Genetic analysis of loci affecting production and reproduction traits in livestock animals make possible the evaluation of animal breeding values using molecular markers. The aim of this study was to detect polymorphisms in the leptin and k-casein genes of a Cuban water buffalo population to provide markers useful for associating studies. Genomic DNA from 68 unrelated Cuban buffaloes, uncontrolled crossbreds of river (Buffalypso) and swamp (Carabao) animals, was analyzed using PCR-RFLP. Fragments of leptin and ê-casein genes were amplified and digested with Bsa AI and Hind III/Taq I, respectively. All the amplified samples were monomorphic BB after digestion with Hind III/Taq I. Genotypic frequencies found in the leptin gene with Bsa AI were 0.47 (AA), 0.42 (AG) and 0.11 (GG). The population was in HWE (p=1.0000), possibly because there was not selection for this locus on it. The F IS estimate (0.0212) showed no inbreeding in the population regarding this locus. He (0.436) and Ho (0.426) values were below 0.5 (50%), indicating low genetic variation in this locus in the population. PCR-RFLP detected the two genetic variants described for the leptin gene A1620G. However, a higher number of animals and SNPs in the leptin and/or other genes should be analyzed for a more accurate estimate of the genetic diversity in this population. DNA sequencing should be assayed by nucleotide sequence analysis to detect the new A and B variants of k-casein reported in buffalo.

El análisis genético de loci, que controla caracteres productivos y reproductivos, hace posible la evaluación del valor genético en el ganado con el uso de marcadores moleculares. El objetivo de este estudio fue detectar polimorfismos en los genes de la leptina y la k-caseína en búfalos cubanos, para proveer marcadores útiles en estudios de asociación. Se amplificaron por PCR fragmentos de los genes de la leptina y la ê-caseína que se digirieron con Bsa AI y Hind III/Taq I, respectivamente. Todas las muestras amplificadas resultaron monomórficas BB tras la digestión con Hind III/Taq I. Las frecuencias genotípicas en el gen de la leptina fueron, 0.47 (AA), 0.42 (AG) y 0.11 (GG). La población se encontró en equilibrio de Hardy-Weinberg (p=1.0000), posiblemente, porque no está ocurriendo selección para dicho locus. El F IS estimado (0.0212) mostró que no existe endogamia en la población cuando se considera este locus. Los valores de He (0.436) y Ho (0.426) estaban por debajo de 0,5 (50%), lo que indica que existe una baja variabilidad genética para este locus en la población. La PCR-RFLP permitió detectar las variantes genéticas descritas para A1620G en el gen de la leptina. Sin embargo, se deben analizar un mayor número de animales y SNPs, en este u otros genes, para estimar con mayor certeza la diversidad genética en esta población. Es necesario el uso de la secuenciación para detectar las nuevas variantes A y B de la k-caseína que se han descrito en búfalos a través de esta técnica.

Researches on genetic relationships among water buffalo populations are useful in supporting conservation decisions and designing of breeding schemes. The aim of this study was to assess the genetic relationships among Cuban Buffalypso/Carabao hybrids and Murrah and Jaffarabadi Brazilian buffaloes using nine cattle microsatellite markers. During the analysis, four loci were excluded due to the presence of null alleles, stuttering and gametic disequilibrium. Mean numbers of alleles and the heterozygosities observed and expected in the three populations were not significantly different. Heterozygosities found were above 60%. All five loci were in Hardy-Weinberg equilibrium. Wright´s index for estimating inbreeding were negative in the three populations. A moderate population differentiation was found among Cuban and Brazilian populations. The AMOVA showed that only 8.3% of the total variation observed occurred among breeds (P<0.05). The multivariate factorial correspondence analysis showed low breed-specific clustering and most of Murrah and Jaffarabadi Brazilian animals plotted overlapping. UPGMA dendrogram obtained from Nei's D A genetic distance differentiated two clusters, one grouped Cuban buffaloes (bootstrap value 89%), and the other included the Brazilian populations (bootstrap value 100%). Bayesian clustering approach reinforced the previous results. The origin of Buffalypso breed and its genetic management in Cuba could be the reason to the moderate differentiation between Cuban and Brazilian populations. This study provided a preliminary analysis on genetic relationships between Cuban and Brazilian buffaloes. The research must be extended to include a higher number of microsatellite loci and buffalo populations from other geographical regions of each country.

