Resumo
The effects of three egg-turning regimes during the pre-incubation storage period on egg weight loss, hatchability, embryonic mortality, chick weight at hatching and incubation length of red-legged partridge (Alectoris rufa) compared with unturned eggs were investigated. Two hundred eggs were allocated to four 50-egg batches stored at 15ºC and 80% RH that being turned one, four and 24 times a day or remaining unturned, respectively. Eggs were incubated at 37.8ºC and 55% RH during the first 21 days and at 37.5ºC and 75% RH until hatching. Fertility was 70.5% and a good hatchability performance was obtained, characterised by 81.6% hatchability of fertile eggs, and weight losses of 0.78% during storage and of 10.04% during the first 21 days of incubation, 13.6 ±0.1 g hatchling weight, and incubation length of 23.45 ± 0.07 days (mean ± SEM). Hatchability, embryonic mortality developmental stage, egg weight loss during storage and incubation, hatchling weight and length of the incubation period were not affected by the turning frequency or the absence of turning during storage. Higher hatching synchrony was observed for eggs turned four times a day compared with unturned eggs and eggs turned once a day. In conclusion, turning red-legged partridge eggs during medium-term storage periods does not improve egg viability compared with unturned eggs.(AU)
Assuntos
Animais , Galliformes/embriologia , Incubadoras/veterinária , Ovos/análiseResumo
The effects of three egg-turning regimes during the pre-incubation storage period on egg weight loss, hatchability, embryonic mortality, chick weight at hatching and incubation length of red-legged partridge (Alectoris rufa) compared with unturned eggs were investigated. Two hundred eggs were allocated to four 50-egg batches stored at 15ºC and 80% RH that being turned one, four and 24 times a day or remaining unturned, respectively. Eggs were incubated at 37.8ºC and 55% RH during the first 21 days and at 37.5ºC and 75% RH until hatching. Fertility was 70.5% and a good hatchability performance was obtained, characterised by 81.6% hatchability of fertile eggs, and weight losses of 0.78% during storage and of 10.04% during the first 21 days of incubation, 13.6 ±0.1 g hatchling weight, and incubation length of 23.45 ± 0.07 days (mean ± SEM). Hatchability, embryonic mortality developmental stage, egg weight loss during storage and incubation, hatchling weight and length of the incubation period were not affected by the turning frequency or the absence of turning during storage. Higher hatching synchrony was observed for eggs turned four times a day compared with unturned eggs and eggs turned once a day. In conclusion, turning red-legged partridge eggs during medium-term storage periods does not improve egg viability compared with unturned eggs.
Assuntos
Animais , Galliformes/embriologia , Incubadoras/veterinária , Ovos/análiseResumo
This study aimed at investigating the effects of three incubation temperatures during the hatching period on egg weight loss, hatchability, chick weight at hatching and length of the incubation period of red-legged partridge (Alectoris rufa) under artificial incubation. One hundred and fifty eggs obtained from a red-legged partridge game farm were randomly allocated to three batches of 50 eggs each. Eggs were incubated at 37.8ºC during the first 20 days, and subsequently at 37.0, 37.4 or 37.8ºC until hatching. Fertility was 74.7% and a good hatching performance was obtained, characterized by 85.7% hatchability, 9.1% egg weight loss after 20 days of incubation, 13.8±0.1 g chick weight at hatching, and 23.2±0.1 days incubation length. Hatchability, egg weight loss after 20 days of incubation, and length of the incubation period were not affected by incubation temperature during the hatching period. However, hatching synchrony improved when the incubation temperature was increased from 37.0 to 37.8°C (p 0.05). Thus, hatching distribution became very leptokurtic and very positively skewed with the increase in incubation temperature during the hatching phase. In conclusion, higher hatching synchrony can be achieved in A. rufa when setting temperatures within the range 37.0 to 37.8ºC to incubate eggs during the hatching period. Consequently, incubation temperature management during the hatching phase may have a direct impact on hatching synchrony and hatchling management.
Assuntos
Animais , Galliformes/crescimento & desenvolvimento , Galliformes/embriologia , Óvulo/fisiologiaResumo
This study aimed at investigating the effects of three incubation temperatures during the hatching period on egg weight loss, hatchability, chick weight at hatching and length of the incubation period of red-legged partridge (Alectoris rufa) under artificial incubation. One hundred and fifty eggs obtained from a red-legged partridge game farm were randomly allocated to three batches of 50 eggs each. Eggs were incubated at 37.8ºC during the first 20 days, and subsequently at 37.0, 37.4 or 37.8ºC until hatching. Fertility was 74.7% and a good hatching performance was obtained, characterized by 85.7% hatchability, 9.1% egg weight loss after 20 days of incubation, 13.8±0.1 g chick weight at hatching, and 23.2±0.1 days incubation length. Hatchability, egg weight loss after 20 days of incubation, and length of the incubation period were not affected by incubation temperature during the hatching period. However, hatching synchrony improved when the incubation temperature was increased from 37.0 to 37.8°C (p 0.05). Thus, hatching distribution became very leptokurtic and very positively skewed with the increase in incubation temperature during the hatching phase. In conclusion, higher hatching synchrony can be achieved in A. rufa when setting temperatures within the range 37.0 to 37.8ºC to incubate eggs during the hatching period. Consequently, incubation temperature management during the hatching phase may have a direct impact on hatching synchrony and hatchling management.(AU)