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Gabor Milisits - One of the best experts on this subject based on the ideXlab platform.
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Effect of starting body fat content and genotype of laying hens on the changes in their live weight, body fat content, Egg production and Egg Composition during the first Egg-laying period.
British poultry science, 2015Co-Authors: Gabor Milisits, J. Ujvari, Tamás Donkó, Eszter Szentirmai, Z. Budai, S. Áprily, G. Bajzik, Zoltán SütőAbstract:A total 120 laying hens (60 TETRA BLANCA white Egg layers and 60 TETRA SL brown Egg layers) were selected from 250 TETRA BLANCA and 250 TETRA SL pullets based on their predicted body fat content by means of computed tomography (CT) at 16 weeks of age. Three groups of pullets were chosen for the investigation with the highest (n = 20), lowest (n = 20) and average (n = 20) body fat content. Changes in the live weight, body fat content, Egg production and Egg Composition of the chosen animals were recorded at 32, 52 and 72 weeks of age. Based on the results, it was established that differences in starting body fat content of the hens remained the same during the experimental period. The differences between the two extreme groups were statistically significant at each age. The starting body fat content of the hens affected the rate of Egg production, i.e. hens with high starting body fat content produced 11-14 Eggs fewer than the hens with a low or average body fat content but had no effect on the Composition of the Eggs. Genotype affected almost all of the examined traits: TETRA BLANCA hens had lower live weight and higher body fat content during the experimental period and produced fewer Eggs with lower albumen and higher yolk, dry matter and crude fat content than the TETRA SL hens.
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Comparison of changes in production and Egg Composition in relation to in vivo estimates of body weight and Composition of brown and white Egg layers during the first Egg-laying period
British poultry science, 2013Co-Authors: Eszter Szentirmai, Gabor Milisits, J. Ujvari, Tamás Donkó, Imre Repa, Z. Budai, T. Fülöp, Zoltán SütőAbstract:1. The aim of this study was to compare the changes in the production and in the body and Egg Composition of 45 TETRA SL brown Egg layers and 45 TETRA BLANCA white Egg layers during the first Egg-laying period.2. Changes in the body Composition of the hens were followed in vivo by means of computed tomography (CT) four-weekly, between 20 and 72 weeks of age. The measurements covered the whole body of the hens using overlapping 10 mm slice thicknesses on a Siemens Somatom Emotion 6 multislice CT scanner.3. The yolk, albumen and shell ratio of the Eggs, produced on the days of the CT measurements by the hens, were determined and their Composition was analysed chemically.4. The body fat content of the hens increased continuously until 44 weeks of age and plateaued thereafter in both genotypes. However, the body fat content of the white Egg layers was always higher than that of the brown Egg layers.5. The yolk ratio and the dry matter and crude fat content of the Eggs of white Egg layers were higher than the ...
