State of inbreeding and genetic trends for estimated breeding values in IVF embryos and oocyte donors in the Brazilian Guzerá cattle.

Autor: Perez BC; Department of Animal Science, College of Animal Science and Food Engineering, University of São Paulo (FZEA/USP), Pirassununga, 13630-000, São Paulo, Brazil. Electronic address: brunocpvet@usp.br., Balieiro JCC; College of Veterinary Medicine and Animal Science, University of São Paulo (FMVZ/USP), Pirassununga, 13630-000, São Paulo, Brazil., Oliveira Junior GA; CRV Lagoa, Sertãozinho, São Paulo, 14174-000, Brazil., Andrietta LT; Department of Veterinary Medicine, College of Animal Science and Food Engineering, University of São Paulo, Pirassununga, 13630-000, São Paulo, Brazil., Vizoná RG; College of Veterinary Medicine and Animal Science, University of São Paulo (FMVZ/USP), Pirassununga, 13630-000, São Paulo, Brazil., Ventura RV; College of Veterinary Medicine and Animal Science, University of São Paulo (FMVZ/USP), Pirassununga, 13630-000, São Paulo, Brazil; Beef Improvement Opportunities (BIO), Elora, N1K 1E5, Ontario, Canada; Department of Biosciences, University of Guelph, Guelph, N1G 2W1, Ontario, Canada., Bruneli FAT; National Center of Research on Dairy Cattle, Brazilian Agricultural Research Corporation (CNPGL/EMBRAPA), Juiz de Fora, 36038-330, Minas Gerais, Brazil., Peixoto MGCD; National Center of Research on Dairy Cattle, Brazilian Agricultural Research Corporation (CNPGL/EMBRAPA), Juiz de Fora, 36038-330, Minas Gerais, Brazil.
Jazyk: angličtina
Zdroj: Theriogenology [Theriogenology] 2019 Feb; Vol. 125, pp. 71-78. Date of Electronic Publication: 2018 Oct 29.
DOI: 10.1016/j.theriogenology.2018.10.025
Abstrakt: The main objective of this study was to verify genetic trends for milk production (MY305) and age at first calving (AFC). Were also considered levels of inbreeding practiced in the Brazilian dual-purpose Guzerá population (T POP ) comparing it with the same parameters estimated for two sub-populations derived from the reference (T POP ): female donors submitted to ovum-pick up (D POP ) and in vitro embryos produced (E POP ) between 2003 and 2013. Estimated breeding values (EBV) and inbreeding coefficients (F) were regressed by the year of birth (or year of in vitro fertilization) of each animal or embryo in order to obtain annual trends for these parameters separately for each of the three populations studied. A positive quadratic (β 2  = +0.000075) effect was detected for the F values in T POP . Both D POP and E POP showed positive linear coefficients (β 1 ), respectively, +0.00084 (P < 0.001) and +0.00024 (P > 0.05). Annual mean F for E POP was higher than T POP and D POP through the time series studied. The frequency of individuals with more than 7% F was higher in D POP . Genetic trends for AFC were -0.187 days/year (P > 0.05); -0.557 days/year (P < 0.05) and -1.48 days/year (P < 0.05), respectively for T POP ; D POP and E POP . Genetic trends for MY305 were +6.75 kg/year (P < 0.001); +8.2 kg/year (P < 0.001) and +10.5 kg/year (P < 0.05), respectively for T POP ; D POP and E POP . For both traits analyzed, E POP showed the highest regression coefficients, which confirms a higher selection pressure and lower generation intervals previously expected from this sub-population. Results reported in the present study suggest that mean F is increasing in the Guzerá population. Efforts for controlling inbred mating on in vitro fertilization should be considered, as the presence of a bottleneck effect seems to be getting shape on D POP and E POP .
(Copyright © 2018 Elsevier Inc. All rights reserved.)
Databáze: MEDLINE
Externí odkaz: