Théa Mírian Medeiros Machado

Genetic diversity between herds of Alpine and Saanen dairy goats and the naturalized Brazilian Moxotó breed

Brazilian naturalized goat breeds are adapted to the semiarid conditions prevalent in the Northeast region of the country (which has the largest Brazilian goat heard) and represent an as yet uninvestigated source of genetic diversity. Currently, imported goat breeds are crossed with Brazilian naturalized goat breeds, endangering the genetic potential of the naturalized breeds. We used 11 microsatellite markers to determine the genetic diversity among imported (non-naturalized) dairy Alpine and Saanen goats and naturalized Brazilian Moxoto goats. We genotyped 292 goats from three herds (one private, one from the University of Minas Gerais and the Moxoto conservation herd from Embrapa Caprinos) and found that the general heterozygosity was 0.6952 for Alpine, 0.7043 for Saanen and 0.4984 for Moxoto goats. The number of alleles ranged from 5 (INRA005) to 11 (BM3205), with an average of 7 alleles per locus in the imported breeds and 3.5 alleles per locus in the Moxoto breed. Mean differentiation between populations was higher for herds (FSTS = 0.0768) than for breeds (FSTP = 0.0263), indicating similarity between the imported breeds and the existence of crosses between them. Neis genetic distance was highest between the Moxoto breed and the imported breeds. These indicate that further studies using these molecular markers would be fruitful.

Structure and genetic relationships between Brazilian naturalized and exotic purebred goat domestic goat (Capra hircus) breeds based on microsatellites

The genetic relationships and structure of fourteen goat (Capra hircus) populations were estimated based on genotyping data from 14 goat populations (n = 410 goats) at 13 microsatellite loci. We used analysis of molecular variance (AMOVA), principal component analysis (PCA) and F statistics (FIS, FIT and FST) to evaluate the genetic diversity (Ho, He and ad) of the goats. Genetic distances between the 14 goat populations were calculated from allelic frequency data for the 13 microsatellite markers. Moderate differentiation was observed for the populations of the undefined breeds (including the Anglo-Nubian-M breed), the naturalized Brazilian breeds (Moxoto, Caninde), the exotic purebred breeds (Alpine, Saanen, Toggenbourg and Anglo-Nubian) and the naturalized Brazilian Grauna group. Our AMOVA showed that a major portion (88.51%) of the total genetic variation resulted from differences between individual goats within populations, while between-populations variation accounted for the remaining 11.49% of genetic variation. We used a Reynolds genetic distance matrix and PCA to produce a phenogram based on the 14 goat populations and found three clusters, or groups, consisting of the goats belonging to the undefined breed, the naturalized breeds and the exotic purebred breeds. The closer proximity of the Caninde breed from the Brazilian state of Paraiba to the Grauna breed from the same state than to the genetically conserved Caninde breed from the Brazilian state of Ceara, as well as the heterozygosity values and significant deviations from Hardy-Weinberg equilibrium suggests that there was a high number of homozygotes in the populations studied, and indicates the importance of the State for the conservation of the local breeds. Cataloguing the genetic profile of Brazilian goat populations provides essential information for conservation and genetic improvements programs.

Relationship among the economically important ratites: a clustering approach based on their reproductive biology

Objetivou-se avaliar o efeito de diferentes doses de dejeto liquido de suinos sobre a taxa de acumulo de materia seca e o valor nutritivo (proteina bruta e fibra em detergente neutro) de uma pastagem de capim-tifton 85 cultivada na regiao sudoeste do Parana no periodo de outubro de 2005 a marco de 2006. Utilizou-se delineamento experimental de blocos ao acaso em esquema fatorial de 4 x 4, composto por quatro doses de dejetos liquidos de suinos nas parcelas (0, 80, 160 e 320 m3/ha) e quatro cortes consecutivos nas subparcelas da pastagem. Foram realizadas duas aplicacoes, uma no inicio do experimento e outra 80 dias apos. Os cortes foram realizados sempre que a altura da pastagem atingisse 40 cm. Houve interacao dose versus corte para todas as variaveis. Os dejetos promoveram aumento na taxa de acumulo de materia seca somente no primeiro corte apos sua aplicacao (cortes 1 e 3). O rendimento maximo de materia seca (24,2 t/ha) foi obtido na dose de 249 m3/ha de dejetos (143 e 106 m3/ha, respectivamente, para as aplicacoes 1 e 2), correspondentes a 450 kg/ha de nitrogenio. O percentual de proteina bruta aumenta e o de fibra em detergente neutro do capim-tifton 85 diminui com o aumento da dose de dejetos, melhorando o valor nutritivo da forragem. A eficiencia de utilizacao e a taxa de recuperacao do nitrogenio diminuem com o incremento da dose de dejetos liquido de suinos.

Cluster evaluation of Brazilian and Moroccan goat populations using physical measurements

The aim of this study was to compare the genetic diversity of 12 populations of goats in Brazil and Morocco (n = 796) through the use of physical measurements and different multivariate techniques. Traits measured included wither height (WH), distance from the brisket to the ground (BH) and ear length (EL). The standardized Euclidean distance (D) was adopted. The D values were submitted to clustering analysis using hierarchical methods (from nearest neighbor and UPGMA - Unweighted Pair Group Method with Arithmetic Mean) and the numbers of clusters were analyzed using the Tocher optimization method. The population clustering was different depending on the method of analysis used. Among the hierarchical methods, UPGMA showed the best fit (CCC = 0.82). The Tocher method enabled the formation of four different clusters. Although the hierarchical and Tocher methods resulted in different cluster formations, both contributed to the interpretation of the genetic cluster divergence. The results obtained through UPGMA and Tocher optimization enable their use for future studies that may include a larger number of biometric variables on greater numbers of individuals and additional populations.