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A tojásösszetétel, a keltethetőség, valamint a kikelő madarak fejlődése és termelése közötti összefüggések in vivo vizsgálata komputer tomográffal kettőshasznosítású tyúk genotípusokban = In vivo examination of the correlations between hen's Egg comp
2011Co-Authors: Gabor Milisits, Tamás Donkó, Zoltán Sütő, Antonella Dalle Zotte, András SzabóAbstract:A kutatasi program kereteben kidolgoztuk a tyuktojasok CT vizsgalatanak metodikajat. Meghataroztuk a legjobban ertekelhető felvetelek elkeszitesehez szukseges technikai parametereket es az egyidejűleg vizsgalhato tojasok szamat. A tojasok sargaja aranyanak meghatarozasahoz egy uj szoftvert fejlesztettunk, ami lehetőve tette a keresztmetszeti kepek gyors es automatikus ertekeleset. Megallapitottuk, hogy a kisebb sargaja, azaz nagyobb feherje arannyal rendelkező tojasokbol nagyobb sulyu csibek kelnek mindket ivarban. A kakasok eseteben a nagyobb feherje aranyu tojasokbol kelt madarak a testsulybeli folenyuket a hizlalas vegeig megőriztek, mig a jercek kelesi sulyaban megfigyelt kulonbsegeket a hizlalas vegen mar nem lehetett kimutatni. A keltetőtojasok sargaja aranya szignifikans hatassal volt viszont a jercek testzsirtartalmanak neveles alatti alakulasara, ami kihatassal volt a kesőbbi termelesukre. A kutatas soran megallapitottuk, hogy a tyuktojasok osszetetele a CT hasznalataval pontosabban becsulhető, mint a korabban alkalmazott TOBEC modszerrel. A tojasok osszetetele szignifikans hatassal van a csibek kelesi sulyanak es testosszetetelenek alakulasara, ami kihatassal van a kesőbbi fejlődesukre es ezen keresztul a termelesukre. Mindezek alapjan indokoltnak tűnik a tojasosszetetel in vivo meghatarozasanak tovabbi pontositasa, a tojasosszetetel, a keltethetőseg, valamint a kikelő madarak fejlődese es termelese kozotti osszefuggesek tovabbi tisztazasa erdekeben. | In the frame of this research project the methodology of CT examination of hen’s Eggs was developed. The optimal technical parameters and the number of simultaneously scanable Eggs were determined in order to obtain the best quality CT images for the evaluation. For the fast and automatic determination of yolk ratio a new software was developed. By separating Eggs with different predicted yolk ratios it was established that chicks hatched from Eggs with low yolk – high albumen – content had higher liveweight at hatching in both sexes. This higher liveweight was also observed at the end of the rearing period in the case of the cocks, but it was not observable in the case of the pullets. However, the yolk content of the Eggs had a significant effect on the body fat content of the pullets, which affected the latter production of these birds. During this research work it was also established that the predictability of the Composition of hen’s Eggs is more accurate by means of the CT than it was formerly by means of the TOBEC method. The Composition of the Eggs has a significant effect on the liveweight and body Composition of the chicks at hatching, which has an effect on their latter development and production. Therefore, based on these results it seems to be necessary to improve the accuracy of the in vivo prediction of Egg’s Composition in order to clarify the correlations between Egg Composition, hatchability and hatched bird’s development and production more precisely.
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Possibilities and Deliminations In Vivo Determination of Egg Composition
Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Animal Science and Biotechnologies, 2010Co-Authors: Gabor Milisits, Tamás Donkó, Miklós Emri, Gábor Opposits, Attila Orbán, Zoltán Sütő, Imre RepaAbstract:The aim of these experiments was to examine the applicability of two different methods (TOBEC and CT) for the in vivo prediction of Egg Composition. In the first experiment the electrical conductivity of 46 hen's Eggs was measur ed by means of the TOBEC (Total Body Electrical Conductivity) method and correlations were calculat ed between the measured values and different Egg components (dry matter, protein, fat). In the secon d experiment 120 hen's Eggs were scanned by CT (computer tomography), in order to develop the CT measurement protocol and to determine correlations between the information content of the CT images and yolk content of the Eggs. In the case of the TOBEC measurements it was established that the dry matter and fat content of the Eggs could be measured with medium accuracy (R≤=0.472 and R≤=0.486, respectively), when the electrical conductivity (E-value) and the weight of the Eggs a re used as independent variables in the linear regression model. In the second experiment it was o bserved that the separation of Egg yolk and albumen is not possible based on the X-ray density values of the pixels (CT picture elements) because of the overlapping values of yolk and albumen. The determination of the surface of Egg yolk on the CT pictures gave fairly good results, but this type of the evaluation is very time consuming. Therefor e further development of the new Egg-separation and s egmentation software is needed, which can be used to determine the whole volume of the yolk, alb umen and shell automatically.
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Effect of Egg Composition on hatchability and on growth and slaughter characteristics of meat-type chicks.