Las investigaciones sobre relaciones genéticas entre poblaciones de búfalos de agua son fundamentales para las decisiones relacionadas con la conservación y el diseño de esquemas de mejora. El objetivo de este trabajo fue estimar las relaciones genéticas entre búfalos de Cuba y de Brasil a través de nueve marcadores microsatélites. Se excluyeron del análisis cuatro loci por presencia de alelos nulos, posibles errores de lectura por tartamudeo de las bandas y desequilibrio gamético. No se encontraron diferencias significativas entre las medias del número de alelos y las heterocigosidades observadas y esperadas en las tres poblaciones. Los niveles de heterocigosidad encontrados están por encima del 60%. Los cinco loci se hallaban en equilibrio de Hardy-Weinberg. El índice de Wright para estimar la endogamia de la población fue negativo en las tres. Se estimó una diferenciación moderada entre las poblaciones de búfalos de Cuba y de Brasil. El AMOVA mostró que solo el 8.3% de la variación total observada estaba entre las razas. En el análisis factorial de correspondencia se observó una baja especificidad en el agrupamiento en razas y una ubicación sobrelapada de la mayoría de los animales brasileños. El dendograma UPGMA, a partir de la distancia genética de Nei (D A), mostró dos grupos: uno agrupó a los búfalos cubanos y el otro incluyó a las poblaciones brasileñas. El agrupamiento por métodos bayesianos reforzó los resultados previos. El origen de la raza Buffalypso y su manejo genético en Cuba pueden ser las razones de la moderada diferenciación entre las poblaciones de búfalos de Cuba y de Brasil. Estos resultados constituyen un análisis preliminar de las relaciones genéticas entre búfalos de Cuba y de Brasil. La investigación debe ser ampliada para analizar un mayor número de loci microsatélite, así como para incluir más poblaciones de otras regiones geográficas en cada país.

<p>Objetivou-se caracterizar o genótipo da kappa-caseína em 144 vacas Girolando, do Estado de Pernambuco, utilizando a técnica de PCR-RFLP. Foram coletadas amostras de sangue total desses animais dos seguintes grupos genéticos: 30 ½ holando-gir, 38 ¾ holando-gir e 76 ⅝ holando-gir. Desse material foi extraído o DNA. Através do DNA foi determinada uma região que foi amplificada e seu produto sofreu ação da enzima de restrição HindIII para observar os possíveis polimorfismos. Foram encontrados os seguintes genótipos com respectivas frequências: AA (0,59); AB (0,25) BB (0,06); AC (0,05); BC (0,02) e CC (0,02). As frequências alélicas observadas para os genes A, B e C foram 0,74; 0,20 e 0,06, respectivamente. Há de se registrar a detecção do gene C na população, raramente descrito em outros trabalhos. A presença do genótipo BB na população de vacas holando-gir aponta para implantação de programas de seleção genética visando aumento na frequência do genótipo em questão, o que possibilitará ganhos significativos na cadeia do leite, particularmente, para produtores e indústrias de processamento.</p>

<p>This study aimed to characterize the genotype of kappa-casein in 144 Gir cows, the State of Pernambuco, using PCR-RFLP. 30 ½ Holstein-gir-gir 38 ¾ Holstein and Holstein-turned 76 ⅝: Whole blood samples of the animals of the following genotypes were collected. This material was extracted DNA. Through a region of DNA was amplified and its product has the action of restriction enzyme HindIII possible to observe the polymorphism was determined. The following genotypes with respective frequencies were found: AA (0.59); AB (0.25) BB (0.06); CA (0.05); BC (0.02) and CC (0.02). The allele frequencies observed for genes A, B and C were 0.74; 0.20 and 0.06, respectively. Important to note the detection of the C gene in the population, rarely described in other papers. The presence of the BB genotype in the population of Holstein cows-turned points for deployment of genetic selection for increased frequency of the genotype in question, which will enable significant gains in the milk chain, particularly for producers and processing industries programs.</p>

This study estimated the genetic diversity and structure of 12 genetic groups (GG) of locally adapted and specialized pigs in the state of Pernambuco using 22 microsatellite markers. Nine locally adapted breeds (Baé, Caruncho, Canastra, Canastrão, Mamelado, Moura, Nilo, Piau and UDB (Undefined Breed)) and 3 specialized breeds (Duroc, Landrace and Large White), totaling 190 animals, were analyzed. The Analysis of Molecular Variance (AMOVA) showed that 3.2% of the total variation was due to differences between genetic groups, and 3.6% to differences between local and commercial pigs. One hundred and ninety eight alleles were identified and apart from the Large White breed, all GG presented Hardy-Weinberg Equilibrium deviations for some loci. The total and effective allele means were lower for Duroc (3.65 and 3.01) and higher for UDB (8.89 and 4.53) and Canastra (8.61 and 4.58). Using Nei's standard genetic distance and the UPGMA method, it was possible to observe that the Landrace breed was grouped with the local genetic groups Canastra, Moura, Canastrão, Baé and Caruncho. Due to the complex admixture pattern, the genetic variability of the 12 genetic groups can be analyzed by distributing the individuals into two populations as demonstrated by a Bayesian analysis, corroborating the results from AMOVA, which revealed a low level of genetic differentiation between the inferred populations.