Adding value to the meat of spent laying hens manufacturing sausages with a healthy appeal

The aim of this study was to evaluate the viability of the use of spent laying hens' meat in the manufacturing of mortadella-type sausages with healthy appeal by using vegetable oil instead of animal fat. 120 Hy-line® layer hens were distributed in a completely randomized design into two treatments of six replicates with ten birds each. The treatments were birds from light Hy-line® W36 and semi-heavy Hy-line® Brown lines. Cold carcass, wing, breast and leg fillets yields were determined. Dry matter, protein, and lipid contents were determined in breast and leg fillets. The breast and legg fillets of three replicates per treatment were used to manufacture mortadella. After processing, sausages were evaluated for proximal composition, objective color, microbiological parameters, fatty acid profile and sensory acceptance. The meat of light and semi-heavy spent hens presented good yield and composition, allowing it to be used as raw material for the manufacture of processed products. Mortadellas were safe from microbiological point of view, and those made with semi-heavy hens fillets were redder and better accepted by consumers. Values for all sensory attributes were evaluated over score 5 (neither liked nor disliked). Both products presented high polyunsaturated fatty acid contents and good polyunsaturated to saturated fatty acid ratio. The excellent potential for the use of meat from spent layer hens of both varieties in the manufacturing of healthier mortadella-type sausage was demonstrated.

Desempenho e qualidade dos ovos de poedeiras comerciais alimentadas com rações contendo diferentes níveis de metionina e lisina

Foram avaliados os efeitos dos níveis de metionina e lisina sobre o desempenho e a qualidade interna e externa dos ovos de poedeiras comerciais. Foram utilizadas 256 poedeiras Hisex White com 68 semanas de idade, alojadas individualmente em delineamento inteiramente casualizado em arranjo fatorial 4 õ 4, com quatro níveis de lisina (0,482; 0,682; 0,882 e 1,082%) e metionina (0,225; 0,318; 0,411 e 0,505%), totalizando 16 dietas, cada uma com quatro repetições de quatro aves. O desempenho foi avaliado por meio das características consumos de ração, lisina, metionina, proteína bruta e de energia, peso, produção e massa de ovos e conversão alimentar. A qualidade interna dos ovos foi avaliada por meio das características peso e porcentagem de albúmen e gema e pela unidade Haugh. As aves apresentaram máxima produção de ovos quando alimentadas com rações contendo 0,444% de metionina total e 0,872% de lisina total. A classificação dos ovos por tipo e as características de qualidade interna e externa dos ovos não foram influenciadas pelos níveis de metionia e lisina da dieta.

A convenient method for lecithin purification from fresh eggs

The increasing demand for fatty acid-free lecithin required modifications in existing purification methods. In this technical note we describe a purification procedure with the following steps: a) homogenization and extraction of yolks obtained from fresh eggs with acetone, b) solubilization with ethanol and solvent elimination and c) repeated solubilization/precipitation with petroleum ether/acetone. This crude extract was chromatographed on neutral alumina, which was exhaustively washed with chloroform before elution with chloroform:methanol, allowing the sequential separation of fatty acids and lecithin. Chromatographic behavior and mass spectra of the product are presented. This fast procedure yields fatty acid-free lecithin at a competitive cost.

Comparative descriptions of eggs from three species of Rhodnius (Hemiptera: Reduviidae: Triatominae)

The authors describe and compare the morphological and ultrastructural characteristics of eggs from the three most recent described species of the genus Rhodnius Stål, 1859, which have not previously been studied. These species are Rhodnius colombiensis (Mejia, Galvão & Jurberg 1999), Rhodnius milesi (Carcavallo, Rocha, Galvão & Jurberg 2001) and Rhodnius stali (Lent, Jurberg & Galvão 1993). The results revealed that there are similarities in the exochorial architecture of optical microscopy and scanning electron microscopy; these include the predominance of hexagonal cells that are common to all Rhodnius species and variable degrees of lateral flattening, which is common not only to species of this genus, but also to the Rhodniini tribe. Differences in overall colour, the presence of a collar in R. milesi, a longitudinal bevel in R. stali and the precise length of R. colombiensis can be useful distinguishing features. As a result of this study, the key for egg identification proposed by Barata in 1981 can be updated.

