ABSTRACT: The objectives were to analyze the genealogical information of Gyr (GY) and Nelore (NL) cattle from Costa Rica. Analyzed: pedigree integrity (GY, 13272; NL, 18153); number of complete, maximum traced and equivalent complete generations; inbreeding (FI); generation interval (GI) through four selection routes; average additive genetic ratio (AGR); effective number of founders (fe); effective number of ancestors (fa); effective population size (Ne). The analysis was performed with the ENDOG software. The maximum proportion of unknown parents, grandparents, and great-grandparents was 18.6%, 39.9%, and 59.3%, respectively. The average FI for NL was 8.87% and 2.85% in GY. The average consanguineous population (%) and FI was 53.9 and 16.5% in NL, 28.9 and 9.9% in GY. The average and maximum values of AGR for NL were 3.5 and 12.8, 1.4 and 5.6 in GY. The fe and fa for NL were 65.0 and 38.0, in GY 145.7 and 59.0. The Ne indicated increases in FI in the range of 1 to 2% in GY, for NL greater than 2%, with a status of care to monitor the evolution of F and AGR and their possible implications in genetic improvement. The GI ranged from 6.3 to 7.9 years with a general average of 6.9 years. These results show a summary of the genetic and reproductive management those breeders have carried out.

RESUMO: Os objetivos foram analisar as informações genealógicas de bovinos Gir (GY) e Nelore (NL) da Costa Rica. Foram considerados: integridade do pedigree (GY, 13272; NL, 18153); número de gerações completas, máximas traçadas e equivalentes completas; endogamia (FI); intervalo de geração (GI) por meio de quatro rotas de seleção; razão genética aditiva média (AGR); número efetivo de fundadores (fe); número efetivo de ancestrais (fa); tamanho efetivo da população (Ne). A análise foi realizada com o software ENDOG. A proporção máxima de pais, avós e bisavós desconhecidos foi de 18,6%, 39,9% e 59,3%, respectivamente. O FI médio para NL foi de 8,87% e 2,85% no GY. A média da população consanguínea (%) e FI foi de 53,9 e 16,5% em NL, 28,9 e 9,9% em GY. Os valores médios e máximos de AGR para NL foram 3,5 e 12,8, 1,4 e 5,6 no GY. Os fe e fa para NL foram 65,0 e 38,0, no GY 145,7 e 59,0. O Ne indicou aumentos de FI na faixa de 1 a 2% no GY, para NL superiores a 2%, com status de cuidado para acompanhar a evolução de F e AGR e suas possíveis implicações no melhoramento genético. O IG variou de 6,3 a 7,9 anos com média geral de 6,9 anos. Esses resultados mostram um resumo do manejo genético e reprodutivo realizado por esses criadores.

ABSTRACT The objective of this study was to evaluate the population of Brahman cattle from Costa Rica. Pedigree analysis of 98,749 animals was used to estimate the following parameters: pedigree integrity, as a proportion of known ancestors; the number of complete generations, maximum generations traced, and equivalent complete generations; inbreeding coefficient (F); generation interval (GI) across four selection paths; additive genetic relationship (AGR); effective number of founders (fe) and ancestors (fa); and effective population size (Ne). The analysis was carried out using the ENDOG software. The maximum proportions of unknown parents, grandparents, and great-grandparents were 14.1%, 38.9%, and 61.2%, respectively. Average F for the whole population was 0.86, while 27.4% of the population was inbred, with an average F of 3.1%. The inbred population increased through the time, while F decreased. The average AGR was 0.64, with maximum values of 4.1 and positive trends. The fe and fa were 617.8 and 172.0, respectively. The Ne indicated increases of F, with values lower than 1%. The GI fluctuated from 6.4 to 7.4, with an average of 6.85 years. These results summarize previous breeding practices and represent useful information for designing breeding programs by anticipating the relationship between the selection response and increases of inbreeding.

Resumen Introducción. En Costa Rica, la población de ganado con registro genealógico de la Asociación de Criadores de Ganado Cebú (ASOCEBÚ), no contaba con una caracterización reproductiva ni con parámetros como edad al primer parto (EPP) o intervalo entre partos (IEP), lo cual limita el análisis, progreso genético y productivo de las razas. Objetivo. Caracterizar los métodos de reproducción utilizados en las razas puras cebuínas y calcular la EPP e IEP de una población Brahman gris pura en Costa Rica. Materiales y métodos. Se utilizó la base de datos de la ASOCEBÚ Costa Rica, actualizada a marzo 2018. Se analizaron 10 995 registros de las razas Brahman Gris, Nelore, Brahman Rojo, Gyr, Guzerat e Indubrasil. Se calculó la distribución de los animales según los métodos de reproducción utilizados. Del 32,7 % de la población Brahman gris en ASOCEBÚ, proveniente de las regiones Huetar Atlántica, Brunca y Chorotega, se calculó la EPP e IEP. Resultados. La monta natural, fue el método de reproducción más utilizado (57,8 %) seguido por la inseminación artificial (26 %) y transferencia de embriones (16,2 %). El promedio de EPP en la raza Brahman Gris fue de 41,4 meses con un IEP de 548,9 días. Conclusiones. Es necesario seleccionar animales con mayor precocidad sexual y darles las condiciones para disminuir la EPP e IEP. El uso de la inseminación artificial, mejoró el desempeño reproductivo de los animales Brahman puros. Las asociaciones de bovinos de raza pueden promover la mejora de los animales que registran a través de controles y análisis de parámetros zootécnicos.

