Abstract
Body composition, tenderness, growth hormone levels, thyroid activity and adrenal cortical activity were measured after feeding melengestrol acetate (MGA) to Holstein heifers. MGA was administered at 0.45 mg per animal per day either from 2.5 months of age or from first estrus. The heifers were fed corn silage and hay ad libitum in addition to either 0.9 or 4.5 kg grain per head daily and killed at first estrus or at breeding size. MGA feeding increased growth rates by 9.95% (P<.05) in one analysis. Mean jugular growth hormone level was significantly lower in MGA treated animals, and was significantly and negatively related to growth rate. The results suggested that MGA may preferentially stimulate the growth of lean tissue. Adrenal weights were significantly reduced in animals receiving MGA in one analysis. Plasma cortisol, adrenal cortisol and adrenal corticosterone concentrations, and adrenal fasiculata layer widths were significant (P<.05) less in animals fed MGA than in comparable animals without MGA.
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.