British poultry science, 2010Co-Authors: Gabor Milisits, E. Kovács, O. Pocze, J. Ujvari, Zs Taraszenkó, Gabriella Jekkel, L. Locsmándi, Gy. Bázár, András Szabó, Róbert RomváriAbstract:1. Using the so-called TOBEC (Total Body Electrical Conductivity) method, which allows the determination of Egg Composition in vivo, correlations between Egg Composition, hatchability and hatched chicks’ development were studied. 2. A total of 1500 hen Eggs (Ross-308) were measured by TOBEC, and Eggs with extremely high (10%, n = 150), extremely low (10%, n = 150) and average (10%, n = 150) electrical conductivity values were chosen for further investigation. 3. During the incubation period, it was observed that Eggs with high electrical conductivity had a significantly higher mortality than Eggs with low electrical conductivity. 4. It was observed that both the increase in electrical conductivity at the same Egg weight, and the increase in Egg weight at the same electrical conductivity resulted in an increase in the hatching weight. 5. It was found that the dry matter, protein and fat content of the chicks hatched from Eggs with low electrical conductivity was higher at hatching than that of the chicks h...
Anne E. Storey - One of the best experts on this subject based on the ideXlab platform.
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Egg Composition IN RELATION TO FEMALE AGE AND RELAYING: CONSTRAINTS ON Egg PRODUCTION IN THICK-BILLED MURRES
2016Co-Authors: Uria Lomvia, J. Mark Hipfner, Anthony J. Gaston, Gene R. Herzberg, John T. Brosnan, Anne E. StoreyAbstract:-There is growing awareness that costs associated with Egg production play a significant role in shaping avian life histories. The life-history strategy of the Thick-billed Murre (Uria lomvia), a colonial, cliff-breeding seabird of Arctic waters, is characterized by a high annual adult survival rate, deferred breeding, and laying of a single-Egg clutch. The single-Egg clutch is a widespread phenomenon among seabirds and is generally thought to reflect demands of chick provisioning, rather than Egg production. We compared Composition of Eggs laid by Thick-billed Murres most likely to be physiologically constrained in their capacity to produce Eggs (young females with no prior experience, and females forming replacement Eggs) to that of first Eggs laid by early laying females (typically older, more experienced members of the population). Young, inexperienced females laid 4-18 days past the populationwide median laying date, and their Eggs averaged 13% lighter in mass than those laid by early layers. Compared to early laid Eggs, shell mass on young females' Eggs was similar to that predicted from Egg mass, but their Eggs had a lower yolk-to-albumen ratio. There was little difference between the two groups in relative protein content of albumen, relative protein or lipid content of yolk, or amino acid makeup of protein in yolk or albumen. Replacement Eggs averaged 6% lighter in mass than first Eggs laid by the same females earlier that season. As with young females' Eggs, replacement Eggs had shells similar in mass to that predicted from Egg mass, but lower yolk-to-albumen ratios, when compared to early laid Eggs. Both protein and lipid concentrations in yolk were similar in first and replacement Eggs, but replacements were deficient in albumen protein. Amino acid makeup of protein in yolk and albumen was similar in the two groups. Those results suggest that any limitations on Egg production acting on young, inexperienced females are manifested in delayed laying and reductions in overall Egg mass and proportional yolk content, but not in variation in biochemical Composition of their Eggs. Limitations on females forming replacement Eggs are manifested not only in reduced Egg mass and yolk content (as with young females), but also in changes in the biochemical Composition of Eggs; in particular, evidence suggests that relaying females may face a deficit of endogenous protein. The existence of such limitations suggests that demands of Egg production can be significant even in a species that lays a single-Egg clutch. Received 3 January 2002, accepted 3 February 2003. REsuME.-Il y a une prise de conscience grandissante concernant les cofits associes a la production d'ceufs qui jouent un r6le significatif en faconnant les traits d'histoire de vie chez les oiseaux. Chez le Guillemot de Briinnich (Uria lomvia), un oiseau des mers Arctiques, colonial et nichant sur les falaises, la strat6gie en matiere de traits d'histoire de vie se caracterise par un taux de survie annuel tres 6leve chez l'adulte, une reproduction pouvant etre differee, et la ponte d'un seul ceuf. Ce type de couv6e est un phenomene repandu chez les oiseaux de mer. Ce 5Present address: Canadian Wildlife Service, Pacific Wildlife Research Centre, RR#1 5421 Robertson Road, Delta, British Columbia V4K 3N2, Canada. E-mail: mark.hipfner@ec.gc.ca
