Andréa Alves do Egito

Características corporais associadas com a adaptação ao calor em bovinos naturalizados brasileiros

The aim of this work was to evaluate physical aspects of heat tolerance in cattle. Sixty-four animals from five naturalized breeds were used, including Curraleiro (15 animals), Mocho Nacional (7), Crioulo Lageano (17), Pantaneira (14) and Junqueira (11), as well as twenty-six animals from two commercial breeds: Nellore (15) and Holstein (11). Measurements on shoulder height, girth, body length, cannon bone circumference, skin and hair thickness were analysed as well as hair density and hair and skin pigmentation. Girth in Curraleiro was significantly smaller than in other breeds, especially Mocho Nacional. Crioulo Lageano and Pantaneira had the thickest hair and Mocho Nacional the thickest skin. Curraleiro and Junqueira were shown to be the most heat tolerant of the naturalized breeds.

Genetic diversity and population structure of Brazilian native bovine breeds

Estrategias para conservacao e melhoramento animal devem ser baseadas na associacao de caracteristicas fenotipicas e geneticas. O objetivo deste trabalho foi caracterizar cinco racas nativas brasileiras (Caracu, Crioulo Lageano, Curraleiro, Mocho Nacional e Pantaneiro) e duas comerciais (Holandes e Nelore) pela tecnica de RAPD para estimar a distância genetica e a variabilidade genetica entre e dentro das racas. As relacoes geneticas foram investigadas utilizando-se 22 primers, que geraram 122 bandas polimorficas. A analise de variância molecular revelou que a maior parte da variabilidade genetica total ocorreu em virtude das diferencas de individuos dentro das populacoes. Na comparacao da variabilidade genetica entre os pares de racas, observou-se que todos os valores obtidos foram estatisticamente significativos. A menor divergencia genetica foi observada entre Crioulo Lageano e Curraleiro. A raca Mocho Nacional, apesar de historicamente ser considerada de origem Bos taurus aquitanicus,mesma origem da raca Caracu, agrupou-se com as demais racas nativas consideradas de origem Bos taurus ibericus. Demodo geral, as racas estudadas se agruparam em clustersdistintos, com excecao da Mocho Nacional. A tecnica de RAPD foi capaz de distinguir geneticamente as racas estudadas; Caracu, Crioulo Lageano, Curraleiro e Pantaneiro podem ser consideradas entidades geneticas distintas, comprovando assim, a unicidade de suas populacoes; a Mocho Nacional nao conseguiu se restabelecer, apos seu declinio na decada de 50, perdendo, sua identidade genetica.

Genetic characterization of the Moxotó goat breed using RAPD markers

The objective of this study was to verify the genetic diversity between and within seven populations of Moxoto goat (n = 264) from the States of Pernambuco, Paraiba and Rio Grande do Norte, using RAPD (Random Amplified Polymorphic DNA). Moxoto, as well as other naturalized breeds, suffers genetic losses due to the indiscriminate miscegenation with breeds raised in the Northeast Region of Brazil. The genetic characterization of these genetic resources is essential to conservation and breeding programs. DNA was extracted from lymphocytes using a non-organic protocol. The 16 primers used were selected from 120 decamer oligonucleotide primers and generated 56 polymorphic bands. The analysis of molecular variance (AMOVA) showed that the greater part of total genetic variability (71.55%) was due to differences between individuals within populations, while 21.21% was among populations. The analysis of variance among the pairs of populations demonstrated that the populations located in Floresta, PE x Angicos, RN presented a smaller value of intrapopulational differentiation (8.9%), indicating low genetic variability among them. Neis genetic distances varied between 0.0546 and 0.1868 in the populations. The dendrogram generated showed that the Caninde breed, used as outgroup, clustered with the populations of Moxoto, indicating a possible common origin of the naturalized goat breeds.