Lysine and zinc chelate in diets for brown laying hens: effects on egg production and composition

It was evaluated the effects of levels of digestible lysine and chelate zinc combined in the diet for laying on the egg quality. It was used 720 birds, from 48 to 60 weeks of age, distributed in a completely randomized design in a 3 × 5 factorial scheme with three levels of zinc and five levels of lysine, applied into six replicates in the experimental units of eight birds per plot. The levels were: 137, 309 and 655 ppm zinc and 0.482, 0.527, 0.582, 0.644 and 0.732% digestible lysine. It was not observed any interaction among digestible lysine and zinc for the primary variables of fractions and egg composition. Levels of zinc reduced egg weight, suggesting the lowest efficiency in nutrient intake. At the highest dietary concentration of zinc, the addition of digestible lysine coincided with a linear increase in shell weight. However, zinc addition, regardless of lysine level in the diet, resulted in the reduction of egg weight and of the percentage of mineral matter in the yolk, limiting the efficiency of mineral deposition in this fraction of the egg. Concentration of zinc that produced the best results was 137 ppm inasmuch as higher quantities limit the use of digestible lysine, with effects harming composition and egg quality. The study indicates the following requirement for digestible lysine: 0.639% from the 48th to the 52nd week, 0.679% from the 52nd to 56th week, and 0.635% from the 56th to the 60th week. Considering the total period from 48th to the 60th week, the level 0.638% of lysine or the daily intake of 707 mg of the amino acid met the requirement for egg quality of semi-heavy layers used in this study.

Response of oriental fruit moth, Grapholita molesta (Busck) (Lepidoptera: Tortricidae), eggs to gamma radiation

As insects increase in radiotolerance as they develop and usually several developmental stages of the pest may be present in the fresh shipped commodity, it is important to know the radiation susceptibility of the stages of the target insect before the establishment of ionizing radiation quarantine treatments. This study was performed to determine the radiotolerance of eggs of the oriental fruit moth, Grapholita molesta (Busck) (Lepidoptera: Tortricidae), to gamma radiation. This species is considered as one of the most serious worldwide pests for temperate fruits, especially peaches. Eggs (12 h old) were exposed to 0 (control), 25, 35, 50, 75, 100, 125 and 150 Gy of gamma radiation. Surviving larvae were allowed to feed on an artificial diet. Three days after irradiation, it was verified that larvae`s cephalic capsules were significantly affected by gamma radiation, and the estimated mean LD(90) and LD(99) were 66.3 Gy and 125.8 Gy, respectively. Oriental fruit moth eggs revealed to be quite radiosensitive and very low doses as 50 Gy were sufficient to disrupt G. molesta embryogenesis. At 25 Gy, only male adults originated from the surviving larvae and, after mating with untreated fertile females, shown to be sterile. (C) 2010 Elsevier Ltd. All rights reserved.

Biological characteristics and thermal requirements of a Brazilian strain of the parasitoid Trichogramma pretiosum reared on eggs of Pseudoplusia includens and Anticarsia gemmatalis

A new strain of the parasitoid Trichogramma pretiosum, was collected in Rio Verde County, State of Goias, Central Brazil, and designated as T. pretiosum RV. This strain was then found to be the most effective one among several different strains of T. pretiosum tested in a parasitoid selection assay. Therefore, its biological characteristics and thermal requirements were studied, aiming at allowing its multiplication under controlled environmental conditions in the laboratory. The parasitoid was reared on eggs of Pseudoplusia includens and Anticarsia gemmatalis at different constant temperatures within an 18-32 degrees C temperature range. The number of annual generations of the parasitoid was also estimated at those temperatures. Results have shown that T. pretiosum RV developmental time, from egg to adult, was influenced by all temperatures tested within the range, varying from 6.8 to 20.3 days and 6.0 to 17.0 days on eggs of P. includens and A. gemmatalis, respectively. The emergence of T. pretiosum RV from eggs of A. gemmatalis was higher than 94% at all temperatures tested. When this variable was evaluated on eggs of P. includens, however, the figures were higher than that within the 18-30 degrees C range (more than 98%), and were also statistically higher than the emergence observed at 32 degrees C (90.2%). The sex ratio of the parasitoids emerged from eggs of A. gemmatalis decreased from 0.55 to 0.29 at 18-32 degrees C, respectively. However, for those emerged from eggs of P. includens, the sex ratio was similar (0.73, 0.72 and 0.71) at 20, 28 and 32 degrees C, respectively. The lower temperature threshold (Tb) and thermal constant (K) were 10.65 degrees C and 151.25 degree-days when the parasitoid was reared on eggs of P. includens; and 11.64 degrees C and 127.60 degree-days when reared on eggs of A. gemmatalis. The number of generations per month increased from 1.45 to 4.23 and from 1.49 to 4.79 when the parasitoid was reared on eggs of P. includens and A. gemmatalis, respectively, following the increases in the temperature. (C) 2009 Elsevier Inc. All rights reserved.

