Are You Keeping A Close Eye To Your Transition Cows?

 

In dairy cattle the transition period is characterized by a number of metabolic changes and management practices that can have an impact in the health and productivity of the cows. Therefore, strategies and monitoring programs that can minimize the negative effects of these events in the herd should be implemented.

 

Generally, the transition period starts three weeks prior to the due date and extends three weeks after calving. Animals are moved to a new pen in preparation for the new lactation where they have to adjust to a new ration, social group, and facilities. After calving, some animals will present some form of metabolic disorder or infection. Transition cows will experience insulin resistance, low feed intake, negative energy balance, lipolysis, weight loss, and reduced immune function during early lactation.

 

Bacterial contamination in the uterus, in addition to a number of hormonal changes, can result in retained placenta and metritis. All these events will have effects on the future performance of the cows and their productivity.

 

 

Sometimes health issues will go unnoticed as animals will not show clinical symptoms. However, subclinical cases will affect productivity and in the long run, they might even have a significant impact in other factors such as reproduction performance and culling rate. For instance, studies indicate that cows diagnosed with subclinical ketosis in the first two weeks of lactation were 20% less likely to get pregnant in the first insemination (Walsh et al., 2007).

 

Considering all the factors that affect the development of the cows, producers should have a good health monitoring program that aims to prevent health problems at the herd level and identify cows at high risk for diseases at the individual level.

 

Numerous screening programs have been proposed with different benefits and advantages. However, producers should adjust to resources available in their farms and create an effective program tailored to their conditions and circumstances. Lack of technology or time should not be an excuse to have a poor health monitoring program.

 

 

Accurate records of all the health events are a good starting point. They will offer a retrospective picture and determine if disease incidence rates are exceeding normal standards.

 

Incidence of clinical diseases such as retained placenta, milk fever, dystocia, metritis, ketosis, and displaced abomasum should be available and be reliable. It is important to be clear and consistent with the records. This will help to give a better diagnostic tool, plan an effective treatment, and evaluate the success of the current management. Furthermore, records should be able to provide incidence of a condition and not be confused by treatment rate. For instance, if there is a case of retained placenta that was not treated, this one should be recorded. On the other hand, if there is a case of metritis and it is treated for 5 days, it should be recorded as only 1 occurrence and not as 5 treatment events.

 

Although clinical cases are important and need to be addressed, they are only showing a fragment of the real situation on a farm. Subclinical ketosis, for instance, can affect up to 40% of the cows in early lactation (Duffield et al., 1998), and yet be unnoticed in many cases. That’s why other monitoring practices are needed in addition to good records.

 

 

Adequate consumption of feed during the prepartum and postpartum periods can have a significant effect in the cows. Measuring the intake is an effective tool to prevent health issues. Animals should be encouraged to eat as much as possible during the post-partum period to avoid negative energy balance, but intake should be controlled during the far-off period to avoid over conditioned cows. Research has shown that cows that were overfed during the far-off period had higher concentrations in blood of BHB (ß-hydroxybutyrate) and NEFA (non-esterified fatty acids) that are correlated with higher incidence of ketosis (Dann et al., 2006).

 

Although feed intake data is a great evaluation tool, in many cases it might be difficult to collect due to the nature of the facilities (free stalls vs tie stalls). However, an estimate will offer a good assessment. Competition for feed can be tough, especially in overcrowded free stall pens; therefore, having enough feed for all the cows will help to enable sufficient intake. If refusals are less than 2% that might be an indication that not all the cows in the group had access to enough feed.