Caracterização genética da raça bovina Crioulo Lageano usando marcadores moleculares RAPD

The objective of this study was to characterize genetically the Crioulo Lageano cattle breed, using RAPD markers and compare it to the Holstein and Nelore breeds. Forty three primers were selected, and they generated 77 polymorphic bands. Seven groups were studied: 5 subgroups of Crioulo Lageano (I to V) and one each Holstein (VI) and Nellore (VII). Using all groups, the greater part of the genetic variance (65.05%) was due to differences within groups and the rest due to differences between groups. Using five Crioulo Lageano groups (I to V) the results showed 25.28% variation between groups and 74.72% within groups. Genetic diversity has been maintained throughout the generations in this conservation nucleus. The Holstein breed presented the lowest genetic diversity (0.1204) while the Crioulo Lageano herd presented the highest (0.3154). The observed genetic differences were highest between Nellore and Holstein breeds (0.3747), as expected. In general, the Crioulo Lageano groups formed distinct groups and only a few animals from one group were positioned within another group. The RAPD marker technique is adequate to estimate genetic distances between breeds and populations, as well as for use in the choice of individuals for breeding within populations, for conservation of genetic resources.

Genetic variability of Pantaneiro horse using RAPD-PCR markers

Blood samples were collected from Pantaneiro Horses in five regions of Mato Grosso do Sul and Mato Grosso States. Arabian, Mangalarga Marchador and Thoroughbred were also included to estimate genetic distances and the existing variability among and within these breeds by RAPD-PCR (Random Amplified Polymorphic DNA - Polymerase Chain Reaction) molecular markers. From 146 primers, 13 were chosen for amplification and 44 polymorphic bands were generated. The analysis of molecular variance (AMOVA) indicated that the greatest portion of detected variability was due to differences between individuals within populations (75.47%). Analysis of the genetic variability between pairs of populations presented higher estimates for the five Pantaneiro populations with the Arabian breed, while lowest estimates were presented by pairs formed among the Pantaneiro populations with the Mangalarga Marchador. Highest genic diversity was shown by the Pantaneiro (0.3396), which also showed highest genetic distance with the Arabian and lowest with Mangalarga Marchador breed. UPGMA dendrogram showed distinct differences between naturalized (Pantaneiro and Mangalarga Marchador) and exotic (Arabian and Thoroughbred) breeds. In the dendrogram generated by UPGMA method, the similarity matrix generated by the Jaccard coefficient showed distinction between the naturalised breeds, Pantaneiro and Mangalarga Marchador, and the exotic breeds, Arab and English Thoroughbred. Results suggest that the Pantaneiro presents a higher genetic variability than the other studied breeds and has a close relationship with the Mangalarga Marchador.

Transfer of passive immunity and serum proteinogram in the first six months of life of Criollo Lageano and black and white holstein calves

The objective of this study was to evaluate and compare the transfer of passive immunity and the proteinogram in Criollo Lageano (CL) and Black and White Holstein (BWH) calves. Two groups were utilized with 13 Criollo Lageano and 10 BWH calves. Blood samples were collected for the measurement of total serum protein, electrophoresis of serum proteins, activity of the gamma glutamyl transferase, and concentration of IgG by the method of the zinc sulfate turbidity in periods between 24 and 36 hours of life, 15, 30, 60, 90, 120, 150 and 180 days. Statistical analysis was performed by ANOVA and Tukey test at 5% significance level, and correlations between variables were calculated. Variations of serum proteins followed a pattern of physiological behavior over the first six months of life and production of immunoglobulins was active earlier in BWH calves and slower in the Criollo Lageano, without causing any impact on their health. Gamma globulin in the first days of life (24-36h) was correlated with IgG (r=0.87 for CL and r=0.89 for BWH), PTS (r=0.91 for CL and r=0.92 for BWH), Glob (r=0.99 for CL and r=0.98 for BWH) and GGT (r=0.14 for CL and r=0.83 for BWH). It was concluded that there was no failure in the transfer of passive immunity in Criollo Lageano calves but this failure occurred in the BWH calves. IgG values estimated by the zinc sulfate turbidity and serum proteins were considered good indicators of the transfer of passive immunity in calves between 24 and 36 hours of life.