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Egg Composition in Relation to Female Age and Relaying: Constraints on Egg Production in Thick-Billed Murres (Uria Lomvia)
The Auk, 2003Co-Authors: J. Mark Hipfner, Anthony J. Gaston, Gene R. Herzberg, John T. Brosnan, Anne E. StoreyAbstract:Abstract There is growing awareness that costs associated with Egg production play a significant role in shaping avian life histories. The life-history strategy of the Thick-billed Murre (Uria lomvia), a colonial, cliff-breeding seabird of Arctic waters, is characterized by a high annual adult survival rate, deferred breeding, and laying of a single-Egg clutch. The single-Egg clutch is a widespread phenomenon among seabirds and is generally thought to reflect demands of chick provisioning, rather than Egg production. We compared Composition of Eggs laid by Thick-billed Murres most likely to be physiologically constrained in their capacity to produce Eggs (young females with no prior experience, and females forming replacement Eggs) to that of first Eggs laid by early laying females (typically older, more experienced members of the population). Young, inexperienced females laid 4–18 days past the populationwide median laying date, and their Eggs averaged 13% lighter in mass than those laid by early layers. Compared to early laid Eggs, shell mass on young females’ Eggs was similar to that predicted from Egg mass, but their Eggs had a lower yolk-to-albumen ratio. There was little difference between the two groups in relative protein content of albumen, relative protein or lipid content of yolk, or amino acid makeup of protein in yolk or albumen. Replacement Eggs averaged 6% lighter in mass than first Eggs laid by the same females earlier that season. As with young females’ Eggs, replacement Eggs had shells similar in mass to that predicted from Egg mass, but lower yolk-to-albumen ratios, when compared to early laid Eggs. Both protein and lipid concentrations in yolk were similar in first and replacement Eggs, but replacements were deficient in albumen protein. Amino acid makeup of protein in yolk and albumen was similar in the two groups. Those results suggest that any limitations on Egg production acting on young, inexperienced females are manifested in delayed laying and reductions in overall Egg mass and proportional yolk content, but not in variation in biochemical Composition of their Eggs. Limitations on females forming replacement Eggs are manifested not only in reduced Egg mass and yolk content (as with young females), but also in changes in the biochemical Composition of Eggs; in particular, evidence suggests that relaying females may face a deficit of endogenous protein. The existence of such limitations suggests that demands of Egg production can be significant even in a species that lays a single-Egg clutch.
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Egg Composition IN RELATION TO FEMALE AGE AND RELAYING: CONSTRAINTS ON Egg PRODUCTION IN THICK-BILLED MURRES (URIA LOMVIA)
The Auk, 2003Co-Authors: J. Mark Hipfner, Anthony J. Gaston, Gene R. Herzberg, John T. Brosnan, Anne E. StoreyAbstract:Abstract There is growing awareness that costs associated with Egg production play a significant role in shaping avian life histories. The life-history strategy of the Thick-billed Murre (Uria lomvia), a colonial, cliff-breeding seabird of Arctic waters, is characterized by a high annual adult survival rate, deferred breeding, and laying of a single-Egg clutch. The single-Egg clutch is a widespread phenomenon among seabirds and is generally thought to reflect demands of chick provisioning, rather than Egg production. We compared Composition of Eggs laid by Thick-billed Murres most likely to be physiologically constrained in their capacity to produce Eggs (young females with no prior experience, and females forming replacement Eggs) to that of first Eggs laid by early laying females (typically older, more experienced members of the population). Young, inexperienced females laid 4–18 days past the populationwide median laying date, and their Eggs averaged 13% lighter in mass than those laid by early layers....