Females of the weevil Zabrotes subfasciatus manipulate the size and number of eggs according to the host seed availability

In some insects, the finding of oviposition substrate triggers the uptake into oocytes of yolk proteins that are stored in the fat body during post-embryonic development. The main host of the bean weevil Zabrotes subfasciatus (Coleoptera; Chrysomelidae; Bruchinae; Amblycerini), in which larval resources are the sole source for future egg maturation, is Phaseolus vulgaris. Despite not feeding as adults, females of this species are able to lay eggs after encountering host seeds but it is not known how females react to changes in the availability of bean seeds. In the present study, the behaviour of Z. subfasciatus facing two very different environments for oviposition is investigated, as well as how this influences offspring fitness. The results obtained show that females of Z. subfasciatus react to variations in the availability of seeds belonging to the same host species by adjusting egg size and number. Females on low bean seed density lay larger and fewer eggs than those on high bean seed density, demonstrating a trade-off between these reproductive traits. Moreover, females can adjust egg size to changing levels of host availability during the first 4 days of their oviposition period. Although no difference in offspring weight is found, those from small eggs (low competition environment) result in larger adults. No response to selection on these traits after rearing beetles on the same host for 40 generations is observed. This unresponsiveness may indicate that beetle populations behave according to their reaction norm that already allows rapid adaptation to a varying amount of host-seed availability and better exploitation of the environments of this widespread stored-seed pest.

Adding Value to the Meat of Spent Laying Hens Manufacturing Sausages with a Healthy Appeal

The aim of this study was to evaluate the viability of the use of spent laying hens` meat in the manufacturing of mortadella-type sausages with healthy appeal by using vegetable oil instead of animal fat. 120 Hy-line (R) layer hens were distributed in a completely randomized design into two treatments of six replicates with ten birds each. The treatments were birds from light Hy-line (R) W36 and semi-heavy Hy-line (R) Brown lines. Cold carcass, wing, breast and leg fillets yields were determined. Dry matter, protein, and lipid contents were determined in breast and leg fillets. The breast and legg fillets of three replicates per treatment were used to manufacture mortadella. After processing, sausages were evaluated for proximal composition, objective color, microbiological parameters, fatty acid profile and sensory acceptance. The meat of light and semi-heavy spent hens presented good yield and composition, allowing it to be used as raw material for the manufacture of processed products. Mortadellas were safe from microbiological point of view, and those made with semi-heavy hens fillets were redder and better accepted by consumers. Values for all sensory attributes were evaluated over score 5 (neither liked nor disliked). Both products presented high polyunsaturated fatty acid contents and good polyunsaturated to saturated fatty acid ratio. The excellent potential for the use of meat from spent layer hens of both varieties in the manufacturing of healthier mortadella-type sausage was demonstrated.

Increase of Cholesterol Oxidation and Decrease of PUFA as a Result of Thermal Processing and Storage in Eggs Enriched with n-3 Fatty Acids

In this work, cholesterol oxide formation and alteration of fatty acid composition were analyzed in n-3 enriched eggs under different storage periods and two temperatures. The eggs enriched with n-3 fatty acids were stored at 5 or 25 degrees C for 45 days and subsequently boiled or fried. For each treatment, 12 yolks were analyzed every 15 days including time zero. The concentrations of the cholesterol oxides 7-ketocholesterol, 7 beta-hydroxycholesterol, and 7 alpha-hydroxycholesterol increased during the storage period and were higher in fried eggs. Only the 7-ketocholesterol was affected by the storage temperature, and its concentration was highest in eggs stored at 25 degrees C. There was no significant difference in the contents of cholesterol and vitamin E at the different storage periods; however, the concentration of vitamin E decreased with thermal treatment. In addition, the n-3 polyunsaturated fatty acids, especially 18:3, 20:5, and 22:6, were reduced throughout the storage at 5 and 25 degrees C.

