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)

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.

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)

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)

Bacillus Cereus in Eggshell: Enterotoxigenic Profiles and Biofilm Production

A study was carried out with the objective of determining the presence of Bacillus cereus in eggshells commercialized in Mexico, the enterotoxigenic profile of the isolated strains, and the production of biofilms in different materials as well as in the eggshell. 1000 chicken eggs from four commercial brands were collected from markets and supermarkets located in the city of Chilpancingo, Mexico. Bacillus cereus was isolated from the eggshell. The molecular identification was by amplification of the gyrB gene and the enterotoxigenic profiles by the amplification of the cytK, ces, nheABC, and hblABD genes, in addition to the amplification of the tasA and sipW genes associated with the production of biofilms. In different materials and in eggshells, the production of biofilms was evaluated. The microbiological and molecular analysis of B. cereus yielded a frequency of 5.5% (55/1000), this was higher in brand III (11.6%, p=0.0001) and white eggshell (7.6%, 38/500, p≤0.001) and by marketing source, it was similar between market (5.2% / 26/500) and supermarket (5.8%, 29/500). The most common was the toxigenic profile A (23/55). Biofilm production is high in PVC in relation to other materials (p<0.0001), and the frequency of the related genes tasA and sipW was 72.7% and 40% respectively; the highest production was related to the tasA gene; in eggshell, most of the strains (54/55) were able to produce biofilm. Strains of B. cereus with toxigenic potential circulate and persist in this product, which shows the need for sanitary regulation in the country.(AU)

Effect of Temperature and Feeding Time on Shell Thickness

The objective of this study was to assess the effect of ambient temperature (T) and feeding time (FT) on eggshell thickness (ST) and egg weight (EW) of broiler breeder hens. Thirty 44-week-old Ross 308 broiler breeder hens were randomly distributed into six environmentally controlled chambers and kept in individual cages. Three thermal treatments were applied: 20 ºC (T1), cyclic 20-30 ºC (30 °C between 1000 h and 1800 h) (T2), and 30 ºC (T3). Birds received 180 g of commercial breeder food at 0730 h (FT1) or 1530 h (FT2). There were two replications per treatment and egg collection was performed for seven days. The eggs from the birds at T1 and T2 fed at 1530 h (T1FT2 and T2FT2 respectively) were significantly heavier than those laid by hens at the same T when fed in the morning (T1FT1 and T2FT1); eggs from T1FT1 and T2FT1 were heavier than the eggs from T3, but there were no significant differences between them. Both T and FT had significant effects on ST, but no significant interactions were found. Birds fed at 1530 h had the highest ST, whilst birds at T3 showed the lowest. Birds on T2 produced the thickest shells due to a higher ST in birds fed at 1530 h. Birds fed at 1530 h consumed their food between 1800 h and 2030 h, resulting in a higher dietary Ca2 + available during shell mineralization. The effect of FT and biphasic T treatments on ST in feed restricted broiler breeders should be interpreted considering the length of the high T phase to the actual food consumption time.(AU)

The Effect of Dietary Glucose Oxidase Supplementation on Production Performance, Egg Quality and Nutrient Digestibility in Laying Hens

The study was conducted to investigate the effect of GOX on performance, egg quality, and nutrient digestibility in laying hens. In total, 432, 50-week-old Hy-Line brown breeder hens were assigned into four treatments, and fed a basal diet with GOX at 0, 100, 200 and 300 units for 10 weeks, respectively. A Quadratic decrease in FI in week 3 (p<0.05) and linear increase in egg production in week 6 to 10 and overall experiment period (p<0.05) and Quadratic increase in egg production in week 7 (p<0.05), a linear decrease in broken egg rate in week 6 (p<0.05) a quadratic increase in egg weight on day 14 (p<0.05), alinear increase in egg weight on day 28 (p<0.05), and linear decrease in yolk color on day 7 (p<0.05), a linear increase in yolk color on day 42 and day 70 (p<0.05), and linear increase in haugh unit on day 28 and 70 (p<0.05), a linear increase albumen height on day 28 and day 56 (p<0.05), and linear decrease in shell color on day 14 (p<0.05) and day 28(p<0.05), a linear and quadratic increases in eggshell strength and eggshell thickness on day 56 (p<0.05), and linear increase in eggshell strength and eggshell thickness on day 70 (P0.05) were observed with the addition of GOX the the diet. Conclusion: This study suggested that the supplementation of GOX may have beneficial effects on feed intake and egg quality in laying hens.(AU)

