CVM/BLAD
Within the New Zealand Dairy population, there are three major genetic defects identified that have a financial impact on the industry.
These are found within the Holstein-Friesian breed and include; Blad, Citrillamenia and CVM.
As technology improves, so will the likelihood of further genetic defects being discovered.
The most severe outcome of all these defects is calf mortality resulting from mating a carrier sire with a carrier female. We have used DNA testing to detect the genetic status in young bulls to be progeny tested.
Those found to be carriers of defects have not been included in the programme. By not selecting these young sires, we will eliminate these defects reasonably quickly from the population.
We have been very proactive in ensuring that clients are exposed to minimal risk by developing its GeneScreen programme. GeneScreen is an ideal tool for ensuring that high genetic merit sires that have recessive genes can be used safely within herds, as the programme will avoid the mating of a carrier sire with a carrier female by exploring and detecting pedigrees that have possible mating conflicts.
IBR (Infectious Bovine Rhinotracheitis)
An acute, contagious virus disease of cattle. Often implicated as an infection which initiates the shipping fever complex. This infection usually occurs in the air passages of the head and the windpipe. However, in females this virus also causes inflammation of the vulva and vagina and abortion. Abortion occurs about 20 to 45 days after infection.
Cattle of all ages that have not been vaccinated or have not recovered from the disease are susceptible to IBR.
Inbreeding
The mating between animals that are more closely related than the average relationship in the breed. In common usage, inbreeding refers to matings between close relatives, such as father to daughter, brother to sister, and half-brother to half sister. Planned breeding programs often use this strategy of breeding to concentrate desired genes in the breeding stock, and fix a "type", or "look". It is a process that exposes both the good and bad qualities in the stock.
Inbreeding does not create undesirable recessive genes, but it does tend to bring to light these unfavorable genetics.
It is however, up to your individual level of acceptance.
Within the Jersey breed, some level of Inbreeding cannot be avoided in most cases because of sires such as Admiral, Berretta and Waiuku being so prolific.
