RESUMO
OBJECTIVE: This work was carried out to evaluate the effects of zilpaterol hydrochloride (ZH) and ractopamine hydrochloride (RH) combined with immunocastration on the welfare traits of feedlot Nellore cattle. METHODS: Ninety-six Nellore males (average body weight [BW] = 409±50 kg; average 20 mo of age) were divided into two groups according to BW; half of the animals in each group received two doses of an immunocastration (ImC) vaccine in a 30 day interval, and the other half did not receive the vaccine (NoC). Afterward, the animals were housed and fed a common diet for 70 days. Then, they were split into three groups and fed one of the following diets for 30 additional days: control (CO) diet, with no ß-AA; ZH diet, containing 80 mg/d ZH; and RH diet, containing 300 mg/d RH. Welfare traits were assessed by monitoring body surface temperature using infrared thermography (IRT) and plasma cortisol and temperament measurements. RESULTS: There was no interaction between sexual condition and diet for any trait. The ImC and NoC groups did not differ in rectal and ocular temperatures. The ImC animals had higher flight speeds (p = 0.022) and tended to have higher cortisol levels (p = 0.059) than the NoC animals. Animals fed ZH and RH did not differ in cortisol levels, respiratory rate, rectal temperature, temperature measured by IRT, or temperament behaviour. CONCLUSION: The ImC animals showed a less stable temperament during handling practices than NoC, whereas ZH and RH supplementation had no adverse effects on animal welfare.
RESUMO
Several strategies have been studied to reduce the stress suffered by the animals during handling and all managements that are included in a routine. Among them, the effects of supplementation with chromium in the diet of ruminants have been fairly analyzed by reducing serum cortisol levels. Thus this study was designed to investigate the effects of dietary chromium supplementation on indicators of welfare of confined sheep. Sixty-four crossbred lambs White Dorper x Santa Ines, weaned at sixty days old, were divided into two groups for confinement for sixty days: control group and the group that received supplementation of 2 mg organic chromium daily. Every 14 days, the animals were weighed after fasting for 12 hours. Simultaneously, the reactivity of lambs was evaluated by scoring during the stay in the balance, followed by the flight speed, according to a composite score scale (CSS) consisted of a compilation which integrated the four scores described above, as follows: 1. Quiet and Docile animal (Breathing score = 1 or 2; vocalization score = 0; movement = 1; flight speed = 1); 2. Low reactivity or Alive (Breathing score = 2; vocalization score = 0 or 1; movement = 2; flight speed = 2); 3. Average reactivity or Restless (Breathing score = 2 or 3; vocalization score = 0 or 1; movement = 3; flight speed = 3 or 4); 4. Very Reactive or Disturbed (Breathing score = 3; vocalizatio
O artigo não apresenta resumo em português.
RESUMO
Several strategies have been studied to reduce the stress suffered by the animals during handling and all managements that are included in a routine. Among them, the effects of supplementation with chromium in the diet of ruminants have been fairly analyzed by reducing serum cortisol levels. Thus this study was designed to investigate the effects of dietary chromium supplementation on indicators of welfare of confined sheep. Sixty-four crossbred lambs White Dorper x Santa Ines, weaned at sixty days old, were divided into two groups for confinement for sixty days: control group and the group that received supplementation of 2 mg organic chromium daily. Every 14 days, the animals were weighed after fasting for 12 hours. Simultaneously, the reactivity of lambs was evaluated by scoring during the stay in the balance, followed by the flight speed, according to a composite score scale (CSS) consisted of a compilation which integrated the four scores described above, as follows: 1. Quiet and Docile animal (Breathing score = 1 or 2; vocalization score = 0; movement = 1; flight speed = 1); 2. Low reactivity or Alive (Breathing score = 2; vocalization score = 0 or 1; movement = 2; flight speed = 2); 3. Average reactivity or Restless (Breathing score = 2 or 3; vocalization score = 0 or 1; movement = 3; flight speed = 3 or 4); 4. Very Reactive or Disturbed (Breathing score = 3; vocalizatio
O artigo não apresenta resumo em português.