Abstract
Maiden and mature Merino ewes were subjected to continuous heat stress for the first 20 days of gestation.In both control and hotroom groups the age of the ewes had no apparent influence on the rate of embryonic mortality experienced, although heat stress gave rise to a highly significant (p < 0.001) increase in the overall embryonic mortality rate.
Zusammenfassung
Junge und erwachsene Merino Schafe wurden während der ersten zwanzig Tage der Trächtigkeit einer andauernden Hitzebelastung ausgesetzt.Sowohl in der Kontroll- wie in der belasteten Gruppe hatte das Alter der Schafe keinen nachweisbaren Einfluss auf die Absterberate der Embryos, obwohl die Hitzebelastung die allgemeine Absterberate von Embryos mit grosser Signifikanze (p < 0,001)anwachsen liess.
Resume
Des brebis et adultes de la race "Mérinos" furent exposées à une contrainte de chaleur constante durant les 20 premiers jours de leur gestation. Il n'a pas été possible de prouver que l'âge des brebis ait une influence sur le taux de mortalité des embryons ni dans le groupe des animaux exposés au chaud, ni dans celui servant au contrôle. La contrainte thermique a cependant fait augmenter de façon très significative (p < 0,001) le taux de mortalité des embryons.
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References
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Thwaites, C.J. The influence of age of ewe on embryo mortality under heat stress conditions. Int J Biometeorol 12, 29–33 (1968). https://doi.org/10.1007/BF01552975
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DOI: https://doi.org/10.1007/BF01552975