Antimicrobial activity in the tick Rhipicephalus (Boophilus) microplus eggs: Cellular localization and temporal expression of microplusin during oogenesis and embryogenesis

Arthropods display different mechanisms to protect themselves against infections, among which antimicrobial peptides (AMPs) play an important role, acting directly against invader pathogens. We have detected several factors with inhibitory activity against Candida albicans and Micrococcus luteus on the surface and in homogenate of eggs of the tick Rhipicephalus (Boophilus) microplus. One of the anti-M. luteus factors of the egg homogenate was isolated to homogeneity. Analysis by electrospray mass spectrometry (ESI-MS) revealed that it corresponds to microplusin, an AMP previously isolated from the cell-free hemolymph of X (B.) microplus. Reverse transcription (RT) quantitative polymerase chain reactions (qPCR) showed that the levels of microplusin mRNA gradually increase along ovary development, reaching an impressive highest value three days after the adult females have dropped from the calf and start oviposition. Interestingly, the level of microplusin mRNA is very low in recently laid eggs. An enhance of microplusin gene expression in eggs is observed only nine days after the onset of oviposition, achieving the highest level just before the larva hatching, when the level of expression decreases once again. Fluorescence microscopy analysis using an anti-microplusin serum revealed that microplusin is present among yolk granules of oocytes as well as in the connecting tube of ovaries. These results, together to our previous data. suggest that microplusin may be involved not only in protection of adult female hemocele, but also in protection of the female reproductive tract and embryos, what points this AMP as a considerable target for development of new methods to control R. (B.) microplus as well as the vector-borne pathogens. (c) 2009 Elsevier Ltd. All rights reserved.

BYC, an atypical aspartic endopeptidase from Rhipicephalus (Boophilus) microplus eggs

An aspartic endopeptidase was purified in our laboratory from Rhipicephalus (Boophilus) microplus eggs [Logullo, C., Vaz, I.S., Sorgine, M.H., Paiva-Silva, G.O., Faria, F.S., Zingali, R.B., De Lima, M.F., Abreu, L., Oliveira, E.F., Alves, E.W, Masuda, H., Gonzales, J.C., Masuda, A., and Oliveira, P.L., 1998. Isolation of an aspartic proteinase precursor from the egg of a hard tick, Rhipicephalus (Boophilus) microplus. Parasitology 116, 525-532]. Boophilus yolk cathepsin (BYC) was tested as component of a protective vaccine against the tick, inducing a significant immune response in cattle [da Silva, VI., Jr., Logullo, C., Sorgine, M., Velloso, F.F., Rosa de Lima, M.F., Gonzales, J.C., Masuda, H., Oliveira, P.L., and Masuda, A., 1998. Immunization of bovines with an aspartic proteinase precursor isolated from Rhipicephalus (Boophilus) microplus eggs. Vet. Immunol. Immunopathol. 66,331-341]. In this work, BYC was cloned and its primary sequence showed high similarity with other aspartic endopeptidases. In spite of this similarity, BYC sequence shows many important differences in relation to other aspartic peptidases, the most important being the lack of the second catalytic Asp residue, considered to be essential for the catalysis of this class of endopeptidases. When we determined BYC cleavage specificity by LC-MS, we found out that it presents a preference for hydrophobic residues in P1 and P1` in accordance to most aspartic endopeptidases. Also, when analyzed by circular dicroism, BYC presented high beta sheet content, also a characteristic of aspartic endopeptidases. On the other hand, although both native and recombinant BYC are catalytically active, they present a very low specific activity, what seems to indicate that this peptidase will digest its natural substrate, vitellin, very slowly. We speculate that such a slow Vn degradative process might constitute an important strategy to preserve egg protein content to the hatching larvae. (c) 2007 Elsevier Inc. All rights reserved.

Estabilidade oxidativa e microbiológica em carne de galinha mecanicamente separada e adicionada de antioxidantes durante período de armazenamento a -18 °C

Com o objetivo de acompanhar a estabilidade físico-química e microbiológica da carne mecanicamente separada (CMS) de diferentes origens e estocada durante 99 dias a -18 °C, foi realizada prévia mistura de conservante (nitrito de sódio) e antioxidante (eritorbato de sódio) em CMS obtida de duas linhagens de aves: galinhas matrizes de corte e galinhas poedeiras comerciais brancas. Na CMS de cada linhagem foram realizados três diferentes tratamentos: 1) controle (sem aditivos); 2) adição de 150 ppm de nitrito; e 3) adição de 150 ppm de nitrito e 500 ppm de eritorbato. Os resultados encontrados demonstraram que a adição de nitrito isoladamente não impediu a oxidação lipídica, avaliada através do índice de TBARS, nem a alteração na cor, avaliada em colorímetro. Por outro lado, a adição de nitrito juntamente com eritorbato foi efetiva na redução dos problemas de oxidação lipídica na CMS de galinhas matrizes, e em menor grau, na CMS de poedeiras. A adição de nitrito e eritorbato na CMS também melhorou a preservação da cor vermelha desejável (a*) ao longo do tempo. A avaliação da estabilidade microbiológica da CMS, realizada no primeiro e último dia de estocagem congelada, para microrganismos mesófilos, Escherichia coli, Staphylococcus aureus, Clostridium perfringens e Pseudomonas spp., e quinzenalmente para microrganismos psicrotróficos, indicou que não houve uma variação significativa nas contagens em função do tratamento utilizado (diferentes aditivos adicionados). Não foi detectada Salmonella spp. em nenhuma das amostras analisadas. Em função da melhoria da estabilidade oxidativa, recomenda-se a adição de nitrito (150 ppm) e eritorbato (500 ppm) em CMS de galinhas matrizes a ser estocada congelada por um período prolongado.