The Effect of Supplementing Tea Polyphenols on Yolk Cholesterol and Production Performance of Laying Hens During the Egg-laying Period

This study aimed to investigate the effect of supplementing 300 mg/kg tea polyphenols (TP) on yolk cholesterol content and production performance of laying hens during the egg-laying period. A total of 600 Roman laying hens aged 24 weeks were randomly divided into two dietary treatment groups. The feeding experiment lasted for 48 weeks. Layers fed basal diet supplemented with 0 (control group) and 300mg/kg TP (TP group) diet, respectively. The yolk cholesterol content, laying performance, and egg quality were determined at 28, 38, 48, 58, and 68 weeks of age. The yolk cholesterol content in the TP group was significantly decreased at 28-68 weeks of age (p<0.01), compared to the control group. There was a significant increase in laying rate in the TP group at 38 weeks of age (p<0.05), compared to the control group, while no significant differences during the other laying periods were obtained (p>0.05). The FCR significantly decreased in the TP group at 38 weeks of age whereas AEW significantly increased in the TP group at 58 weeks of age (p<0.05). Similarly, the eggshell thickness and eggshell strength in the TP group significantly increased (p<0.05), compared with the control group at 38 weeks of age. The albumen height and Haugh unit significantly increased at 28 weeks of age (p<0.05). In conclusion, the results showed that the diet supplemented with 300 mg/kg TP had positive effects on production performance of layers during the egg-laying period, and could lessen yolk cholesterol content significantly at 28-68 weeks of age.(AU)

Protease Supplementation in the Diet of Light Laying Hens

This work was developed to evaluate the impact of the addition of proteases on the performance characteristics, egg quality, relative weight of digestive organs, and intestinal morphometry of laying hens. 390 Hy Line W36® hens were allocated into five treatments and six replicates with 13 animals. The treatments were: 1) Control (standard formulation), 2) Negative control A - NCA (nutritional reduction according to protease A matrix), 3) Negative control B - NCB (nutritional reduction according to protease B matrix), 4) NCA+protease A (0.250 g/kg of feed) and 5) NCB+protease B (0.125 g/kg of feed). Hens fed the NCA, NCB, and NCA+protease A diets showed reductions in feed intake and egg mass. The addition of protease B provided better results for egg production in both percentage and per dozen as compared to the group fed with the NCA+protease A diets. The hens subjected to diets NCA and NCB showed eggs with a reduced eggshell and thickness percentage. However, supplementation with proteases A and B improved these parameters to values similar to the controls. There was no significant effect of the treatments on the relative weight of the liver, proventricle, gizzard, pancreas, and small intestine. However, the addition of protease A resulted in a decreased value for the relative weight of the large intestine. The jejunum and ileum crypt depths were, respectively, smaller in hens fed the control diet in relation to the NCB diet and the NCA and NCB diets. As it can be concluded, Protease B supplementation provided the best performance results.(AU)

Impact of Selenium-Supplemented Diets on Egg Morphometry and Quality in Four Varieties of Indigenous Aseel Chicken

ABSTRACT The present study aimed at evaluating the effects of dietary selenium (Se) supplementation on egg morphometric and quality traits in Aseel chicken. In total, 84 adult molted Aseel hens, comprising 4 varieties (Lakha, Mushki, Peshawari, and Mianwali), were divided into 3 dietary treatments (organic at 0.30 ppm, inorganic at 0.30 ppm, and without selenium) with 7 replicates (1 bird in each) under randomized complete block design. Data were analyzed using factorial ANOVA and means were compared using Duncans Multiple Range Test. The results indicated greater egg length in Mushki and Mianwali, lower egg breadth in Lakha, the highest (p0.05) egg volume and surface area in Mianwali, and higher shape index in Lakha and Peshawari. Lakha had the highest Haugh unit and lower eggshell thickness with and without membrane than the other three varieties. Interaction of Se sources and Aseel varieties exhibited the highest (p0.05) egg volume and surface area in Mianwali variety when fed on organic Se supplemented diet. Similarly, the interaction showed the highest eggshell thickness with membrane in Peshawari and without membrane in Mianwali when fed on inorganic Se supplemented diet. From the findings, it can be concluded that egg physical characteristics of Mianwali variety hens can be improved by the supplementation of Se-enriched yeast, as an organic Se source, in the diet.

