Genetic parameter estimates and response to selection for weight and testicular traits in Nelore cattle

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Quantitative trait loci for performance traits in a broiler x layer cross

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Effect of genotype, finishing system, and sex on physiochemical characteristics of goat meat

Foram utilizados 78 cabritos de ambos os sexos e de cinco genótipos: raça Alpina, ½ Boer + ½ Alpina, ¾ Boer + ¼ Alpina, ½ Anglo-nubiana + ½ Alpina e tricross (½ Anglo-nubiana + ¼ Boer + ¼ Alpina), com peso médio inicial de 14,1 ± 2,5 kg. Objetivou-se avaliar os efeitos do genótipo, do sistema de terminação e do sexo sobre as características físico-químicas da carne. Os sistemas de terminação foram constituídos: ST1 - cabrito + mãe em pasto e ST2 - cabrito desmamado confinado. Os cabritos do ST1 foram mantidos em piquetes formados com Panicum maximum cv. Tanzânia e os do ST2 receberam dieta completa com 16% PB e 73% NDT. Os valores de pH, a* (teor de vermelho), Perda de Peso ao Cozimento (PPC) e porcentagem de Extrato Etéreo (EE) foram influenciados pelo genótipo. Os teores de vermelho (a*) e L* (luminosidade), PPC e porcentagens de umidade, proteína, EE e cinzas foram influenciados pelo sistema de terminação. O músculo longissimus dorsidos animais ½ BA apresentou as melhores características físico-químicas. Se a preferência do consumidor for por uma carne mais macia e com maior teor de gordura, as fêmeas são mais indicadas.

Transferência de imunidade passiva em bezerros das raças Nelore e Limousin e proteinograma sérico nos primeiros quatro meses de vida

Com o objetivo de investigar alguns aspectos relacionados à transferência de imunidade passiva em bovinos de corte, foram selecionados 90 bezerros aparentemente sadios, 45 da raça Nelore e 45 da raça Limousin, distribuídos em 3 grupos (com 15 bezerros cada) de acordo com o número de parições de suas mães: primeira cria; segunda cria; e terceira ou mais crias. Amostras de sangue foram colhidas de cada bezerro entre 24 e 36 horas de vida e com 15, 30, 60, 90 e 120 dias. Determinaram-se as concentrações de proteína total no soro (PT) e no plasma (PPT), a atividade sérica da gamaglutamiltransferase (GGT), e as concentrações séricas de albumina, alfa, beta e gamaglobulinas por eletroforese em gel de agarose e de IgG estimada por meio do método de turvação pelo sulfato de zinco. Empregou-se a análise de variância bifatorial para as variáveis mensuradas na primeira colheita. O comportamento das variáveis em função da idade foi estudado por meio da análise de variância de medidas repetidas. Correlações foram estabelecidas entre as variáveis. A transferência de imunidade passiva foi bem sucedida nos bezerros de ambas as raças e o número de parições das mães não interferiu no processo. As concentrações mais elevadas de gamaglobulinas ao término do primeiro dia de vida declinaram até valores mínimos aos 60 dias. A partir dessa idade, a elevação conseqüente à produção ativa de anticorpos foi mais precoce nos bezerros taurinos e mais lenta nos zebuínos. A gamaglobulina, ao término do primeiro dia de vida, correlacionou-se com as seguintes variáveis: IgG (r=0,859), PPT (r=0,807), PT (r=0,811) e GGT (r=0,399). O fator etário exerceu efeito sobre todas as variáveis mensuradas. As variações das proteínas séricas obedeceram a um padrão de comportamento fisiológico ao longo dos quatro primeiros meses de vida, de forma geral, não distinto em taurinos e zebuínos.

Período de absorção intestinal de macromoléculas em cabritos recém-nascidos após a ingestão de colostro bovino

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Clinical assessment of postoperative sensitivity in posterior composite restorations

This incidence of postoperative sensitivity was evaluated in resin-based posterior restorations. Two hundred and ninety-two direct restorations were evaluated in premolars and molars. A total of 143 Class I and 149 Class 11 restorations (MO/OD and MOD) were placed in patients ranging in age from 30 to 50 years. After the cavity preparations were completed, a rubber dam was placed, and the preparations were restored using a total-etch system (Prime & Bond NT) and a resin-based restorative material (TPH Spectrum). The patients were contacted after 24 hours and 7, 30 and 90 days postoperatively and questioned regarding the presence of sensitivity and the stimuli that triggered that sensitivity. The Chi-square and Fisher's Exact Test were used for statistical analysis. Evaluation at 24 hours after restorative treatment revealed statistically significant differences among the types of cavity preparations restored and the occurrence of postoperative sensitivity (p=0.0003), with a higher frequency of sensitivity in Class H MOD restorations (26%), followed by Class II MO/DO (15%) and Class I restorations (5%). At 7, 30 and 90 days after restorative treatment, there was a decrease in the occurrence of sensitivity for all groups. The percentage of sensitivity among the groups was not significantly different. This study shows that the occurrence of sensitivity is correlated with the complexity of the restoration.

