EFECTO DE LA MONTA NATURAL Y EL USO DE DIFERENTES TIPOS DE SEMEN SOBRE LA PRODUCTIVIDAD DE LA CERDA.

The effect of natural mating and the use of different types of semen were assessed on the productivity of 160 sows by forming four lots of 40 with the following arrangement: 1) Natural mating (MN); 2) Insemination on a cervical level with diluted and refrigerated semen from national origin (SDRN); 3) Insemination at uterine level with diluted and refrigerated imported semen (SDRI) and 4) Insemination at a uterine level with imported frozen semen (SCONGI). The synchronization of the sows was carried out by the weaning of the piglets with an average of 21 days of breast-feeding, detecting oestrus twice a day (9:00 to 11:00 and from 16:30 to 18:00) with the aid of a male pig. The fertility average results indicate that the SDRN group reached the best percentage with 85%, compared to the MN, SDRI and SCONGI (77.5%, 57.5% and 65.7% respectively), determining a considerable statistic difference (P>0.05), between the SDRN and SDRI groups. The same was observed in relation to the number of piglets born per litter, which was better with SDRN (11.4) than with MN, SDRI and SCONGI (10.7, 9.3 and 6.9 respectively), showing a considerable statistic difference (P>0.05) between SCONGI in relation to MN, SDRN and SDRI, determining a difference of 4.5 piglets less per litter than when obtained with SCONGI in relation to SDRN. It is concluded that no matter where the frozen semen is deposited for insemination, it will have a lower percentage of fertility in relation to refrigerated semen and natural mating, and the same occurs in relation to the total number of piglets born per litter. [ABSTRACT FROM AUTHOR]