Effective communication between a dairy herd’s advisers can greatly enhance its performance. The herd veterinarian and nutritionist are usually both key individuals that have a vested interest in a dairy’s success, and making sure they are both working together as effective team members to evaluate current programs and set new goals is a mark of most successful dairies.
The interaction and relationship between the nutritionist and veterinarian can be challenging, as their areas of knowledge and expertise often overlap.
However, the dairyman is well served by a respectful relationship in which each is free to challenge the current practices on a farm, with a common goal of higher performance.
I have seen this relationship thrive when a herd has structured team meetings on a regular basis, but I have also seen it work effectively without these scheduled meetings, as long as the individuals involved have developed effective communication habits.
These are usually fostered by the owner but can be by one of the other individuals (email is a great tool). I have worked both as the herd veterinarian working with a nutritionist and as a nutritionist working with the herd veterinarian.
From either role, the following herd information should be reviewed and evaluated, with the goal of maximizing herd health, performance and profitability.
For most herd numbers, it is important to not only look at herd or group averages but also at distribution. I prefer to look at scatter plots, where each point represents one cow.
Then the average and distribution can be visually evaluated. The following measures are ones I believe should be of interest to both your veterinarian and nutritionist on a regular basis.
Our understanding of what causes low butterfat in cows has improved in recent years, and there are certainly reasons that do not include subacute rumen acidosis (SARA).
Nonetheless, if more than 10 to 12 percent of a Holstein herd is testing below 3 percent butterfat, the possibility of SARA should be investigated. Causes that could trigger SARA include particle sorting, inconsistent mixing of a TMR, overcrowding, inadequate buffer, heat stress or inadequate effective fiber.
Both your herd veterinarian and nutritionist should be concerned if SARA is occurring in the herd due to its long-term negative effects on health and production.
Too high a butterfat in early lactation can also signal health problems. If fat mobilization is excessive, high amounts of free fatty acids will be delivered to the mammary gland, raising butterfat.
There are other, more sensitive and specific tests that can more accurately determine if excessive negative energy balance in early lactation is a concern, but milk fat percentage above 6.0 percent in early lactation Holsteins can be a crude indicator of a problem.
Again, it is important to look at the distribution of a population using these indicators and not just the average.
Herd milk urea nitrogen values
The milk urea nitrogen values for a herd are a useful indicator of the relative balance between the available carbohydrate and available nitrogen for microbial protein production in the rumen. Excessive concentrations of milk urea nitrogen in the blood have been linked to reduced fertility.
Your nutritionist is interested in milk urea nitrogen values for each group of cows to help evaluate the diet’s efficiency; your veterinarian is interested in optimizing fertility.
Death rates in dairy herds have received prominent attention recently. In general, they are increasing. Deaths are costly, and they frequently can be a black eye for our industry. Some are unavoidable, but the national average is high – around 7 percent.
I work with herds that are able to achieve consistent death rates of less than 3 percent per year, and targeting less than 5 percent is a realistic and achievable goal. It is also useful to know when deaths are occurring in lactation.
A lot of dead cows in early lactation likely indicates a problem with transition cow management and nutrition. Your herd veterinarian and nutritionist may not be aware of the death rate in your herd.
Development of a herd plan to investigate deaths that includes the utilization of necropsy exams is often the first step in stopping a death rate that is too high.
Metabolic disease incidence
Two developments in dry cow nutrition have significantly reduced the rate of metabolic disease in dairy cattle. The first is the utilization of dietary cation-anion balance in the formulation of dry cow diets, significantly reducing the rate of milk fever.
The second is the adoption of low-energy diets to dry cows, often utilizing bulky ingredients such as straw or corn stalks, to prevent the overconsumption of energy.
Rates of displaced abomasum (DA) have been significantly reduced on these diets, often to less than 2 to 3 percent of the milking herd.
Incidence rates of metabolic diseases such as milk fever, ketosis, retained placenta or DA can be hard to track on some dairies, but if they can be standardized these rates can provide valuable information.
Of the listed diseases, DA is one that is relatively consistent in its definition and can be most easily monitored. Your veterinarian is likely more aware of your DA rate than your nutritionist – but both should be.
Blood beta-hydroxybutyrate concentrations during the first or second week of lactation may be more useful than clinical ketosis rates, but again, use the distribution and not the average. Some measure of metabolic disease rates should be available and utilized by both your veterinarian and nutritionist.
Early lactation production
Ultimately, the goal of an effective transition program is to permit the early lactation cow to “hit the ground running” – to start milking and eating well.
First test day milk production – or some more refined indicator such as transition cow index, week 4 milk production or first mature equivalent projection – is a useful monitor of transition program success.
This number, stratified by lactation group, is usually more easily obtained than rates of metabolic disease and can be more effectively monitored. Slow starts lower productivity and profitability.
Both you and your advisers have an incentive to see them optimized. They are influenced by the total management of the transition cow – environmental, social and nutritional. Improving them takes a true team effort.
Reproductive performance and days in milk
Days in milk (DIM) of your herd has a huge influence on its potential milk production. Each day beyond 160 DIM has been suggested to lower daily production by approximately 0.2 pounds per cow.
Thus, it affects the ability of your nutritionist to maximize your herd’s production and profitability, and it is determined by the prior success or failure of your reproductive program (unless your herd seasonally calves).
Monitor your overall pregnancy rate as well as the success of your breeding by cycle or stage of lactation. This may provide clues to both your veterinarian in designing breeding and vaccination protocols and your nutritionist in adjusting your cows’ rations.
Effective communication between you, your nutritionist and your veterinarian will improve your overall herd performance. Set up a system where key parameters are routinely monitored and discussed, and work to continuously improve your farm by harnessing the expertise of all of your advisers. PD
Brian Gerloffis District Manager with Renaissance Nutrition. Email Brian Gerloff .