Fish ladders select fish traits on migration - still a growing problem for natural fish populations

We investigated the potential selective effect of fish ladders on physiological and morphological profiles of the curimbata, Prochilodus lineatus, during reproductive migration in Brazil. We registered sex, body weight and length, plasma glucose, hepatosomatic and gonadosomatic indices (HSI and GSI, respectively), hematocrit, leucocrit, blood cell and nucleus areas, and the diameter of white and red muscle fibers in fish sampled at the bottom (downstream) and at the top (upstream) of a fish ladder at a hydroelectric dam. Males and females at the top of the ladder showed higher size (weight and length), white muscle fiber diameters, plasma glucose levels and lower hematocrit when compared with those at the bottom. These size and muscle traits assist fish to overcome the ladder barrier and bypass the dam, an effort that might be reflected in the glucose levels. Females also showed higher GSI at the top of the fish ladder, a trait possibly facilitating their reproduction upstream. These results indicate that a dam system favors fish with specific morphological-physiological profile. This may have a strong influence upon upstream fish populations over generations and implies the presence of artificial selective pressure.

Genetic diversity in Egeria densa and E. najas in Jupia Reservoir, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

PCR primed with minisatellite core sequences yields species-specific patterns and assessment of population variability in fishes of the genus Brycon

Minisatellite core sequences were used as single primers in polymerase chain reaction (PCR) to amplify genomic DNA in a way similar to the random amplified polymorphic DNA methodology. This technique, known as Directed Amplification of Minisatellite-region DNA, was applied in order to differentiate three neotropical fish species (Brycon orbignyanus, B. microlepis and B. lundii ) and to detect possible genetic variations among samples of the threatened species, B. lundii , collected in two regions with distinct environmental conditions in the area of influence of a hydroelectric dam. Most primers generated species-specific banding patterns and high levels of intraspecific polymorphism. The genetic variation observed between the two sampling regions of B. lundii was also high enough to suggest the presence of distinct stocks of this species along the same river basin. The results demonstrated that minisatellite core sequences are potentially useful as single primers in PCR to assist in species and population identification. The observed genetic stock differentiation in B. lundii associated with ecological and demographic data constitute a crucial task to develop efficient conservation strategies in order to preserve the genetic diversity of this endangered fish species.

Assessment of the ichthyofauna in stretches under the influence of Salto Grande Reservoir (Middle Paranapanema River, SP/PR, Brazil).

Aim: To analyze the composition, species richness and spatial distribution of the fish fauna in the area under influence of the Salto Grande Reservoir; Methods: Fish were caught every two months from November/05 to October/06, using gill nets, seining nets and sieve; Results: It was registered 67 fish species, 1,964 individuals and 146.2 kg, representing CPUEn of 1,964 and CPUEb of 278 kg. The most representative orders were Characiformes, with 29 species, Siluriformes (21 species) and Perciformes (11 species) Nine non-native species were registered. The most abundant species in the reservoir were Astyanax altiparanae, Steindachnerina insculpta and Acestrorhynchus lacustris, indicating the predominance of medium and small fishes in this reservoir. The dendrogram of similarity separated the Dam and Pedra Branca stretches from Pardo River Mouth, indicating differences in the assemblages. The species turnover among the stretches was demonstrated by the beta diversity, which may be related to the diversity of habitat; Conclusions: Although being a small reservoir, it displays great habitat diversity, reflecting in the composition and structure of fish assemblages.

