Clinical cytogenetics in river buffalo (Bubalus bubalis, 2n = 50): new cases.

Although several studies have been undertaken on river buffalo chromosomes,the clinical cytogenetics is relatively recent in this important bovid. Indeed,only when speci¢c research programs on females river buffaloes with reproductive disturbances and a collaborative work between cytogeneticists and veterinary practioners were undertaken,significant results will be obtained. In this study we summarize the results of a cytogenetic investigation performed during the last three years on females with reproductive problems and two males free-martin. Peripheral blood cultures were untreated and treated with BrdU and H-33258 six hours before harvesting to get normal and R-banded preparations,respectively. Slides were treated for CBA and R-banding techniques. Some specific cases were also treated for FISH-technique. Upon 59 investigated animals,of which 57 were females with reproductive problems and 2 were males free-martin, 14 (24%) were carriers of sex chromosome abnormalities. The following abnormalities were found in the females: (a) sex reversal syndrome (2n =50,XY) in two animals; (b) X-monosomy (2n =49,X0) in one animal; (c) X-trisomy (2n =51,XXX) in one animal; (d) free-martinism (2n =50,XY/XX with different frequencies of female and male cells among the animals) in 6 females; (e) a pronounced C-band polymorphism in the X-chromosomes of two females. Both rectal palpation in all females and direct observation of some reproductive organs (after the animal’s mating) revealed evident abnormalities in the internal reproductive organs.