Administration of dexamethasone per os in finishing bulls. I. Effects on productive traits, meat quality and cattle behaviour as indicator of welfare

Abstract

The study investigated the effects of prolonged oral administration of dexamethasone at a low daily dosage of 0.75 mg/head per day (Dexa) on beef cattle productive traits, behaviour and meat quality. In all, 14 finishing Marchigiana bulls were used in a trial that begun 56 days prior to slaughter, of which six bulls received treatment from day 5 to day 53, whereas the remaining animals were used for Control. The animals treated showed an increased average daily gain (1515 v. 1177 g/head per day; P , 0.05; s.e.d. 5 48.54) and improved warm carcass dressing percentage (60.8% v. 59.7%; P , 0.05; s.e.d. 5 0.32). Behavioural observation did not permit a clear distinction between treated and Control animals since feeding and social behaviour were similar in both groups. The bulls treated spent less time lying (16.5% v. 34.6%; P , 0.05; s.e.d. 5 4.38) and grooming (6.7% v. 11.9%; P , 0.05; s.e.d. 5 1.23), and this may indicate poorer welfare. No evidence of treatment was observed in other carcass traits, and redness was the only meat quality parameter slightly affected by corticosteroid administration.

Expression profiling of skeletal muscle in young bulls treated with steroidal growth promoters

“…A substantial increase in growth rate was observed in the initial phase of treatment, with significantly higher average daily gain. However, at the end of the experiment (7 wk) no significant differences in body and carcass size were observed in treated animals compared with controls (23).…”

“…Increased food intake and stimulated carbohydrate metabolism might therefore explain, at least partially, why the use of low doses of GCs, alone or in association with anabolic steroids, have long been reported to improve growth or slaughter performance in farm animals (1,28). Confirming these reports, a recent study (23) evaluated the effects on productive traits, animal behavior, and meat quality after oral administration of Dex at low daily dose (0.75 mg per day) in finishing bulls. A substantial increase in growth rate was observed in the initial phase of treatment, with significantly higher average daily gain.…”

“…Three additional control animals, matching in sex and age, collected in a previous experiment were included to increase sample size and to control for biological variation. The above experimental design builds upon a previous experiment where a similar Dex daily dose was forced-fed to treated animals for 7 wk (23). In the present study, the duration of treatment was shortened, and the mode of hormone administration modified by adding the compound directly to feed rather than force-feeding the animals with a capsule containing the hormone, in the attempt to more closely simulate the supposed illegal use of Dex in animal production.…”

Administration of dexamethasone per os in finishing bulls. II. Effects on blood parameters used as indicators of animal welfare

“…3 days prior to slaughter. Further description of the experimental design and treatments, housing system and feeding management are reported in Gottardo et al (2008).…”

A Histologic Study on Growth Promoter Target Organs of Slaughtered Beef in Molise Region (Italy)

“…Nevertheless, controversial growth promoter effects of dexamethasone have been discussed in several studies [21]. Corticosteroids showed the ability to increase the external fat thickness, carcass muscularity and dressing percentage.…”