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Efeito da classificação dos ovos sobre o rendimento de incubação e os pesos do pinto e do saco vitelino

RESUMOFoi realizado um estudo sobre qualidade da casca dos ovos incubáveis provenientes de matrizes pesadas com diferentes idades, por meio da avaliação da relação entre peso da casca e peso do ovo e análises de peso específico, espessura, porosidade, resistência e microscopia eletrônica. Os dois tratamentos foram definidos pela idade da matriz, sendo considerados ovos de matrizes novas  33 semanas  e de matrizes velhas  63 semanas. Os ovos de matrizes com 33 semanas foram mais leves, e o número de poros por cm 2 foi menor que o de ovos das aves mais velhas. Ovos de aves com 63 semanas apresentaram menor percentual de casca em relação ao peso do ovo, menor peso específico e menores resistência e espessura da casca. A proporção das membranas da casca em relação à sua espessura total foi maior nas matrizes mais novas. Concluiu-se que ovos de matrizes velhas têm qualidade de casca inferior aos ovos das matrizes novas e que as membranas da casca nos ovos de matrizes novas desempenham papel relevante em sua estrutura.Palavras-chave: incubação, matrizes pesadas, qualidade de casca do ovo ABSTRACT We conducted a study on eggshell quality from Cobb® broiler breeders at different ages by assessing the relationship between eggshell weight and egg weight and analysis of specific weight, thickness, porosity, strength and electron microscopy. Both treatments were defined by broiler breeder age, considering eggs from young breeders (33 weeks) and eggs from old breeders (63 weeks). It was observed that eggs from breeders at 33 weeks have lower weight and number of pores per cm

RESUMOAvaliou-se o efeito da forma física da ração sobre o desempenho e o rendimento de cortes de duas linhagens de frangos de corte, Cobb e Ross. Foram utilizados 900 frangos machos, criados em galpão experimental, com idades entre um a 45 dias. Os tratamentos foram definidos pela linhagem e forma física da ração da seguinte forma: (T1) ração farelada à vontade, (T2) ração peletizada à vontade e (T3) ração peletizada controlada. Para avaliação do desempenho, o delineamento experimental foi o inteiramente ao acaso, em arranjo fatorial 3 x 2 (três dietas e duas linhagens) e cinco repetições, sendo cada repetição composta de 30 aves. Para a avaliação do rendimento de cortes da carcaça, o delineamento foi o mesmo, com exceção do número de repetições, que foi de 30, sendo cada ave considerada como uma repetição. A ração peletizada controlada reduziu o ganho de peso em relação à peletizada à vontade em 4,7% e melhorou a viabilidade da linhagem Cobb em 10%. Independentemente da linhagem, maiores ganhos de peso foram obtidos quando as aves foram alimentadas com ração peletizada à vontade. A restrição alimentar favoreceu a conversão alimentar das aves em 2%. A linhagem não influenciou os parâmetros de rendimento de cortes e porcentagens de órgãos digestivos avaliados. A peletização favorece o desempenho de frangos de corte.Palavras-chave: frango de corte, linhagem, peletização, desempenho, rendimento de cortes ABSTRACT The effect of physical form of the rations on the performance and yield of cuts of the carcass of two lineages of broilers (Cobb and Ross) was evaluated. The treatments were defined according to the lineages and physical form of the rations and were given mash ad libitum, pelleted ad libitum, and restricted pelleted (with equal intake of the given mash ration). In the trial, 900-day-old broilers

The work described in this Research Communication concerns the production of Dulce de leche (DL), that is a traditional product from South America obtained by concentration. Maillard reaction (MR) products are mainly responsible for the formation of color and flavor in this product. Lactose-hydrolyzed products have been developed to supply consumer demand, but this hydrolysis may affect the flavor, color, taste, texture and even some nutritional aspects of the product. We studied the influence of different levels of lactose-hydrolysis, sucrose addition and initial pH on the development of MR, appraised by the determination of 5-hydroxymethylfurfural (HMF). A process simulator with multi-monitoring system was used to produce 15 DL. Box-Behnken 33 experimental design was applied for the three factors: pH, lactose-hydrolysis level and sucrose concentration. Lipids, protein, ashes, carbohydrates, water activity, dissolved solids, colorimetric analysis and HMF (free and total) are among the physicochemical attributes and MR indicators analyzed in this work. The products showed significant differences in composition but all the values were in agreement with the literature. Moreover, higher levels of lactose hydrolysis and higher pH presented a direct relation with the development of MR, observed by an increase in coloration (lower luminosity) and more formation of HMF, both free and total. The present study expands the knowledge about DL spread made of lactose-hydrolyzed milk, allowing the food industries to produce a lactose free DL with nutritional and sensory characteristics closer to the traditional product.

