Herd Health Testing
In addition to milk recording, DHI also offers a variety of health testing options for both individual animal analysis or whole herd screening. With convenience in mind, these tests can be conducted right from your regularly collected milk sample. Our advanced lab technology and multiple locations make herd health testing seamless and affordable.
DHI operates milk analysis laboratories in Ontario, Alberta and British Columbia to serve our widespread customer base. The Guelph laboratory, in addition to completing all of Ontario’s milk sampling, is responsible for all specialized herd health testing for Mastitis, Pregnancy, Johne’s & Leukosis and BVD. Currently, both Alberta and British Columbia labs provide payment and quality testing services for the regional milk marketing agencies for producers in British Columbia, Alberta and Saskatchewan.
SCC (Somatic Cell Count) Testing
SCC testing is an important tool for measuring and managing each cow’s milk quality and ensuring overall herd health. SCC reports provide clear and actionable information that can be analyzed at the herd, lactation group, and individual level. Testing is conducted alongside regular component testing making it an easy and affordable option.
Somatic cells are white blood cells and epithelial cells commonly found in low levels in milk. When a pathogen is present in the udder, high numbers of white blood cells are produced to combat the infection. High levels of SCC indicate that the cow may have an intramammary bacterial infection known as mastitis. A high SCC decreases milk production and quality.
Our milk testing equipment assesses individual cows for SCC levels. The SCC Herd Report provides a complete herd summary, profiles group SCC levels throughout the lactation period and is further broken down by lactation group, and projects a detailed list of animals with SCC over 200,000.
This information can be further analyzed over time to determine where potential bottlenecks in herd management could be. Copies of your results can be sent directly to an advisor(s) of your choosing, including veterinarians, nutritionists, etc.
GestaLab (Milk Pregnancy Test)
Use milk samples to confirm pregnancies easily and accurately. Trusted by farmers around the world, the ELISA-based milk pregnancy test is the most hassle free option and can be used as early as 26 days post breeding.
GestaLab measures Pregnancy Associated Glycoproteins (PAGs) which are only produced with the presence of a fetus. PAGs levels increase throughout the pregnancy and rise in concentration in milk as the gestation progresses. By using your regular milk recording samples, no extra cow disruption is required.
Flexible Testing Options
- +First check: Test as early as 26 days post breeding for early results.
- ++ Second check: Test eligible cows at 75+ days post breeding to check for early embryonic loss.
- +++Dry-off check: Avoid costly dry cow costs and confirm pregnancies before moving animals into dry cow area.
*Automatic testing enrollment available for all options. Discount applies for enrolling for dry-off checks.
Results are indicated as either Pregnant, Open or ReCheck Inconclusive. An inconclusive results is either a true pregnancy where PAGs are on the increase, or may be a recent loss of pregnancy where PAGs are on the decline. Inconclusive results are provided at no charge.
MUN (Milk Urea Nitrogen)
MUN analysis is a great tool to help monitor how your feeding program is performing at the cow and herd level.
A dairy cow uses protein, which contains on average 16% crude nitrogen, which is broken down and used by the animal. Excess nitrogen from protein is converted to urea in the liver. Blood carries urea from the liver to several points of elimination. Some urea finds its way back into the rumen. The animal excretes the rest in the urine, manure or milk.
MUN acts as a flag that signals when the feeding program is not in balance, resulting in lower milk production or higher feed costs. While the protein of different feeds varies in the speed at which they break down into nitrogen, the rumen bacteria require energy for digestion of this nitrogen. An imbalance of available protein and available energy in the rumen will result in the MUN being high or low.
The most common cause of high MUN is a protein/ energy imbalance due to:
- To much or too little protein being fed
- The wrong type of protein in the diet
- Too little rumen available energy in the diet
- Unbalanced sequence of feeds or presentation methods
Benefits of MUN Testing
Improve reproduction: MUN can negatively impact reproduction as it is statistically associated with decreased fertility and lower detectable pregnancy at herd checks.
Improve income over feed costs: Higher herd MUN is associated with higher feed costs. Based on herd results, diets can be balanced to achieve greater efficiency of nitrogen use, lower milk urea concentration, and lower feed costs.
KetoLab (Subclinical Ketosis)
KetoLab is a milk test that indicates the status level and risk for subclinical ketosis. Best used as a herd screening tool, KetoLab measures the level of BHB, a ketone body. Ketosis is a common metabolic disease that affects cows typically in early lactation. The KetoLab Report shows the percentage of positive cows, along with a herd trend of the last 10 DHI tests.
Subclinical ketosis is hard to detect as visible signs are not often present. Studies have shown that subclinical ketosis can be quite prevalent and affects as many as 40% of cows in early lactation. It can be very costly due to lower milk production, higher incidence of mastitis and metabolic diseases, and negative impacts on reproductive performance. The only way to monitor subclinical ketosis in the herd is to test for it.
The first few weeks during lactation are the most critical time for ketosis occurrence. Therefore, herd results are reported in 2 categories: 5-21 Days in Milk and 22-42 Days in Milk.
- Percentage of cows with elevated BHB levels, ‘Positive’;
- Herd trend for the last 10 Lactanet tests;
- 3-month period trends;
- Individual cow results between 5-90 DIM
- 5% Positive: Low-Very Good
- 5-10%: Low-Good
- 10-20%: Average (improvements possible)
- 20-40%: High
- Greater than 40%: Very High
Mastitis4 is a milk DNA test that identifies the presence of four mastitis pathogens commonly referred to as the contagious pathogens: Staph. aureus, Strep. agalactiae, Mycoplasma bovis, and Prototheca. The test is based on polymerase chain reaction technology (PCR). Using your regular milk sample, confidently test animals to determine if contagious mastitis is present. PCR technology has a high degree of sensitivity for bacteria DNA and does not rely on traditional bacteria growth (i.e. culture).
- Entire herd
- Selected cows (such as newly purchased, or cows showing repeated signs of clinical mastitis)
- Cows that exceed a certain SCC level threshold (samples can be auto-directed to from the SCC test to the Mastitis4 test)
Targeted: Mastitis4 identifies exactly which contagious pathogens are present. These pathogens can spread easily from cow to cow at milking time, and for Staph. aureus and Mycoplasma bovis , are difficult to treat. Prototheca infections are not treatable.
Reliable: The test is based on polymerase chain reaction (PCR), which detects the presence of the bacteria’s DNA in the milk sample. You no longer have to rely on the ability of the bacteria to grow under culture conditions. Even if bacteria is dead, pathogen DNA can be detected.
Convenient: Your regular DHI sample can be used! No more messing around with time consuming sample collection, storage and shipment.
- Fast: Once samples are in the lab, results are usually available within a day.
Using your milk sample is a quick and easy way to screen your herd for Johne’s Disease. Cows infected with Johne’s Disease will produce antibodies to fight off the infection. The test uses Enzyme-Linked ImmunoSorbent Assay (ELISA) technology to detect the antibody in a milk sample.
Johne's Disease is a bacterial infection that causes abnormal thickening of the lining of the intestinal tract in infected animals, restricting the absorption of nutrients. It is spread through the shedding of the bacteria in manure, which can contaminate feed or water, and also can be transmitted to calves through colostrum from infected cows.
Clinical symptoms include long lasting diarrhea and extreme weight loss despite maintaining some appetite. The impact on profitability of a herd includes reduced milk production, increased involuntary culling, loss of heifer sales and reduced beef production.
Herd owners will receive two sets of reports each time animals are tested for Johne’s Disease: Herd Screening Summary and Cow Screening Report. Contact your veterinarian to assist in the interpretation of your test results. Even if all cows test negative it is still possible for there to be some truly infected cows in the herd. Testing more than once is advisable.
The milk test for Leukosis is very accurate in finding positive cows. Using Enzyme-Linked ImmunoSorbent Assay (ELISA) technology, the milk test detects the antibody that is present when a cow is infected with the Leukosis virus. The antibody develops within three weeks of exposure to the virus.
Leukosis (Bovine Leukosis Virus), is a blood borne viral infection which can cause tumours in the lymph nodes, uterus, heart, abomasums, spleen, kidneys and brain. The disease is spread by transfer of blood cells from infected animals via such sources as re-use of contaminated equipment, colostrum and waste milk and transmission to the calf before it is born.
Clinical symptoms caused by resulting tumors include weight loss, decreased milk production and immobility.
Impact on profitability of a herd includes reduced milk production in infected cows and condemned meat at slaughter, as well as potential costs associated with lost marketing opportunities such as the sale of replacement stock, bulls to AI or embryos, domestically and to international markets.
Bovine Viral Diarrhea (BVD) is a milk sample test which gives you the option of screening your adult milking herd with the sensitive polymerase chain reaction (PCR) test, or test only selected cows with the cost-effective ELISA antigen test.
BVD is a viral infection in cattle, which has a negative impact on herd performance and can result in significant economic losses. Common signs of infection include respiratory problems, infertility and abortion which eventually lead to reduced milk production and early culling.
This test is designed to identify Persistently Infected (PI) animals. PI animals are infected for life and constantly shed the BVD virus. The recommended course of action is to use this test firstly for herd screening. If PI animals are present, BVD can then be tested at the individual cow level to determine the specific source of the virus.
Custom Lab Samples
On a per-test basis, or part of a 4-test package, individual milk samples can be analyzed for fat, protein, SCC, and MUN. Reports are returned to the producer directly from the lab, or distributed to the advisor of your choice.