Effects of amylin on egg quality traits of hens during the early laying period

This study was conducted to investigate the effects of amylin, a pancreatic hormone polypeptide, on egg quality traits in laying hens. A total of 40 birds (14 wk of age) were randomly divided into two treatments with two replicates, 10 birds in each replicate. Twenty birds were subcutaneously injected with amylin at 75 µg/kg every other day (treatment 1), and the remaining animals (20 hens) were given only water as the control group (treatment 2). Eggs collected from the two groups (140 eggs per group) were examined for several quality performance traits such as egg weight, specific gravity, shape index, eggshell strength, eggshell thickness, eggshell ash, eggshell weight, Haugh unit (HU), albumen index, yolk index, yolk color, and albumen height. The results indicated that amylin had a positive effect on some egg quality traits in laying hens. Specific gravity, eggshell thickness, eggshell weight, HU, albumen index, yolk index, and albumen height, which are all considered as important quality parameters from the consumer point of view, especially HU, were relatively improved in the amylin treatment group. These results showed that the injection of 75 µg/kg amylin has a significant effect on some egg quality traits. Considering that egg quality characteristics are crucial for the egg industry, this study can be a reference for the detailed investigation of the use of amylin in the different stages of egg production.

Assessing Differences in the Quality Properties and Ultrastructure of Eggshell as Affected by Chicken Strain and Flock Age During Incubation Period

Three hundred hatching eggs from two layer breeder flocks (Hy-Line Brown and hy-Line W-36; 150 each) were obtained at three different periods of laying cycle (early, middle and late stages). The hatching eggs were randomly taken to assess the impact of chicken strain, age, and hatching time on some eggshell measurements and structures. Results indicate that egg weight, shell percentage and shell thickness were significantly affected by strain, breeder age, and incubation time. Increasing rate of calcium absorption and utilization by the embryos during the embryonic stage clearly reflects the decrease occurred in eggshell strength. The differences of eggshell breaking strength during incubation time periods were 0.41 and 0.55 kg/cm2, the differences due to the incubation time may be due to the higher demand for calcium utilization in the late incubation period (18 days), observed on the10th day of incubation. Brown eggs recorded significant higher calcium percentage in eggshell compared to the white ones. The brown breeder hens recorded significant higher total pores per egg compared to the white egg. Concerning eggshell ultrastructure, total thickness of the brown eggshell was significantly higher than those of the white eggshell by about 3.7%. All parameters, except for total thickness, were significantly affected by the interaction between strain and breeder age. Finally, we conclude that some traits including egg weight, shell percentage, shell thickness, calcium percentages in eggshell, and total pores per egg were significantly affected by strain, breeder age, and incubation time. Eggshell ultrastructure of brown egg was better compared to the white ones.(AU)

Effect of Cold Chain on Chicken Egg Quality in a Simulated Post Washing Processing and Consumer Storage Model

This study assessed the effect of the cold chain on egg quality in a model simulation of post-washing processing and consumer storage. Post-washed eggs were assigned to 12 groups that simulated the conditions of temporary storage after washing (step 1; 7°C or 25°C for 1 day), transportation (step 2; 7°C or 30°C for 8 h), and selling or storage (step 3; 7°C, 25°C or 30°C for 4 weeks). The freshness and microbial characteristics of the eggs were analyzed for 4 weeks. High-temperature conditions in steps 1 or 2 resulted in reduced quality and more bacteria on eggshells, and this egg quality deterioration worsened after storage for over 2 weeks. In step 3, the quality of the eggs stored at 7°C was maintained during the entire storage, whereas the eggs stored at 25°C had lower quality and broken vitelline membranes in week 4, and the eggs stored at 30°C were spoiled. Eggs should be stored from post-washing until storage by consumers in a cold environment without interruption of temperature control to maintain quality and safety. Consumers must be aware that eggs should be stored at refrigerator temperature.(AU)

Carotenoids and retinoids in the gonad of broodstock pikeperch: accumulation during vitellogenesis and influence on egg quality in farmed pikeperch Sander lucioperca

Carotenoids are determinants of reproductive fitness and egg quality. Here we studied the accumulation of astaxanthin (AX), canthaxanthin (CA) zeaxanthin (ZX), lutein (LU), retinol (RX) and dehydroretinol (DR) during vitellogenesis comparing previtellogenic and vitellogenic pikeperch (Sander lucioperca) eggs (n = 5 each), as well as selected tissues (liver, fat and muscles) in first süawning females (1176-1450 g). Futhermore, we compared egg batches with high (88­99% hatching rate, n = 5) or low (40­67% hatching rate, n= 5) egg quality. Vitellogenic follicles revealed higher concentrations of DR, RX, ZX and LU compared to previtellogenic follicles. Neither CA nor AX was detectable. In parallel, DR and RX were mobilized in the liver. In adipose and muscle tissue, comparing previtellogenic and vitellogenic females, no significant differences in carotenoid/retinoid content were observed. In high quality egg batches, both DR and RX were increased. LU was lower in high quality than in low quality eggs. In a conclusion, the amount of retinoids seems suboptimal in low quality egg batches and increased DR and RX are desirable in pikeperch. Since hypervitaminosis of retinoids can be problematic though, supplementation of the food with carotenoids, which can serve as precursors for retinoids, has to be carried out carefully.(AU)