Influence of Low and High-density Diets with Yeast Supplementation on Feed Intake, Nutrient Digestibility, Egg Production and Egg Quality in Hy-line Brown Laying Hens

A total of 432 laying hens (40 weeks old) were used in a 10- weeks feeding trial. The birds were randomly assigned to 1 of 4 treatments with 18 replications (6 birds per replication) in a 2×2 factorial arrangement with low-density diet (LD), and high density (HD) diets supplemented with or without (0.1 %) of yeast. Laying hens feed intake during the 5th, 6th and 10th weeks has significantly increased (p<0.05) in LD diet and HD diet supplemented with (0.1 %) of yeast supplementation. However, egg production and broken rate was not affected with or without yeast and density diet. The quality of egg and shell color during the 5th, 6th, and 7th weeks has significantly reduced (p<0.05) by yeast supplementation with HD and LD diet. Eggshell strength was significantly improved at week 4, moreover albumin height was also significantly improved by yeast supplementation diets at week 5. During week 1 and 2 the yolk color was higher in LD diet and HD diet compared with yeast supplementation. However, eggshell strength was significantly improved on HD diets than LD diets during the 4th and 7th weeks. Eggshell color and albumen height were significantly decreased in laying hens fed HD or LD diets during week 5 and 6. The apparent total tract digestibility (ATTD) of dry matter (DM), nitrogen (N), and Energy was not affected (p<0.05) by laying hens fed with or without yeast and HD than LD diets. In summary, 0.1% of yeast supplementation proved a positive impact on feed intake and egg quality of layer chicken.(AU)

Influence of Low and High-density Diets with Yeast Supplementation on Feed Intake, Nutrient Digestibility, Egg Production and Egg Quality in Hy-line Brown Laying Hens

A total of 432 laying hens (40 weeks old) were used in a 10- weeks feeding trial. The birds were randomly assigned to 1 of 4 treatments with 18 replications (6 birds per replication) in a 2×2 factorial arrangement with low-density diet (LD), and high density (HD) diets supplemented with or without (0.1 %) of yeast. Laying hens feed intake during the 5th, 6th and 10th weeks has significantly increased (p<0.05) in LD diet and HD diet supplemented with (0.1 %) of yeast supplementation. However, egg production and broken rate was not affected with or without yeast and density diet. The quality of egg and shell color during the 5th, 6th, and 7th weeks has significantly reduced (p<0.05) by yeast supplementation with HD and LD diet. Eggshell strength was significantly improved at week 4, moreover albumin height was also significantly improved by yeast supplementation diets at week 5. During week 1 and 2 the yolk color was higher in LD diet and HD diet compared with yeast supplementation. However, eggshell strength was significantly improved on HD diets than LD diets during the 4th and 7th weeks. Eggshell color and albumen height were significantly decreased in laying hens fed HD or LD diets during week 5 and 6. The apparent total tract digestibility (ATTD) of dry matter (DM), nitrogen (N), and Energy was not affected (p<0.05) by laying hens fed with or without yeast and HD than LD diets. In summary, 0.1% of yeast supplementation proved a positive impact on feed intake and egg quality of layer chicken.

