Rafael Pineda ¹, Donicer Montes ¹, Darwin Hernandez ¹

Affiliations
1 Facultad de Ciencias Agropecuarias, Universidad de Sucre, Sincelejo, CO

Abstract

Objective: To determine the effect of the FecX^R, FecG^H and FecG^I genetic polymorphisms and other non-genetic effects on the natural prolificacy of Colombian creole hair sheep. Materials: The birth number of the mother, the date of service (season and year), the male used and the prolificacy of 50 OPC females were recorded. The FecX^R, FecG^H and FecG^I loci were genotyped with direct PCR and PCR-RFLP. The allelic and genotypic frequencies, the observed (Ho) and expected heterozygosity (He), the fixation index and the deviations from the Hardy-Weinberg equilibrium (EHW) were calculated. The polymorphisms and non-genetic factors were associated with prolificacy using the GLM procedure. Findings: The FecXR and FecGH loci were monomorphic without the mutated allele, which is why the association analysis with prolificacy was not carried out. The FecGI locus of the GDF9 gene was polymorphic with frequencies of G = 0.89 and A = 0.11. The homozygous AA genotype was not found, and the GG and GA genotypes had frequencies of 0.78 and 0.22, respectively. The Ho was greater than the He; this excess of heterozygotes was not significant and neither were the deviations of the EHW (p>0.05). The average prolificacy was 1.30 ± 0.30. The genotype in the FecGI locus did not significantly affect the prolificacy (p = 0.087) but did so more so in the heterozygotes. The non-genetic effects analyzed, such as the number of the mother’s birth, the season and year of conception, and the father, did not affect the natural prolificacy of the OPC (p> 0.05). Application: The FecG^I and FecG^H loci were monomorphic, and FecGI locus was polymorphic; however, the genetic variation and non-genetic factors were not associated with the prolificacy

Keywords

Bone Morphogenetic Protein-15 Gene, Growth Differentiation Factor-9 Gene, Reproduction

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Darwin Hernandez ¹, Donicer Montes ¹, Luz Angela Alvarez ²

Affiliations
1 Universidad de Sucre-Campus Ciencias Agropecuarias, Sincelejo, CO
2 Universidad Nacional de Colombia-Sede Palmira, Palmira, CO

Abstract

Objectives: To associate the BoLA-DRB3 alleles with the resistance and/or susceptibility to the development of the Enzootic Bovine Leukosis (EBL), in the Harton del Valle cattle. Methods: In 93 animals of the Harton del Valle breed, the infection with the Bovine Leukosis Virus (BLV), the development of Persistent Lymphocytosis (PL), the production of antibodies against the virus (anti-BLV) for one year were evaluated. The animals were genotyped for the BoLA-DRB3 locus. The number of alleles and their frequencies was estimated. Alleles were associated with infection with BLV (env+/-), development of PL (PL+/-) and production of anti-VL (anti-BLVhigh/low) using Odds Ratio (OR), the alleles were classified as Resistant (R), Neutral (N) or Susceptible (S) to the variables evaluated. Additionally, the sequences were explored in order to find common amino acid motifs. Findings: We found 27 alleles BoLA-DRB3, the most frequent alleles were *1101 (14.5%), *0902 (7%) and *2703 (7%), *20012 (6.5%), *1501 (5.9%) and *1701 (5.9%) The remaining 21 alleles had a cumulative frequency of 53.2%. The alleles *1001, *1101, *2006, *2703, *3001 and *4802 were considered as Renv infection with the virus, whereas, the alleles *0902, *1601, *1701, *20012 and *25011 were they considered Senv. Only the allele *1101 was significantly associated with the absence of PL and the alleles *25011 and *2703 were considered SPL. The alleles *1101 and *2703 were Ranti-BLV, while, the alleles *1601 and *1701 were classified as Santi-BLV. The allelic frequencies of the R alleles were higher than the S. Some common amino acid motifs were found between alleles with the same classification. Only the allele *1101 was Renv/PL/anti-BLV. The protective effect of the allele was greater in the heterozygous state (OR = 0.18, p<0.00005). Application/Improvements: The BoLA-DRB3 locus is highly polymorphic. The allele *1101 was considered as Renv/PL/anti-BLV. The heterozygote advantage was shown when responding against the development of the disease. The data presented here can be used in future genetic improvement programs aimed at increasing the frequency of alleles of resistance to the disease.

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Rafael Otero ¹, Darwin Hernandez ¹, Donicer Montes ¹

Affiliations
1 University of Sucre, Sincelejo, CO

Abstract

Objective: To produce bovine transgenic embryos by microinjection of a lentiviral vector that carries the eGFP gene as a marker in zygotes six hours after fertilization. Methods: 834 oocytes were matured and subjected to one of four treatments designed as follows: CC: Control: IVF with Cumulus-oocyte with (COCs), cultivated in CR2 medium supplemented with 10% FBS and incubated at 38.5°C in atmosphere of 95% humidity and 5% CO₂.CCM: Control culture medium: fertilized in vitro for six hours, cultured in medium SOF aluminum in pouches under the same conditions of CC. MC: Microinjection control: Fertilized under the same treatment conditions CCM. After six hours they were microinjected with TALP medium and cultured in sachets with the same conditions of CCM treatment. ML: Microinjected with the lentivirus: Fertilized in the same conditions of the CCM treatment. After six hours they were microinjected with the lentiviral vector carrying the eGFP transgene and cultured in sachets with the same treatment conditions CCM and MC. Findings: The cleavage rate found in CC was higher (p < 0.05) than that observed in the other treatments. The rates of blastocysts found between CC, CCM and MC did not differ significantly (p > 0.05) in them, but yes, with ML (p < 0.05). On average, 76.4% of the zygotes obtained in ML expressed the green fluorescent protein. Application/Improvements: The cult ure conditions used were suitable for CC, CCM and MC, microinjection with lentiviral vector has some influence on embryo development, it succeeded in obtaining transgenic zygotes.

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Darwin Hernandez ¹, Donicer Montes ¹, Jaime De La Ossa-V ¹

Affiliations
1 University of Sucre, Sincelejo, CO

Abstract

Objective: To associate the proviral load (PVL) of the bovine leukosis virus found in the Harton del Valle (HV) breed with the alleles of the BoLA-DRB3 gene. Methods: In 100 HV animals, the PVL was evaluated using a real-time quantitative PCR and a TaqMan probe; the animals were classified according to their PVL in high proviral load (HPVL) or low proviral load (HPVL). Additionally, the animals were genotyped using the PCR-SBT method. The allele frequencies were estimated. Alleles were associated with HPVL (susceptible, S), LPVL (resistant, R) or neutral (N) using the Odds ratio (OR) statistic and the presence of common amino acids in the R and S alleles were determined. Findings: A total of 22 alleles were found, the *1101 was the most frequent. High-frequency alleles accumulate 71.9%. The PVL mean was 129740 copies/μg of DNA. Seven alleles were associated with PVL, alleles *1002, *1601 and *1701 with HPVL (S) and alleles *0902, *1101, *20012 and *2703 with LPVL (R). The PVL of the alleles S and R was 516966 and 75074 copies/μg of DNA respectively. The allelic frequency R and genotype RR accumulated was higher than that of the alleles and genotypes S. The amino acid Glu located in positions 70 of the DRβ peptide chain was common in the R alleles. Application/Improvements: The resistance to the PVL (LPVL) has particularities in each breed since the alleles according to the literature reports are not the same. These results can be used in selection programs in favor of the genes categorized here as R, and thus, decrease the infection rate of the virus.

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