Vegetable lipid sources in the diet of japanese quails in the rearing phase and effects on the initial phase of production / Fontes lipídicas vegetais na alimentação de codornas japonesas em fase de recria e sua repercussão na fase inicial de produção

This study aims to evaluate the residual effect of different lipid sources in the diet of Japanese quails (Coturnix japonica) in the rearing phase on the performance and egg quality in the initial phase of egg-laying. In the first stage, 400 Japanese quails aged 21 days were used, being distributed in a completely randomized experimental design, with five treatments and ten replicates of eight birds/replicate Treatments consisted of basal ration (BR) with 2.5% soybean oil; BR with 2.5% corn oil; BR with 2.5% cottonseed oil; BR with 2.5% sunflower oil; and BR with 2.5% canola oil.At 42 days, maintaining the initial design, all quails received a basal ration with soybean oil, in order to evaluate the residual effect of the previous phase on the performance and egg quality in the initial phase of egg-laying (43 - 84 days). The different lipid sources did not affect the performance of quails in the initial phase of production. For egg quality, yolk height, yolk diameter, yolk index, gravity, and Haugh unit (HU) showed better results in the treatment using sunflower oil. There was a residual effect of the use of lipid sources of vegetable origin in the rearing phase diet of Japanese quails on egg quality traits. Lipid sources from soybean, corn, cottonseed, canola, and sunflower seeds can be used as energy sources in the rearing diet of egg-laying quails for not being harmful to their initial performance. The longevity in egg production of quails fed with different lipid sources in the rearing phase was similar.

A pesquisa foi conduzida com objetivo de avaliar o efeito residual de diferentes fontes lipídicas na dieta de codornas japonesas (Coturnix japonica) na fase de recria sob o desempenho e a qualidade de ovos na fase inicial de postura. Na primeira etapa foram utilizadas 400 codornas japonesas com idade de 21 dias, as aves foram distribuídas em tratamentos seguindo um delineamento inteiramente casualizado com dez repetições, de oito aves, em cinco tratamentos: ração basal (RB) com 2,5% de óleo de soja, RB com 2,5 % de óleo de milho, RB com 2,5% de óleo algodão, RB com 2,5% de óleo de girassol e RB com 2,5% de óleo de canola. Aos 42 dias mantendo o delineamento inicial, todas aves receberam ração basal com óleo de soja, para que fosse avaliado o efeito residual da fase anterior sobre o desempenho e a qualidade dos ovos na fase inicial de postura (43 - 84 dias). As diferentes fontes lipídicas não afetaram o desempenho das aves na fase inicial de produção. Para a qualidade dos ovos, os parâmetros de altura, diâmetro e índice de gema, gravidade e UH foram melhores no tratamento com utilização de óleo de girassol. Houve efeito residual da utilização de fontes lipídicas de origem vegetal na dieta em fase de recria de codornas japonesas sobre as características da qualidade dos ovos. As fontes lipídicas oriundas das sementes de soja, milho, algodão, canola e girassol podem ser utilizadas como ingredientes energéticos na dieta de recria de codornas poedeiras por não serem prejudiciais ao desempenho inicial das aves. A longevidade na produção dos ovos das aves alimentadas com diferentes fontes lipídicas na fase de recria foi semelhante.

Effects of Saccharomyces Cerevisiae Supplemented Diet on Production Performance, Egg Quality and Humoral Immunity in Black Australorp and Fayoumi Layers

The present study intended to identify the effects of the Saccharomyces cerevisiae yeast on production performance and parameters related to the quality of layers' eggs. Effects of yeast on immune titers after routine vaccinations against Newcastle disease and infectious bronchitis were also studied. Fayoumi chicken (n=288) were divided in four groups (72 in each), and Black Australorp (n=288) in four groups (72 in each). Both had 12 weeks of age and were kept in 08 groups (3 replicates per treatment). Hens were fed a controlled diet along with the addition of 0.5g, 1.0 g, and 1.5 g of S. cerevisiae per kg of feed, till 25 weeks of age. Feed intake and egg production were measured on a daily basis, while body weight gain and egg weight were measured weekly. Egg quality parameters were evaluated by picking 5 eggs from every group weekly. Birds were vaccinated for Newcastle disease (ND) and infectious bronchitis (IB) at the 18th week. Subsequently, 10 days after vaccination, antibody titers were determined by Hemagglutination Inhibition and Enzyme Linked Immunosorbent Assay for both diseases. Results showed no significant effect of S. cerevisiae on layers' weight gain and feed intake. However, egg production was increased in the experimental group. Moreover, yeast supplementation impacted positively on birds' immune system. In conclusion, probiotic supplementation improved birds' egg production and immunity.(AU)

Requirement of digestible methionine + cystine in Japanese quails during the laying phase / Exigência de metionina + cistina digestível para codornas japonesas em fase de postura

An experiment was carried out with Japanese quails in the initial laying phase, from 43 to 168 days of age, to determine the nutritional requirement of digestible methionine + cystine for this period. 375 quails were used, being fifteen quails used per experimental unit. A total of 5 treatments (0.60, 0.75, 0.90, 1.05 and 1.20% digestible methionine + cystine) were used in a completely randomized design with 5 replicates each. The performance parameters evaluated were feed intake (g / bird), body weight (g), egg weight (g), laying rate (%), egg mass (g eggs.bird.day-1 ), feed conversion by mass and dozen eggs (g.g-1 of eggs, g.dz-1 of eggs), viability (%) and the body chemical composition (%). The egg quality parameters were: % of component (yolk, albumen and shell relative to egg weight), specific gravity (g mL-1 ), Haugh unit, yolk index, shell weight per surface area and thickness of the shell (mm). Quadratic effect was found on the performance parameters evaluated (P0.05). The nutritional recommendation of digestible methionine + cystine for Japanese quails at laying phase is 0.90% from the maximum point obtained for the egg mass, egg weight and laying rate, corresponding to daily intake of 241.54 mg of digestible methionine + cystine / day, respectively.

