The terms fat and oil refer to triglycerides of several profiles of fatty acids. Fatty acids that are not bound to other organic components as glycerol are the so-called free fatty acids. Lipids constitute the main energetic source for animals and they have the highest caloric value among all the nutrients. Linoleic acid is the only fatty acid whose dietetic requirement has been demonstrated. Besides supplying energy, the addition of fat to animal diets improves the absorption of fat-soluble vitamins, decreases pulverulence, increases diet palatability, and the efficiency of utilization of the consumed energy. Furthermore, it reduces the rate of food passage through the gastrointestinal tract, which allows a better absorption of all nutrients present in the diet. The energetic value of oils and fats depend on the following: the length of the carbonic chain, the number of double bonds, the presence or absence of ester bonds (triglycerides or free fatty acids), the specific arrangements of the saturated and unsaturated fatty acids on the glycerol backbone, the composition of the free fatty acid, the composition of the diet, the quantity and the type of the triglycerides supplemented in the diet, the intestinal flora, the sex and the age of the birds. In birds, body fat composition is similar to the composition of the fat from the diet. The apparent digestibility of unsaturated fats is high in the first days of life of birds, whereas apparent digestibility of saturated fats is low. The quantity of oils or fats is assessed by the following methods: titration, moisture, impurities, unsaponifiable, saponification value, percentage of fat, percentage of free fatty acids/ acidity and the profile of fatty acids. The methods initial peroxide value, active oxygen method, osi, iodine value, and analysis of the thiobarbituric acid (TBARS) are specific to evaluate the oxidative stability. Considering diets with the same nutritive values, birds fed with rations containing oil present better performance than birds fed no oil. Moreover, the use of oil or fat in diets for broilers may change both the composition and the quality of the carcass.

The effects of different dietary lipids on the fatty acid profiles of eggs produced by 20- and 54-wk-old Dekalb laying hens were investigated. The 4 treatments were based on the lipid source added to the diet: soybean oil, sunflower oil, linseed oil, or control (no added oil). The experimental design was a simple random-sample design using a 4 × 2 factorial arrangement (4 treatments and 2 ages). The fatty acid composition of the yolks of eggs produced by the laying hens was analyzed. The fatty acid profiles found in the egg yolks were the same as those provided in each diet. Eggs laid by hens fed the diet containing soybean oil had a large amount of n-6 polyunsaturated fatty acids (PUFA), whereas eggs laid by hens fed the diet containing linseed oil had the highest percentage of n-3 PUFA. A decrease in PUFA deposition in egg yolks was observed as the laying hens got older. Eggs of hens fed the diet containing linseed oil presented an n-6:n-3 ratio of 2.01 in younger chickens and 2.17 in older ones. The trans fat percentages found in the egg yolks of all treatments were very low. It was concluded that the quantity of fatty acids present in the egg yolk may be altered according to the source of lipids in the diets; the addition of linseed oil to the ration of laying hens resulted in the production of n-3-enriched eggs and excellent n-6:n-3 ratios, and the egg yolks had insignificant amounts of trans fat, irrespective of the different lipid sources added to the diets or the age of the chickens.

