Biochemistry and physiology of anabolic hormones used for improvement of meat production

Abstract

A number of hormones are involved in endocrine regulation of growth. In general, these hormones enhance body protein accretion and metabolise fat stores resulting in increased lean growth rates. Most practical importance was obtained by sex hormones (oestrogens and androgens), beta-agonists and growth hormone - whether legally or illegally. Efficiency of growth promotion ranges between 0% and +20% depending on the prerequisites such as species, breed, gender, age, reproductive status, body score or feeding of the animals. Oestrogens and androgens mediate their activity via intracellular receptors - directly in muscular tissue as well as indirectly via stimulation of growth hormone from the hypophysis and other growth factors from liver plus several further organs. In addition, mineral absorption in the gut is improved. The outstanding efficiency of trenbolone is based on its androgenic plus antiglucocorticoid activity. Melengestrolacetate is thought to act indirectly via stimulation of endogenous ovarian oestradiol in non-pregnant heifers. The necessary dosages and residue formations depend on the pharmacokinetic parameters of each substance and extrapolations between compounds are hardly possible. Growth hormone and beta2-agonists use independent pathways for growth promotion not related to steroid biochemistry.

Can potential for dark cutting be predicted by phenotype? Relationship between sex, carcass characteristics, and the incidence of dark cutting beef

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Effect of doe milking and supplementation using Dichrostachys cinerea pods on kid and doe performance in grazing goats during the dry season

“…Consistent superiority of males has been widely reported, with similar trends being reported by Tawonezvi and Ward (1987). This has been attributed to hormonal differences between sexes and their resultant effects on growth (Meyer, 2001).…”

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“…The use of anabolic agents in animal husbandry is very profitable as treated animals are growing faster and exhibit a higher amount of lean meat due to nitrogen retention and a decrease in total body fat [1]. In some countries, e.g.…”