Foi desenvolvido um experimento com codornas japonesas na fase inicial de postura, de 43 a 168 dias de idade, com o objetivo de determinar a exigência nutricional de metionina + cistina digestível para este período. Foram utilizadas 375 codornas, sendo 15 aves por unidade experimental. O delineamento experimental foi inteiramente casualizado (DIC) totalizando 5 tratamentos (0,60; 0,75; 0,90; 1,05 e 1,20 % de metionina + cistina digestível) com 5 repetições cada. As variáveis de desempenho avaliadas foram, consumo de ração (g/ave), peso corporal (g), peso do ovo (g), taxa de postura (%), produção de massa de ovos (g ovos.ave. dia-1), conversão alimentar por massa e dúzia de ovos (g.g-1 de ovos, g.dz-1 de ovos), viabilidade (%) e a composição química corporal (%). As variáveis de qualidade dos ovos foram, percentagem do componente (gema, albúmen e casca em relação ao peso do ovo), gravidade específica (g mL.-1), unidade Haugh, índice de gema e peso da casca por superfície de área. Foi encontrado efeito quadrático sobre as variáveis de desempenho avaliadas (P0,05). A recomendação nutricional de metionina + cistina digestível para codornas japonesas na fase de postura é de 0,90% a partir do ponto de máxima obtido para as variáveis massa de ovos, peso de ovos e taxa de postura, correspondendo ao consumo diário de 241,54 mg de metionina + cistina digestível / dia, respectivamente.

Investigation of Egg Weight, Ovarian Follicles Morphology and Growth Differentiation Factor 9 mRNA Expression in Potchefstroom Koekoek Chicken Breed

The growth differentiation factor 9 (GDF9) gene plays a vital role in the growth and maturation of ovarian follicles in laying hens. However, its messenger ribonucleic acid (mRNA) expression levels in preovulatory ovarian follicles of indigenous chickens remain poorly understood. The study aimed to identify the association between egg weight and egg quality traits, ovarian follicles morphology, and mRNA expression levels of the GDF9 gene in pre-ovulatory ovarian follicles of the South African Potchefstroom Koekoek chicken breed. The correlation results showed that egg weight (EW) had a positively high significant correlation (p<0.01) with egg width (EWD), yolk weight (YW), shell surface area (SSA), albumen weight (AW), albumen ratio (AR) and egg volume (EV), and a positive significant correlation (p<0.05) with egg length (EL). The Student's T-test results revealed that the numbers of large yellow follicles were significantly lower (p<0.05) than those of small yellow follicles. ANOVA findings showed that there was a significant difference (p<0.05) in the average weight of the large yellow follicles. The quantitative Reverse Transcription Polymerase Chain Reaction (RT-qPCR) findings indicated that there were significant differences (p<0.05) in the mRNA expression levels of the GDF9 gene in preovulatory ovarian follicles of the Potchefstroom Koekoek chicken breed. The mRNA expression was more abundant in F1 and F4 than in other ovarian follicles.(AU)

Performance, physical egg quality, and economic index of laying hens under different rearing systems / Desempenho, qualidade do ovo e índice econômico de poedeiras em diferentes sistemas de criação

The objective was to evaluate the performance, physical egg quality (weight and gravity), and economic index of laying hens reared in cage and cage-free systems. A total of 312 40-week-old Hy-line brown laying hens were distributed in a fully randomized design, split into two treatments (cage-free and cage) with 12 replicates in each system. We housed 144 birds in galvanized-wire cages (12 birds each) and 168 birds in a cage-free system in boxes with wood shaving bedding (14 birds each). The experiment lasted 112 days and divided into four 28-day periods. Regarding performance, feed intake (g) and feed conversion (g/g) of birds reared in the cage-free system were higher (p<0.0001) than the cage system, but no differences were observed (p>0.05) for the other performance parameters and also for egg quality. As for economic index, egg production in the cage-free system was higher (p<0.0001) than the cage system. In conclusion, birds reared in the cage-free system have higher feed consumption but worse feed conversion, increasing egg production cost compared to caged birds; however, there are no changes in egg production and physical quality.(AU)

