Abstract
BACKGROUND: The effect of heat stress on physiologicalparameters has been well documented. However, there arereports of a genetic based heat tolerance in some sheep breeds.OBJECTIVES: The aim of the present study was to monitor thephysiological responses of an Iranian fat-tailed breed againstheat stress and an acute stress insult. METHODS:Atotal numberof 15 fall-born ram lambs were selected and subjected to directsummer solar radiation throughout the day (May 2009 toFebruary 2010). Ten lambs were semi-castrated in October to seethe physiologic response of animals to an acute stress. Thegeneral parameter as well as blood chemistry and cortisol wereanalyzed during the study. RESULTS: The results showed that allphysiologic parameters had significant changes; however, theirvalues were in normal range. The fact that the animals in thepresent study experienced their first exposure of heat stress anda significant increase in serum cortisol concentration in semicastratedlambs in October, compared to the respected values inthe hottest months of the experiment, may indicate a geneticbased adaptability of the breed in Iran. CONCLUSIONS: Thepresent study shows the dynamic changes of general andbiochemical parameters in response to chronic heat stress and anacute stress that raises a possible tolerance of the breed againstheat stress.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
