Parâmetros reprodutivos de ovelhas Santa Inês e suas cruzas com machos das raças Dorper e Somalis brasileira, obtidas por inseminação artificial laparoscópica com sêmen congelado

The present research aims to evaluate fertility at birth (TFP) and prolificacy (TP) rates of 95 Santa Ines ewes, as well as the age at penis-prepuce “desbridamento” and scrotal circumference at 80 (PE 80), 111 (PE 111) and 200 (PE 200) days of age in 26 young males. The ewes had ages varying from 2 to 7 years old and average weight of 45.3 kg and were submitted to laparoscopic artificial insemination (IAL) with unfrozen semen from two males of the following breeds: Santa Ines (SI), Dorper (DP) and Brazilian Somalis (SO). Of the 26 offspring, seven were SI x SI, 12 SI x DP and seven SI x SO. The mean values found for TFP and TP were, respectively, 43.16% and 1.19, not presenting a significant difference (P>0.05) between genetic groups. For the ID, PE 80 and PE 111 there was no difference between the mean values presented by all three groups (P>0.05), being verified a difference (P<0.05) between the averages of PE 200 of the SI x DP and SI x SO groups. Although the effects of heterosis on TP, ID and PE can be considered as irrelevant, the SO males should not be preferred in breedings with SI ewes with the objective of increasing the production of lamb for slaughter.