The aim of this study was to analyse the gene and genotypic parameters using microsatellites of Creole bovine (CB) from the high southern tropics of Ecuador and contrasting them with registered Holstein bovine (HB); For this, blood was collected from 7 CC and 3 BC subpopulations. Fifteen markers grouped into 4 mixtures were analysed; 1) CSRM60, INRA083, CSSM66; 2) ETH3, HEL9, TGLA53, BM1818, ILSTS006; 3) BM2113, ETH225, TGLA122, ETH10; and 4) TGLA227, INRA032, SPS115. Genetic variation parameters were determined: number of alleles (Na), number of effective alleles (Ne), frequency of null alleles (f-Null), observed heterozygosity (Ho) and expected (He), Polymorphism Information Content (PIC), inbreeding coefficients (Fis), Hardy-Weinberg equilibrium (HWe). In addition, a dendrogram was constructed based on Nei’s distances and identities, and finally, the AMOVA multilocus analysis. In mo...

This study aimed to describe morphological and histological characteristics of ovaries of two genetic groups of guinea pigs from Latin America. Ovaries from 20 improved and 20 native guinea pigs were collected after slaughtering. One ovary from each animal was weighed, measured, counted for visible follicles on the ovarian surface, and used for subsequent oocyte collection by the slicing method. Contralateral ovaries were used to prepare histological sections and quantify follicles. Body and ovary weight and ovary length were significantly greater in improved than in native guinea pigs (p<0.01). Ovarian weight was greater in diestrus than in proestrus (p=0.0632) only in improved animals. The number of primordial, primary, secondary, and total follicles did not differ between genetic groups. The number of antral follicles was significantly greater in improved than in native guinea pigs...