Heat Tolerance in Curraleiro Pe-Duro, Pantaneiro and Nelore Cattle Using Thermographic Images

The objective of this study was to compare physiological and thermographic responses to heat stress in three breeds of cattle. Fifteen animals of each of the Nelore, Pantaneiro and Curraleiro Pe-Duro breeds, of approximately two years of age, were evaluated. Heart and respiratory rates, rectal and surface temperature of animals as well as soil temperature were recorded at 8:30 and 15:30 on six days. Variance, correlation, principal factors and canonical analyses were carried out. There were significant differences in the rectal temperature, heart and respiratory rate between breeds (p < 0.001). Nelore and Pantaneiro breeds had the highest rectal temperatures and the lowest respiratory rate (p < 0.001). Breed was also significant for surface temperatures (p < 0.05) showing that this factor significantly affected the response of the animal to heat tolerance in different ways. The Curraleiro Pe-Duro breed had the lowest surface temperatures independent of the period evaluated, with fewer animals that suffered with the climatic conditions, so this may be considered the best adapted when heat challenged under the experimental conditions. Thermography data showed a good correlation with the physiological indexes, and body area, neck and rump were the main points.

Genetic diversity, population structure, and correlations between locally adapted zebu and taurine breeds in Brazil using SNP markers

Genetic diversity is one of the most important issues in studies on conservation of cattle breeds and endangered species. The objective of this study was to estimate the levels of genetic differentiation between locally adapted taurine (Bos taurus taurus) and zebu (Bos taurus indicus) breeds in Brazil, which were genotyped for more than 777,000 SNPs. The fixation index (FST), principal component analysis (PCA), and Bayesian clustering were estimated. The FST highlighted genetic differentiation between taurine and zebu breeds. The taurine lines, Caracu and Caracu Caldeano, had significant genetic differentiation (FST close to 5%) despite their recent selection for different uses (meat and milk). This genetic variability can be used for conservation of locally adapted animals, as well as for breeding programs on zebu breeds. Introgression of zebu in locally adapted breeds was identified, especially in Curraleiro Pé-Duro breed. The Gyr breed, however, had low breed purity at genomic level due to its very heterogeneous mixing pattern.

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.

Growth curve of locally adapted pantaneiro cows raised under natural conditions

The objective of this study was to use morphometric and ultrasound evaluations to estimate the growth curve of the Pantaneiro cattle breed, raised in its natural habitat, aiming at the re-insertion of this breed in production systems. One hundred and three females, aging from months to 11 years, and raised on native pastures, were evaluated. The animals belonged to the Conservation Nucleus of Embrapa Pantanal, located in the Pantanal of Mato Grosso do Sul (Brazil). Weight, thoracic perimeter (TP), body length (BL), rump height (RH), height at withers (HW), hip height (HH), depth (DP), distance between the ilia (DI) (cm) and rib-eye area (REA) were measured. To relate the measurements with the age of the animals, the univariate regression model was used, assigning the variable response to gamma distribution. The Pearson correlation between variables was also estimated. The inflection point of the growth curve was 37 months for HH; between 38 and 39 months for TP and HW; between 40 and 41 months for DI, HH and DP; and 45 months for BL. The REA results could not fit in a statistical model. The majority of the variables presented a correlation above 60% among themselves, except for REA × Age, of 15.81%; REA × HW, of 34.44%; HH × Age, of 46.19; HH × DI, of 58.07%; REA × HH, of 24.57%; and REA × TP, of 39.9%. The cows showed maturity age at 40 months, which may have occurred because they were raised in natural farming conditions. In Pantaneiro cows reared in extensive systems only on natural pastures, the use of ultrasound is not effective to estimate the curve of muscular development, perhaps because this breed was not selected for weight gain.