Tony D. Williams - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of a non‐destructive method for determining Egg Composition using total body electrical conductivity (TOBEC) measurements
Journal of Zoology, 1997Co-Authors: Tony D. Williams, Pat Monaghan, P. I. Mitchell, Ian Scott, D. G. Houston, S. Ramsey, K. EnsorAbstract:It is widely assumed that there is a positive relationship between Egg quality (or Egg size) and offspring fitness. However, obtaining unequivocal data in support of this hypothesis has been hampered by the lack of any method for non-destructive determination of Egg Composition, preventing a direct analysis of Egg quality and subsequent chick growth and survival in the same Egg(s). In this paper, we describe the application of a rapid, non-destructive technique using measurement of total body electrical conductivity (TOBEC) for determination of Egg Composition in intact Eggs. The TOBEC index was positively and highly correlated with Egg lean mass and with the mass of some Egg components (albumen and water content). Values for predicted lean mass, based on the regression equation for lean mass against TOBEC index, were within ±6% of actual lean mass. Egg lipid mass was most accurately predicted (±15%) using a multiple regression model, with fresh Egg mass and TOBEC index included as independent variables. Egg temperature, and the position of the Egg in the sampling chamber, markedly affected the TOBEC index obtained.
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intraspecific variation in Egg size and Egg Composition in birds effects on offspring fitness
Biological Reviews, 1994Co-Authors: Tony D. WilliamsAbstract:: 1. There is little unequivocal evidence to date in support of a positive relationship between Egg size and offspring fitness in birds. Although 40 studies (of 34 species) have considered the effect of variation in Egg size on chick growth and/or survival up to fledgling only 12 studies have controlled for other characters potentially correlated both with Egg size and offspring fitness. Of these only two have reported a significant residual effect of Egg size on chick growth (in the roseate tern and European blackbird) and three a residual effect on chick survival (all in seabirds: common tern, lesser black-backed gull and kittiwake). 2. More consistent evidence exists, though from fewer studies, for a positive relationship between Egg size and offspring fitness early in the chick-rearing period; chick growth and chick survival being dependent on Egg size in 8 of 10 studies and 4 of 5 studies respectively. It is suggested that the most important effect of variation in Egg size might be in determining the probability of offspring survival in the first few days after hatching. 3. Egg size explains on average 66% of the variation in chick mass at hatching (n = 35 studies) but only 30% of the variation in chick body size (n = 18). When effects of hatching body size are controlled for chick mass remains significantly correlated with Egg size, though the reverse is not true. This supports the hypothesis that large Eggs give rise to heavier chicks at hatching, i.e., chicks with more nutrient (yolk) reserves, rather than structurally larger chicks. 4. Egg Composition increased isometrically with increasing Egg size in about half the studies so far reported (n equals approximately 20). However, in seabirds, and some passerines, larger Eggs contain disproportionately more albumen, whilst in some waterfowl percentage yolk content increases with increasing Egg size. Changes in albumen content largely reflect variation in the water content of Eggs, but changes in yolk content involve variation in lipid content, and therefore in Egg 'quality.' The adaptive significance of variation in Egg Composition is considered; females may adjust Egg Composition facultatively to maximise the benefits to their offspring of increased reproductive investment. 5. Considerations for future research are discussed with particular emphasis on experimental studies and the application of new techniques.