Impact of Selenium-Supplemented Diets on Egg Morphometry and Quality in Four Varieties of Indigenous Aseel Chicken

The present study aimed at evaluating the effects of dietary selenium (Se) supplementation on egg morphometric and quality traits in Aseel chicken. In total, 84 adult molted Aseel hens, comprising 4 varieties (Lakha, Mushki, Peshawari, and Mianwali), were divided into 3 dietary treatments (organic at 0.30 ppm, inorganic at 0.30 ppm, and without selenium) with 7 replicates (1 bird in each) under randomized complete block design. Data were analyzed using factorial ANOVA and means were compared using Duncans Multiple Range Test. The results indicated greater egg length in Mushki and Mianwali, lower egg breadth in Lakha, the highest (p≤0.05) egg volume and surface area in Mianwali, and higher shape index in Lakha and Peshawari. Lakha had the highest Haugh unit and lower eggshell thickness with and without membrane than the other three varieties. Interaction of Se sources and Aseel varieties exhibited the highest (p≤0.05) egg volume and surface area in Mianwali variety when fed on organic Se supplemented diet. Similarly, the interaction showed the highest eggshell thickness with membrane in Peshawari and without membrane in Mianwali when fed on inorganic Se supplemented diet. From the findings, it can be concluded that egg physical characteristics of Mianwali variety hens can be improved by the supplementation of Se-enriched yeast, as an organic Se source, in the diet.(AU)

Impact of Selenium-Supplemented Diets on Egg Morphometry and Quality in Four Varieties of Indigenous Aseel Chicken

The present study aimed at evaluating the effects of dietary selenium (Se) supplementation on egg morphometric and quality traits in Aseel chicken. In total, 84 adult molted Aseel hens, comprising 4 varieties (Lakha, Mushki, Peshawari, and Mianwali), were divided into 3 dietary treatments (organic at 0.30 ppm, inorganic at 0.30 ppm, and without selenium) with 7 replicates (1 bird in each) under randomized complete block design. Data were analyzed using factorial ANOVA and means were compared using Duncan’s Multiple Range Test. The results indicated greater egg length in Mushki and Mianwali, lower egg breadth in Lakha, the highest (p≤0.05) egg volume and surface area in Mianwali, and higher shape index in Lakha and Peshawari. Lakha had the highest Haugh unit and lower eggshell thickness with and without membrane than the other three varieties. Interaction of Se sources and Aseel varieties exhibited the highest (p≤0.05) egg volume and surface area in Mianwali variety when fed on organic Se supplemented diet. Similarly, the interaction showed the highest eggshell thickness with membrane in Peshawari and without membrane in Mianwali when fed on inorganic Se supplemented diet. From the findings, it can be concluded that egg physical characteristics of Mianwali variety hens can be improved by the supplementation of Se-enriched yeast, as an organic Se source, in the diet.

Relationship between the level and the action period of fiber in diets to laying hens

The aim of the present study was to evaluate the relationship between the level of fiberand its action period in diets to laying hens on performance and egg quality. 180 Hisex white hens (65 weeks-old) were randomly allocated to 3 groups of 60 birds each, comprising 10 replicates of six birds per treatment. The experimental design was factorial scheme considering three levels of fiber(2.50, 4.87 and 7.24%) in birds diets, and three action periods of this fiber(short -21 days, medium -56 days, and long -105 days) in the feed. The estimates of treatments were firstly subjected to ANOVA and a subsequent Tukey test at 5%. Birds fed diets with moderate levels of fiber(4.87%) presented better (p<0.05) performance. High levels of fibercaused a significant reduction in performance.Birds fed diets with low and moderate levels of fiberproduced eggs with better (p<0.05) quality. High levels of fibercaused a significant reduction in egg quality.The exposure of birds to diets with fiberfor long-term caused a negative effect (p<0.05) on performance, egg weight and percentage of its main structures, albumen height, yolk height, eggshell thickness, and the specific gravity.(AU)

Relationship between the level and the action period of fiber in diets to laying hens

The aim of the present study was to evaluate the relationship between the level of fiberand its action period in diets to laying hens on performance and egg quality. 180 Hisex white hens (65 weeks-old) were randomly allocated to 3 groups of 60 birds each, comprising 10 replicates of six birds per treatment. The experimental design was factorial scheme considering three levels of fiber(2.50, 4.87 and 7.24%) in birds’ diets, and three action periods of this fiber(short -21 days, medium -56 days, and long -105 days) in the feed. The estimates of treatments were firstly subjected to ANOVA and a subsequent Tukey test at 5%. Birds fed diets with moderate levels of fiber(4.87%) presented better (p<0.05) performance. High levels of fibercaused a significant reduction in performance.Birds fed diets with low and moderate levels of fiberproduced eggs with better (p<0.05) quality. High levels of fibercaused a significant reduction in egg quality.The exposure of birds to diets with fiberfor long-term caused a negative effect (p<0.05) on performance, egg weight and percentage of its main structures, albumen height, yolk height, eggshell thickness, and the specific gravity.

