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Mendoza Y.,Institute Investigacion Agropecuaria | Antunez K.,Institute Investigaciones Biologicas Clemente Estable | Branchiccela B.,Institute Investigaciones Biologicas Clemente Estable | Anido M.,Institute Investigaciones Biologicas Clemente Estable
Apidologie | Year: 2014

Nosema ceranae is one of the causative agents of Nosemosis, a severe disease that affects the honeybee Apis mellifera. The aim of the present work was to compare N. ceranae and RNA virus infections in Africanized bees (hybrid of Apis mellifera scutellata and A. m. mellifera) and European (Italian) bees (A. m. ligustica) under field conditions. Africanized and Italian healthy colonies were relocated to an Eucalyptus grandis plantation, a place where colonies inevitably acquire Nosemosis. Fifteen and 30 days after that, all colonies presented N. ceranae spores although Africanized bees were less infected than Italian bees. Sacbrood virus (SBV) and Black queen cell virus (BQCV) were detected in both races of bees, although Africanized bees presented a lower level of BQCV infection than Italian bees. At the end of the flowering period, Africanized colonies had a larger honeybee population and produced more honey than Italian colonies. These results suggest that Africanized bees may be able to limit N. ceranae and BQCV infections within the colony, and that this may allow them to be more productive. © 2013 INRA, DIB and Springer-Verlag France. Source


Villalobos-Cortes A.,Institute Investigacion Agropecuaria | Martinez A.,University of Cordoba, Spain | Vega-Pla J.L.,Laboratorio Cria Caballar | Landi V.,University of Cordoba, Spain | And 3 more authors.
Italian Journal of Animal Science | Year: 2015

This study aims to analyze the within-breed genetic diversity and determine the genetic relationships among the most important zebu populations introduced in the American continent from Asia. Gyr (GYR), Red Sindhi (SIN), Nellore (NEL), Guzerat (GUZ) and the synthetic Brahman (BRH) breeds have been established especially in American tropical regions. Estimates of genetic structure and diversity were carried out within and among the five populations studied. The results of withinbreed genetic diversity showed medium to high medium values of diversity in all genetic parameters [observed heterozygosity (Ho)=0.622±0.022; expected heterozygosity (He)=0.662±0.023; number of alleles (Na)=5.71±1.63; and allelic richness (Ar)=4.097±0.958]. The lowest value of Ho was observed in NEL (0.569±0.019) and the highest in BRH (0.688±0.015). Lowest value of He was also observed in NEL (0.612±0.024) and the highest in BRH (0.700±0.020). Gyr, GUZ and NEL showed high estimations of inbreeding, 9.98, 7.92 and 6.83% respectively. Values of Na varied between 4.93±1.52 in GUZ and 7.04±1.99 in BRH and the Ar values ranged between 3.687±0.895 in NEL and 4.42±1.91 in SIN. On the other hand, although phenotypically, the five breeds are clearly distinguishable, the genetic analysis of structure and kinship demonstrates a total independence among GYR, GUZ and NEL, while BRH and Red Sindhi show a closed relationship. These facts support that GYR, GUZ and NEL have had a diverse origin but also different models of introgression in America. Brahman and SIN could be explained by the intervention of the Sindhi ancestors in the formation of the American synthetic Brahma. © A. Villalobos-Cortés et al., 2015. Source


Martinez A.M.,University of Cordoba, Spain | Gama L.T.,Instituto Nacional dos Recursos Biologicos | Gama L.T.,University of Lisbon | Canon J.,Complutense University of Madrid | And 24 more authors.
PLoS ONE | Year: 2012