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INTRASPECIFIC VARIATION IN Egg SIZE AND Egg Composition IN BIRDS: EFFECTS ON OFFSPRING FITNESS
Biological reviews of the Cambridge Philosophical Society, 1994Co-Authors: Tony D. WilliamsAbstract:1. There is little unequivocal evidence to date in support of a positive relationship between Egg size and offspring fitness in birds. Although 40 studies (of 34 species) have considered the effect of variation in Egg size on chick growth and/or survival up to fledgling only 12 studies have controlled for other characters potentially correlated both with Egg size and offspring fitness. Of these only two have reported a significant residual effect of Egg size on chick growth (in the roseate tern and European blackbird) and three a residual effect on chick survival (all in seabirds: common tern, lesser black-backed gull and kittiwake). 2. More consistent evidence exists, though from fewer studies, for a positive relationship between Egg size and offspring fitness early in the chick-rearing period; chick growth and chick survival being dependent on Egg size in 8 of 10 studies and 4 of 5 studies respectively. It is suggested that the most important effect of variation in Egg size might be in determining the probability of offspring survival in the first few days after hatching. 3. Egg size explains on average 66% of the variation in chick mass at hatching (n = 35 studies) but only 30% of the variation in chick body size (n = 18). When effects of hatching body size are controlled for chick mass remains significantly correlated with Egg size, though the reverse is not true. This supports the hypothesis that large Eggs give rise to heavier chicks at hatching, i.e., chicks with more nutrient (yolk) reserves, rather than structurally larger chicks. 4. Egg Composition increased isometrically with increasing Egg size in about half the studies so far reported (n equals approximately 20). However, in seabirds, and some passerines, larger Eggs contain disproportionately more albumen, whilst in some waterfowl percentage yolk content increases with increasing Egg size. Changes in albumen content largely reflect variation in the water content of Eggs, but changes in yolk content involve variation in lipid content, and therefore in Egg 'quality.' The adaptive significance of variation in Egg Composition is considered; females may adjust Egg Composition facultatively to maximise the benefits to their offspring of increased reproductive investment. 5. Considerations for future research are discussed with particular emphasis on experimental studies and the application of new techniques.
Nicola Saino - One of the best experts on this subject based on the ideXlab platform.
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Egg Testosterone Differentially Affects Telomere Length in Somatic Tissues of Yellow-LEgged Gull Embryos.
Physiological and biochemical zoology : PBZ, 2019Co-Authors: Marco Parolini, Cristina Daniela Possenti, Manuela Caprioli, Diego Rubolini, Andrea Romano, Nicola SainoAbstract:AbstractMaternal decisions on Egg Composition have major consequences for offspring. Maternal Egg androgens have diverse, often contrasting, effects depending on offspring trait and life stage, sug...
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maternal effects mediated by Egg quality in the yellow lEgged gull larus michahellis in relation to laying order and embryo sex
Frontiers in Zoology, 2011Co-Authors: Diego Rubolini, Manuela Caprioli, Maria Romano, Kristen J Navara, Filiz Karadas, Roberto Ambrosini, Nicola SainoAbstract:Background Maternal effects mediated by Egg size and quality may profoundly affect offspring development and performance, and mothers may adjust Egg traits according to environmental or social influences. In avian species, context-dependency of maternal effects may result in variation in Egg Composition, as well as in differential patterns of covariation among selected Egg components, according to, for example, position in the laying sequence or offspring sex. We investigated variation in major classes of Egg yolk components (carotenoids, vitamins and steroid hormones) in relation to Egg size, position in the laying sequence and embryo sex in clutches of the Yellow-lEgged Gull (Larus michahellis). We also investigated their covariation, to highlight mutual adjustments, maternal constraints or trade-offs in Egg allocation.
Zoltán Sütő - One of the best experts on this subject based on the ideXlab platform.
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Effect of starting body fat content and genotype of laying hens on the changes in their live weight, body fat content, Egg production and Egg Composition during the first Egg-laying period.