Objetivou-se avaliar o desempenho, qualidade de ovos e índice econômico de poedeiras semipesadas criadas em sistemas cage-free e em gaiolas. Foram utilizadas 312 poedeiras da linhagem Hy Line Brown, com 40 semanas de idade, distribuídas em um delineamento inteiramente casualisado (DIC), em dois tratamentos (cage-free e gaiolas) com 12 repetições em cada sistema, sendo 144 aves alojadas em gaiolas de arame galvanizado com 12 aves em cada gaiola e 168 aves alojadas em sistema cage-free, em boxes sobre cama de maravalha com 14 aves em cada repetição. O experimento teve duração de 112 dias, divididos em quatro períodos de 28 dias. Nos parâmetros de desempenho, o consumo de ração (g/aves/dia) e a conversão alimentar (g/g) foi maior (P<0,0001) nas aves criadas no sistema cage-free comparado ao sistema de gaiolas, não sendo observado diferença (P>0,05) nos demais parâmetros de desempenho e também na qualidade de ovos. No índice econômico, a produção de ovos em sistema cage-free apresentou maior valor (P<0,0001) em relação ao sistema de gaiola. Conclui-se que as aves criadas em sistema cage-free apresentam maior consumo de ração, pior conversão alimentar ocasionando um maior custo nos ovos em relação às aves criadas em gaiolas, no entanto não há alteração na produção e qualidade dos ovos.(AU)

Qualidade de ovos comerciais oriundos de poedeiras tratadas com doxiciclina / Quality of commercial egg from laying hens treated with doxycycline / Calidad de huevos comerciales de gallinas ponedoras tratadas con doxiciclina

Doxiciclinaé um fármaco do grupo das tetraciclinas indicado para tratamento de diferentes doenças, em principal a coriza infecciosa. Entretanto, antimicrobianos do grupo das tetraciclinas tem capacidade de se ligarem e indisponibilizar minerais importantes para a formação dos ovos. O objetivo do projeto foi de avaliar a interferência da doxiciclina na qualidade de ovos comerciais. Realizou-se um estudo com 100 poedeiras Dekalb Brown®onde se avaliou a cor da gema, unidade Haugh, cor da casca, peso e espessura da casca. O delineamento adotado foi o inteiramente casualizadosem um esquema fatorial 2x2, resultando nos tratamentos: sem doxiciclina ao 5° dia; com doxiciclina ao 5° dia; sem doxiciclina ao 10° dia; com doxiciclina ao 10° dia. Coletou-se 4 ovos por repetição,totalizando 48 ovos analisado por tratamento em cada um dos períodos analisados. Não foram encontradas diferenças significativas entre os tratamentos para as variáveis de qualidade interna dos ovos (cor da gema e unidade Haugh). Para as variáveis de qualidade de casca, houve uma redução significativa dos níveis de amarelo com o uso de doxiciclina por 10 dias, além da redução do peso da casca e da espessura apical e equatorial da casca, principalmente no 10º dia e com o uso de doxiciclina. Conclui-se que o uso da doxiciclina não interfere na qualidade interna dos ovos, porém confere tonalidade acinzentada as cascas, e redução de peso e espessura das mesmas.(AU)

Doxycycline is a drug from the tetracycline group indicated for the treatment of different diseases, mainly infectious coryza. However, antimicrobials from the tetracycline group can bind and make minerals important for egg formation unavailable. The aim of this project is evaluated interference of doxycycline in quality of commercial egg. A study had carried out with 100 Dekalb Brown®laying hens where evaluated the yolk color, Haugh unit,color eggshell, weight and thickness eggshell. The delimitation had completely randomized in a 2x2 factorial scheme, resulting in treatments: without doxycycline at day 5; with doxycycline a day 5; without doxycycline at day 10; with doxycycline at day 10. Four eggs had gathered per replicate, totaling 48 eggs analyzed per treatment in each of the analyzed periods. No significant differences were found between treatments for internal egg quality variables (yolk color and Haugh unit). For the shell quality variables, there was a significant reduction in yellow levels with the use of doxycycline for 10 days, in addition to a reduction in shell weight and apical and equatorial shell thickness, mainly on the 10th day and with the use of doxycycline. It is concluded that the use of the doxycycline does not interfere in the internal quality of the eggs, but it gives a greyish tonality to the eggshells, and reduces their weight and thickness.(AU)

La doxiciclina es un fármaco del grupo de las tetraciclinas indicado para el tratamiento de diferentes enfermedades, principalmente el coriza infeccioso. Sin embargo, los antimicrobianos del grupo de las tetraciclinas tienen la capacidad de unirse y hacer que minerales importantes para la formación de huevos no estén disponibles. El objetivo de este proyecto es evaluar la interferencia de la doxiciclina en la calidad del huevo comercial. Se realizó un estudio con 100 gallinas ponedoras Dekalb Brown®donde se evaluó el color de la yema, unidad Haugh, color del cascarón, peso y grosor del cascarón. La delimitación tuvo completamente al azar en un esquema factorial 2x2,resultando tratamientos: sin doxiciclina en el día 5; con doxiciclina al día 5; sin doxiciclina el día 10; con doxiciclina el día 10. Se habían recolectado cuatro huevos por réplica, totalizando 48 huevos analizados por tratamiento en cada uno de los períodos analizados. No se encontraron diferencias significativas entre tratamientos para las variables de calidad interna del huevo (color de la yema y unidad Haugh). Para las variables de calidad de la cáscara, hubo una reducción significativa de los nivelesde amarillo con el uso de doxiciclina durante 10 días, además de una reducción del peso de la cáscara y del espesor apical y ecuatorial de la cáscara, principalmente al décimo día y con el uso de doxiciclina. Se concluye que el uso de la doxiciclina no interfiere en la calidad interna de los huevos, pero da una tonalidad grisácea a las cáscaras, y reduce su peso y grosor.(AU)