Biometric variability of goat populations revealed by means of principal component analysis

The aim was to analyze variation in 12 Brazilian and Moroccan goat populations, and, through principal component analysis (PCA), check the importance of body measures and their indices as a means of distinguishing among individuals and populations. The biometric measurements were wither height (WH), brisket height (BH) and ear length (EL). Thorax depth (WH-BH) and the three indices, TD/WH, EL/TD and EL/WH, were also calculated. Of the seven components extracted, the first three principal components were sufficient to explain 99.5% of the total variance of the data. Graphical dispersion by genetic groups revealed that European dairy breeds clustered together. The Moroccan breeds were separated into two groups, one comprising the Drâa and the other the Zagora and Rhâali breeds. Whereas, on the one side, the Anglo-Nubian and undefined breeds were the closest to one another the goats of the Azul were observed to have the highest variation of all the breeds. The Anglo-Nubian and Boer breeds were similar to each other. The Nambi-type goats remained distinct from all the other populations. In general, the use of graphical representation of PCA values allowed to distinguish genetic groups.

Técnicas de avaliação dos valores energéticos e dos coeficientes de digestibilidade de alguns alimentos para emas (Rhea americana) em crescimento

Avaliaram-se os valores de energia metabolizavel aparente e aparente corrigida (EMA e EMAn, respectivamente), os coeficientes de metabolizacao da energia bruta (CMEB e CMEBn) e da digestibilidade da MS e MO (CDAMS e CDAMO) de alguns alimentos para emas (Rhea americana) de sete meses de idade, utilizando-se as tecnicas de coleta total de excretas e do oxido de cromo como indicador. Utilizou-se o delineamento experimental inteiramente ao acaso, em esquema de parcelas subdivididas, com seis tratamentos, cada um com tres repeticoes. O experimento foi realizado tres vezes, sequencialmente. Os valores dos CDAMS, CDAMO, EMA, EMAn, CMEB e CMEBn dos alimentos, determinados por meio da tecnica de coleta total de excretas, foram, de modo geral, superiores aos determinados pela tecnica do oxido de cromo. A tecnica do oxido de cromo mostrou-se inadequada para determinar os CDAMS, CDAMO, EMA, EMAn, CMEB e CMEBn dos alimentos para emas em comparacao a tecnica de coleta total de excretas. Recomenda-se a realizacao de ensaios similares envolvendo outras tecnicas indiretas para estimar parâmetros de digestibilidade nesta especie.

Inventário e caracterização morfológica de caprinos Gurgueia no Estado do Piauí

The purpose of this study was to conduct the inventory of goat breed Gurgueia in the state of Piaui, Northeast region of Brazil. The inventory includes a historical survey - made by searching in the literature - and a population survey - made by gathering in loco information. The geographic location through GPS was taken in farms sheltering Gurgueia goats and then individuals Gurgueia were counted to estimate population size and classifying the risk of extinction. To characterize the Gurgueia breed, the presence of beard, horns, earrings, patterns of color roan, agouti and brown, and the presence of reduced ear were observed to perform simple descriptive analysis. The regional literature demonstrates lack of consistency about the origin of the Gurgueia breed. However, flocks of goats in the Gurgueia river valley, in Southern Piaui, gave origin to the breed denomination. The present study found out 119 Gurgueia individuals scattered in three micro-regions - classifying the Gurgueia breed as critically endangered. The morphological analysis shows low frequency of earrings (0,05) and high frequency of horn (0.95) in Gurgeia individuals. The beard frequency was 0.52 and was verified absence of long hairs, indicating no relationship between those. The analysis showed high frequency of roan pattern (0.96), absence of brown and single coat pattern (non-agouti). Reduced ear was absent. This inventory appointed that Gurgueia risk of endangerment is unstable, since its presence within herds is mixed with other breed types.

Genetic diversity of captive spotted paca (Agouti paca) from south east Brazil assessed by the RAPD-PCR technique

The genetic diversity was analyzed among spotted paca (Agouti paca) from three commercial flocks located in Brazil. As the genome of this species is unknown, the RAPD-PCR technique was used. Ten primers generated sixty polymorphic bands. The among and within population genetic variability estimated by analysis of molecular variance (AMOVA) was 12.55 and 87.45%, respectively. The shortest Nei distance value was 11.76% among the Carangola (CG) and Sao Francisco do Gloria (SF) populations. This value can be explained by the exchange of reproduction males and females between the two geographically close breeding sites. The analysis of principal components showed well defined and structured groups aggregating animals according their population of origin, with some exceptions. Lower diversity was found in the Sao Francisco population than in the Carangola and Castelo (CS) populations. This result suggested the variability is better conserved in breeding farms with fifty or sixty animals (CG and CS) than in the breeding farm with a dozen animals (SF). The RADP-PCR technique proved to be informative for the quantification of among and within population genetic variability of the spotted paca. The phenogram generated by UPGMA using the NTSYS-PC software from the Nei Distance, grouped CG and SF on a single branch connected to the CS, with 76 and 100% accuracy, respectively, to the bootstrap. This result was not only consistent with the historical and geographical information on flocks, but also shows the need for periodic reproductive male replacement. Future studies should be developed with co-dominant markers and include spotted paca from more distant places.