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Vliv podmínek inkubace na parametry užitkovosti brojlerových kuřat
Opavská, Tereza
This thesis deals with the effect of increased temperature during first 36 hours of incubation on embryonic development, hatchability, day-old chicks quality and subsequently on their growth. The chickens of the control group were hatched at a standard temperature of 100,8 °F and the experimental group had increased temperature of 102,5 °F for the first 36 hours of incubation. The growth experiment was performer on 423 roosters of the Ross 308 hybrid combination from hatch to day 31 of age. The day-old chicks from the control group weighed statistically significantly (P<0,05) more than the experimental group. However, at 10 and 17 day of age, no statistically significant (P>0,05) difference was found between the groups. At the 24 and 31 day of age, the average weight of control group was again statistically significantly (P<0,05) higher than the weight of the experimental group. There was no significant difference in the hatchability of fertilized eggs, which was 92,2 % in the control group and 90,4 % in the experimental group. However, the mean embryonic mortality was 1,76 % and the late mortality 2,47 % in the control group, while the mean mortality was 0,71 % and the late 4,17 % in the experimental group, these differences were statistically significant (P<0,05). The difference in the average weight of the yolk sacs, in the proportion of yolk sacs from live weight and in the activity of T3 (thyroid hormone triiodothyronine), which reached 1,38 nmol/l in day-old chicks of the control group and 1,35 nmol/l in the experimental group was not statistically significant (P>0,05). No statistically significant (P>0,05) difference was found in feed conversion. Based on the results, the increased incubation temperature (102,5 ° F) has had a negative impact on the growth of broiler chickens.
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Effect of incubation temperature on phenotype in mallard
Cílková, Martina ; Hořák, David (advisor) ; Krist, Miloš (referee)
The influence of incubation temperature on bird neonate phenotype is widely studied. In waterfowl (Anatidae), maternal effect can be divided to two main parts: clutch formation and its incubation. Therefore, waterfowl are a good model for this type of study. The egg temperature can strongly influence embryo development and survival of the hatchlings. The goal of this work was to examine the effect of incubation temperature on hatchability, incubation length, sex ratio and phenotype of European Mallard ducklings immediately after hatching. Eggs were randomly placed in one of six incubation temperatures, which ranged from 35 to 39 řC. This range corresponds with temperature range in natural mallard nests in the Czech Republic. Eggs were then artificially incubated. Newborn hatchlings were weighted and their structural size was measured, then they were killed. Some hatchlings from incubation temperatures 35.5, 36 and 37 řC were used to examine residual yolk sac mass and basic chemical composition of the yolk-free body. Hatchability was markedly lower in both extreme temperatures (35 and 39 řC). Incubation length significantly decreased with increasing incubation temperature. I failed to prove the influence of incubation temperature on hatchling body mass, but I found temperature-dependent changes of...
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Effect of incubation temperature on phenotype in mallard
Cílková, Martina ; Hořák, David (advisor) ; Krist, Miloš (referee)
The influence of incubation temperature on bird neonate phenotype is widely studied. In waterfowl (Anatidae), maternal effect can be divided to two main parts: clutch formation and its incubation. Therefore, waterfowl are a good model for this type of study. The egg temperature can strongly influence embryo development and survival of the hatchlings. The goal of this work was to examine the effect of incubation temperature on hatchability, incubation length, sex ratio and phenotype of European Mallard ducklings immediately after hatching. Eggs were randomly placed in one of six incubation temperatures, which ranged from 35 to 39 řC. This range corresponds with temperature range in natural mallard nests in the Czech Republic. Eggs were then artificially incubated. Newborn hatchlings were weighted and their structural size was measured, then they were killed. Some hatchlings from incubation temperatures 35.5, 36 and 37 řC were used to examine residual yolk sac mass and basic chemical composition of the yolk-free body. Hatchability was markedly lower in both extreme temperatures (35 and 39 řC). Incubation length significantly decreased with increasing incubation temperature. I failed to prove the influence of incubation temperature on hatchling body mass, but I found temperature-dependent changes of...
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