Changes in abiotic characteristics of water in the Paranapanema River and three lateral lagoons at mouth zone of the Jurumirim Reservoir during the flood period, São Paulo, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Zooplankton composition, dominance and abundance as indicators of environmental compartmentalization in Jurumirim Reservoir (Paranapanema River), São Paulo, Brazil

Spatial and temporal patterns in the distribution of the zooplankton in a large tropical reservoir were investigated for a year. The zooplankton was sampled at 10 limnetic stations. Rotifera were richest in number of species and individuals, especially in transitional river-lake zones. They were dominant during the summer in nine sampling stations, and decreased in spring. The main species were Polyarthra vulgaris, Keratella americana, K. cochlearis and Conochilus unicornis. Polyarthra vulgaris was widely distributed. Keratella was more abundant at upstream stations, and a dense population of C. unicornis was observed in a lateral, sheltered compartment. Among copepods, Calanoida were more abundant in spring and Cyclopoida in autumn. Longitudinal gradients in the Calanoida/Cyclopoida relation were observed, with the predominance of Cyclopoida at upstream sampling stations and Calanoida in more lacustrine zones towards the dam. Notodiaptomus iheringi, Thermocyclops minutus and T. decipiens were the main species. Diaphanosoma birgei, the most abundant cladoceran, mainly occurred in lacustrine zones, while Moina minuta was more abundant at riverine sampling stations, generally in association with Bosminopsis deitersi. Peaks of tintinnid protozoans were observed in upstream zones during summer and spring.

Phytoplankton composition, dominance and abundance as indicators of environmental compartmentalization in Jurumirim Reservoir (Paranapanema River), São Paulo, Brazil

Patterns in the spatial and temporal composition, dominance and abundance of the phytoplankton community of the Jurumirim Reservoir (Brazil) were studied during one year at ten different sampling stations. The main phytoplankton associations were characterized by diatoms and blue-green algae, in distinctive patterns of dominance. The main species were Microcystis aeruginosa Kuetz, Anabaena circinalis Rabenhorst, A. spiroides Kleb., A. solitaria Kleb., Aulacoseira cf. italica Grunow and A. granulata (Ehr.) Simon. A high growth of Aulacoseira was observed in the upstream zones of the reservoir in spring, at the beginning of the seasonal rainy period. This growth was a response to increased flow rates and input of fresh nutrients by the main feeder rivers. A high concentration of blue-green algae, especially Anabaena circinalis and A. spiroides, was observed in winter (dry season) in the lacustrine part of the reservoir, towards the dam. These algae benefitted from the longer water retention times and greater internal circulation of nutrients in the absence of a thermocline at this time of the year. Among the Cyanophyceae, there was an alternation between M. aeruginosa, more abundant in summer, and Anabaena, dominant in autumn and winter. A conspicuous growth of Anabaena occurred in a diverticle of the reservoir, sheltered from the main advective processes that predominate in the central channel. Higher phytoplankton diversity was associated with the contact zone between riverine and lacustrine systems.

Importance of lateral lagoons for the zooplankton assemblages (Cladocera and Copepoda) in a large tropical reservoir.

This study aimed to analyze the composition and the ecological attributes of the zooplankton assemblages (Cladocera and Copepoda), in four marginal lagoons and in the main channel of Rosana Reservoir (SE Brazil). Fieldwork was carried out in September and November/2004 and January, March, May and August/2005. A total of 72 taxa were identifed (55 cladocerans and 17 copepods). Seasonally, a signifcant higher richness was observed during the rainy period. The lateral lagoons, compared to the reservoir, and the rainy period, compared to the dry one, showed higher zooplankton abundance. Copepods exhibited higher abundance than cladocerans. Among the copepods, there was a higher abundance of nauppli forms in the lateral lagoons and in the dry period. Calanoida dominated in relation to Cyclopoida. The most numerous cladoceran family was Bosminidae, followed by Daphniidae. The results showed that the zooplankton assemblages are infuenced by the meteorological factors, by some important nutrients (indirectly) and by the phytoplankton abundance. This pattern indicated that in the lateral lagoon system the communities are controlled by bottom-up mechanisms. The results validate the hypotheses that lateral lagoons have a prominent ecological role for the zooplankton of Rosana Reservoir and also evidenced the main driving forces infuencing the composition and ecological attributes of the assemblages. The incorporation of the reservoir lateral lagoons in regional environmental programs should be a target strategy for the conservation of the aquatic biota, mitigating the negative impact of the dam.

Natural and artificially-induced habitat complexity and freshwater fish species composition

The effects of habitat complexity, induced by construction of artificial reefs, on the fish assemblages in the Barra Bonita reservoir, Brazil, and in the lotic zone immediately below the dam were studied. Four artificial reefs were constructed in each habitat at variable distances from the shore. Multiple correspondence analysis showed that the factors distance from the shore and type of habitat were determinants for the group formation, and artificial reefs had a lesser effect. Fish species composition was about the same at locations with and without reefs.