Uso de fosfatos com diferentes relações flúor: fósforo na alimentação de poedeiras semipesadas na fase de produção

Um experimento foi conduzido para verificar os efeitos de diferentes relações flúor:fósforo (F:P) na dieta sobre o desempenho e as concentrações de cálcio, fósforo, magnésio e flúor na tíbia de poedeiras comerciais semipesadas. Foram utilizadas 160 galinhas poedeiras, distribuídas em delineamento inteiramente casualizado, com quatro tratamentos (fontes de fósforo com diferentes relações flúor:fósforo - 1:40; 1:60; 1:80; 1:100) e cinco repetições de oito aves. No final do experimento, foram abatidas duas aves de cada repetição para coleta da tíbia e análise dos teores de flúor, cálcio, fósforo e magnésio. As relações flúor:fósforo não afetaram o consumo de ração, a produção de ovos, a conversão alimentar, o peso dos ovos e a gravidade específica. Entretanto, a porcentagem de casca e a espessura da casca foram menores quando a relação F:P foi de 1:100. Apesar da ausência de efeitos na produção de ovos, verificou-se redução de 7,3; 5,4 e 9,8% na produção entre as aves que receberam ração com a maior relação F:P (1:100) em comparação àquelas alimentadas com as rações com as relações de 1:40; 1:60 e 1:80, respectivamente. A deposição óssea de flúor reduziu e a de magnésio aumentou nas aves alimentadas com a ração contendo as maiores relação de F:P. As fontes de fósforo, nas relações fluor:fósforo de 1:40 a 1:80, podem ser utilizadas em dietas para poedeiras comerciais, pois não afetam o desempenho e a qualidade da casca dos ovos.

Vitaminas D e C para poedeiras na fase inicial de produção de ovos

Um experimento foi conduzido com o objetivo de avaliar os efeitos de duas fontes de vitamina D e três níveis de vitamina C sobre as características de desempenho, a qualidade interna e externa dos ovos, os níveis de cálcio total e iônico séricos e a resistência óssea de poedeiras. Foram utilizadas 288 galinhas da linhagem ISA Babcock B300® com 23 semanas de idade, durante um período experimental de 12 semanas. Utilizou-se o delineamento inteiramente ao acaso em arranjo fatorial 2 × 3, com os fatores: fontes de vitamina D (colecalciferol e 25-hidroxicolecalciferol - 25(OH)D3) e de vitamina C (0, 100 e 200 ppm), totalizando seis tratamentos com oito repetições de seis aves. O nível basal de colecalciferol foi de 2.756 UI/kg, correspondendo a 5,51 g do produto comercial Hy.D®/t de ração, como fonte de 25(OH)D3. Os fatores estudados não influenciaram o consumo de ração, a produção, o peso e a massa de ovos. Observou-se efeito da interação de fontes de vitamina sobre a conversão alimentar, que foi melhor quando utilizado metabólito 25(OH)D3 na ausência de vitamina C. Interações foram observadas para porcentagem de albúmen e porcentagem de gema, que aumentaram na presença de 200 ppm de vitamina C. O peso específico dos ovos, as concentrações de cálcio sérico, cinzas ósseas e a resistência à quebra não foram influenciadas pelas fontes de vitamina D e C. Houve interação para porcentagem e espessura de casca, cujos maiores valores foram obtidos com a suplementação de vitamina C na presença de 25(OH)D3. Em poedeiras na fase inicial de produção, a conversão alimentar é melhor com a utilização do 25(OH)D3 e a espessura e porcentagem de casca também melhoram com a utilização de 25(OH)D3 e a suplementação de vitamina C nas dietas (100 ou 200 ppm, respectivamente).