Background: American Creole cattle presumably descend from animals imported from the Iberian Peninsula during the period of colonization and settlement, through different migration routes, and may have also suffered the influence of cattle directly imported from Africa. The introduction of European cattle, which began in the 18th century, and later of Zebu from India, has threatened the survival of Creole populations, some of which have nearly disappeared or were admixed with exotic breeds. Assessment of the genetic status of Creole cattle is essential for the establishment of conservation programs of these historical resources. Methodology/Principal Findings: We sampled 27 Creole populations, 39 Iberian, 9 European and 6 Zebu breeds. We used microsatellite markers to assess the origins of Creole cattle, and to investigate the influence of different breeds on their genetic make-up. The major ancestral contributions are from breeds of southern Spain and Portugal, in agreement with the historical ports of departure of ships sailing towards the Western Hemisphere. This Iberian contribution to Creoles may also include some African influence, given the influential role that African cattle have had in the development of Iberian breeds, but the possibility of a direct influence on Creoles of African cattle imported to America can not be discarded. In addition to the Iberian influence, the admixture with other European breeds was minor. The Creoles from tropical areas, especially those from the Caribbean, show clear signs of admixture with Zebu. Conclusions/Significance: Nearly five centuries since cattle were first brought to the Americas, Creoles still show a strong and predominant signature of their Iberian ancestors. Creole breeds differ widely from each other, both in genetic structure and influences from other breeds. Efforts are needed to avoid their extinction or further genetic erosion, which would compromise centuries of selective adaptation to a wide range of environmental conditions. © 2012 Martínez et al. Source


Villalobos-Cortes A.,Institute Investigacion Agropecuaria | Martinez A.,University of Cordoba, Spain | Vega-Pla J.L.,Laboratorio Of Investigacion Aplicada | Landi V.,University of Cordoba, Spain | And 8 more authors.
Pesquisa Agropecuaria Brasileira | Year: 2012

The objective of this work was to establish the genetic relationship between Guabalá and Guaymi cattle populations and some native ones of Latin America. Factorial correspondence analysis, analysis of molecular variance, genetic distances, average number of migrants per population and Wright's F statistics were performed. Population structure was assessed by a Bayesian model, assuming an unknown number of K genetically distinct groups. The correspondence analysis showed that the populations of Guabalá and Guaymí cluster with Mexican creole cattle and Texas Longhorn. Lower genetic differentiation of Panamanian creole with Mexican and Texas Longhorn was also observed. The analyses of genetic distances have also shown similar results to those obtained by Amova and by the factorial correspondence analysis, and the less distance was observed between north populations and Panamanian ones, in comparison with southern populations. Bayesian clustering permitted the assignment of individuals to their respective groups, based on their genetic similarity, and provided information on the number of cluster from which they originate. There is a close historical, genetic, and geographic relationship of Panamanian, Mexican, and Texas Longhorn populations due to the migration of precursors from the Caribbean islands to Panama and Mexico. Source


Villalobos Cortes A.I.,Institute Investigacion Agropecuaria | Martinez A.M.,University of Cordoba, Spain | Escobar C.,Institute Investigacion Agropecuaria | Vega-Pla J.L.,Laboratorio Of Investigacion Aplicada | Delgado J.V.,University of Cordoba, Spain
Livestock Science | Year: 2010

A total of 61 individuals belonging to the Guaymi (GY) and Guabala (GUA) populations were typed with 27 microsatellites. A mean of 5.61 (GUA) and 7.5 (GY) alleles per population was typed, and Fis values were 0.053 (GUA) and 0.033 (GY). The exclusive alleles of each population were 67 (GY) compared to the 16 observed in the GUA population, while 135 alleles are shared by both. The Ho and He were 0.628 (GUA) and 0.710 (GY) and 0.648 (GUA) and 0.724 (GY) respectively. The fixation index Fst was 0.068 demonstrating a moderate level of genetic differentiation. The effective number of migrants per generations was 3.40 between GY and GUA. A comparison with most popular breeds in Panama Bos indicus (GYR, BRH, SIN, GUZ and NEL) and Bos taurus (FRI, SPA and HER) was made because of possible crossbreeding. The AMOVA and a NeighborNet tree performed, provided a detailed interrelationship network, and show an important difference between Panama creoles cattle population and most popular breeds. Strategies for preserving the original Panama cattle creole population should be considered in order to prevent the breed from becoming extinct and to strengthen the breed's capability in future breeding programs. © 2010 Elsevier B.V. All rights reserved. Source

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