Prediction of Egg Weight from External Egg Traits of Guinea Fowl Using Multiple Linear Regression and Regression Tree Methods

The study was done to predict egg weight from the external traits of the Guinea fowl egg using the statistical methods of multiple linear regression (MLR) and regression tree analysis (RTA). A total of 110 eggs from a flock of 23-week-old Guinea fowl were evaluated. Egg weight (EW) and external traits: eggshell weight (ESW), egg polar diameter (EPD), egg equatorial diameter (EED), egg shape index (ESI), and egg surface area (ESA) were measured. Descriptive statistics, Pearson correlation coefficients, and regression equations using the MLR were obtained; additionally, a RTA was done using the CHAID algorithm with the SPSS software (IBM ver. 22). EW presented positive correlations (p 59.03 cm2 and a polar diameter > 5.10 cm. The proposed statistical methods can be used to reliably predict the egg weight of Guinea fowl.

Prediction of Egg Weight from External Egg Traits of Guinea Fowl Using Multiple Linear Regression and Regression Tree Methods

The study was done to predict egg weight from the external traits of the Guinea fowl egg using the statistical methods of multiple linear regression (MLR) and regression tree analysis (RTA). A total of 110 eggs from a flock of 23-week-old Guinea fowl were evaluated. Egg weight (EW) and external traits: eggshell weight (ESW), egg polar diameter (EPD), egg equatorial diameter (EED), egg shape index (ESI), and egg surface area (ESA) were measured. Descriptive statistics, Pearson correlation coefficients, and regression equations using the MLR were obtained; additionally, a RTA was done using the CHAID algorithm with the SPSS software (IBM ver. 22). EW presented positive correlations (p<0.0001) with ESA (r = 0.72), EPD (r = 0.65), and EED (r = 0.49). EW can be predicted through MLR using ESA as a predictor variable (R2 = 72%). Predictive accuracy improves when adding EPD and EED traits to the model (R2 = 75%). The RTA built a diagram using ESA, EED, and EPD as significant independent variables; of these, the most important variable was ESA (F = 50,295, df1 = 4, and df2 = 105; Adj. p<0.000) and the variation explained for EW was 74%. Likewise, the RTA showed that the highest egg weight (41.818 g) is obtained from eggs with a surface area > 59.03 cm2 and a polar diameter > 5.10 cm. The proposed statistical methods can be used to reliably predict the egg weight of Guinea fowl.(AU)

Nanocomposite of Ag-Doped ZnO and Ag2O nanocrystals in control of Salmonella Heidelberg biofilms formed in commercial egg / Nanocompostos de Ag-Doped ZnO e nanocristais de Ag2O no controle da formação de biofilmes de Salmonella Heidelberg em ovos comerciais

Salmonella spp. is an important causal agent of salmonellosis in humans. Controlling Salmonella spp. in eggs is important as the bacterium passes through the shell to an embryo and remains in the terrain. Disinfection is usually performed by using several sanitizers. However, novel, more efficient ways of controlling this agent have been studied with advances in nanotechnology, including nanoparticles. Preliminary studies of nanoparticles have shown they are successful in controlling such microorganisms. Standardizing the ideal concentration of this nanocomposite is fundamental for optimum efficiency in the control of Salmonella spp. In this study, eggs from commercial laying chickens were purchased from local trade and treated in laboratory with silver and zinc nanoparticles in different concentrations. Biofilm was formed 24 hours after that; then, the eggs were washed for the removal of free bacteria. Conventional microbiology was performed to isolate Salmonella spp., and PCR was performed to identify colonies. The effectiveness of using nanocomposite of silver oxide with silver-doped zinc oxide (ZnO:Ag-AgO) was evaluated in different concentrations to prevent the formation of eggshell biofilms.