Analysis of the Quality of Eggs Marketed in Santarém, Brazil

Eggs are foods with almost perfect proteins, while also containing nutrients with high biological value. The purpose of this study was to evaluate the morphological structure, physical-chemical, nutritional, and microbiological parameters of commercial and free-range eggs sold in the municipality of Santarém, State of Pará, Brazil. The two types of eggs were also compared to check for any differences in quality. The evaluations were conducted on variables such as Haugh unit, weight loss, egg width and length, specific gravity, yolk and albumen dimensions, pH, among others. A total of 240 eggs were purchased in the Brazilian municipality of Santarém (2º45'06" S and 54º70'09" W). A statistical study was also performed using the BIOESTAT 5.0 statistical program. A comparison of the industrial and free-range eggs and their various parameters is given in the tables along with the coefficient of variation. The results obtained were satisfactory and showed that the quality of eggs is affected more by environmental factors than by the source from which they are obtained. The results were also compared to previously published literature, and it was determined that this study offers a better foundation for the nutritional examination of egg quality.(AU)

Diferentes densidades de alojamento de galinhas poedeiras em gaiolas e suas respectivas produção, qualidade de ovos e escore de penas / Different housing densities of laying hens in cages and their production, egg quality andfeather score

As poedeiras criadas em sistema degaiolas tem seu bem-estar afetado devido ao menor espaço disponível para elas, o que vai de encontro da crescente pressão por grande parte de consumidores preocupados com as condições em que essas aves são criadas. A consequência dessa menor densidade de alojamento sobre a produtividade, e a qualidade de vida da ave e dos ovos por elas produzidos deve ser avaliada. O objetivo desse estudo é avaliar a produção, qualidade de ovos, e bem-estar de galinhas poedeiras criadas em diferentes densidades de alojamentos em gaiolas. Às 28 semanas de idade, foram distribuídas, em delineamento inteiramente casualizado, 120 poedeiras leves da linhagem Novogen White, após debicagem, em 24 gaiolas com dimensões de 45 cm x 50cm, em três diferentes densidades de alojamento: 562,5 cm² /ave (quatro aves/gaiola), 450 cm² /ave (cinco aves/gaiola) e 375 cm² /ave(seis aves/gaiola), com 8 repetições cada. As dietas experimentais foram isoproteicas e isoenergéticas, formuladas à base de milho e farelo de soja. O período experimental será compreendido por seis ciclos de 28 dias cada. As variáveis analisadas foram: peso do ovo, índice de gema, unidade Haugh, pigmentação da gema, porcentagem dos componentes dos ovos e espessura de casca (em milímetros). Quando as aves atingiram 44 semanas de idade, foi realizada a medição do escore de penas. Foram avaliadas 40 galinhaspor tratamento, em quatro regiões: peito, dorso, asas e posterior. Essa análise consiste emcategorizar as aves de acordo com três diferentes escores, de acordo com o tamanho da área de ausência de penas em cada região. Espera-se que a redução da densidade de alojamento das galinhas nas gaiolas propicie maior produção com melhor qualidade dos ovos, promovendo também melhor bem-estar das aves.(AU)

The well-beingof laying hens raised in cages is affected due to the smaller space available for them,which is in line with the growing pressure from a large number of consumers concerned about the conditions in which these birds are raised.The consequence of thislower housing density on productivity and the quality of life of the bird andthe eggs produced by them must be evaluated. The aim of this study is to evaluate the production, egg quality, and welfare of laying hens reared in different housing densities in cages. At 28 weeks of age, 120 light Novogen White laying hens were distributed, after beak trimming, in24 cages measuring 45 cm x 50 cm, in three different housing densities: 562.5 cm²/bird (four birds/cage), 450 cm²/bird (five birds/cage) and 375 cm²/bird (six birds/cage), with 8 repetitions each. The experimental diets were isoproteic and isoenergetic, based on corn and soybean meal. The trial period will comprise six cycles of 28 days each. The variables analyzed were: egg weight, yolk index, Haugh unit, yolk pigmentation, percentage of egg components and shell thickness (in millimeters). When the birds reached 44 weeks of age, the feather score was measured. Forty chickens per treatment were evaluated in four regions: chest, back, wings and hindquarters. This analysis consists of categorizing the birds according to three different scores, according to thesize of the area without feathers in each region. It is expected that the reduction in the hen housing density in the cages will lead to higher production with better egg quality, also promoting better hen welfare.(AU)

Requirement of digestible methionine + cystine for growing Japanese quail and its subsequent effects on laying phase

The objective of this study was to estimate the nutritional requirement of digestible methionine + cystine for Japanese quail during the growth phase and its residual effect on the laying phase. One experiment was conducted, including three phases: starter, from 1 to 14 days of age; grower, from 15 to 42 days of age; and laying, from 43 to 168 days of age. The experimental design was entirely randomized with five treatments (0.52, 0.64, 0.76, 0.88, and 1.00% of digestible methionine + cystine) and five replicates. In starter phase, 48 quail/experimental unit (box) were used; in grower phase, 31 quail/experimental unit (box) were used, which were reared until 14 days old, receiving conventional feed and, in laying phase, 12 quail/experimental unit were selected from grower phase to evaluate the residual effect. To evaluate animal performance, feed intake (g/bird), body weight (g), weight gain (g), feed conversion (g/g), and viability (%) were analyzed. At 14 and 42 days of age, the relative weight (%) of liver, spleen, and cloacal pouch organs, the birds' warping (%) and body chemical composition (%) were evaluated. During laying, performance and egg quality were evaluated. In the starter and grower stages, quadratic effects were observed for all performance variables. Laying performance results confirmed the estimates obtained in the grower phase; however, there was no effect on egg quality. Considering the best feed conversion, the nutritional recommendation of digestible methionine + cystine for Japanese quail in the starter phase is 0.85% and in the grower phase, it is 0.77%, corresponding to daily intake of 50.43 and 158.5 mg of digestible methionine + cystine/day, respectively.

