Selection and Congenital Disease in Mediterranean Italian River Buffalo

The Mediterranean Italian River Buffalo (MIRB) was developed through a long period of pure breeding and has become one of the most productive buffalo milk breeds in the world. This has been achieved through a national programme of genetic selection, and improved management, feeding, and health monitoring overseen by the national buffalo association, ANASB. The selection goal for Italian buffalo is increased mozzarella cheese production, which goes together with the increase in the quality and quantity of milk production.

Genetic selection and pure breeding are often associated with increased inbreeding, leading increased homozygosity at recessive deleterious loci and the occurence of genetic diseases including stillbirths and developmental malformations. This phenomenon has been observed in MIRB in which the most frequent genetic malformation presently is Transverse Hemimelia (TH), a congenital developmental abnormality characterized by the absence of a variable portion of distal limbs. One or both hind limbs may be affected and very occasionally one forelimb.  TH has been reported mainly in buffalo farms located in Campania where in 2008 there was an incidence between 2 and 5%.  This results in significant economic losses of the farmers. The genetic mutations causing TH have not been discovered and to contain the spreading of TH, sires and dams of affected calves are eliminated, however, given the number of cases, the allele frequency in the Campania population maybe between 15-20% and there are still many cases of TH. Hence the need to identify the genetic mutations and develop a test to identify carriers.