The objective of this study was to detect the reasons of rooster's fertility decrease at 50 weeks of age. Therefore, the reproductive system of broiler breeder roosters was laparoscopic, macroscopic and histopathology evaluated, and a comparison of the anatomical aspect with the sperm analysis and birds' age was realized. Cobb roosters (n = 59) were distributed into two groups (30 and 50 weeks). Evaluations were performed with laparoscopy, macroscopy and histopathology, and seminal quality, blood serum testosterone concentration and weight were also determined. The old roosters presented smaller testicle size, higher intensity epididymal lithiasis and lower testicle sperm production, compared to the young roosters. The use of the endoscope could easily distinguish a normal-sized testicle than an atrophic one. Four old roosters with severe testicular atrophy did not show spermatogenesis, although three still had sperm in the ejaculate. This would falsely indicate a wrong diagnosis of normal fertility before the testicular atrophy took place. In conclusion, in addition to the weight increase with age, the testicular atrophy and impairment of sperm production seemed to be the main reason to the decrease in the rooster's fertility at 50 weeks of age. Therefore, the use of the laparoscopy as a way to detect the roosters with testicular atrophy before 50 weeks of age and their removal from them flock could be useful as a diagnostic tool to prevent the birds' fertility loss.

Egg storage is a common and important practice in the poultry industry. Knowledge of the effects of storage on the egg, the embryo and incubation yield is important for planning incubation by hatcheries. Recommendations for storage environmental conditions depend mainly on the breeder age and storage time. Storage from seven days or more alters the characteristics of albumen, reduces incubation yield, increases incubation period and can damage embryonic development. When working with long storage periods, the adoption of management practices such as storing the egg with the thin tip down, egg turning during storage and prestorage incubation should be considered to reduce the negative effects on the incubation yield.Egg storage is a common and necessary practice in the poultry industry. The storage period depends on the market. If demand for broiler chicks is high, hatcheries typically store eggs for short periods. Conversely, if there is an excess of fertile eggs, they will be stored for longer periods. The storage period is determined by flock age, incubator capacity and the amount of chicks that must be delivered to the customer.As many factors determine storage period, the handling of eggs in the hatchery requires employee knowledge and training about the potential effects of storage on incubation yield. The recommendations of the scientific literature about the conditions and periods for storing eggs are not always possible to apply in practice; however, the knowledge of such recommendations offers support for incubation planning.

The production of superhydrophobic coatings inspired by the surface of plant leaves is a challenging goal. Such coatings hold a bright technological future in niche markets of the aeronautical, space, naval, building, automobile, and biomedical sectors. This work is focused on the adaxial (top) and abaxial (bottom) surfaces of the leaflet of the Ceratonia silique L. (carob), a high-commercial-value Mediterranean tree cultivated in many regions of the world. The adaxial and abaxial surfaces feature hydrophobic and superhydrophobic behaviors, respectively. Their chemical composition is very simple: monopalmitin ester and palmitic acid are protuberant in the epicuticular and intracuticular wax layers of the adaxial surface, respectively, whereas 1-octacosanol dominates in the abaxial wax layers. In both surfaces, epicuticular wax is organized along a randomly oriented and intricate network of nanometer-thick and micrometer-long plates, whose density and degree of interconnection are significantly higher in the abaxial surface. The measured tilting angles for the abaxial surface (12–70°) reveal unusual variable density and water adhesion of the nanostructured plate-based texture. Optical measurements demonstrate that light reflectance/absorbance of the glaucous abaxial surface is significantly higher/lower than that of the nonglaucous adaxial surface. In both surfaces, diffuse reflectance is dominant, and the absorbance is weakly dependent on the light incidence angle. We show that the highly dense nanostructured platelike texture of the epicuticular abaxial layer of the C. siliqua leaflet works as a sophisticated light and water management system: it reflects solar radiation diffusely to lower the surface temperature, and it has superhydrophobic character to keep the surface dry. Such attributes enable efficient gas exchange (photosynthesis and respiration), transpiration, and evaporation. To mimic for the first time the abaxial surface, a templation approach was adopted using poly­(dimethylsiloxane) (PDMS)/poly­(methylphenylsiloxane) (PMPS) positive/negative replicas and a soft polymer/siloxane negative replica produced by the sol–gel process. Because high topographical variations of the biotemplate and wax adhesion to the biohybrid film affected the replication quality, the reproduction of the wax texture via the synthesis of 1-octacosanol-grafted siloxane-based hybrid materials is proposed as a suitable route to duplicate the abaxial surface with high fidelity. The natural chemical/physical strategy adopted by the C. siliqua leaflet to face the harsh Mediterranean climate is a powerful source of bioinspiration for the development of diffuse reflecting and superhydrophobic material systems with foreseen applications as dual-functional antiglare and water-repelling coatings.