Post-thaw quality of ram sperm frozen with different concentrations of low-density lipoproteins associated with non-enzymatic antioxidants

The cryopreservation reduces ram sperm quality, decreasing the pregnancy rate of ewes inseminated with thawed sperm. Hence, we aimed to improve the post-thaw quality of ram sperm replacing egg yolk on Tris-Glucose extender with different concentrations of LDL (2 or 8%), associated with the addition of 10 mM non-enzymatic antioxidants (ascorbic acid, hydroxytoluene butylate, ascorbyl palmitate, and trehalose). Semen samples were collected from six rams, split into different treatments, and frozen. After thawing, kinematic (CASA), structural (propidium iodide and carboxyfluorescein diacetate) and functional (hypoosmotic test) sperm membrane integrity was assessed. Total motility, VCL, and LIN were also assessed in thawed samples during 3 h of incubation (38 °C). The results showed that hydroxytoluene butylate at 10 mM in Tris-Glucose extender with 8% LDL improved velocity parameters immediately post-thaw compared with Tris-Glucose egg yolk extender, as well as prevented the reduction of total motility and VCL after incubation. There was no benefit of adding ascorbic acid and trehalose. Moreover, for the first time, it was shown the motility impairment promoted by ascorbyl palmitate to ram sperm.(AU)

Effects of dietary fiber on performance and egg quality of laying hens at pre-laying and laying peak

This study aimed to evaluate the effects of different levels of dietary fiber on the performance and egg quality of laying hens at pre-laying and laying peak periods. The experimental period was divided into three periods: pre-laying (16 to 19 weeks of age), the start of laying (20 to 22 weeks of age) and laying peak (23 to 28 weeks of age). The experimental design was completely randomized with treatments constituted by five levels of fiber (2.00, 2.50, 3.00, 3.50, and 4.00%) in the diets, with five replicates (pens) of six birds each, totalling 180 hens. Performance and egg quality results were evaluated by polynomial regression at 5%. Fiber levels were not influenced (p >0.05) the first laying of the hens. However, levels above 2.50% of fiber provided worst (p <0.05) performance results, regardless of the period evaluated. Shortly after the start of laying, higher levels of fiber also caused a linear reduction (p <0.05) on egg weight and percentages of yolk and albumen, and an increase (p <0.05) on eggshells. Higher fiber levels caused a linear reduction (p <0.05) in the quality of the eggs, regardless of the period evaluated. It was concluded that the fiber levels did not influence the start period of the laying. Both pre-laying and start of the laying, levels above 2.5% of fiber caused a gradual worsening in performance. From the start of laying up to laying peak, levels above 2.5% of fiber also caused a gradual worsening in egg quality.(AU)

Insect meal in poultry feed: a potential protein source

The present study aims to conduct a review on the potential use of insect meal as an alternative protein source in poultry feed, particularly to serve the rearing of free-range chickens. Insects are already part of the diet of birds in their natural habitat, and the availability of low-cost alternative foods with low environmental impact is essential for the development of the activity. The review comprehended studies that used meals consisting of silkworm (Bombyx mori) chrysalis, earthworm (Eisenia foetida), housefly (Musca domestica), black soldier fly (Hermetia illucens) and mealworm beetle (Tenebrio molitor) to replace plant-based protein sources. In general, insect meals have a high content of crude protein and ether extract, as well as an essential amino acid profile suitable for poultry feeding. The addition of insect meal in poultry feed normally shows good results as to growth performance and egg production, without causing a negative effect on carcass characteristics, meat sensory quality and egg quality, presenting itself as an alternative protein source with good prospects for replacing plant-based sources in poultry feed.(AU)

Influence of thawing temperature on sperm motility, structure, and metabolism of frozen bovine semen / Influência da temperatura de descongelamento na motilidade, estrutura e metabolismo do sêmen bovino congelado

The heating rate used during semen thawing plays an important role in reducing structural and functional damage to spermatozoa. In this study, we evaluated the influence of thawing temperature on semen quality, reactive oxygen species (ROS) production, and mitochondrial activity of cryopreserved bovine semen. A total of 195 straws of 0.5 mL from five Holstein Friesian bulls were used (39 straws per bull). Samples underwent 8 to 22 years of storage; they were processed under a standard protocol with tris-egg yolk and stored in liquid nitrogen. Samples were thawed for 30 seconds in a water bath at T1: 36 °C, T2: 38 °C or T3: 40 °C. Sperm motility and kinematics, morphology, structural membrane integrity (SMI), functional membrane integrity (FMI), acrosome integrity (AI), ROS, and mitochondrial membrane potential (ΔΨM) of post-thawing bovine sperm were evaluated. Generalized linear models were fitted to the data. Each model included the effects of bull, storage time, and treatment. The Shapiro-Wilk test was used to assess data normality, and means were compared using the Tukey test. T2 and T3 showed better results for sperm motility and kinematic parameters, SMI (%) (T1 41.9 ± 2.3; T2 45.7 ± 1.9; T3 47.4 ± 2.8), ROS (RFU/min) (T1 0.026 ± 0.007; T2 0.032 ± 0.001; T3 0.031 ± 0.001) and high-ΔΨM (RFU x 103) (67.1± 0,4; 71.3 ± 0.4; 74.2 ± 0.4) (P < 0.05). However, T1 had higher FMI (39.3 ± 2.3) than T2 (34.0 ± 1.9) (P < 0.05), though not significantly (P > 0.05) different from T3 (38.4 ± 2.2). Thawing temperatures of 38 °C and 40 °C increases motility, kinetics, membrane integrity, mitochondrial activity and ROS of cryopreserved bovine semen, compared with more conventional thawing at 36 °C.

