Rosa Angélica Sanmiguel; Anna Dedousi; Juan David López; Daniel Andrey Sierra; Evangelia Nikolaus Sossidou
Volume 13, Issue 4 , December 2022, , Pages 461-467
Abstract
This study aimed to determine the effects of in-feed inclusion of humic substances (HS) and/or calcium carbonate (CaCO3) on the performance and welfare of laying hens. A total number of 144 Hy-Line Brown laying hens (55 weeks old) were randomly assigned to four treatments, T1–T4 (36 birds per treatment). ...
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This study aimed to determine the effects of in-feed inclusion of humic substances (HS) and/or calcium carbonate (CaCO3) on the performance and welfare of laying hens. A total number of 144 Hy-Line Brown laying hens (55 weeks old) were randomly assigned to four treatments, T1–T4 (36 birds per treatment). T1 hens were fed on a control diet without HS or CaCO3, T2 hens were fed on the control diet + 2.00 g per bird per day CaCO3, T3 hens were fed on the control diet + 0.20% HS and T4 hens were fed on the control diet + 0.20% HS + 2.00 g/bird/day CaCO3. The experiment started after 15 days of adaptation and lasted 8 weeks. The parameters evaluated were percentage of hen-day egg production, food consumption, mortality, egg quality parameters and heart rate variability (welfare indicator). Hens in the T3 group showed a significantly lower feed intake than those in the other three groups, however, significantly higher daily egg production was recorded in groups T3 and T4 compared to T1 and T2. Eggshell quality characteristics were significantly improved by HS supplementation and eggs laid by hens in groups T1, and T4 presented paler yolk and shell color than those in the other groups. In conclusion, these results indicated that in-feed inclusion of HS had a beneficial effect on laying hens’ productive performance including egg production and eggshells quality.
Panagiotis Dimitrios Katsoulos; Labrini Vasileiou Athanasiou; Anna Dedousi; Zoe Polizopoulou
Volume 13, Issue 4 , December 2022, , Pages 475-480
Abstract
Despite being important, there are no equations for prediction of ionized calcium (iCa) in sheep and cattle. The objectives of this study were i) to create equations for the calculation of serum iCa concentration based on the serum concentrations of total calcium (tCa), albumin (Alb) and total proteins ...
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Despite being important, there are no equations for prediction of ionized calcium (iCa) in sheep and cattle. The objectives of this study were i) to create equations for the calculation of serum iCa concentration based on the serum concentrations of total calcium (tCa), albumin (Alb) and total proteins (TP) and ii) to investigate whether predicted serum iCa values are beneficial in clinical practice. Serum samples from 30 sheep and 30 dairy cattle were used. Serum tCa was determined colorimetrically, while serum iCa was determined with an ion selective electrode method. Serum Alb and TP concentration were determined using bromo-cresol green and biuret methods, respectively. Ionized calcium was also calculated based on serum tCa, using regression analysis, and with two equations based on Alb and TP concentration. Bland–Altman plots were plotted to evaluate the agreement between measured and predicted iCa; Passing and Bablok (P - B) regression analysis was used to assess their agreement. The initial equations were corrected using the P - B generated equation and Bland – Altman plots were run to evaluate the level of agreement between measured and predicted iCa using the final equations. Six equations were finally created for cattle and 6 for sheep. The total bias exceeded 10.00% in all of them indicating that they are clinically unacceptable for iCa prediction especially when the predicted result is very close to the cut-off point of < 1.00 mmol L-1. So, it could be suggested that, when necessary, iCa concentration should be directly determined.
Anna Dedousi; Mirjana Đukić Stojčić; Evangelia Sossidou
Volume 11, Issue 4 , December 2020, , Pages 299-304
Abstract
The aim of this study was to investigate whether keel bone damage is prevalent in laying hens in Greece. The study was conducted in three industrial farms using different housing systems: (a) enriched cages, (b) floor system, and (c) free-range system. One hundred hens per housing system, randomly selected, ...
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The aim of this study was to investigate whether keel bone damage is prevalent in laying hens in Greece. The study was conducted in three industrial farms using different housing systems: (a) enriched cages, (b) floor system, and (c) free-range system. One hundred hens per housing system, randomly selected, were evaluated for keel bone damages with the method of palpation. Complementarily, thirty eggs from each farm were selected for the measurement of egg weight, shape index, shell cleanness, shell color, shell breaking force, shell thickness, shell weight, egg yolk color, albumen height, and Haugh unit. The presence of keel bone damage was evident in all housing systems with the significantly highest occurrence being observed in the free-range system (50.00%), followed by enriched cages (24.00%) and floor system (7.00%). Eggs from all three systems had significant differences in all estimated egg quality parameters apart from shell color and Haugh unit.