As Salmonellas spp. são importantes agentes causadores de salmonelose em humanos. O controle da Salmonella spp. é importante, pois a bactéria ultrapassa a barreira da casca atingindo o embrião e infecta lotes de aves que podem levar a infecção ao ser humano. A desinfecção costuma ser feita por vários sanitizantes; porém, com os avanços da nanotecnologia, formas novas e mais eficientes de controle desse agente estão sendo estudadas, como as nanopartículas. Estudos preliminares dessas nanopartículas têm mostrado o sucesso de seu uso no controle de microrganismos. A padronização da concentração ideal de uso desse nanocomposto é fundamental para a máxima eficiência no controle de Salmonella spp. Ovos vermelhos oriundos de postura comercial foram comprados no comércio local e tratados em laboratório com as nanopartículas em diferentes concentrações; após 24 horas, formaram o biolfilme. Os ovos foram lavados para a retirada das bactérias livres. Realizaram-se exame microbiológico convencional, para isolamento de Salmonella spp., e PCR, para identificação das colônias. O objetivo deste artigo foi avaliar a eficácia da utilização de nanocompostos de óxido de prata com óxido de zinco dopado com óxido de prata (ZnO: Ag-Ago) em diferentes concentrações na prevenção da formação de biofilmes na casca dos ovos.

Nanocomposite of Ag-Doped ZnO and Ag2O nanocrystals in control of Salmonella Heidelberg biofilms formed in commercial egg / Nanocompostos de Ag-Doped ZnO e nanocristais de Ag2O no controle da formação de biofilmes de Salmonella Heidelberg em ovos comerciais

Salmonella spp. is an important causal agent of salmonellosis in humans. Controlling Salmonella spp. in eggs is important as the bacterium passes through the shell to an embryo and remains in the terrain. Disinfection is usually performed by using several sanitizers. However, novel, more efficient ways of controlling this agent have been studied with advances in nanotechnology, including nanoparticles. Preliminary studies of nanoparticles have shown they are successful in controlling such microorganisms. Standardizing the ideal concentration of this nanocomposite is fundamental for optimum efficiency in the control of Salmonella spp. In this study, eggs from commercial laying chickens were purchased from local trade and treated in laboratory with silver and zinc nanoparticles in different concentrations. Biofilm was formed 24 hours after that; then, the eggs were washed for the removal of free bacteria. Conventional microbiology was performed to isolate Salmonella spp., and PCR was performed to identify colonies. The effectiveness of using nanocomposite of silver oxide with silver-doped zinc oxide (ZnO:Ag-AgO) was evaluated in different concentrations to prevent the formation of eggshell biofilms.(AU)

As Salmonellas spp. são importantes agentes causadores de salmonelose em humanos. O controle da Salmonella spp. é importante, pois a bactéria ultrapassa a barreira da casca atingindo o embrião e infecta lotes de aves que podem levar a infecção ao ser humano. A desinfecção costuma ser feita por vários sanitizantes; porém, com os avanços da nanotecnologia, formas novas e mais eficientes de controle desse agente estão sendo estudadas, como as nanopartículas. Estudos preliminares dessas nanopartículas têm mostrado o sucesso de seu uso no controle de microrganismos. A padronização da concentração ideal de uso desse nanocomposto é fundamental para a máxima eficiência no controle de Salmonella spp. Ovos vermelhos oriundos de postura comercial foram comprados no comércio local e tratados em laboratório com as nanopartículas em diferentes concentrações; após 24 horas, formaram o biolfilme. Os ovos foram lavados para a retirada das bactérias livres. Realizaram-se exame microbiológico convencional, para isolamento de Salmonella spp., e PCR, para identificação das colônias. O objetivo deste artigo foi avaliar a eficácia da utilização de nanocompostos de óxido de prata com óxido de zinco dopado com óxido de prata (ZnO: Ag-Ago) em diferentes concentrações na prevenção da formação de biofilmes na casca dos ovos.(AU)