Abstract
The effects of monensin supplement (33 mg/kg feed) on ruminal fermentation and body metabolism were studied in Brahman steers fed 5 kg lucerne hay daily at thermoneutral temperature (24�C) and after heat exposure [I day at 31�C (acute) or 5 days at 37�C (chronic)]. At 24�C, monensin lowered the concentrations of ammonia and protozoa in ruminal fluid and increased the plasma concentration of cholesterol but did not affect the circulating levels of urea, glucose, insulin, thyroxine (T4), triiodothyronine (T3), free T4 and free T3. Acute heat exposure lowered the plasma concentrations of thyroid hormones. Chronic heat exposure increased body temperature, the rate of dry matter digestion in the rumen and urinary nitrogen and allantoin excretion and lowered the plasma concentrations of cholesterol and differentially lowered the concentrations of the thyroid hormones. An increase in the concentration of ammonia in ruminal fluid was the only response to monensin at elevated body temperature that was uncharacteristic of its effects at normal body temperature. The results indicate that a monensin treatment of 33 mg/kg feed does not have any adverse effects on steers suffering metabolic derangement during hyperthermia.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: 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.