Qualidade de ovos de consumo submetidos a diferentes condições de armazenamento[ RESUMOVerificou-se a qualidade interna de ovos de consumo armazenados sob diferentes condições, utilizando-se 768 ovos, provenientes de galinhas Hy-line com 40 semanas de idade. Os tratamentos foram dispostos no delineamento inteiramente casualizado em arranjo fatorial 2x4x8 (ovos embalados em filme plástico e não embalados), quatro períodos de estocagem em temperatura ambiente (zero, cinco, 10 e 15 dias) e oito períodos de armazenamento sob refrigeração (zero, cinco, 10, 15, 20, 25, 30 e 35 dias). Foram avaliados os valores das Unidades Haugh (UH) e os de pH do albúmem (pH). Os valores de UH diminuíram com a estocagem, e houve uma queda mais acentuada nos ovos que permaneceram em temperatura ambiente. A embalagem das bandejas de ovos mostrou-se eficaz na preservação da qualidade interna dos ovos, pois os valores de UH mantiveram-se altos por um maior período de estocagem. Os índices de pH aumentaram com o período de armazenamento dos ovos (P≤0,05) independentemente da temperatura de estocagem e do uso da embalagem. Foi concluído que a temperatura e o tempo de armazenamento dos ovos exercem influência nos valores de UH, e que a embalagem das bandejas de ovos em filme plástico melhora a qualidade interna dos ovos.Palavras-chave: ovo, estocagem, unidade Haugh, pH do albúmen ABSTRACTThe internal quality of 768 commercial white eggs from 40-week-old Hy-Line laying hens was evaluated after storage under different conditions. The eggs were submitted to treatments in a factorial scheme of 2x4x8, being two types of package (using plastic film or not), four periods of storage (zero, five, 10, and 15 days), and eight refrigerated storage times (zero, five, 10, 15, 20, 25, 30 and 35 days) (Brasil, 1997) determine condições mínimas internas (câmaras de ar variando de 4 a 10mm; gemas translúcidas, firmes, consistentes e sem germe desenvolvido; claras transparentes, consistentes, límpidas, sem manchas e com as chalazas intactas), na prática, somente o peso e as características da casca têm sido considerados.

Qualidade de ovos comerciais submetidos a diferentes condições de armazenamento

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

RESUMOAvaliaram-se os efeitos da idade das matrizes leves e do período de armazenamento dos ovos sobre o rendimento de incubação. Foram utilizados 7.224 ovos da linhagem Dekalb, distribuídos de acordo com delineamento experimental inteiramente casualizado, sendo a altura de bandeja uma covariável. Os tratamentos foram definidos pelas idades das matrizes (32 e 57 semanas de idade) e o período de armazenamento dos ovos (três, cinco e sete dias), totalizando seis tratamentos com 14 repetições. A idade das aves influenciou o peso do ovo. Houve aumento na perda de peso dos ovos das matrizes de 32 e 57 semanas de idade, durante o armazenamento (10,48 e 14,16%, respectivamente) e na transferência (10,40 e 12,07%, respectivamente). Verificou-se maior taxa de eclosão (86,90%) em ovos produzidos pelas matrizes novas. Independentemente da idade da matriz, à medida que aumentou o período de armazenamento, houve diminuição na taxa de eclosão dos ovos férteis (86,06 e 82,39%, para as matrizes de 32 e 57 semanas de idade, respectivamente). As matrizes com 57 semanas de idade produziram pintos mais pesados e com menor relação peso do pinto/peso do ovo. Palavras-chave: matriz leve, armazenamento, incubação, ovos incubáveis ABSTRACT The effects of ages of light breeder hens and storage period of hatchabe eggs on the incubation efficiency were evaluated. A total of 7,224Dekalb hatching eggs were assigned according to the sample random design, and the hatching tray height was considered a co-variable. The treatments were defined according to the breeder hens ages (32 and 57-week-old) and the period of storage of eggs (three, five, and seven days), with 14 replications. The age of the hen affected the weight of the eggs. There was loss of weight of the eggs of 32 and 57-week-old breeder hens during storage (10.48 and 14.16%, respectively) and transference (10.40 and 12.07%, respectively)

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

The objective of this study was to ascertain the influence of different dietary fiber sources and the usage of xylanase on diet of commercial layers and their influence on productive performance, egg quality, and digestive organ biometry. A total of 864 Lohmann ® White hens was fed diets with three different fiber sources (wheat bran, soybean hull, or coffee husk) with or without xylanase inclusion (concentration of 160,000 BXU/g) in a 3×2 factorial arrangement, with six replicates of 24 birds each, from 25 to 44 weeks of age. There were no interactions between dietary fiber and xylanase inclusion. The enzyme supplementation did not influence any parameters evaluated. There were dietary fiber effects on body weight gain, viability, egg weight, eggshell quality, yolk pigmentation, and liver and gizzard relative weights. Wheat bran, soybean hull, and coffee husk can be used in laying hen diets without detrimental effect on productive performance. The enzyme used had no effect on the performance and eggshell quality of laying hens.