British poultry science, 2015Co-Authors: Gabor Milisits, J. Ujvari, Tamás Donkó, Eszter Szentirmai, Z. Budai, S. Áprily, G. Bajzik, Zoltán SütőAbstract:A total 120 laying hens (60 TETRA BLANCA white Egg layers and 60 TETRA SL brown Egg layers) were selected from 250 TETRA BLANCA and 250 TETRA SL pullets based on their predicted body fat content by means of computed tomography (CT) at 16 weeks of age. Three groups of pullets were chosen for the investigation with the highest (n = 20), lowest (n = 20) and average (n = 20) body fat content. Changes in the live weight, body fat content, Egg production and Egg Composition of the chosen animals were recorded at 32, 52 and 72 weeks of age. Based on the results, it was established that differences in starting body fat content of the hens remained the same during the experimental period. The differences between the two extreme groups were statistically significant at each age. The starting body fat content of the hens affected the rate of Egg production, i.e. hens with high starting body fat content produced 11-14 Eggs fewer than the hens with a low or average body fat content but had no effect on the Composition of the Eggs. Genotype affected almost all of the examined traits: TETRA BLANCA hens had lower live weight and higher body fat content during the experimental period and produced fewer Eggs with lower albumen and higher yolk, dry matter and crude fat content than the TETRA SL hens.
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Comparison of changes in production and Egg Composition in relation to in vivo estimates of body weight and Composition of brown and white Egg layers during the first Egg-laying period
British poultry science, 2013Co-Authors: Eszter Szentirmai, Gabor Milisits, J. Ujvari, Tamás Donkó, Imre Repa, Z. Budai, T. Fülöp, Zoltán SütőAbstract:1. The aim of this study was to compare the changes in the production and in the body and Egg Composition of 45 TETRA SL brown Egg layers and 45 TETRA BLANCA white Egg layers during the first Egg-laying period.2. Changes in the body Composition of the hens were followed in vivo by means of computed tomography (CT) four-weekly, between 20 and 72 weeks of age. The measurements covered the whole body of the hens using overlapping 10 mm slice thicknesses on a Siemens Somatom Emotion 6 multislice CT scanner.3. The yolk, albumen and shell ratio of the Eggs, produced on the days of the CT measurements by the hens, were determined and their Composition was analysed chemically.4. The body fat content of the hens increased continuously until 44 weeks of age and plateaued thereafter in both genotypes. However, the body fat content of the white Egg layers was always higher than that of the brown Egg layers.5. The yolk ratio and the dry matter and crude fat content of the Eggs of white Egg layers were higher than the ...
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A tojásösszetétel, a keltethetőség, valamint a kikelő madarak fejlődése és termelése közötti összefüggések in vivo vizsgálata komputer tomográffal kettőshasznosítású tyúk genotípusokban = In vivo examination of the correlations between hen's Egg comp
2011Co-Authors: Gabor Milisits, Tamás Donkó, Zoltán Sütő, Antonella Dalle Zotte, András SzabóAbstract:A kutatasi program kereteben kidolgoztuk a tyuktojasok CT vizsgalatanak metodikajat. Meghataroztuk a legjobban ertekelhető felvetelek elkeszitesehez szukseges technikai parametereket es az egyidejűleg vizsgalhato tojasok szamat. A tojasok sargaja aranyanak meghatarozasahoz egy uj szoftvert fejlesztettunk, ami lehetőve tette a keresztmetszeti kepek gyors es automatikus ertekeleset. Megallapitottuk, hogy a kisebb sargaja, azaz nagyobb feherje arannyal rendelkező tojasokbol nagyobb sulyu csibek kelnek mindket ivarban. A kakasok eseteben a nagyobb feherje aranyu tojasokbol kelt madarak a testsulybeli folenyuket a hizlalas vegeig megőriztek, mig a jercek kelesi sulyaban megfigyelt kulonbsegeket a hizlalas vegen mar nem lehetett kimutatni. A keltetőtojasok sargaja aranya szignifikans hatassal volt viszont a jercek testzsirtartalmanak neveles alatti alakulasara, ami kihatassal volt a kesőbbi termelesukre. A kutatas soran megallapitottuk, hogy a tyuktojasok osszetetele a CT hasznalataval pontosabban becsulhető, mint a korabban alkalmazott TOBEC modszerrel. A tojasok osszetetele szignifikans hatassal van a csibek kelesi sulyanak es testosszetetelenek alakulasara, ami kihatassal van a kesőbbi fejlődesukre es ezen keresztul a termelesukre. Mindezek alapjan indokoltnak tűnik a tojasosszetetel in vivo meghatarozasanak tovabbi pontositasa, a