A taxa de aquecimento usada durante o descongelamento do sêmen desempenha um papel importante na redução dos danos estruturais e funcionais nos espermatozóides. O objetivo desta pesquisa foi avaliar a influência da temperatura de descongelamento na qualidade do sêmen, produção de espécies reativas de oxigênio (ROS) e atividade mitocondrial do sêmen bovino criopreservado. Foram utilizados 195 palhetas de 0,5 mL de cinco touros Holstein Friesian (39 palhetas por touro). As amostras passaram por oito a 22 anos de armazenamento e foram processadas sob protocolo padrão com Tris-gema de ovo e armazenadas em nitrogênio líquido. As temperaturas de descongelamento foram T1: 36 °C, T2: 38 °C, T3: 40 °C, cada uma por 30 segundos em banho-maria. Pós-descongelamento, a motilidade e cinética dos espermatozoides, morfologia, integridade estrutural da membrana (SMI), integridade funcional da membrana (FMI), integridade acrossomal (AI), ROS e potencial de membrana mitocondrial (ΔΨM) foram avaliados. Modelos lineares generalizados foram ajustados. Cada modelo incluiu os efeitos de touro, tempo de armazenamento e tratamento. A normalidade dos dados foi avaliada pelo teste de Shapiro-Wilk e as médias comparadas pelo teste de Tukey. T2 e T3 apresentaram resultados mais elevados para a maioria dos parâmetros de motilidade e cinemática espermática, SMI (%) (T1 41,9 ± 2,3; T2 45,7 ± 1,9; T3 47,4 ± 2,8), ROS (RFU/min) (T1 0,026 ± 0,007; T2 0,032 ± 0,001; T3 0,031 ± 0,001) e alto ΔΨM (RFU x 103) (67,1 ± 0,4; 71,3 ± 0,4; 74,2 ± 0,4) (P < 0,05). No entanto, T1 apresentou maior FMI (%) (39,3 ± 2,3) em comparação a T2 (34,0 ± 1,9) (P < 0,05), mas não foi diferente do T3 (38,4 ± 2,2) (P > 0,05). Conclui-se que as temperaturas de descongelamento de 38 °C e 40 °C produzem um aumento na motilidade, cinética, integridade de membrana, atividade mitocondrial e ROS do sêmen bovino criopreservado, em comparação com o uso mais convencional de uma temperatura de descongelamento de 36 °C.

Relationship of Linoleic and Alpha-Linolenic Acids on the Productive Performance and Serum Biochemical Profile of Japanese Quail Breeders

Linoleic (LA, 18:2) and alpha-linolenic (ALA, 18:3) acids are omega-6 and omega-3 polyunsaturated fatty acids considered essential to human and animal health. The optimum LA/ALA ratio for the production of fertile eggs in Japanese quail breeders has been little investigated. Thus, this study aimed to assess the effects of LA/ALA ratio on productive performance, egg quality, serum biochemical profile, body composition, and organ weight in Japanese quail. A completely randomized design was used. Birds were distributed into five treatments consisting of different LA/ALA ratios (1.48:1, 4.57:1, 7.63:1, 10.69:1, and 13.75:1), obtained by adding soybean (LA) and flaxseed (ALA) oils to the feed. Productive performance and egg quality were assessed in three cycles of 28 days each. At the end of the experiment, the birds were slaughtered and evaluated for biochemical profile, genital organ weights, and body composition. Data were subjected to analysis of variance and regression (p<0.05). LA/ALA ratio had no effect on productive performance or egg quality. Blood cholesterol in females and males and total triglycerides in females showed a quadratic response. Breeders fed the highest level of flaxseed oil (1.48:1) had the best serum levels of cholesterol and total triglycerides. Live weight and relative organ weights were not influenced by LA/ALA ratio. Differences in ash and crude protein levels were observed between groups, with LA increasing the deposition of these nutrients. It was concluded that LA/ALA ratio didn't affect productive performance or egg quality. However, based on the results of body composition, serum triglycerides, and cholesterol, it is recommended to use an LA/ALA ratio of 1.48:1 in diets.(AU)

Consumer Preference and Quality Characteristics of Different-category Eggs Sold at Supermarkets in Rio de Janeiro / Preferência do Consumidor e Características de Qualidade em Ovos de Diferentes Categorias Comercializados nos Supermercados do Rio de Janeiro

