In this study we assessed the relationship between the laboratory and field performance of different isofemale lines of Trichogramma pretiosum Riley. In comparative assays, we used three rare mitochondrial haplotypes as genetic markers of the isofemale lines, and by introgressing these mitochondrial haplotypes into each of 15 genetically different nuclear lines, also tested the assumption that mitochondria are neutral markers. In a laboratory trial, 45 isofemale lines (15 nuclear genotypes x three mitochondrial haplotypes) were ranked in three categories (best, intermediate and worst) according to the mean offspring production and the proportion of female offspring. Subsequently, lines from each of the three categories were selected for field releases to quantify field parasitism on Ephestia kuehniella. Temporally separate releases were done in a transgenic Bt cornfield, with four plots, each with 50 points of recapture. The points of recapture consisted of trap cards with eggs of E. kuehniella collected daily. The trap cards were maintained in the laboratory at 25°C until the adult wasps emerged, and the maternal identity of the wasps was determined using qPCR and high-resolution melt curve analysis to determine the mitochondrial haplotype. The results showed that these measures of laboratory performance (fecundity and offspring sex ratio) were good predictors of field success in T. pretiosum. We also report strong evidence discrediting the assumption that mitochondria are neutral, in view of the correlation between performance and mitochondrial haplotype.
The promoter region and the beginning of the coding region of the hsp70 stress gene were analysed in broiler chickens of a commercial breed (Hubbard-Pettersen), a breed selected for weight gain (PP1) and a non-selected breed (naked-neck Label Rouge). The naked neck gene (Naked neck, Na), which reduces feathering in birds and is thus related to heat resistance, was present in both PP1 and Label Rouge breeds. Genomic DNA was restricted with PstI and Southern blotting analysis of the samples revealed the absence of polymorphic sites for that enzyme in the promoter region and beginning of the coding region of the hsp70 gene of studied birds. PCR-SSCP analysis of these regions, however, indicated the presence of polymorphisms in the beginning of the coding region and the sequencing of the PCR products confirmed and identified two polymorphic sites in this region: a transition A → G in position +258 and a transversion C → G in position +276. Both mutations were considered to be silent, since they did not modify the aminoacid sequence of the protein Hsp70. The promoter region of the hsp70 gene was identical in all studied birds, indicating that the regulation pattern of this gene must be the same in all birds at the promoter region. Three different alleles (hsp70-1, hsp70-2 and hsp70-3) were identified for the hsp70 gene from the observed mutations. The allele hsp70-3 was detected in only two breeds, Hubbard-Pettersen and PP1, but at a low frequency (0,016 and 0,006, respectively).
Summary A wide range of imaging and spectroscopy technologies is used in medical diagnostics, quality control in production systems, military applications, stress detection in agriculture, and in ecological studies of both terrestrial and aquatic organisms. The growing interest and use of imaging based research is mainly driven by technological improvements, reductions in equipment costs and improvements of classification methods. In this study, we hypothesize that reflectance profiling can be used to successfully classify animals that are otherwise very challenging to classify. This methodological approach is supported by extensive literature in species-specific variation in cuticular composition of hydrocarbons. We acquired hyperspectral images from adult specimens of the egg parasitoid genus, Trichogramma (T. galloi, T. pretiosum and T. atopovirilia), which are about 1.0 mm in length. We also acquired hyperspectral images from host eggs containing developing Trichogramma instars. These obligate egg endoparasitoids species are commercially available as natural enemies of lepidopteran pests in food production systems. Due to their minute size and physical resemblance, classification is both time-consuming and requires high level of technical experience. The classification of reflectance profiles was based on a combination of average reflectance and variogram parameters (describing the spatial structure of reflectance data) of reflectance values in individual spectral bands. Although variogram parameters (variogram analysis) are commonly used in large-scale spatial research (i.e. geoscience and landscape ecology), they have only recently been used in classification of high-resolution hyperspectral imaging data. The classification model of parasitized host eggs was equally successful for each of the three species and was successfully validated with independent data sets (>90% classification accuracy). The classification model of adult specimens accurately separated T. atopovirilia from the other two species, but specimens of T. galloi and T. pretiosum could not be accurately separated. Interestingly, molecular-based classification (using the DNA sequence of the internally transcribed spacer, ITS2) of Trichogramma species published elsewhere corroborate the classification, as T. galloi and T. pretiosum are closely related and comparatively distant from T. atopovirilia. Our results suggest that non-destructive acquisition of reflectance data from the external surface of animals may be of relevance to a wide range of commercial (i.e. producers of biocontrol agents), taxonomic, and evolutionary research applications.
RESUMO -Este estudo avaliou a influência de genótipos e do sistema de criação sobre o desempenho de frangos de corte tipo caipira. Foram utilizadas duas linhagens experimentais (Caipirinha e 7P) e duas comerciais (Label Rouge e Paraíso Pedrês) criadas nos sistemas intensivo e semi-intensivo (acesso a piquete com gramínea após 21 dias de idade), em um experimento no delineamento em faixas com oito tratamentos, quatro repetições e 35 aves por unidade experimental. Ração à base de milho e farelo de soja e água foram fornecidas ad libitum, na área interna apenas, e as aves do sistema semi-intensivo tiveram livre acesso à área de pastejo. Cada unidade experimental foi criada até atingir o peso médio de 2300 g. Foi detectada interação linhagem x sistema de criação na variável idade para atingir 2300 g (idade 2300) e ganho de peso médio diário, sendo que a linhagem Caipirinha criada no sistema semi-intensivo teve Idade 2300 aumentada (79,2 dias vs 73,2 dias). Não houve diferença na Label Rouge (84,0 dias vs 62,2 dias) e Paraíso Pedrês (60,8 dias vs 61,0 dias). O consumo de ração (5688 g) e a conversão alimentar (2,46) das aves Label Rouge diferiram das demais (consumo de 4304 a 4996 g e conversão de 1,87 a 2,13), e o sistema de criação não afetou essas variáveis. A mortalidade não foi afetada pelas linhagens ou sistema de criação. O acesso à pastagem no sistema semi-intensivo não representou economia de ração ou melhoria na conversão alimentar, mas resultou em redução no ganho diário de peso da linhagem Caipirinha, provavelmente em razão de sua maior permanência no piquete.Palavras-chave: desempenho, frango tipo caipira, sistema de criação Effect of Genotype and Rearing System on Performance of Alternative Lines of Broiler ChickensABSTRACT -The present study evaluated the influence of genotype and rearing system on the performance of alternative lines of broiler chickens. Two experimental lines (Caipirinha and 7P) and two commercial lines (Label Rouge and Paraíso Pedrês) were reared under intensive or semi-intensive (access to the pasture area after 21 d of age) in an experiment with eight treatments, four replicates and 35 birds per experimental unit. Corn-soybean meal based feed and water were offered ad libtum in the pen area only, and the chickens in the semi-intensive system had free access to the pasture area. The experiment was terminated when each pen reached 2300 g of average weight. Interaction line x system was detected for variable age at 2300 g (Age 2300) and average daily weight gain; the line Caipirinha on the semi-intensive had Age 2300 increased ( (5688 g) and feed conversion (2.46) for the Label Rouge broilers were different from the others (feed intake from 4304 to 2996 g and feed conversion from 1.87 to 2.17), and rearing system affect these variables. Mortality was not affected by genetic lines or rearing system. The access to pasture in the semi-intensive system did not result in feed economy or improvement in the feed conversion, but resulted in reduction on the daily weight gain (as a consequenc...
RESUMO -Realizou-se o presente trabalho com o intuito de avaliar a influência do sistema de criação (intensivo e semi-intensivo) no desempenho (peso corporal e conversão alimentar), na condição fisiológica sob estresse térmico (temperatura retal, freqüência respiratória e hematócrito) e comportamento (freqüência ao pasto) de frangos de corte. Foram utilizadas quatro linhagens de frangos de corte, duas tipo caipira e duas comerciais. Para avaliação do desempenho e condição fisiológica das aves nas idades de 45, 55, 65 e 75 dias, instalou-se um experimento no qual as aves foram alojadas em boxes constituídos de 4,5 m 2 de área interna (abrigo) e 35 m 2 de área de pastejo com lotação de 35 aves/box. Outro experimento foi instalado para avaliação da freqüência das aves ao pasto entre o 35 o e 75 o dia de idade. Uma das linhagens avaliadas não demonstrou ser adaptada ao sistema semi-intensivo de criação. Verificaram-se diferenças significativas nos parâmetros de desempenho e de condição fisiológica das aves nos dois sistemas. Na criação semi-intensiva obtiveramse menores valores para temperatura retal, taxa respiratória e hematócrito e melhores valores de peso corporal e conversão alimentar. Concluiu-se que a criação semi-intensiva proporcionou condições que aumentaram o bem-estar das aves, tendo influenciado positivamente o desempenho e a condição fisiológica das linhagens avaliadas, mesmo sob condições de estresse térmico.Palavras-chave: adaptação, bem-estar, comportamento, sistema semi-intensivo Influence of the Rearing System on Performance, Physiological Condition and Behaviour of Broilers LinesABSTRACT -The objectives of this research were to evaluate the influence of rearing systems (intensive or semi-intensive) on the performance (body weight and feed efficiency), chicken physiological condition under heat stress (rectal temperature, respiratory frequency and hematocrit) and behavioural parameters (frequency in the pasture areas) of broilers lines. To evaluate broiler's performance and physiological condition on the ages of 45, 55, 65 and 75 days one experiment was carried out in boxes with 4,5 m 2 of inside area and 35 m 2 of outside area were 35 broilers were reared in each box. Another experiment was carried out to evaluate the frequency of broilers it the pasture areas from 35 to 75 days of age. One of the evaluated lines did not show adaptation to the semi-intensive rearing system. Significant differences were found in broilers performance and physiological conditions in both systems. In the semi-intensive rearing system the rectal temperature, respiratory frequency, hematocrit and feed efficiency were smaller and body weight larger than in the intensive rearing system. It was concluded that the semi-intensive rearing system provided conditions that increased broilers welfare and positively influenced the physiological conditions and performance of the broilers.
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