Abstract Introduction. In Costa Rica, the population of cattle with a genealogical record of the Association of Breeders of Zebu Cattle (ASOCEBU), did not have a reproductive characterization or parameters such as age at first calving (EPP) or calving interval (IEP), which limits the analysis, genetic, and productive progress of the breeds. Objective. Characterize the types of methods used to breed pure zebu breeds and calculate the EPP and IEP of a pure gray Brahman population in Costa Rica. Materials and methods. The ASOCEBÚ database from Costa Rica, updated to March, 2018 was used. 10,995 records of the Gray Brahman, Nelore, Red Brahman, Gyr, Guzerat, and Indubrasil breeds were analyzed. The distribution of the animals was calculated according to the types of reproduction used. Of the 32.7 % of the gray Brahman population in ASOCEBÚ from the Huetar Atlántica, Brunca, and Chorotega regions, the EPP and IEP were calculated. Results. The natural mounting was the type of most used method (57.8 %) for the reproduction of zebu animals followed by artificial insemination (26 %) and embryo transfer (16.2 %). The average EPP in the Gray Brahman breed was 41.4 months with an IEP of 548.9 days. Conclusions. It is necessary to select animals with greater sexual precocity and give them the conditions to reduce PPE and IEP. The use of artificial insemination improved the reproductive performance of pure Brahman animals. Breed associations can promote the improvement of animals they register through records and analysis of zootechnical parameters.

Resumen Introducción. Existe escasa información sobre ganado puro con certificado genealógico en Costa Rica. Es necesario conocer el estado de esta población para dirigir esfuerzos en la mejora productiva del ganado cebú. Objetivo. Actualizar la base de datos de la Asociación de Criadores de Ganado Cebú de Costa Rica (ASOCEBÚ), caracterizar dicha población y analizar el uso de los machos de la raza Brahman gris en el país. Materiales y métodos. Se realizó un inventario en 121 ganaderías para actualizar la base de datos de la Asociación al año 2018. La información se clasificó por raza, sexo, edad, total de animales, criadores, región socio-económica, provincia y cantón. Se determinó la frecuencia de uso de reproductores Brahman gris. Resultados. Se contabilizaron 10 995 animales puros, distribuidos en seis razas (Brahman gris, Brahman rojo, Nelore, Gyr, Guzerat e Indubrasil). La raza Brahman gris predominó con un 74,5 % de la población y 76,8 % del total de criadores. La región Chorotega presentó la mayor población inscrita (49,5 %) y el mayor número de criadores (37,2 %). El 55,8 % de la población total provino de diez criadores, sin embargo, el mayor número de ganaderías correspondió a fincas con pocos animales. En la raza Brahman gris, el 60,8 % de la población provino de toros nacionales y el 39,2 % del extranjero. Conclusión. Los cebuinos puros registrados se distribuyen en todo el país. Se debe poner atención al manejo genético para minimizar la consanguidad. Se recomienda a los encargados de censos y encuestas, incluir la población de razas puras dentro de las evaluaciones.

Abstract Introduction. There is not much information on pure cattle with a genealogical certificate in Costa Rica. It is necessary to know the status of this population to direct efforts towards the productive improvement of the Zebu cattle breeds. Objective. To update the database of the Costa Rican Cebu Cattle Breeders Association (ASOCEBÚ), characterize this population and analyze the use of males of the gray Brahman breed in the country. Materials and methods. An inventory was done in 121 herds to update the Association’s database to 2018. The information was sorted by breed, sex, age, total animals, breeders, socio-economic region, province, and canton. The frequency of use of gray Brahman breeders was determined. Results. A total of 10 995 pure animals were counted, distributed in six breeds (gray Brahman, red Brahman, Nelore, Gyr, Guzerat, and Indubrasil). The gray Brahman breed predominated with 74.5 % of the population and 76.8 % of the total of breeders. The Chorotega region had the highest registered population (49.5 %) and the highest number of breeders (37.2 %). 55.8 % of the total population came from ten breeders, however, the largest number of herds corresponds to farms with few animals. In the gray Brahman breed, 60.8 % of the population comes from domestic bulls, and 39.2 % from other countries. Conclusion. Registered pure zebu cattle are distributed throughout the whole country. Attention should be put to genetic management to minimize inbreeding. Census and survey managers are encouraged to include the purebred populations in their assessments.