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El objetivo de este estudio fue identificar criterios de selección para mejorar la aptitud reproductiva de la hembra bovina. Para ello se realizaron estudios de pubertad en vaquillonas, y productividad media anual en vacas. El espesor de grasa dorsal medido por ultrasonografía a los 450 días de edad (15 meses) resultó un buen predictor de la edad a la pubertad y un criterio de selección potencialmente utilizable para mejorar la fertilidad de la hembra. La [ver mas...]
 
In order to identify selection criteria to improve the reproductive capacity of the female bovine, we studied 132 heifers born in 2011 and 2012, belonging to 5 genetic groups (GG): Angus (A), Hereford (H), AH, HA and Creole (C) in two years (Trials 1 and 2). After weaning, the presence of corpus luteum, live weight, body condition, rump height, rump fat thickness, rib fat thickness and rib eye area were recorded every 28 days. By DNA analysis we [ver mas...]
 
dc.contributor.advisorMelucci, Lilia Magdalena
dc.contributor.authorPardo, Alan Maxs
dc.date.accessioned2019-05-23T17:50:13Z
dc.date.available2019-05-23T17:50:13Z
dc.date.issued2017-06
dc.identifier.urihttp://hdl.handle.net/20.500.12123/5195
dc.identifier.urihttp://intrabalc.inta.gob.ar/dbtw-wpd/images/Pardo-A-M.pdf
dc.descriptionTesis de maestría para obtener el grado de Magister Scientiae en Sanidad Animal presentada en la Facultad de Ciencias Agrarias, Universidad Nacional de Mar del Plata en Junio de 2017es_AR
dc.description.abstractEl objetivo de este estudio fue identificar criterios de selección para mejorar la aptitud reproductiva de la hembra bovina. Para ello se realizaron estudios de pubertad en vaquillonas, y productividad media anual en vacas. El espesor de grasa dorsal medido por ultrasonografía a los 450 días de edad (15 meses) resultó un buen predictor de la edad a la pubertad y un criterio de selección potencialmente utilizable para mejorar la fertilidad de la hembra. La selección por precocidad sexual brindaría la posibilidad de mejorar la productividad media anual de las vacas y de esta manera la fertilidad del rodeo.es_AR
dc.description.abstractIn order to identify selection criteria to improve the reproductive capacity of the female bovine, we studied 132 heifers born in 2011 and 2012, belonging to 5 genetic groups (GG): Angus (A), Hereford (H), AH, HA and Creole (C) in two years (Trials 1 and 2). After weaning, the presence of corpus luteum, live weight, body condition, rump height, rump fat thickness, rib fat thickness and rib eye area were recorded every 28 days. By DNA analysis we determined the genotype for a total of 70 SNPs of genes involved in the hypothalamic-gonadal metabolic pathways, growth and fat metabolism. On the other hand, in order to evaluate the relationships between the beginning of the reproductive life of the females and their productive efficiency, the annual records of 895 cows (217 A, 253 H, 125 C, 116 AH y 184 HA) born between 1986 and 2009 in Experimental Unit Nº 7 - EEA INTA Balcarce were analyzed to estimate the average annual productivity of the cow (PRODAM), its components of (Co) variance and breeding values (EBV). The environmental differences between the two trials evaluated conditioned the age at which the heifers reached puberty, which was higher in those who had lower postweaning gains. HA heifers reached puberty 54±15 days before C (p <0.05), while the rest of GG did not show differences between themselves (p> 0.05). The rib fat thickness measured by ultrasonography at 450 days of age (15 months) was a good predictor of age at puberty and consequently a selection criterion potentially useful to improve the fertility of the female. Estimation of (co)variance components for PRODAM showed a heritability of 0.14±0.05. Age at puberty of the evaluated heifers was associated with the average annual productivity of their mothers, which would be a good predictor of the productive performance of cows. SNPs in SPAG11 and PTGER2 showed a certain association with age, weight and height at puberty. From the analysis performed, the nutritional conditions immediately after weaning are of vital importance for an earlier presence of the first corpus luteum, an indicator of puberty. The rib fat thickness in the heifers could be used as a selection criterion for sexual precocity. However, it is important for future studies to analyze in more detail the relationship between fat deposition dynamics and the onset of puberty, in order to determine the existence of critical thresholds (minimum and maximum) for the onset of reproductive activity. Selection for sexual precocity provides an opportunity to improve the annual average productivity of cows and thus cattle fertility. At the molecular level, the associations found among the genotypes of the SNPs evaluated should be validated in populations with a larger number of animals before being identified as selection criteria to increase the female fertilityeng
dc.formatapplication/pdfeng
dc.language.isospa
dc.publisherUniversidad Nacional de Mar del Plata , Facultad de Ciencias Agrariases_AR
dc.rightsinfo:eu-repo/semantics/openAccesseng
dc.subjectBovinaes_AR
dc.subjectCattleeng
dc.subjectGanado de Carnees_AR
dc.subjectBeef Cattleeng
dc.subjectSelecciónes_AR
dc.subjectSelectiones_AR
dc.subjectFertilidades_AR
dc.subjectFertilityeng
dc.subjectBovinaeeng
dc.subjectVaca
dc.subjectCowseng
dc.subjectComportamiento Reproductivo
dc.subjectReproductive Behavioureng
dc.subject.otherEficiencia Productiva
dc.subject.otherProductive Efficiencyeng
dc.subject.otherSingle Nucleotide Polymorphysmeng
dc.subject.otherSNPeng
dc.titleCriterios de selección por fertilidad de la hembra en bovinos para carnees_AR
dc.typeinfo:ar-repo/semantics/tesis de maestríaes_AR
dc.typeinfo:eu-repo/semantics/masterThesiseng
dc.typeinfo:eu-repo/semantics/acceptedVersioneng
dc.description.origenEEA Balcarcees_AR
dc.description.filFil: Pardo, Alan Maxs. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación experimental Agropecuaria Balcarce; Argentinaes_AR
dc.subtypetesis


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