Bovine Lymphocyte Intestinal Retention Defect (BLIRD) is a congenital immune disorder that causes stunted growth. It is found in Holstein cattle, particularly in the descendants of prolific bulls Elton and O-Man, to whom the disease has been traced. The disease is caused by a recessive mutation to the gene ITGB7.
BLIRD was first described in scientific literature in 2023, and the extent of its effects is still being researched.
Affected cattle are unable to retain normal amounts of T-cells in the intestines. This results in an average of 27% reduced growth compared to healthy siblings, as well as abnormal white blood cell values. This can cause additional effects such as increased mortality in affected calves.
Test specific information
‘Early onset’ – This phrase indicates, that the symptoms of the disease can be detected at a lower age. ‘Early onset’ is the opposite of ‘late onset’, in which symptoms may be present at later ages. The phrases are used because the mutation causing ´early onset´ symptoms may be different compared to the mutations causing ´late onset´ symptoms.
The Turnaround Time (TAT) depends on various factors, such as the shipment time of your sample to the test location, the test method(s) and whether the tests are performed completely or partially by a Partner Lab or Patent owner.
The TAT of tests performed at our facilities is normally 10 working days after receipt of the sample at the testing laboratory (VHL, VHP or Certagen). For tests performed by a Partner Laboratory (so-called "partner lab test") or patent owner, the TAT is at least 20 working days after receipt of your sample. Because the shipment time to our Partner Labs or patent owner may vary due to factors we cannot influence, the mentioned 20 working days are therefore an estimate.
Sometimes it is necessary to re-run your sample. We call this a retest. In that case, the TAT will of course be extended.
Location of disease or trait
Trait or disease of the gastrointestinal system.
This DNA test is available for the following breeds: Holstein. Additional information is available in the Frequently Asked Questions (FAQ).
For this DNA test we accept the following materials: Blood EDTA, Blood Heparin, Hair, Semen, Tissue. Please contact Dr. Van Haeringen Laboratorium if you wish to submit other material as listed.
An animal can be free and has in that situation two healthy alleles. When used in breeding this animal will not become ill due to the disease. It cannot spread the disease in the population.
An animal can be carrier and has in that situation one healthy and one disease allele. When used in breeding 50 percent of the offspring will receive the disease allele. Carriers will not become ill.
An animal can be affected and has in that situation two disease alleles. When used in breeding all offspring will also receive the disease allele. Affected will become ill.
This genetic factor is inherited in an autosomal, recessive, mode. This means, that the individual can be free of the disease (homozygote normal), affected (homozygous affected) or carrier (heterozygous).
Carriers may spread the mutation in a population without showing symptoms themselves. Because of this, it is extremely important to identify carriers correctly to prevent spreading of a mutation.
Severity of Disease