tojasosszetetel, a keltethetőseg, valamint a kikelő madarak fejlődese es termelese kozotti osszefuggesek tovabbi tisztazasa erdekeben. | In the frame of this research project the methodology of CT examination of hen’s Eggs was developed. The optimal technical parameters and the number of simultaneously scanable Eggs were determined in order to obtain the best quality CT images for the evaluation. For the fast and automatic determination of yolk ratio a new software was developed. By separating Eggs with different predicted yolk ratios it was established that chicks hatched from Eggs with low yolk – high albumen – content had higher liveweight at hatching in both sexes. This higher liveweight was also observed at the end of the rearing period in the case of the cocks, but it was not observable in the case of the pullets. However, the yolk content of the Eggs had a significant effect on the body fat content of the pullets, which affected the latter production of these birds. During this research work it was also established that the predictability of the Composition of hen’s Eggs is more accurate by means of the CT than it was formerly by means of the TOBEC method. The Composition of the Eggs has a significant effect on the liveweight and body Composition of the chicks at hatching, which has an effect on their latter development and production. Therefore, based on these results it seems to be necessary to improve the accuracy of the in vivo prediction of Egg’s Composition in order to clarify the correlations between Egg Composition, hatchability and hatched bird’s development and production more precisely.
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Possibilities and Deliminations In Vivo Determination of Egg Composition
Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Animal Science and Biotechnologies, 2010Co-Authors: Gabor Milisits, Tamás Donkó, Miklós Emri, Gábor Opposits, Attila Orbán, Zoltán Sütő, Imre RepaAbstract:The aim of these experiments was to examine the applicability of two different methods (TOBEC and CT) for the in vivo prediction of Egg Composition. In the first experiment the electrical conductivity of 46 hen's Eggs was measur ed by means of the TOBEC (Total Body Electrical Conductivity) method and correlations were calculat ed between the measured values and different Egg components (dry matter, protein, fat). In the secon d experiment 120 hen's Eggs were scanned by CT (computer tomography), in order to develop the CT measurement protocol and to determine correlations between the information content of the CT images and yolk content of the Eggs. In the case of the TOBEC measurements it was established that the dry matter and fat content of the Eggs could be measured with medium accuracy (R≤=0.472 and R≤=0.486, respectively), when the electrical conductivity (E-value) and the weight of the Eggs a re used as independent variables in the linear regression model. In the second experiment it was o bserved that the separation of Egg yolk and albumen is not possible based on the X-ray density values of the pixels (CT picture elements) because of the overlapping values of yolk and albumen. The determination of the surface of Egg yolk on the CT pictures gave fairly good results, but this type of the evaluation is very time consuming. Therefor e further development of the new Egg-separation and s egmentation software is needed, which can be used to determine the whole volume of the yolk, alb umen and shell automatically.
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Comparison of the slaughter characteristics of meat-type chicks hatched from Eggs with different Composition
Italian Journal of Animal Science, 2009Co-Authors: Gabor Milisits, E. Kovács, J. Ujvari, Gabriella Jekkel, Olga Pőcze, Zoltán SütőAbstract:Using the so-called TOBEC (Total Body Electrical Conductivity) method for the in vivo determination of Egg Composition, the effect of Egg Composition on the slaughter characteristics of hatched chicks was examined in the ROSS-308 meat-type genotype. Chicks hatched from Eggs with low, average and high electrical conductivity were slaughtered at 42 days of age. It was found that the weight of all of the examined traits showed highest values in the case of chicks hatched from Eggs with low electrical conductivity, while the lowest values could be observed in the case of chicks hatched from Eggs with high electrical conductivity. Similar tendencies were observed also in the case of the ratio of the examined slaughter traits to the slaughter weight, but in this case the differences were not statistically proven (P>0.05).