This study approached the consumer preference and characteristics of eggs from various categories sold at supermarkets in Rio de Janeiro. The study was performed in three phases. In the first one, 180 'caipira' eggs were randomly acquired from three supermarkets considering the consumers' socioeconomic profile (middle, upper, and lower class). In the second phase, 456 eggs from conventional, free-range, 'caipira' and omega-3 enriched categories were obtained without considering the socioeconomic condition. After the acquisition, the eggs were taken for further analyses made the next day. The last phase was based on the perception and prevalence of consumers found in the second stage. This time, 443 consumers answered a Google Forms questionnaire. 'Caipira' eggs sold at supermarkets frequented by upper-class consumers maintained a better quality. When social class was discarded as a criterion, eggs from 'caipira', free-range, organic, and omega-3 enriched systems showed inferior quality compared to conventional eggs. The consumer preferences indicated that much misinformation regarding technical aspects of egg production persists, despite the increasing consumption of this protein source. In addition, the study revealed that many consumers still think there are hormone inputs in poultry farming, and they know very little about the production process or the differences among the egg categories for sale at Brazilian supermarkets.(AU)

O estudo abordou a preferência de consumo e as características de qualidade em ovos de diversas categorias, comercializados em supermercados do Rio de Janeiro e foi realizado em três etapas. Na primeira, foram adquiridos de forma inteiramente casualizada, 180 ovos marrons apenas de categoria caipira, em três diferentes supermercados, considerando o perfil socioeconômico dos consumidores (classe média, baixa e alta). Na segunda, foram adquiridos pelos mesmos critérios e de supermercados distintos, 456 ovos marrons de várias categorias (convencional, free-range, caipira, orgânicos e enriquecidos (ômega-3), sem considerar a condição socioeconômica dos consumidores. Após aquisição, foram levados para análise, que foi realizada no dia seguinte. A terceira etapa, se baseou na percepção e prevalência de consumo de ovos da mesma categoria da segunda etapa, em entrevista na forma de questionário disponibilizado na plataforma Google Forms, para um total de 443 participantes. Ovos de categoria caipira, comercializados em mercados frequentados por consumidores de classe alta, mantiveram melhor a qualidade. Quando não foi considerada a classe social, ovos free-range, caipira, orgânico e enriquecidos apresentaram qualidade inferior, comparado aos convencionais. A preferência de consumo abordada, indicou que o aumento no consumo de ovos, é acompanhado de muita desinformação acerca de vários aspectos inerentes a essa proteína e de forma alarmante, revelou que muitos consumidores ainda acreditam na participação de hormônios na produção de aves, além de pouco ou nada conhecerem sobre como esse alimento é produzido e as diferenças entre as diversas categorias de ovos expostos à venda nos supermercados brasileiros.(AU)

Utilização de métodos alternativos como indutor de muda forçada em codornas poedeiras / Use of alternative methods as an inducer of forced molting in laying quail

Objetivou-se avaliar métodos alternativos de restrição alimentar qualitativa e quantitativa em comparação à técnica convencional de muda forçada em codornas japonesas para o segundo ciclo de produção. O período de muda forçada teve duração de 10 dias e dois períodos de 21 dias de pós-muda. Foram utilizadas 72 codornas japonesas fêmeas, emfinal de produção com 72 semanas deidade. As aves foram distribuídas em delineamento inteiramente casualizado com três tratamentos e quatro repetições cada, com seiscodornas por repetição. Os tratamentos experimentais foram:T1 ­aves submetidas a três dias de jejum com posterior fornecimento de ração de postura à vontade por setedias; T2 ­aves que receberam alimentação controlada (10 g/ave/dia) por 10 dias; T3 ­aves que receberam farelo de arroz à vontade por 10 dias. Durante todo o experimento todasas aves foram submetidas a iluminação natural com média de 12 horas de luz diária e água a vontade e após os 10 dias de muda foi fornecido ração de postura a vontade. A utilização do T2 (10 g/ave/dia de ração de postura) e de farelo de arroz como alimentoalternativo no programa de muda forçada foi viável. Mesmo a perda de peso sendo abaixo do recomentado, as aves que receberam 10 g de ração ave/dia e farelo de arroz à vontade apresentaram resultados de desempenho e qualidade do ovo pós muda semelhantes àsaves que ficaram em jejum, além de possibilitar melhores condições de bem-estar animal.(AU)

The objective was to evaluate alternative methods of qualitative and quantitative feed restriction compared to theconventional technique of forced moulting in Japanese quails for the second production cycle. The forced moulting period lasted 10 days and two 21-day post-molt periods. 72 female Japanese quails were used, at the end of production at 72 weeks of age. Thebirds were distributed in a completely randomized design with three treatments and four replications each, with sixquails per replicate. The experimental treatments were: T1 ­birds submitted to three days of fasting with subsequent provision of layingfeed ad libitum for sevendays; T2 ­birds that received controlled feeding (10 g/bird/day) for 10 days; T3 ­birds that received rice bran ad libitum for 10 days. Throughout the experiment, all birds were submitted tonatural lighting with an average of12hours of daily light and water ad libitum and after 10 days of molting, laying feed was provided ad libitum. The use of T2 (10 g/bird/day of laying ration) and ricebran as an alternativefood in the forced molt program was feasible. Even the weight loss being below the recommended, the birds that received 10 g of poultry feed/day and rice bran ad libitum showed similar post-moult performance and egg quality results to birds that were fasted, in addition to enabling better conditions. of animal welfare.(AU)