Heden Luiz Marques Moreira

Temperamento e comportamento materno-filial de ovinos das raças Corriedale e Ideal e sua relação com a sobrevivência dos cordeiros

ABSTRACT The trial was conducted at the ExperimentalStation of Embrapa, Bage, RS, from March 2005 to February2006, and aimed to evaluate the maternal behavior andtemperament of ewes and their lambs and related them withlamb’s survival. Forty-seven Corriedale ewes with mean bodyweight of 52.1kg and 45 Pollwarth ewes with mean body weightof 49.5kg were used, according to a completely randomizeddesign. Temperament was evaluated through maternalbehaviour score (MBS), flight time test (score and quantitative)and flight distance. Corriedale ewes presented larger values forflight time score than Pollwarth ewes. Corriedale lambs wereheavier and a greater number survived than Pollwarth lambs.Sheep breed did not affect maternal score. Ewes consideredreactive (MBS=1, those who run away and did not come backto stay with their lamb) seek less isolation from the herd atparturition, protected less their lambs, weaned them earlierand lighter than less reactive ewes. Reactivity decreasedmaternal care of ewes with its lambs, and this characteristicmight be considered by productive systems.

Microsatellite analysis of the parental contribution of Piaractus mesopotamicus to the production of offspring in the semi-natural system of reproduction

The objective of this study was to evaluate the genetic diversity and the parental contribution of Piaractus mesopotamicus in the production of offspring in the semi-natural system of reproduction. Twenty parental fishes (eleven males and nine females) and the total of 100 larvae were evaluated by microsatellite marker. The parents and offspring had thirty-one alleles and heterozygosity of 0.550 and 0.563, respectively. The females were fertilised by two up to six males while the males fertilised three up to five females. The contribution of the females and males to the offspring were 66.6 and 58%, respectively. Such results indicated no loss in the genetic variability in the offspring, and the parents had multiple paternity and reasonable contribution to the offspring production.

Diversidade genética de dourado utilizado em programas de repovoamento no rio Paranapanema

The objective of this work was to estimate by RAPD markers the genetic diversity of a Salminus brasiliensis lot used in stock enhancement programs in the Paranapanema River, Parana, Brazil. Ten broodstocks (five males and five females) and their progeny (40 larvae and 40 fingerlings) were analyzed. Eight analyzed primers produced 96 fragments, of which 81.2% were polymorphic. There was significant difference in the frequency of 32 out of the 96 fragments, with the presence of an exclusive fragment in the fingerlings. The Shannon index, the percentage of polymorphic fragments, and the genetic distance and identity showed less genetic divergence between broodstocks and larvae, besides a decrease of genetic variability in the fingerlings. Genetic divergence was lower in the fingerlings in comparison to the larvae and broodstocks. The molecular variance results showed that most of the genetic variation is within (90.05%) and not between groups (9.95%). The broodstock lot has high genetic variability, and genetic differences were observed between the larval and fingerling stages.

Utilization of microsatellite markers to form families of "pejerrey" Odontesthes bonariensis in a genetic breeding program

Foram identificadas a divergencia e a variabilidade genetica, por meio do polimorfismo de seis marcadores microssatelites, de duas populacoes de Odontesthes bonariensis, utilizadas em manejos de cultivo e com potencial para fornecimento de reprodutores para programas de melhoramento genetico. Do total de seis loci, cinco demonstraram eficiencia para analise genetica nas duas populacoes de O. bonariensis. A diferenciacao genetica significante nas populacoes analisadas pode fornecer a base para futuros programas de melhoramentos geneticos, atraves da combinacao de material das populacoes divergentes para o desenvolvimento de linhagens ou execucao de um programa de selecao.