Synchronization and resynchronization of oestrus and fixed-time artificial insemination in buffaloes in Argentina

KONRAD, J.L.; GARRIDO, M.J.; YUPONI, R.; YUPONI, M.; CRUDELI, G.A.

Cartagena de Indias

Congreso; 11th World Buffalo Congress; 2016

Asociación Colombiana de Criadores de Búfalos

Resynchronization programs are useful when artificial insemination (AI) needs to be carried out in the largest number of animals in a short period of time, and allows the return to oestrus of those buffaloes that were not pregnant at fixedtime artificial insemination (FTAI). This technique is able to increase the number of calves born, increasing the farm productivity. The aim of this work was to assess the implementation of synchronization and resynchronization of oestrus in a herd of buffalo in Argentina. Two hundred buffaloes from different categories (buffalo heifers n=55; lactating buffalo cows n=98; and dry buffalo cows n=47) were synchronized for FTAI by Ovsynch protocol. Resynchronization protocol began at 20 days after FTAI, an ultrasound diagnoses were performed 27 days after FTAI, and then resynchronization protocol continued on the 66 non-pregnant buffaloes (buffalo heifers n=32; lactating buffalo cows n=17; and dry buffalo cows n=17). At 30 days after the last AI a second ultrasound diagnoses were performed to evaluate pregnancy rate of resynchronization protocol. Categorical data were analyzed by GENMOD procedure and continuous data by MIXED procedure of SAS. Pregnancy rate on first AI was 49% (98/200), and 42.2% (28/66) for the second one. An overall pregnancy rate of 63% (126/200) was obtained in an interval of 30 days. Pregnancy rates in buffalo heifers were 58.2% (32/55) and 34.4% (11/32) for first and second AI respectively. Significant differences were found (p0.05). Pregnancy rate obtained in this work shows that the application of resynchronization program in buffalo is useful to increase the herd productivity using a superior buffalo bull.