there was room for improvement within this tasking transition.

“Despite the fact nutrient supply through periparturient nutritional management has been the object of considerable efforts, the transition is still the most critical period for all dairy cows,” he says. “Although calving is always a stressful event, in nondairy cows, there are much fewer problems. When the cow is nursing a calf, the milk required to fulfill the needs of the offspring is lower in the first weeks of life, so the transition from pregnancy to lactation is gradual. In contrast, there is no physical limit to the ‘appetite’ of a milking machine such that, in current dairy practices, the demand is already maximal on the first day of lactation.”

Lacasse continues, “As dairy cows have been selected for higher milk yield, expressing for her full potential for milk production just after calving puts her in a very demanding position. So I concluded that it might be wise to try to slow down the influx of milk production for a few days to give her the chance to adapt.”

His studies have shown a multitude of benefits to allowing cattle to adapt for this short time. “The main advantages of this approach is not only the direct reduction of costs. Negative energy balance is an important risk factor for metabolic and infectious diseases, lameness and reproduction problems,” Lacasse says.

“Up to now, we have shown that partially milked cows have lower levels of ketone bodies, which are the cause of hyperketonemia,” he explains. “They maintain higher blood levels of glucose. The blood’s concentration of free fatty acids (also called non-esterified fatty acids [NEFA]) remains lower.” Lacasse says this is important as they have seen that it inhibits the functions of important leukocytes (white blood cells to fight off infections). “We have also found some indications that blood calcemia is improved when milk production is limited (low blood calcium causes milk fever),” he says.


He does admit immunosuppression (changes in immune system response) is too complex to be easily defined. However, in a recent field trial conducted on commercial farms by Dr. Simon Dufour from the Université de Montréal’s veterinary centre, it was observed that cows incompletely milked were more likely to eliminate intramammary infections. Lacasse says this method does not replace the need for a good environment, appropriate feeding and good management. It is a complementary element to add to an already strong system.

“As the field trial has confirmed the findings from the research farms, we believe that the method is proven,” Lacasse says. “However, some work is still needed to optimize the method. For example, in the field trial, we got the best results on reproduction in second-lactation cows. It’s possible that adult (mature) cows would benefit from extending the period of incomplete milking. In addition, we would like to run an experiment in order to respond to some concerns brought on by the milk producers.”

Dairy Farmers of Canada and Novalait (a joint fund from dairy farmers and dairy processors of Quebec) have contributed financially to this research program.

“Reducing the amount of milk harvested for five days is not a big financial loss as most of it is colostrum and cannot be sold,” Lacasse says. “The biggest pushback was the belief that milking incompletely will elevate the risk of mastitis. We have clearly proven it is not the case as we have observed that cows incompletely milked were more likely to eliminate intramammary infections. However, we would like to perform an additional study to respond to concerned producers.”

So how does it work? Lacasse’s research team recommends harvesting 10 kilograms of milk per day for the first three days of lactation and then increase to 12 and 14 kilograms per day for days four and five. “This represents about one-third of what these cows would have yielded if milked completely. These numbers could be adapted according to the level of milk production of the herd,” he says. “It’s a relatively simple method to implement for well-organized producers. If your milking system allows you to see milk production data while milking the cow, there is no further investment needed. If not, ‘tru-test’ scales (milk control) could be used. A producer can try it for a few months and, if he sees no benefits, he can continue back to complete milking.”

For dairy producers with herds other than Holsteins, there are some slight differences in approach. “Breeds that have been highly selected for milk production and experience larger energy deficit will benefit the most from this method,” he says. “As our experiments were performed in Holstein cows, the amount of milk harvested may need to be adapted for smaller breeds. Nevertheless, it is not the breed that is most important, but the extent of negative energy balance.”


Lacasse notes first-calf heifers do not experience large energy deficit and will probably not benefit (still to be tested) much from this method. He says it may be interesting to perform incomplete milking for a longer period in organic herds, where cows can be in energy deficit for several weeks due to the proportion limitation of concentrates in the diet of the cow.

Because diet plays a large role in the practice of healthy calving and lactations, it’s no surprise it would impact an outcome to any method.

“When you have a deficit, you can either elevate the ‘income’ or reduce the ‘expenditure.’ Accordingly, improvement of nutrient supply through periparturient nutritional management has been the object of considerable efforts,” Lacasse says. “Although a good nutritional management plan is essential, it is unlikely that it will, alone, be able to reduce the incidence of periparturient diseases to an acceptable level. In addition, the benefits that they bring must overcome the increase in feed costs associated with them.”

The research team’s efforts to go “against the grain” by proposing to improve energy balance by limiting milk production temporarily in early lactation has been proven fruitful. The team has tested two approaches, milking once a day or incompletely during the first week of lactation. “Both approaches improve energy balance and reduces metabolic and immune disturbances,” Lacasse says. “However, as milking once a day (but not incomplete) has a small negative impact on subsequent milk production, it is likely the best approach.”  end mark

Andrea Haines of ALH wordandimage LLC is a freelance writer from Union Bridge, Maryland.

PHOTO: Staff photo.